2016-12-08 14:22:51

by Bharat Kumar Gogada

[permalink] [raw]
Subject: ATH9 driver issues on ARM64

Hi,

Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/) on ARM64.
The end point is TP link wifi card with which supports only legacy interrupts.

We are trying to test it on ARM64 with (drivers/pci/host/pcie-xilinx-nwl.c) as root port.

EP is getting enumerated and able to link up.

But when we start scan system gets hanged.

When we took trace we see that after we start scan assert message is sent but
there is no de assert from end point.

What might cause end point not sending de assert ?

We are not seeing any issues on 32-bit ARM platform and X86 platform.

Regards,
Bharat


2016-12-08 14:56:25

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

[+cc Kalle, ath9k list]

On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> Hi,
>
> Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/)
> on ARM64. The end point is TP link wifi card with which supports
> only legacy interrupts.

If it works on other arches and the arm64 PCI enumeration works, my
first guess would be an INTx issue, e.g., maybe the driver is waiting
for an interrupt that never arrives.

> We are trying to test it on ARM64 with
> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
>
> EP is getting enumerated and able to link up.
>
> But when we start scan system gets hanged.

When you say the system hangs when you start a scan, I assume you mean
a wifi scan, not the PCI enumeration. A problem with a wifi scan
might cause a *process* to hang, but it shouldn't hang the entire
system.

> When we took trace we see that after we start scan assert message is
> sent but there is no de assert from end point.

Are you talking about a trace from a PCIe analyzer? Do you see an
Assert_INTx PCIe message on the link?

> What might cause end point not sending de assert ?

If the endpoint doesn't send a Deassert_INTx message, I expect that
would mean the driver didn't service the interrupt and remove the
condition that caused the device to assert the interrupt in the first
place.

If the driver didn't receive the interrupt, it couldn't service it, of
course. You could add a printk in the ath9k interrupt service
routine to see if you ever get there.

> We are not seeing any issues on 32-bit ARM platform and X86
> platform.

Can you collect a dmesg log (or, if the system hang means you can't
collect that, a console log with "ignore_loglevel"), and "lspci -vv"
output as root? That should have clues about whether the INTx got
routed correctly. /proc/interrupts should also show whether we're
receiving interrupts from the device.

Bjorn

2016-12-08 16:02:11

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> [+cc Kalle, ath9k list]
>
> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> > Hi,
> >
> > Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/)
> > on ARM64. The end point is TP link wifi card with which supports
> > only legacy interrupts.
>
> If it works on other arches and the arm64 PCI enumeration works, my
> first guess would be an INTx issue, e.g., maybe the driver is waiting
> for an interrupt that never arrives.
We are not sure for now.
>
> > We are trying to test it on ARM64 with
> > (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> >
> > EP is getting enumerated and able to link up.
> >
> > But when we start scan system gets hanged.
>
> When you say the system hangs when you start a scan, I assume you mean
> a wifi scan, not the PCI enumeration. A problem with a wifi scan
> might cause a *process* to hang, but it shouldn't hang the entire
> system.
>
Yes wifi scan.
> > When we took trace we see that after we start scan assert message is
> > sent but there is no de assert from end point.
>
> Are you talking about a trace from a PCIe analyzer? Do you see an
> Assert_INTx PCIe message on the link?
>
Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening when we do interface link up.
When we have less debug prints in Atheros driver, and do wifi scan we see Assert_INTx but never Deassert_INTx,
> > What might cause end point not sending de assert ?
>
> If the endpoint doesn't send a Deassert_INTx message, I expect that
> would mean the driver didn't service the interrupt and remove the
> condition that caused the device to assert the interrupt in the first
> place.
>
> If the driver didn't receive the interrupt, it couldn't service it, of
> course. You could add a printk in the ath9k interrupt service
> routine to see if you ever get there.
>
The interrupt behavior is changing w.r.t amount of debug prints we add. (I kept many prints to aid debug)
root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
[ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.074257] ath9k_hw_kill_interrupts 793
[ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.087882] ath9k_hw_kill_interrupts 793
[ 83.095450] ath9k_hw_enable_interrupts 821
[ 83.099557] ath9k_hw_enable_interrupts 825
[ 83.103721] ath9k_hw_enable_interrupts 832
[ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.112748] AR_SREV_9100 0
[ 83.115438] ath9k_hw_enable_interrupts 848
[ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.124389] ath9k_hw_intrpend 762
[ 83.127761] (AR_SREV_9340(ah) val 0
[ 83.131234] ath9k_hw_intrpend 767
[ 83.134628] ath_isr 603
[ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.146771] ath9k_hw_kill_interrupts 793
[ 83.150864] ath9k_hw_enable_interrupts 821
[ 83.154971] ath9k_hw_enable_interrupts 825
[ 83.159135] ath9k_hw_enable_interrupts 832
[ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.168161] AR_SREV_9100 0
[ 83.170852] ath9k_hw_enable_interrupts 848
[ 83.170855] ath9k_hw_intrpend 762
[ 83.178398] (AR_SREV_9340(ah) val 0
[ 83.181873] ath9k_hw_intrpend 767
[ 83.185265] ath_isr 603
[ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.197411] ath9k_hw_kill_interrupts 793
[ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.206258] ath9k_hw_enable_interrupts 821
[ 83.210368] ath9k_hw_enable_interrupts 825
[ 83.214531] ath9k_hw_enable_interrupts 832
[ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.223558] AR_SREV_9100 0
[ 83.226243] ath9k_hw_enable_interrupts 848
[ 83.226246] ath9k_hw_intrpend 762
[ 83.233794] (AR_SREV_9340(ah) val 0
[ 83.237268] ath9k_hw_intrpend 767
[ 83.240661] ath_isr 603
[ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.252806] ath9k_hw_kill_interrupts 793
[ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.261651] ath9k_hw_enable_interrupts 821
[ 83.265753] ath9k_hw_enable_interrupts 825
[ 83.269919] ath9k_hw_enable_interrupts 832
[ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.278945] AR_SREV_9100 0
[ 83.281630] ath9k_hw_enable_interrupts 848
[ 83.281633] ath9k_hw_intrpend 762
[ 83.281634] (AR_SREV_9340(ah) val 0
[ 83.281637] ath9k_hw_intrpend 767
[ 83.281648] ath_isr 603
[ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.281654] ath9k_hw_kill_interrupts 793
[ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
[ 83.317030] ath9k_hw_enable_interrupts 821
[ 83.321132] ath9k_hw_enable_interrupts 825
[ 83.325297] ath9k_hw_enable_interrupts 832
[ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
[ 83.334324] AR_SREV_9100 0
[ 83.337014] ath9k_hw_enable_interrupts 848
..
..
This log continues until I turn off board without obtaining scanning result.

In between I get following cpu stall outputs :
230.457179] INFO: rcu_sched self-detected stall on CPU
[ 230.457185] 2-...: (31314 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
[ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
[ 230.457191] Task dump for CPU 2:
[ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
[ 230.457207] Workqueue: phy0 ieee80211_scan_work
[ 230.457208] Call trace:
[ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198
[ 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20
[ 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8
[ 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50
[ 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0
[ 230.457239] [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748
[ 230.457243] [<ffffff80080e7cfc>] update_process_times+0x3c/0x68
[ 230.457249] [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
[ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90
[ 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
** 10 printk messages dropped ** [ 230.457302] f8c0: 0000000000000000 0000000005f5e0ff 000000000001379a 3866666666666620
[ 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000 ffffffc87b8010a8
[ 230.457310] f900: ffffff808a1b4057 ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000
[ 230.457314] f920: 0000000000000140 0000000000000006 ffffff800a1b3b10 ffffff800a1c39e8
[ 230.457318] f940: 000000000000002f ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990
[ 230.457322] f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234 0000000060000145
** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>] el1_irq+0xa0/0x100
** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
[ 230.457377] [<ffffff8008863690>] ieee80211_scan_work+0x1f8/0x480
[ 230.457383] [<ffffff80080b15d0>] process_one_work+0x120/0x378
[ 230.457386] [<ffffff80080b1870>] worker_thread+0x48/0x4b0
[ 230.457391] [<ffffff80080b7108>] kthread+0xd0/0xe8
[ 230.457395] [<ffffff8008085dd0>] ret_from_fork+0x10/0x40
[ 230.480389] ath9k_hw_intrpend 762


[ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024
[ 545.526189] INFO: rcu_sched self-detected stall on CPU
[ 545.526195] 2-...: (97636 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
[ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
[ 545.526201] Task dump for CPU 2:
[ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>] show_stack+0x14/0x20
** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>] arch_timer_handler_phys+0x30/0x40
[ 545.526284] [<ffffff80080dbe18>] handle_percpu_devid_irq+0x78/0xa0
[ 545.526291] [<ffffff80080d760c>] generic_handle_irq+0x24/0x38
[ 545.526296] [<ffffff80080d7944>] __handle_domain_irq+0x5c/0xb8
[ 545.526299] [<ffffff80080824bc>] gic_handle_irq+0x64/0xc0
[ 545.526302] Exception stack(0xffffffc87b07f870 to 0xffffffc87b07f990)
[ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8 0000000000000036
[ 545.526345] [<ffffff8008085720>] el1_irq+0xa0/0x100
[ 545.526349] [<ffffff80080d6234>] console_unlock+0x384/0x5b0
[ 545.526353] [<ffffff80080d673c>] vprintk_emit+0x2dc/0x4b0
[ 545.526357] [<ffffff80080d6a50>] vprintk_default+0x38/0x40
[ 545.526362] [<ffffff8008129704>] printk+0x58/0x60
[ 545.526366] [<ffffff800859e3e4>] ath9k_iowrite32+0x9c/0xa8
[ 545.526372] [<ffffff80085c7ca8>] ath9k_hw_kill_interrupts+0x28/0xf0
[ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts 793
[ 545.532890] ath9k_hw_enable_interrupts 821


But if we have less debug prints it does not reach EP handler sometimes, due to following
Condition in "kernel/irq/chip.c" in function handle_simple_irq

if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
desc->istate |= IRQS_PENDING;
goto out_unlock;
}
Here irqd_irq_disabled is being set to 1.

With lesser debug prints it stops after following prints:
root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
[ 54.781045] ath9k_hw_kill_interrupts 793
[ 54.785007] ath9k_hw_kill_interrupts 793
[ 54.792535] ath9k_hw_enable_interrupts 821
[ 54.796642] ath9k_hw_enable_interrupts 825
[ 54.800807] ath9k_hw_enable_interrupts 832
[ 54.804973] AR_SREV_9100 0
[ 54.807663] ath9k_hw_enable_interrupts 848
[ 54.811843] ath9k_hw_intrpend 762
[ 54.815211] (AR_SREV_9340(ah) val 0
[ 54.818684] ath9k_hw_intrpend 767
[ 54.822078] ath_isr 603
[ 54.824587] ath9k_hw_kill_interrupts 793
[ 54.828601] ath9k_hw_enable_interrupts 821
[ 54.832750] ath9k_hw_enable_interrupts 825
[ 54.836916] ath9k_hw_enable_interrupts 832
[ 54.841082] AR_SREV_9100 0
[ 54.843772] ath9k_hw_enable_interrupts 848
[ 54.843775] ath9k_hw_intrpend 762
[ 54.851319] (AR_SREV_9340(ah) val 0
[ 54.854793] ath9k_hw_intrpend 767
[ 54.858185] ath_isr 603
[ 54.860696] ath9k_hw_kill_interrupts 793
[ 54.864776] ath9k_hw_enable_interrupts 821
[ 54.867061] ath9k_hw_kill_interrupts 793
[ 54.872870] ath9k_hw_enable_interrupts 825
[ 54.877036] ath9k_hw_enable_interrupts 832
[ 54.881202] AR_SREV_9100 0
[ 54.883892] ath9k_hw_enable_interrupts 848
[ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=519
[ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
[ 75.982485] Task dump for CPU 0:
[ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
[ 75.992726] Call trace:
[ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
[ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
[ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=2097
[ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
[ 139.078489] Task dump for CPU 0:
[ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
[ 139.088731] Call trace:
[ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
[ 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500


> > We are not seeing any issues on 32-bit ARM platform and X86
> > platform.
>
> Can you collect a dmesg log (or, if the system hang means you can't
> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> output as root? That should have clues about whether the INTx got
> routed correctly. /proc/interrupts should also show whether we're
> receiving interrupts from the device.

Here is the lspci output:
00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal decode])
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Interrupt: pin A routed to IRQ 224
Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
I/O behind bridge: 00000000-00000fff
Memory behind bridge: e0000000-e00fffff
Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: [40] Power Management version 3
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
DevCap: MaxPayload 256 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend+
LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported, Exit Latency L0s unlimited, L1 unlimited
ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible+
RootCap: CRSVisible+
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-, OBFF Not Supported ARIFwd-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled ARIFwd-
LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
Capabilities: [10c v1] Virtual Channel
Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
Arb: Fixed- WRR32- WRR64- WRR128-
Ctrl: ArbSelect=Fixed
Status: InProgress-
VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
Status: NegoPending- InProgress-
Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1 Len=018 <?>

01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network Adapter (rev 01)
Subsystem: Qualcomm Atheros Device 3112
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 128 bytes
Interrupt: pin A routed to IRQ 224
Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
[virtual] Expansion ROM at e0020000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA PME(D0+,D1+,D2-,D3hot+,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
Address: 0000000000000000 Data: 0000
Masking: 00000000 Pending: 00000000
Capabilities: [70] Express (v2) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <1us, L1 <8us
ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <2us, L1 <64us
ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR-, OBFF Not Supported
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
Capabilities: [100 v1] Advanced Error Reporting
UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
Capabilities: [140 v1] Virtual Channel
Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
Arb: Fixed- WRR32- WRR64- WRR128-
Ctrl: ArbSelect=Fixed
Status: InProgress-
VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
Status: NegoPending- InProgress-
Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
Kernel driver in use: ath9k

Here is the cat /proc/interrupts (after we do interface up):

root@:~# ifconfig wlan0 up
[ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
1: 0 0 0 0 GICv2 29 Edge arch_timer
2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
12: 0 0 0 0 GICv2 156 Level zynqmp-dma
13: 0 0 0 0 GICv2 157 Level zynqmp-dma
14: 0 0 0 0 GICv2 158 Level zynqmp-dma
15: 0 0 0 0 GICv2 159 Level zynqmp-dma
16: 0 0 0 0 GICv2 160 Level zynqmp-dma
17: 0 0 0 0 GICv2 161 Level zynqmp-dma
18: 0 0 0 0 GICv2 162 Level zynqmp-dma
19: 0 0 0 0 GICv2 163 Level zynqmp-dma
20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
30: 0 0 0 0 GICv2 95 Level eth0, eth0
206: 314 0 0 0 GICv2 49 Level cdns-i2c
207: 40 0 0 0 GICv2 50 Level cdns-i2c
209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
218: 61 0 0 0 GICv2 81 Level mmc0
219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
220: 471 0 0 0 GICv2 53 Level xuartps
223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
224: 3 0 0 0 dummy 1 Edge ath9k
225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1

Regards,
Bharat

2016-12-08 17:37:17

by Kalle Valo

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

Bharat Kumar Gogada <[email protected]> writes:

> > [+cc Kalle, ath9k list]

Thanks, but please also CC linux-wireless. Full thread below for the
folks there.

>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
>> > Hi,
>> >
>> > Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/)
>> > on ARM64. The end point is TP link wifi card with which supports
>> > only legacy interrupts.
>>
>> If it works on other arches and the arm64 PCI enumeration works, my
>> first guess would be an INTx issue, e.g., maybe the driver is waiting
>> for an interrupt that never arrives.
> We are not sure for now.
>>
>> > We are trying to test it on ARM64 with
>> > (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
>> >
>> > EP is getting enumerated and able to link up.
>> >
>> > But when we start scan system gets hanged.
>>
>> When you say the system hangs when you start a scan, I assume you mean
>> a wifi scan, not the PCI enumeration. A problem with a wifi scan
>> might cause a *process* to hang, but it shouldn't hang the entire
>> system.
>>
> Yes wifi scan.
>> > When we took trace we see that after we start scan assert message is
>> > sent but there is no de assert from end point.
>>
>> Are you talking about a trace from a PCIe analyzer? Do you see an
>> Assert_INTx PCIe message on the link?
>>
> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening when we do interface link up.
> When we have less debug prints in Atheros driver, and do wifi scan we see Assert_INTx but never Deassert_INTx,
>> > What might cause end point not sending de assert ?
>>
>> If the endpoint doesn't send a Deassert_INTx message, I expect that
>> would mean the driver didn't service the interrupt and remove the
>> condition that caused the device to assert the interrupt in the first
>> place.
>>
>> If the driver didn't receive the interrupt, it couldn't service it, of
>> course. You could add a printk in the ath9k interrupt service
>> routine to see if you ever get there.
>>
> The interrupt behavior is changing w.r.t amount of debug prints we add. (I kept many prints to aid debug)
> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.074257] ath9k_hw_kill_interrupts 793
> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.087882] ath9k_hw_kill_interrupts 793
> [ 83.095450] ath9k_hw_enable_interrupts 821
> [ 83.099557] ath9k_hw_enable_interrupts 825
> [ 83.103721] ath9k_hw_enable_interrupts 832
> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.112748] AR_SREV_9100 0
> [ 83.115438] ath9k_hw_enable_interrupts 848
> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.124389] ath9k_hw_intrpend 762
> [ 83.127761] (AR_SREV_9340(ah) val 0
> [ 83.131234] ath9k_hw_intrpend 767
> [ 83.134628] ath_isr 603
> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.146771] ath9k_hw_kill_interrupts 793
> [ 83.150864] ath9k_hw_enable_interrupts 821
> [ 83.154971] ath9k_hw_enable_interrupts 825
> [ 83.159135] ath9k_hw_enable_interrupts 832
> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.168161] AR_SREV_9100 0
> [ 83.170852] ath9k_hw_enable_interrupts 848
> [ 83.170855] ath9k_hw_intrpend 762
> [ 83.178398] (AR_SREV_9340(ah) val 0
> [ 83.181873] ath9k_hw_intrpend 767
> [ 83.185265] ath_isr 603
> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.197411] ath9k_hw_kill_interrupts 793
> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.206258] ath9k_hw_enable_interrupts 821
> [ 83.210368] ath9k_hw_enable_interrupts 825
> [ 83.214531] ath9k_hw_enable_interrupts 832
> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.223558] AR_SREV_9100 0
> [ 83.226243] ath9k_hw_enable_interrupts 848
> [ 83.226246] ath9k_hw_intrpend 762
> [ 83.233794] (AR_SREV_9340(ah) val 0
> [ 83.237268] ath9k_hw_intrpend 767
> [ 83.240661] ath_isr 603
> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.252806] ath9k_hw_kill_interrupts 793
> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.261651] ath9k_hw_enable_interrupts 821
> [ 83.265753] ath9k_hw_enable_interrupts 825
> [ 83.269919] ath9k_hw_enable_interrupts 832
> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.278945] AR_SREV_9100 0
> [ 83.281630] ath9k_hw_enable_interrupts 848
> [ 83.281633] ath9k_hw_intrpend 762
> [ 83.281634] (AR_SREV_9340(ah) val 0
> [ 83.281637] ath9k_hw_intrpend 767
> [ 83.281648] ath_isr 603
> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.281654] ath9k_hw_kill_interrupts 793
> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> [ 83.317030] ath9k_hw_enable_interrupts 821
> [ 83.321132] ath9k_hw_enable_interrupts 825
> [ 83.325297] ath9k_hw_enable_interrupts 832
> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> [ 83.334324] AR_SREV_9100 0
> [ 83.337014] ath9k_hw_enable_interrupts 848
> ..
> ..
> This log continues until I turn off board without obtaining scanning result.
>
> In between I get following cpu stall outputs :
> 230.457179] INFO: rcu_sched self-detected stall on CPU
> [ 230.457185] 2-...: (31314 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> [ 230.457191] Task dump for CPU 2:
> [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> [ 230.457207] Workqueue: phy0 ieee80211_scan_work
> [ 230.457208] Call trace:
> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198
> [ 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20
> [ 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8
> [ 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50
> [ 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0
> [ 230.457239] [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748
> [ 230.457243] [<ffffff80080e7cfc>] update_process_times+0x3c/0x68
> [ 230.457249] [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90
> [ 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> ** 10 printk messages dropped ** [ 230.457302] f8c0: 0000000000000000 0000000005f5e0ff 000000000001379a 3866666666666620
> [ 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000 ffffffc87b8010a8
> [ 230.457310] f900: ffffff808a1b4057 ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000
> [ 230.457314] f920: 0000000000000140 0000000000000006 ffffff800a1b3b10 ffffff800a1c39e8
> [ 230.457318] f940: 000000000000002f ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990
> [ 230.457322] f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234 0000000060000145
> ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>] el1_irq+0xa0/0x100
> ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
> [ 230.457377] [<ffffff8008863690>] ieee80211_scan_work+0x1f8/0x480
> [ 230.457383] [<ffffff80080b15d0>] process_one_work+0x120/0x378
> [ 230.457386] [<ffffff80080b1870>] worker_thread+0x48/0x4b0
> [ 230.457391] [<ffffff80080b7108>] kthread+0xd0/0xe8
> [ 230.457395] [<ffffff8008085dd0>] ret_from_fork+0x10/0x40
> [ 230.480389] ath9k_hw_intrpend 762
>
>
> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024
> [ 545.526189] INFO: rcu_sched self-detected stall on CPU
> [ 545.526195] 2-...: (97636 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> [ 545.526201] Task dump for CPU 2:
> [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>] show_stack+0x14/0x20
> ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>] arch_timer_handler_phys+0x30/0x40
> [ 545.526284] [<ffffff80080dbe18>] handle_percpu_devid_irq+0x78/0xa0
> [ 545.526291] [<ffffff80080d760c>] generic_handle_irq+0x24/0x38
> [ 545.526296] [<ffffff80080d7944>] __handle_domain_irq+0x5c/0xb8
> [ 545.526299] [<ffffff80080824bc>] gic_handle_irq+0x64/0xc0
> [ 545.526302] Exception stack(0xffffffc87b07f870 to 0xffffffc87b07f990)
> [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8 0000000000000036
> [ 545.526345] [<ffffff8008085720>] el1_irq+0xa0/0x100
> [ 545.526349] [<ffffff80080d6234>] console_unlock+0x384/0x5b0
> [ 545.526353] [<ffffff80080d673c>] vprintk_emit+0x2dc/0x4b0
> [ 545.526357] [<ffffff80080d6a50>] vprintk_default+0x38/0x40
> [ 545.526362] [<ffffff8008129704>] printk+0x58/0x60
> [ 545.526366] [<ffffff800859e3e4>] ath9k_iowrite32+0x9c/0xa8
> [ 545.526372] [<ffffff80085c7ca8>] ath9k_hw_kill_interrupts+0x28/0xf0
> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
> ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts 793
> [ 545.532890] ath9k_hw_enable_interrupts 821
>
>
> But if we have less debug prints it does not reach EP handler sometimes, due to following
> Condition in "kernel/irq/chip.c" in function handle_simple_irq
>
> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> desc->istate |= IRQS_PENDING;
> goto out_unlock;
> }
> Here irqd_irq_disabled is being set to 1.
>
> With lesser debug prints it stops after following prints:
> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> [ 54.781045] ath9k_hw_kill_interrupts 793
> [ 54.785007] ath9k_hw_kill_interrupts 793
> [ 54.792535] ath9k_hw_enable_interrupts 821
> [ 54.796642] ath9k_hw_enable_interrupts 825
> [ 54.800807] ath9k_hw_enable_interrupts 832
> [ 54.804973] AR_SREV_9100 0
> [ 54.807663] ath9k_hw_enable_interrupts 848
> [ 54.811843] ath9k_hw_intrpend 762
> [ 54.815211] (AR_SREV_9340(ah) val 0
> [ 54.818684] ath9k_hw_intrpend 767
> [ 54.822078] ath_isr 603
> [ 54.824587] ath9k_hw_kill_interrupts 793
> [ 54.828601] ath9k_hw_enable_interrupts 821
> [ 54.832750] ath9k_hw_enable_interrupts 825
> [ 54.836916] ath9k_hw_enable_interrupts 832
> [ 54.841082] AR_SREV_9100 0
> [ 54.843772] ath9k_hw_enable_interrupts 848
> [ 54.843775] ath9k_hw_intrpend 762
> [ 54.851319] (AR_SREV_9340(ah) val 0
> [ 54.854793] ath9k_hw_intrpend 767
> [ 54.858185] ath_isr 603
> [ 54.860696] ath9k_hw_kill_interrupts 793
> [ 54.864776] ath9k_hw_enable_interrupts 821
> [ 54.867061] ath9k_hw_kill_interrupts 793
> [ 54.872870] ath9k_hw_enable_interrupts 825
> [ 54.877036] ath9k_hw_enable_interrupts 832
> [ 54.881202] AR_SREV_9100 0
> [ 54.883892] ath9k_hw_enable_interrupts 848
> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=519
> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> [ 75.982485] Task dump for CPU 0:
> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> [ 75.992726] Call trace:
> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=2097
> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> [ 139.078489] Task dump for CPU 0:
> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> [ 139.088731] Call trace:
> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> [ 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
>
>
>> > We are not seeing any issues on 32-bit ARM platform and X86
>> > platform.
>>
>> Can you collect a dmesg log (or, if the system hang means you can't
>> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
>> output as root? That should have clues about whether the INTx got
>> routed correctly. /proc/interrupts should also show whether we're
>> receiving interrupts from the device.
>
> Here is the lspci output:
> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal decode])
> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
> Latency: 0
> Interrupt: pin A routed to IRQ 224
> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> I/O behind bridge: 00000000-00000fff
> Memory behind bridge: e0000000-e00fffff
> Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> Capabilities: [40] Power Management version 3
> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> DevCap: MaxPayload 256 bytes, PhantFunc 0
> ExtTag- RBE+
> DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> MaxPayload 128 bytes, MaxReadReq 512 bytes
> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend+
> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported, Exit Latency L0s unlimited, L1 unlimited
> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible+
> RootCap: CRSVisible+
> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-, OBFF Not Supported ARIFwd-
> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled ARIFwd-
> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
> Compliance De-emphasis: -6dB
> LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
> EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> Capabilities: [10c v1] Virtual Channel
> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> Arb: Fixed- WRR32- WRR64- WRR128-
> Ctrl: ArbSelect=Fixed
> Status: InProgress-
> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> Status: NegoPending- InProgress-
> Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1 Len=018 <?>
>
> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network Adapter (rev 01)
> Subsystem: Qualcomm Atheros Device 3112
> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
> Latency: 0, Cache Line Size: 128 bytes
> Interrupt: pin A routed to IRQ 224
> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> Capabilities: [40] Power Management version 3
> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA PME(D0+,D1+,D2-,D3hot+,D3cold-)
> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> Address: 0000000000000000 Data: 0000
> Masking: 00000000 Pending: 00000000
> Capabilities: [70] Express (v2) Endpoint, MSI 00
> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <1us, L1 <8us
> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W
> DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> MaxPayload 128 bytes, MaxReadReq 512 bytes
> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <2us, L1 <64us
> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
> DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR-, OBFF Not Supported
> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-
> Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
> Compliance De-emphasis: -6dB
> LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
> EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
> Capabilities: [100 v1] Advanced Error Reporting
> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
> AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
> Capabilities: [140 v1] Virtual Channel
> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> Arb: Fixed- WRR32- WRR64- WRR128-
> Ctrl: ArbSelect=Fixed
> Status: InProgress-
> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> Status: NegoPending- InProgress-
> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> Kernel driver in use: ath9k
>
> Here is the cat /proc/interrupts (after we do interface up):
>
> root@:~# ifconfig wlan0 up
> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> CPU0 CPU1 CPU2 CPU3
> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
> 218: 61 0 0 0 GICv2 81 Level mmc0
> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> 220: 471 0 0 0 GICv2 53 Level xuartps
> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> 224: 3 0 0 0 dummy 1 Edge ath9k
> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
>
> Regards,
> Bharat

--
Kalle Valo

2016-12-08 18:07:10

by Marc Zyngier

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

On 08/12/16 15:29, Bharat Kumar Gogada wrote:

Two things:

> Here is the cat /proc/interrupts (after we do interface up):
>
> root@:~# ifconfig wlan0 up
> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> CPU0 CPU1 CPU2 CPU3
> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1

I'm not even going to consider looking at something that is running out
of tree code. So please start things with a fresh kernel that doesn't
contain stuff we can't debug.

> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
> 218: 61 0 0 0 GICv2 81 Level mmc0
> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> 220: 471 0 0 0 GICv2 53 Level xuartps
> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> 224: 3 0 0 0 dummy 1 Edge ath9k

What is this "dummy" controller? And if that's supposed to be a legacy
interrupt from the PCI device, it has the wrong trigger.

Thanks,

M.
--
Jazz is not dead. It just smells funny...

2016-12-08 18:33:30

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
>
> Two things:
>
> > Here is the cat /proc/interrupts (after we do interface up):
> >
> > root@:~# ifconfig wlan0 up
> > [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> > root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > CPU0 CPU1 CPU2 CPU3
> > 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> > 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP,
> Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
>
> I'm not even going to consider looking at something that is running out of tree
> code. So please start things with a fresh kernel that doesn't contain stuff we
> can't debug.
>
Ok will test with fresh kernel.

> > 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
> > 218: 61 0 0 0 GICv2 81 Level mmc0
> > 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> > 220: 471 0 0 0 GICv2 53 Level xuartps
> > 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > 224: 3 0 0 0 dummy 1 Edge ath9k
>
> What is this "dummy" controller? And if that's supposed to be a legacy interrupt
> from the PCI device, it has the wrong trigger.

Yes it is for legacy interrupt, wrong trigger means ?

Thanks & Regards,
Bharat

2016-12-08 19:09:38

by Marc Zyngier

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

On 08/12/16 18:33, Bharat Kumar Gogada wrote:
>> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
>>
>> Two things:
>>
>>> Here is the cat /proc/interrupts (after we do interface up):
>>>
>>> root@:~# ifconfig wlan0 up
>>> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
>>> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
>>> CPU0 CPU1 CPU2 CPU3
>>> 1: 0 0 0 0 GICv2 29 Edge arch_timer
>>> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer

By the way, please use a recent kernel. Seeing edge here means you're
running with something that is a bit old (and broken). And since you
haven't even said what revision of the kernel you're using, hslping you
is not an easy task. tglx told you something similar about a week ago.

>>> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
>>> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
>>> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
>>> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
>>> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
>>> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
>>> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
>>> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
>>> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP,
>> Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
>>
>> I'm not even going to consider looking at something that is running out of tree
>> code. So please start things with a fresh kernel that doesn't contain stuff we
>> can't debug.
>>
> Ok will test with fresh kernel.
>
>>> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
>>> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
>>> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
>>> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
>>> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
>>> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
>>> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
>>> 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
>>> 218: 61 0 0 0 GICv2 81 Level mmc0
>>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
>>> 220: 471 0 0 0 GICv2 53 Level xuartps
>>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
>>> 224: 3 0 0 0 dummy 1 Edge ath9k
>>
>> What is this "dummy" controller? And if that's supposed to be a legacy interrupt
>> from the PCI device, it has the wrong trigger.
>
> Yes it is for legacy interrupt, wrong trigger means ?

Aren't legacy interrupts supposed to be *level* triggered, and not edge?

Thanks,

M.
--
Jazz is not dead. It just smells funny...

2016-12-09 02:07:34

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> On 08/12/16 18:33, Bharat Kumar Gogada wrote:
> >> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
> >>
> >> Two things:
> >>
> >>> Here is the cat /proc/interrupts (after we do interface up):
> >>>
> >>> root@:~# ifconfig wlan0 up
> >>> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> >>> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> >>> CPU0 CPU1 CPU2 CPU3
> >>> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> >>> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
>
> By the way, please use a recent kernel. Seeing edge here means you're running
> with something that is a bit old (and broken). And since you haven't even said
> what revision of the kernel you're using, hslping you is not an easy task. tglx told
> you something similar about a week ago.
>
> >>> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> >>> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> >>> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> >>> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> >>> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> >>> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> >>> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> >>> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> >>> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> Mali_GP,
> >> Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> >>
> >> I'm not even going to consider looking at something that is running
> >> out of tree code. So please start things with a fresh kernel that
> >> doesn't contain stuff we can't debug.
> >>
> > Ok will test with fresh kernel.
> >
> >>> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> >>> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> >>> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> >>> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
This irq line is handling miscellaneous interrupts this shows level triggered.
> >>> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> >>> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> >>> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> >>> 217: 0 0 0 0 GICv2 165 Level ahci-
> ceva[fd0c0000.ahci]
> >>> 218: 61 0 0 0 GICv2 81 Level mmc0
> >>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> >>> 220: 471 0 0 0 GICv2 53 Level xuartps
> >>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> >>> 224: 3 0 0 0 dummy 1 Edge ath9k
> >>
> >> What is this "dummy" controller? And if that's supposed to be a
> >> legacy interrupt from the PCI device, it has the wrong trigger.
> >
> > Yes it is for legacy interrupt, wrong trigger means ?
>
> Aren't legacy interrupts supposed to be *level* triggered, and not edge?
>
Yes agreed.
For legacy interrupts im using irq_set_chained_handler_and_data so the irq line between bridge and GIC
Will not be shown here. The above how is virq for legacy, which is given by kernel, not sure why its state is set
to edge.


Thanks & Regards,
Bharat

2016-12-09 02:54:35

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> > >> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
> > >>
> > >> Two things:
> > >>
> > >>> Here is the cat /proc/interrupts (after we do interface up):
> > >>>
> > >>> root@:~# ifconfig wlan0 up
> > >>> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> > >>> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > >>> CPU0 CPU1 CPU2 CPU3
> > >>> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > >>> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> >
> > By the way, please use a recent kernel. Seeing edge here means you're
> > running with something that is a bit old (and broken). And since you
> > haven't even said what revision of the kernel you're using, hslping
> > you is not an easy task. tglx told you something similar about a week ago.
> >
> > >>> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > >>> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > >>> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > >>> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > >>> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > >>> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > >>> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > >>> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > >>> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> > Mali_GP,
> > >> Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > >>
> > >> I'm not even going to consider looking at something that is running
> > >> out of tree code. So please start things with a fresh kernel that
> > >> doesn't contain stuff we can't debug.
> > >>
> > > Ok will test with fresh kernel.
> > >
> > >>> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > >>> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > >>> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > >>> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> This irq line is handling miscellaneous interrupts this shows level triggered.
> > >>> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > >>> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > >>> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > >>> 217: 0 0 0 0 GICv2 165 Level ahci-
> > ceva[fd0c0000.ahci]
> > >>> 218: 61 0 0 0 GICv2 81 Level mmc0
> > >>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global
> fault
> > >>> 220: 471 0 0 0 GICv2 53 Level xuartps
> > >>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > >>> 224: 3 0 0 0 dummy 1 Edge ath9k
> > >>
> > >> What is this "dummy" controller? And if that's supposed to be a
> > >> legacy interrupt from the PCI device, it has the wrong trigger.
> > >
> > > Yes it is for legacy interrupt, wrong trigger means ?
> >
> > Aren't legacy interrupts supposed to be *level* triggered, and not edge?
> >
> Yes agreed.
> For legacy interrupts im using irq_set_chained_handler_and_data so the irq line
> between bridge and GIC Will not be shown here. The above how is virq for
> legacy, which is given by kernel, not sure why its state is set to edge.
>
>

Here I'm adding fresh kernel log: (using 4.6.0 kernel version)
root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
1: 0 0 0 0 GICv2 29 Edge arch_timer
2: 1368 1294 1655 2657 GICv2 30 Edge arch_timer
30: 0 0 0 0 GICv2 95 Level eth0, eth0
206: 311 0 0 0 GICv2 49 Level cdns-i2c
207: 40 0 0 0 GICv2 50 Level cdns-i2c
209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
214: 7 0 0 0 GICv2 47 Level ff0f0000.spi
215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
218: 0 0 0 0 GICv2 81 Level mmc0
219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
220: 126 0 0 0 GICv2 53 Level xuartps
224: 3 0 0 0 dummy 1 Edge ath9k
IPI0: 1293 1003 914 671 Rescheduling interrupts
IPI1: 77 78 25 55 Function call interrupts
IPI2: 0 0 0 0 CPU stop interrupts
IPI3: 0 0 0 0 Timer broadcast interrupts
IPI4: 0 0 0 0 IRQ work interrupts
IPI5: 0 0 0 0 CPU wake-up interrupts


root@Xilinx-ZCU102-2016_3:~#iw dev wlan0 scan
[ 95.869644] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 95.875051] 0-...: (1 GPs behind) idle=659/140000000000001/0 softirq=1166/1166 fqs=257
[ 95.883125] (detected by 3, t=5253 jiffies, g=217, c=216, q=54)
[ 95.889108] Task dump for CPU 0:
[ 95.892318] kworker/u8:0 R running task 0 6 2 0x00000002
[ 95.899359] Workqueue: phy0 ieee80211_scan_work
[ 95.903862] Call trace:
[ 95.906299] [<ffffff8008086b14>] __switch_to+0x9c/0xd0
[ 95.911417] [<ffffffc87b87fc00>] 0xffffffc87b87fc00
[ 158.969641] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 158.975046] 0-...: (1 GPs behind) idle=659/140000000000001/0 softirq=1166/1166 fqs=1028
[ 158.983209] (detected by 3, t=21028 jiffies, g=217, c=216, q=54)
[ 158.989278] Task dump for CPU 0:
[ 158.992489] kworker/u8:0 R running task 0 6 2 0x00000002
[ 158.999523] Workqueue: phy0 ieee80211_scan_work
[ 159.004032] Call trace:
[ 159.006467] [<ffffff8008086b14>] __switch_to+0x9c/0xd0
[ 159.011588] [<ffffffc87b87fc00>] 0xffffffc87b87fc00


Thans & Regards,
Bharat

2016-12-09 05:00:43

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

Hi,
Can any one tell, when exactly the chip sends ASSERT & DEASSERT in driver.
It might help us to debug issue further.

Thanks & Regards,
Bharat

> > > [+cc Kalle, ath9k list]
>
> Thanks, but please also CC linux-wireless. Full thread below for the folks there.
>
> >> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> >> > Hi,
> >> >
> >> > Did anyone test Atheros ATH9
> >> > driver(drivers/net/wireless/ath/ath9k/)
> >> > on ARM64. The end point is TP link wifi card with which supports
> >> > only legacy interrupts.
> >>
> >> If it works on other arches and the arm64 PCI enumeration works, my
> >> first guess would be an INTx issue, e.g., maybe the driver is waiting
> >> for an interrupt that never arrives.
> > We are not sure for now.
> >>
> >> > We are trying to test it on ARM64 with
> >> > (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> >> >
> >> > EP is getting enumerated and able to link up.
> >> >
> >> > But when we start scan system gets hanged.
> >>
> >> When you say the system hangs when you start a scan, I assume you
> >> mean a wifi scan, not the PCI enumeration. A problem with a wifi
> >> scan might cause a *process* to hang, but it shouldn't hang the
> >> entire system.
> >>
> > Yes wifi scan.
> >> > When we took trace we see that after we start scan assert message
> >> > is sent but there is no de assert from end point.
> >>
> >> Are you talking about a trace from a PCIe analyzer? Do you see an
> >> Assert_INTx PCIe message on the link?
> >>
> > Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening
> when we do interface link up.
> > When we have less debug prints in Atheros driver, and do wifi scan we
> > see Assert_INTx but never Deassert_INTx,
> >> > What might cause end point not sending de assert ?
> >>
> >> If the endpoint doesn't send a Deassert_INTx message, I expect that
> >> would mean the driver didn't service the interrupt and remove the
> >> condition that caused the device to assert the interrupt in the first
> >> place.
> >>
> >> If the driver didn't receive the interrupt, it couldn't service it,
> >> of course. You could add a printk in the ath9k interrupt service
> >> routine to see if you ever get there.
> >>
> > The interrupt behavior is changing w.r.t amount of debug prints we
> > add. (I kept many prints to aid debug) root@Xilinx-ZCU102-2016_3:~# iw dev
> wlan0 scan
> > [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.074257] ath9k_hw_kill_interrupts 793
> > [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.087882] ath9k_hw_kill_interrupts 793
> > [ 83.095450] ath9k_hw_enable_interrupts 821
> > [ 83.099557] ath9k_hw_enable_interrupts 825
> > [ 83.103721] ath9k_hw_enable_interrupts 832
> > [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.112748] AR_SREV_9100 0
> > [ 83.115438] ath9k_hw_enable_interrupts 848
> > [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.124389] ath9k_hw_intrpend 762
> > [ 83.127761] (AR_SREV_9340(ah) val 0
> > [ 83.131234] ath9k_hw_intrpend 767
> > [ 83.134628] ath_isr 603
> > [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.146771] ath9k_hw_kill_interrupts 793
> > [ 83.150864] ath9k_hw_enable_interrupts 821
> > [ 83.154971] ath9k_hw_enable_interrupts 825
> > [ 83.159135] ath9k_hw_enable_interrupts 832
> > [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.168161] AR_SREV_9100 0
> > [ 83.170852] ath9k_hw_enable_interrupts 848
> > [ 83.170855] ath9k_hw_intrpend 762
> > [ 83.178398] (AR_SREV_9340(ah) val 0
> > [ 83.181873] ath9k_hw_intrpend 767
> > [ 83.185265] ath_isr 603
> > [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.197411] ath9k_hw_kill_interrupts 793
> > [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.206258] ath9k_hw_enable_interrupts 821
> > [ 83.210368] ath9k_hw_enable_interrupts 825
> > [ 83.214531] ath9k_hw_enable_interrupts 832
> > [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.223558] AR_SREV_9100 0
> > [ 83.226243] ath9k_hw_enable_interrupts 848
> > [ 83.226246] ath9k_hw_intrpend 762
> > [ 83.233794] (AR_SREV_9340(ah) val 0
> > [ 83.237268] ath9k_hw_intrpend 767
> > [ 83.240661] ath_isr 603
> > [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.252806] ath9k_hw_kill_interrupts 793
> > [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.261651] ath9k_hw_enable_interrupts 821
> > [ 83.265753] ath9k_hw_enable_interrupts 825
> > [ 83.269919] ath9k_hw_enable_interrupts 832
> > [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.278945] AR_SREV_9100 0
> > [ 83.281630] ath9k_hw_enable_interrupts 848
> > [ 83.281633] ath9k_hw_intrpend 762
> > [ 83.281634] (AR_SREV_9340(ah) val 0
> > [ 83.281637] ath9k_hw_intrpend 767
> > [ 83.281648] ath_isr 603
> > [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.281654] ath9k_hw_kill_interrupts 793
> > [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> > [ 83.317030] ath9k_hw_enable_interrupts 821
> > [ 83.321132] ath9k_hw_enable_interrupts 825
> > [ 83.325297] ath9k_hw_enable_interrupts 832
> > [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> > [ 83.334324] AR_SREV_9100 0
> > [ 83.337014] ath9k_hw_enable_interrupts 848
> > ..
> > ..
> > This log continues until I turn off board without obtaining scanning result.
> >
> > In between I get following cpu stall outputs :
> > 230.457179] INFO: rcu_sched self-detected stall on CPU
> > [ 230.457185] 2-...: (31314 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> > [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> > [ 230.457191] Task dump for CPU 2:
> > [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> > [ 230.457207] Workqueue: phy0 ieee80211_scan_work [ 230.457208] Call
> > trace:
> > [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> > 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [ 230.457224]
> > [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [ 230.457228]
> > [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [ 230.457233]
> > [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0 [ 230.457239]
> > [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748 [ 230.457243]
> > [<ffffff80080e7cfc>] update_process_times+0x3c/0x68 [ 230.457249]
> > [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> > [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90 [
> > 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> > ** 10 printk messages dropped ** [ 230.457302] f8c0: 0000000000000000
> > 0000000005f5e0ff 000000000001379a 3866666666666620 [ 230.457306]
> > f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000
> > ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> > ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [ 230.457314]
> > f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> > ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> > ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [ 230.457322]
> > f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> > 0000000060000145
> > ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>]
> > el1_irq+0xa0/0x100
> > ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>]
> > ieee80211_hw_config+0x50/0x290 [ 230.457377] [<ffffff8008863690>]
> > ieee80211_scan_work+0x1f8/0x480 [ 230.457383] [<ffffff80080b15d0>]
> > process_one_work+0x120/0x378 [ 230.457386] [<ffffff80080b1870>]
> > worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> > kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> ret_from_fork+0x10/0x40
> > [ 230.480389] ath9k_hw_intrpend 762
> >
> >
> > [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [ 545.526189]
> > INFO: rcu_sched self-detected stall on CPU
> > [ 545.526195] 2-...: (97636 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> > [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> > [ 545.526201] Task dump for CPU 2:
> > [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> > ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>]
> > show_stack+0x14/0x20
> > ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>]
> > arch_timer_handler_phys+0x30/0x40 [ 545.526284] [<ffffff80080dbe18>]
> > handle_percpu_devid_irq+0x78/0xa0 [ 545.526291] [<ffffff80080d760c>]
> > generic_handle_irq+0x24/0x38 [ 545.526296] [<ffffff80080d7944>]
> > __handle_domain_irq+0x5c/0xb8 [ 545.526299] [<ffffff80080824bc>]
> > gic_handle_irq+0x64/0xc0 [ 545.526302] Exception stack(0xffffffc87b07f870
> to 0xffffffc87b07f990)
> > [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> > ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8
> > 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> > el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> > console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> > vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> > vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> > printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> > ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> > ath9k_hw_kill_interrupts+0x28/0xf0
> > [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> > ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>]
> ieee80211_hw_config+0x50/0x290
> > ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts
> 793
> > [ 545.532890] ath9k_hw_enable_interrupts 821
> >
> >
> > But if we have less debug prints it does not reach EP handler
> > sometimes, due to following Condition in "kernel/irq/chip.c" in
> > function handle_simple_irq
> >
> > if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> > desc->istate |= IRQS_PENDING;
> > goto out_unlock;
> > }
> > Here irqd_irq_disabled is being set to 1.
> >
> > With lesser debug prints it stops after following prints:
> > root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> > [ 54.781045] ath9k_hw_kill_interrupts 793
> > [ 54.785007] ath9k_hw_kill_interrupts 793
> > [ 54.792535] ath9k_hw_enable_interrupts 821
> > [ 54.796642] ath9k_hw_enable_interrupts 825
> > [ 54.800807] ath9k_hw_enable_interrupts 832
> > [ 54.804973] AR_SREV_9100 0
> > [ 54.807663] ath9k_hw_enable_interrupts 848
> > [ 54.811843] ath9k_hw_intrpend 762
> > [ 54.815211] (AR_SREV_9340(ah) val 0
> > [ 54.818684] ath9k_hw_intrpend 767
> > [ 54.822078] ath_isr 603
> > [ 54.824587] ath9k_hw_kill_interrupts 793
> > [ 54.828601] ath9k_hw_enable_interrupts 821
> > [ 54.832750] ath9k_hw_enable_interrupts 825
> > [ 54.836916] ath9k_hw_enable_interrupts 832
> > [ 54.841082] AR_SREV_9100 0
> > [ 54.843772] ath9k_hw_enable_interrupts 848
> > [ 54.843775] ath9k_hw_intrpend 762
> > [ 54.851319] (AR_SREV_9340(ah) val 0
> > [ 54.854793] ath9k_hw_intrpend 767
> > [ 54.858185] ath_isr 603
> > [ 54.860696] ath9k_hw_kill_interrupts 793
> > [ 54.864776] ath9k_hw_enable_interrupts 821
> > [ 54.867061] ath9k_hw_kill_interrupts 793
> > [ 54.872870] ath9k_hw_enable_interrupts 825
> > [ 54.877036] ath9k_hw_enable_interrupts 832
> > [ 54.881202] AR_SREV_9100 0
> > [ 54.883892] ath9k_hw_enable_interrupts 848
> > [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> > [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=519
> > [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> > [ 75.982485] Task dump for CPU 0:
> > [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> > [ 75.992726] Call trace:
> > [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> > [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> > [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> > [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=2097
> > [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> > [ 139.078489] Task dump for CPU 0:
> > [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> > [ 139.088731] Call trace:
> > [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> > 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> >
> >
> >> > We are not seeing any issues on 32-bit ARM platform and X86
> >> > platform.
> >>
> >> Can you collect a dmesg log (or, if the system hang means you can't
> >> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> >> output as root? That should have clues about whether the INTx got
> >> routed correctly. /proc/interrupts should also show whether we're
> >> receiving interrupts from the device.
> >
> > Here is the lspci output:
> > 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal
> decode])
> > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> > Latency: 0
> > Interrupt: pin A routed to IRQ 224
> > Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> > I/O behind bridge: 00000000-00000fff
> > Memory behind bridge: e0000000-e00fffff
> > Prefetchable memory behind bridge: 00000000fff00000-
> 00000000000fffff
> > Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- <SERR- <PERR-
> > BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> > PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> > Capabilities: [40] Power Management version 3
> > Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> PME(D0+,D1+,D2+,D3hot+,D3cold-)
> > Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> > Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> > DevCap: MaxPayload 256 bytes, PhantFunc 0
> > ExtTag- RBE+
> > DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> > MaxPayload 128 bytes, MaxReadReq 512 bytes
> > DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend+
> > LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> Exit Latency L0s unlimited, L1 unlimited
> > ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> > LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> > RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> CRSVisible+
> > RootCap: CRSVisible+
> > RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> > DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> OBFF Not Supported ARIFwd-
> > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled ARIFwd-
> > LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> > Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> > Compliance De-emphasis: -6dB
> > LnkSta2: Current De-emphasis Level: -3.5dB,
> EqualizationComplete-, EqualizationPhase1-
> > EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> > Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > Capabilities: [10c v1] Virtual Channel
> > Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > Arb: Fixed- WRR32- WRR64- WRR128-
> > Ctrl: ArbSelect=Fixed
> > Status: InProgress-
> > VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> > Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > Status: NegoPending- InProgress-
> > Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1
> > Len=018 <?>
> >
> > 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network
> Adapter (rev 01)
> > Subsystem: Qualcomm Atheros Device 3112
> > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> > Latency: 0, Cache Line Size: 128 bytes
> > Interrupt: pin A routed to IRQ 224
> > Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> > [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> > Capabilities: [40] Power Management version 3
> > Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> PME(D0+,D1+,D2-,D3hot+,D3cold-)
> > Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> > Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> > Address: 0000000000000000 Data: 0000
> > Masking: 00000000 Pending: 00000000
> > Capabilities: [70] Express (v2) Endpoint, MSI 00
> > DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> L0s <1us, L1 <8us
> > ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> SlotPowerLimit 0.000W
> > DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> > MaxPayload 128 bytes, MaxReadReq 512 bytes
> > DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend-
> > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> Latency L0s <2us, L1 <64us
> > ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> > LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> > DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> LTR-, OBFF Not Supported
> > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled
> > LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> SpeedDis-
> > Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> > Compliance De-emphasis: -6dB
> > LnkSta2: Current De-emphasis Level: -6dB,
> EqualizationComplete-, EqualizationPhase1-
> > EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> > Capabilities: [100 v1] Advanced Error Reporting
> > UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> > CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr-
> > CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr+
> > AERCap: First Error Pointer: 00, GenCap- CGenEn-
> ChkCap- ChkEn-
> > Capabilities: [140 v1] Virtual Channel
> > Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > Arb: Fixed- WRR32- WRR64- WRR128-
> > Ctrl: ArbSelect=Fixed
> > Status: InProgress-
> > VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> > Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > Status: NegoPending- InProgress-
> > Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > Kernel driver in use: ath9k
> >
> > Here is the cat /proc/interrupts (after we do interface up):
> >
> > root@:~# ifconfig wlan0 up
> > [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> > root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > CPU0 CPU1 CPU2 CPU3
> > 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> > 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP,
> Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
> > 218: 61 0 0 0 GICv2 81 Level mmc0
> > 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> > 220: 471 0 0 0 GICv2 53 Level xuartps
> > 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > 224: 3 0 0 0 dummy 1 Edge ath9k
> > 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> >
> > Regards,
> > Bharat
>
> --
> Kalle Valo

2016-12-09 06:55:40

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

Sorry, Forgot to add kernel version, we are using 4.6 kernel.

> Hi,
> Can any one tell, when exactly the chip sends ASSERT & DEASSERT in driver.
> It might help us to debug issue further.
>
> Thanks & Regards,
> Bharat
>
> > > > [+cc Kalle, ath9k list]
> >
> > Thanks, but please also CC linux-wireless. Full thread below for the folks there.
> >
> > >> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> > >> > Hi,
> > >> >
> > >> > Did anyone test Atheros ATH9
> > >> > driver(drivers/net/wireless/ath/ath9k/)
> > >> > on ARM64. The end point is TP link wifi card with which supports
> > >> > only legacy interrupts.
> > >>
> > >> If it works on other arches and the arm64 PCI enumeration works, my
> > >> first guess would be an INTx issue, e.g., maybe the driver is
> > >> waiting for an interrupt that never arrives.
> > > We are not sure for now.
> > >>
> > >> > We are trying to test it on ARM64 with
> > >> > (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> > >> >
> > >> > EP is getting enumerated and able to link up.
> > >> >
> > >> > But when we start scan system gets hanged.
> > >>
> > >> When you say the system hangs when you start a scan, I assume you
> > >> mean a wifi scan, not the PCI enumeration. A problem with a wifi
> > >> scan might cause a *process* to hang, but it shouldn't hang the
> > >> entire system.
> > >>
> > > Yes wifi scan.
> > >> > When we took trace we see that after we start scan assert message
> > >> > is sent but there is no de assert from end point.
> > >>
> > >> Are you talking about a trace from a PCIe analyzer? Do you see an
> > >> Assert_INTx PCIe message on the link?
> > >>
> > > Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx
> > > happening
> > when we do interface link up.
> > > When we have less debug prints in Atheros driver, and do wifi scan
> > > we see Assert_INTx but never Deassert_INTx,
> > >> > What might cause end point not sending de assert ?
> > >>
> > >> If the endpoint doesn't send a Deassert_INTx message, I expect that
> > >> would mean the driver didn't service the interrupt and remove the
> > >> condition that caused the device to assert the interrupt in the
> > >> first place.
> > >>
> > >> If the driver didn't receive the interrupt, it couldn't service it,
> > >> of course. You could add a printk in the ath9k interrupt service
> > >> routine to see if you ever get there.
> > >>
> > > The interrupt behavior is changing w.r.t amount of debug prints we
> > > add. (I kept many prints to aid debug) root@Xilinx-ZCU102-2016_3:~#
> > > iw dev
> > wlan0 scan
> > > [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.074257] ath9k_hw_kill_interrupts 793
> > > [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.087882] ath9k_hw_kill_interrupts 793
> > > [ 83.095450] ath9k_hw_enable_interrupts 821
> > > [ 83.099557] ath9k_hw_enable_interrupts 825
> > > [ 83.103721] ath9k_hw_enable_interrupts 832
> > > [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.112748] AR_SREV_9100 0
> > > [ 83.115438] ath9k_hw_enable_interrupts 848
> > > [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.124389] ath9k_hw_intrpend 762
> > > [ 83.127761] (AR_SREV_9340(ah) val 0
> > > [ 83.131234] ath9k_hw_intrpend 767
> > > [ 83.134628] ath_isr 603
> > > [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.146771] ath9k_hw_kill_interrupts 793
> > > [ 83.150864] ath9k_hw_enable_interrupts 821
> > > [ 83.154971] ath9k_hw_enable_interrupts 825
> > > [ 83.159135] ath9k_hw_enable_interrupts 832
> > > [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.168161] AR_SREV_9100 0
> > > [ 83.170852] ath9k_hw_enable_interrupts 848
> > > [ 83.170855] ath9k_hw_intrpend 762
> > > [ 83.178398] (AR_SREV_9340(ah) val 0
> > > [ 83.181873] ath9k_hw_intrpend 767
> > > [ 83.185265] ath_isr 603
> > > [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.197411] ath9k_hw_kill_interrupts 793
> > > [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.206258] ath9k_hw_enable_interrupts 821
> > > [ 83.210368] ath9k_hw_enable_interrupts 825
> > > [ 83.214531] ath9k_hw_enable_interrupts 832
> > > [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.223558] AR_SREV_9100 0
> > > [ 83.226243] ath9k_hw_enable_interrupts 848
> > > [ 83.226246] ath9k_hw_intrpend 762
> > > [ 83.233794] (AR_SREV_9340(ah) val 0
> > > [ 83.237268] ath9k_hw_intrpend 767
> > > [ 83.240661] ath_isr 603
> > > [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.252806] ath9k_hw_kill_interrupts 793
> > > [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.261651] ath9k_hw_enable_interrupts 821
> > > [ 83.265753] ath9k_hw_enable_interrupts 825
> > > [ 83.269919] ath9k_hw_enable_interrupts 832
> > > [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.278945] AR_SREV_9100 0
> > > [ 83.281630] ath9k_hw_enable_interrupts 848
> > > [ 83.281633] ath9k_hw_intrpend 762
> > > [ 83.281634] (AR_SREV_9340(ah) val 0
> > > [ 83.281637] ath9k_hw_intrpend 767
> > > [ 83.281648] ath_isr 603
> > > [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.281654] ath9k_hw_kill_interrupts 793
> > > [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> > > [ 83.317030] ath9k_hw_enable_interrupts 821
> > > [ 83.321132] ath9k_hw_enable_interrupts 825
> > > [ 83.325297] ath9k_hw_enable_interrupts 832
> > > [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> > > [ 83.334324] AR_SREV_9100 0
> > > [ 83.337014] ath9k_hw_enable_interrupts 848
> > > ..
> > > ..
> > > This log continues until I turn off board without obtaining scanning result.
> > >
> > > In between I get following cpu stall outputs :
> > > 230.457179] INFO: rcu_sched self-detected stall on CPU
> > > [ 230.457185] 2-...: (31314 ticks this GP)
> > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> > > [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> > > [ 230.457191] Task dump for CPU 2:
> > > [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> > > [ 230.457207] Workqueue: phy0 ieee80211_scan_work [ 230.457208]
> > > Call
> > > trace:
> > > [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> > > 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [ 230.457224]
> > > [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [ 230.457228]
> > > [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [ 230.457233]
> > > [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0 [ 230.457239]
> > > [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748 [ 230.457243]
> > > [<ffffff80080e7cfc>] update_process_times+0x3c/0x68 [ 230.457249]
> > > [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> > > [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90 [
> > > 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> > > ** 10 printk messages dropped ** [ 230.457302] f8c0:
> > > 0000000000000000 0000000005f5e0ff 000000000001379a
> 3866666666666620
> > > [ 230.457306]
> > > f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000
> > > ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> > > ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [ 230.457314]
> > > f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> > > ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> > > ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [ 230.457322]
> > > f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> > > 0000000060000145
> > > ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>]
> > > el1_irq+0xa0/0x100
> > > ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>]
> > > ieee80211_hw_config+0x50/0x290 [ 230.457377] [<ffffff8008863690>]
> > > ieee80211_scan_work+0x1f8/0x480 [ 230.457383] [<ffffff80080b15d0>]
> > > process_one_work+0x120/0x378 [ 230.457386] [<ffffff80080b1870>]
> > > worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> > > kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> > ret_from_fork+0x10/0x40
> > > [ 230.480389] ath9k_hw_intrpend 762
> > >
> > >
> > > [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [ 545.526189]
> > > INFO: rcu_sched self-detected stall on CPU
> > > [ 545.526195] 2-...: (97636 ticks this GP)
> > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> > > [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> > > [ 545.526201] Task dump for CPU 2:
> > > [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> > > ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>]
> > > show_stack+0x14/0x20
> > > ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>]
> > > arch_timer_handler_phys+0x30/0x40 [ 545.526284]
> > > [<ffffff80080dbe18>]
> > > handle_percpu_devid_irq+0x78/0xa0 [ 545.526291]
> > > [<ffffff80080d760c>]
> > > generic_handle_irq+0x24/0x38 [ 545.526296] [<ffffff80080d7944>]
> > > __handle_domain_irq+0x5c/0xb8 [ 545.526299] [<ffffff80080824bc>]
> > > gic_handle_irq+0x64/0xc0 [ 545.526302] Exception
> > > stack(0xffffffc87b07f870
> > to 0xffffffc87b07f990)
> > > [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> > > ** 8 printk messages dropped ** [ 545.526341] f980:
> > > ffffff800a1c39e8
> > > 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> > > el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> > > console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> > > vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> > > vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> > > printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> > > ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> > > ath9k_hw_kill_interrupts+0x28/0xf0
> > > [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> > > ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>]
> > ieee80211_hw_config+0x50/0x290
> > > ** 11 printk messages dropped ** [ 545.532834]
> > > ath9k_hw_kill_interrupts
> > 793
> > > [ 545.532890] ath9k_hw_enable_interrupts 821
> > >
> > >
> > > But if we have less debug prints it does not reach EP handler
> > > sometimes, due to following Condition in "kernel/irq/chip.c" in
> > > function handle_simple_irq
> > >
> > > if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> > > desc->istate |= IRQS_PENDING;
> > > goto out_unlock;
> > > }
> > > Here irqd_irq_disabled is being set to 1.
> > >
> > > With lesser debug prints it stops after following prints:
> > > root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> > > [ 54.781045] ath9k_hw_kill_interrupts 793
> > > [ 54.785007] ath9k_hw_kill_interrupts 793
> > > [ 54.792535] ath9k_hw_enable_interrupts 821
> > > [ 54.796642] ath9k_hw_enable_interrupts 825
> > > [ 54.800807] ath9k_hw_enable_interrupts 832
> > > [ 54.804973] AR_SREV_9100 0
> > > [ 54.807663] ath9k_hw_enable_interrupts 848
> > > [ 54.811843] ath9k_hw_intrpend 762
> > > [ 54.815211] (AR_SREV_9340(ah) val 0
> > > [ 54.818684] ath9k_hw_intrpend 767
> > > [ 54.822078] ath_isr 603
> > > [ 54.824587] ath9k_hw_kill_interrupts 793
> > > [ 54.828601] ath9k_hw_enable_interrupts 821
> > > [ 54.832750] ath9k_hw_enable_interrupts 825
> > > [ 54.836916] ath9k_hw_enable_interrupts 832
> > > [ 54.841082] AR_SREV_9100 0
> > > [ 54.843772] ath9k_hw_enable_interrupts 848
> > > [ 54.843775] ath9k_hw_intrpend 762
> > > [ 54.851319] (AR_SREV_9340(ah) val 0
> > > [ 54.854793] ath9k_hw_intrpend 767
> > > [ 54.858185] ath_isr 603
> > > [ 54.860696] ath9k_hw_kill_interrupts 793
> > > [ 54.864776] ath9k_hw_enable_interrupts 821
> > > [ 54.867061] ath9k_hw_kill_interrupts 793
> > > [ 54.872870] ath9k_hw_enable_interrupts 825
> > > [ 54.877036] ath9k_hw_enable_interrupts 832
> > > [ 54.881202] AR_SREV_9100 0
> > > [ 54.883892] ath9k_hw_enable_interrupts 848
> > > [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > softirq=1103/1109 fqs=519
> > > [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> > > [ 75.982485] Task dump for CPU 0:
> > > [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > [ 75.992726] Call trace:
> > > [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> > > [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> > > [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > softirq=1103/1109 fqs=2097
> > > [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> > > [ 139.078489] Task dump for CPU 0:
> > > [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > [ 139.088731] Call trace:
> > > [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> > > 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> > >
> > >
> > >> > We are not seeing any issues on 32-bit ARM platform and X86
> > >> > platform.
> > >>
> > >> Can you collect a dmesg log (or, if the system hang means you can't
> > >> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> > >> output as root? That should have clues about whether the INTx got
> > >> routed correctly. /proc/interrupts should also show whether we're
> > >> receiving interrupts from the device.
> > >
> > > Here is the lspci output:
> > > 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00
> > > [Normal
> > decode])
> > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > Latency: 0
> > > Interrupt: pin A routed to IRQ 224
> > > Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> > > I/O behind bridge: 00000000-00000fff
> > > Memory behind bridge: e0000000-e00fffff
> > > Prefetchable memory behind bridge: 00000000fff00000-
> > 00000000000fffff
> > > Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- <SERR- <PERR-
> > > BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> > > PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> > > Capabilities: [40] Power Management version 3
> > > Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> > PME(D0+,D1+,D2+,D3hot+,D3cold-)
> > > Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> > > Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> > > DevCap: MaxPayload 256 bytes, PhantFunc 0
> > > ExtTag- RBE+
> > > DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > Unsupported-
> > > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> > > MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > TransPend+
> > > LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> > Exit Latency L0s unlimited, L1 unlimited
> > > ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> > > LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > > LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > DLActive- BWMgmt- ABWMgmt-
> > > RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> > CRSVisible+
> > > RootCap: CRSVisible+
> > > RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> > > DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> > OBFF Not Supported ARIFwd-
> > > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > OBFF Disabled ARIFwd-
> > > LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> > > Transmit Margin: Normal Operating Range,
> > EnterModifiedCompliance- ComplianceSOS-
> > > Compliance De-emphasis: -6dB
> > > LnkSta2: Current De-emphasis Level: -3.5dB,
> > EqualizationComplete-, EqualizationPhase1-
> > > EqualizationPhase2-, EqualizationPhase3-,
> > LinkEqualizationRequest-
> > > Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > > Capabilities: [10c v1] Virtual Channel
> > > Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > Arb: Fixed- WRR32- WRR64- WRR128-
> > > Ctrl: ArbSelect=Fixed
> > > Status: InProgress-
> > > VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > > Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > WRR256-
> > > Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > Status: NegoPending- InProgress-
> > > Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1
> > > Len=018 <?>
> > >
> > > 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network
> > Adapter (rev 01)
> > > Subsystem: Qualcomm Atheros Device 3112
> > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > Latency: 0, Cache Line Size: 128 bytes
> > > Interrupt: pin A routed to IRQ 224
> > > Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> > > [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> > > Capabilities: [40] Power Management version 3
> > > Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> > PME(D0+,D1+,D2-,D3hot+,D3cold-)
> > > Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> > > Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> > > Address: 0000000000000000 Data: 0000
> > > Masking: 00000000 Pending: 00000000
> > > Capabilities: [70] Express (v2) Endpoint, MSI 00
> > > DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> > L0s <1us, L1 <8us
> > > ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> > SlotPowerLimit 0.000W
> > > DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > Unsupported-
> > > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> > > MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > TransPend-
> > > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> > Latency L0s <2us, L1 <64us
> > > ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> > > LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > > LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > DLActive- BWMgmt- ABWMgmt-
> > > DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> > LTR-, OBFF Not Supported
> > > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > OBFF Disabled
> > > LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> > SpeedDis-
> > > Transmit Margin: Normal Operating Range,
> > EnterModifiedCompliance- ComplianceSOS-
> > > Compliance De-emphasis: -6dB
> > > LnkSta2: Current De-emphasis Level: -6dB,
> > EqualizationComplete-, EqualizationPhase1-
> > > EqualizationPhase2-, EqualizationPhase3-,
> > LinkEqualizationRequest-
> > > Capabilities: [100 v1] Advanced Error Reporting
> > > UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> > > CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > NonFatalErr-
> > > CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > NonFatalErr+
> > > AERCap: First Error Pointer: 00, GenCap- CGenEn-
> > ChkCap- ChkEn-
> > > Capabilities: [140 v1] Virtual Channel
> > > Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > Arb: Fixed- WRR32- WRR64- WRR128-
> > > Ctrl: ArbSelect=Fixed
> > > Status: InProgress-
> > > VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > > Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > WRR256-
> > > Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > Status: NegoPending- InProgress-
> > > Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > > Kernel driver in use: ath9k
> > >
> > > Here is the cat /proc/interrupts (after we do interface up):
> > >
> > > root@:~# ifconfig wlan0 up
> > > [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> > > root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > > CPU0 CPU1 CPU2 CPU3
> > > 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > > 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> > > 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > > 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > > 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > > 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > > 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > > 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > > 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > > 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > > 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> Mali_GP,
> > Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > > 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > > 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > > 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > > 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > > 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > > 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > > 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > > 217: 0 0 0 0 GICv2 165 Level ahci-
> ceva[fd0c0000.ahci]
> > > 218: 61 0 0 0 GICv2 81 Level mmc0
> > > 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> > > 220: 471 0 0 0 GICv2 53 Level xuartps
> > > 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > > 224: 3 0 0 0 dummy 1 Edge ath9k
> > > 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> > >
> > > Regards,
> > > Bharat
> >
> > --
> > Kalle Valo
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of
> a message to [email protected] More majordomo info at
> http://vger.kernel.org/majordomo-info.html

2016-12-09 10:50:44

by Marc Zyngier

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

On 09/12/16 02:07, Bharat Kumar Gogada wrote:
>> On 08/12/16 18:33, Bharat Kumar Gogada wrote:
>>>> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
>>>>> 218: 61 0 0 0 GICv2 81 Level mmc0
>>>>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
>>>>> 220: 471 0 0 0 GICv2 53 Level xuartps
>>>>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
>>>>> 224: 3 0 0 0 dummy 1 Edge ath9k
>>>>
>>>> What is this "dummy" controller? And if that's supposed to be a
>>>> legacy interrupt from the PCI device, it has the wrong trigger.
>>>
>>> Yes it is for legacy interrupt, wrong trigger means ?
>>
>> Aren't legacy interrupts supposed to be *level* triggered, and not edge?
>>
> Yes agreed.
> For legacy interrupts im using irq_set_chained_handler_and_data so the irq line between bridge and GIC
> Will not be shown here. The above how is virq for legacy, which is given by kernel, not sure why its state is set
> to edge.

Well, you should try and find out. Edge triggering for legacy interrupts
is a real bug, and I don't think it has anything to do with arm64
(despite what the subject says).

Thanks,

M.
--
Jazz is not dead. It just smells funny...

2016-12-09 11:04:19

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> On 09/12/16 02:07, Bharat Kumar Gogada wrote:
> >> On 08/12/16 18:33, Bharat Kumar Gogada wrote:
> >>>> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
> >>>>> 218: 61 0 0 0 GICv2 81 Level mmc0
> >>>>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global
> fault
> >>>>> 220: 471 0 0 0 GICv2 53 Level xuartps
> >>>>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> >>>>> 224: 3 0 0 0 dummy 1 Edge ath9k
> >>>>
> >>>> What is this "dummy" controller? And if that's supposed to be a
> >>>> legacy interrupt from the PCI device, it has the wrong trigger.
> >>>
> >>> Yes it is for legacy interrupt, wrong trigger means ?
> >>
> >> Aren't legacy interrupts supposed to be *level* triggered, and not edge?
> >>
> > Yes agreed.
> > For legacy interrupts im using irq_set_chained_handler_and_data so the
> > irq line between bridge and GIC Will not be shown here. The above how
> > is virq for legacy, which is given by kernel, not sure why its state is set to edge.
>
> Well, you should try and find out. Edge triggering for legacy interrupts is a real
> bug, and I don't think it has anything to do with arm64 (despite what the subject
> says).
>
Thanks Marc. Here is the ARM32 bit log for cat /proc/interrupts,
Here also it shows edge but still scan works successfully.
root@:~#cat /proc/interrupts
CPU0 CPU1
16: 1 0 GIC-0 27 Edge gt
17: 0 0 GIC-0 43 Level ttc_clockevent
18: 3049 1170 GIC-0 29 Edge twd
21: 43 0 GIC-0 39 Level f8007100.adc
141: 462 0 GIC-0 57 Level cdns-i2c
143: 0 0 GIC-0 35 Level f800c000.ocmc
144: 1259 0 GIC-0 82 Level xuartps
145: 3 0 GIC-0 51 Level e000d000.spi
146: 0 0 GIC-0 54 Level eth0
147: 54 0 GIC-0 56 Level mmc0
148: 0 0 GIC-0 45 Level f8003000.dmac
149: 0 0 GIC-0 46 Level f8003000.dmac
150: 0 0 GIC-0 47 Level f8003000.dmac
151: 0 0 GIC-0 48 Level f8003000.dmac
152: 0 0 GIC-0 49 Level f8003000.dmac
153: 0 0 GIC-0 72 Level f8003000.dmac
154: 0 0 GIC-0 73 Level f8003000.dmac
155: 0 0 GIC-0 74 Level f8003000.dmac
156: 0 0 GIC-0 75 Level f8003000.dmac
157: 0 0 GIC-0 40 Level f8007000.devcfg
163: 0 0 GIC-0 53 Level e0002000.usb
164: 0 0 GIC-0 41 Edge f8005000.watchdog
165: 158 0 GIC-0 61 Level xilinx-pcie
166: 122 18 dummy 1 Edge ath9k
IPI1: 0 0 Timer broadcast interrupts
IPI2: 1101 2349 Rescheduling interrupts
IPI3: 34 20 Function call interrupts
IPI4: 0 0 CPU stop interrupts
IPI5: 0 0 IRQ work interrupts
IPI6: 0 0 completion interrupts

root@Xilinx-ZC706-2016_3:~# iw dev wlnan0 scan
BSS d8:c7:c8:26:6a:72(on wlan0)
TSF: 349496494967 usec (4d, 01:04:56)
freq: 2412
beacon interval: 100 TUs
capability: ESS ShortPreamble ShortSlotTime (0x0421)
signal: -47.00 dBm
last seen: 2170 ms ago
.....
....

Thanks & Regards,
Bharat

2016-12-09 11:24:05

by Marc Zyngier

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

On 09/12/16 11:04, Bharat Kumar Gogada wrote:
>> On 09/12/16 02:07, Bharat Kumar Gogada wrote:
>>>> On 08/12/16 18:33, Bharat Kumar Gogada wrote:
>>>>>> On 08/12/16 15:29, Bharat Kumar Gogada wrote:
>>>>>>> 218: 61 0 0 0 GICv2 81 Level mmc0
>>>>>>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global
>> fault
>>>>>>> 220: 471 0 0 0 GICv2 53 Level xuartps
>>>>>>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
>>>>>>> 224: 3 0 0 0 dummy 1 Edge ath9k
>>>>>>
>>>>>> What is this "dummy" controller? And if that's supposed to be a
>>>>>> legacy interrupt from the PCI device, it has the wrong trigger.
>>>>>
>>>>> Yes it is for legacy interrupt, wrong trigger means ?
>>>>
>>>> Aren't legacy interrupts supposed to be *level* triggered, and not edge?
>>>>
>>> Yes agreed.
>>> For legacy interrupts im using irq_set_chained_handler_and_data so the
>>> irq line between bridge and GIC Will not be shown here. The above how
>>> is virq for legacy, which is given by kernel, not sure why its state is set to edge.
>>
>> Well, you should try and find out. Edge triggering for legacy interrupts is a real
>> bug, and I don't think it has anything to do with arm64 (despite what the subject
>> says).
>>
> Thanks Marc. Here is the ARM32 bit log for cat /proc/interrupts,
> Here also it shows edge but still scan works successfully.

Because it works doesn't mean it is right.

Thanks,

M.
--
Jazz is not dead. It just smells funny...

2016-12-09 14:22:45

by Tobias Klausmann

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

Hello there,

as this is a thread about ath9k and ARM64, i'm not sure if i should
answer here or not, but i have similar "stalls" with ath9k on x86_64
(starting with 4.9rc), stack trace is posted down below where the
original ARM64 stall traces are.

Greetings,

Tobias


On 08.12.2016 18:36, Kalle Valo wrote:
> Bharat Kumar Gogada <[email protected]> writes:
>
>> > [+cc Kalle, ath9k list]
> Thanks, but please also CC linux-wireless. Full thread below for the
> folks there.
>
>>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
>>>> Hi,
>>>>
>>>> Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/)
>>>> on ARM64. The end point is TP link wifi card with which supports
>>>> only legacy interrupts.
>>> If it works on other arches and the arm64 PCI enumeration works, my
>>> first guess would be an INTx issue, e.g., maybe the driver is waiting
>>> for an interrupt that never arrives.
>> We are not sure for now.
>>>> We are trying to test it on ARM64 with
>>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
>>>>
>>>> EP is getting enumerated and able to link up.
>>>>
>>>> But when we start scan system gets hanged.
>>> When you say the system hangs when you start a scan, I assume you mean
>>> a wifi scan, not the PCI enumeration. A problem with a wifi scan
>>> might cause a *process* to hang, but it shouldn't hang the entire
>>> system.
>>>
>> Yes wifi scan.
>>>> When we took trace we see that after we start scan assert message is
>>>> sent but there is no de assert from end point.
>>> Are you talking about a trace from a PCIe analyzer? Do you see an
>>> Assert_INTx PCIe message on the link?
>>>
>> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening when we do interface link up.
>> When we have less debug prints in Atheros driver, and do wifi scan we see Assert_INTx but never Deassert_INTx,
>>>> What might cause end point not sending de assert ?
>>> If the endpoint doesn't send a Deassert_INTx message, I expect that
>>> would mean the driver didn't service the interrupt and remove the
>>> condition that caused the device to assert the interrupt in the first
>>> place.
>>>
>>> If the driver didn't receive the interrupt, it couldn't service it, of
>>> course. You could add a printk in the ath9k interrupt service
>>> routine to see if you ever get there.
>>>
>> The interrupt behavior is changing w.r.t amount of debug prints we add. (I kept many prints to aid debug)
>> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
>> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.074257] ath9k_hw_kill_interrupts 793
>> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.087882] ath9k_hw_kill_interrupts 793
>> [ 83.095450] ath9k_hw_enable_interrupts 821
>> [ 83.099557] ath9k_hw_enable_interrupts 825
>> [ 83.103721] ath9k_hw_enable_interrupts 832
>> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.112748] AR_SREV_9100 0
>> [ 83.115438] ath9k_hw_enable_interrupts 848
>> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.124389] ath9k_hw_intrpend 762
>> [ 83.127761] (AR_SREV_9340(ah) val 0
>> [ 83.131234] ath9k_hw_intrpend 767
>> [ 83.134628] ath_isr 603
>> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.146771] ath9k_hw_kill_interrupts 793
>> [ 83.150864] ath9k_hw_enable_interrupts 821
>> [ 83.154971] ath9k_hw_enable_interrupts 825
>> [ 83.159135] ath9k_hw_enable_interrupts 832
>> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.168161] AR_SREV_9100 0
>> [ 83.170852] ath9k_hw_enable_interrupts 848
>> [ 83.170855] ath9k_hw_intrpend 762
>> [ 83.178398] (AR_SREV_9340(ah) val 0
>> [ 83.181873] ath9k_hw_intrpend 767
>> [ 83.185265] ath_isr 603
>> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.197411] ath9k_hw_kill_interrupts 793
>> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.206258] ath9k_hw_enable_interrupts 821
>> [ 83.210368] ath9k_hw_enable_interrupts 825
>> [ 83.214531] ath9k_hw_enable_interrupts 832
>> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.223558] AR_SREV_9100 0
>> [ 83.226243] ath9k_hw_enable_interrupts 848
>> [ 83.226246] ath9k_hw_intrpend 762
>> [ 83.233794] (AR_SREV_9340(ah) val 0
>> [ 83.237268] ath9k_hw_intrpend 767
>> [ 83.240661] ath_isr 603
>> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.252806] ath9k_hw_kill_interrupts 793
>> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.261651] ath9k_hw_enable_interrupts 821
>> [ 83.265753] ath9k_hw_enable_interrupts 825
>> [ 83.269919] ath9k_hw_enable_interrupts 832
>> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.278945] AR_SREV_9100 0
>> [ 83.281630] ath9k_hw_enable_interrupts 848
>> [ 83.281633] ath9k_hw_intrpend 762
>> [ 83.281634] (AR_SREV_9340(ah) val 0
>> [ 83.281637] ath9k_hw_intrpend 767
>> [ 83.281648] ath_isr 603
>> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.281654] ath9k_hw_kill_interrupts 793
>> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 83.317030] ath9k_hw_enable_interrupts 821
>> [ 83.321132] ath9k_hw_enable_interrupts 825
>> [ 83.325297] ath9k_hw_enable_interrupts 832
>> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
>> [ 83.334324] AR_SREV_9100 0
>> [ 83.337014] ath9k_hw_enable_interrupts 848
>> ..
>> ..
>> This log continues until I turn off board without obtaining scanning result.
>>
>> In between I get following cpu stall outputs :
>> 230.457179] INFO: rcu_sched self-detected stall on CPU
>> [ 230.457185] 2-...: (31314 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
>> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
>> [ 230.457191] Task dump for CPU 2:
>> [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
>> [ 230.457207] Workqueue: phy0 ieee80211_scan_work
>> [ 230.457208] Call trace:
>> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198
>> [ 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20
>> [ 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8
>> [ 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50
>> [ 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0
>> [ 230.457239] [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748
>> [ 230.457243] [<ffffff80080e7cfc>] update_process_times+0x3c/0x68
>> [ 230.457249] [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
>> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90
>> [ 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
>> ** 10 printk messages dropped ** [ 230.457302] f8c0: 0000000000000000 0000000005f5e0ff 000000000001379a 3866666666666620
>> [ 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000 ffffffc87b8010a8
>> [ 230.457310] f900: ffffff808a1b4057 ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000
>> [ 230.457314] f920: 0000000000000140 0000000000000006 ffffff800a1b3b10 ffffff800a1c39e8
>> [ 230.457318] f940: 000000000000002f ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990
>> [ 230.457322] f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234 0000000060000145
>> ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>] el1_irq+0xa0/0x100
>> ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
>> [ 230.457377] [<ffffff8008863690>] ieee80211_scan_work+0x1f8/0x480
>> [ 230.457383] [<ffffff80080b15d0>] process_one_work+0x120/0x378
>> [ 230.457386] [<ffffff80080b1870>] worker_thread+0x48/0x4b0
>> [ 230.457391] [<ffffff80080b7108>] kthread+0xd0/0xe8
>> [ 230.457395] [<ffffff8008085dd0>] ret_from_fork+0x10/0x40
>> [ 230.480389] ath9k_hw_intrpend 762
>>
>>
>> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024
>> [ 545.526189] INFO: rcu_sched self-detected stall on CPU
>> [ 545.526195] 2-...: (97636 ticks this GP) idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
>> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
>> [ 545.526201] Task dump for CPU 2:
>> [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
>> ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>] show_stack+0x14/0x20
>> ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>] arch_timer_handler_phys+0x30/0x40
>> [ 545.526284] [<ffffff80080dbe18>] handle_percpu_devid_irq+0x78/0xa0
>> [ 545.526291] [<ffffff80080d760c>] generic_handle_irq+0x24/0x38
>> [ 545.526296] [<ffffff80080d7944>] __handle_domain_irq+0x5c/0xb8
>> [ 545.526299] [<ffffff80080824bc>] gic_handle_irq+0x64/0xc0
>> [ 545.526302] Exception stack(0xffffffc87b07f870 to 0xffffffc87b07f990)
>> [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
>> ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8 0000000000000036
>> [ 545.526345] [<ffffff8008085720>] el1_irq+0xa0/0x100
>> [ 545.526349] [<ffffff80080d6234>] console_unlock+0x384/0x5b0
>> [ 545.526353] [<ffffff80080d673c>] vprintk_emit+0x2dc/0x4b0
>> [ 545.526357] [<ffffff80080d6a50>] vprintk_default+0x38/0x40
>> [ 545.526362] [<ffffff8008129704>] printk+0x58/0x60
>> [ 545.526366] [<ffffff800859e3e4>] ath9k_iowrite32+0x9c/0xa8
>> [ 545.526372] [<ffffff80085c7ca8>] ath9k_hw_kill_interrupts+0x28/0xf0
>> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
>> ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>] ieee80211_hw_config+0x50/0x290
>> ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts 793
>> [ 545.532890] ath9k_hw_enable_interrupts 821

[ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
[ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
[ 81.876936] swapper/4 R running task 0 0 1
0x00000000
[ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
ffffffff81a3dc40
[ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
ffffffff81a3dc40
[ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
ffff88017edbc240
[ 81.876951] Call Trace:
[ 81.876970] <IRQ>
[ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
[ 81.876983] [<ffffffff81101e46>] ?
rcu_print_detail_task_stall_rnp+0x40/0x61
[ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
[ 81.876993] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
[ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
[ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
[ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
[ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
[ 81.877008] [<ffffffff81031b1e>] ?
smp_trace_apic_timer_interrupt+0x5e/0x90
[ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
[ 81.877013] <EOI>
[ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
[ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
[ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
[ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
[ 81.877029] swapper/4 R running task 0 0 1
0x00000000
[ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
ffffffff81a3dc40
[ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
ffffffff81a3dc40
[ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
ffff88017edbc240
[ 81.877041] Call Trace:
[ 81.877045] <IRQ>
[ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
[ 81.877051] [<ffffffff81101e46>] ?
rcu_print_detail_task_stall_rnp+0x40/0x61
[ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
[ 81.877058] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
[ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
[ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
[ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
[ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
[ 81.877070] [<ffffffff81031b1e>] ?
smp_trace_apic_timer_interrupt+0x5e/0x90
[ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
[ 81.877074] <EOI>
[ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
[ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
[ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
[ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
[ 91.132787] INFO: rcu_preempt detected expedited stalls on
CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
[ 91.132796] blocking rcu_node structures:

>>
>>
>> But if we have less debug prints it does not reach EP handler sometimes, due to following
>> Condition in "kernel/irq/chip.c" in function handle_simple_irq
>>
>> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
>> desc->istate |= IRQS_PENDING;
>> goto out_unlock;
>> }
>> Here irqd_irq_disabled is being set to 1.
>>
>> With lesser debug prints it stops after following prints:
>> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
>> [ 54.781045] ath9k_hw_kill_interrupts 793
>> [ 54.785007] ath9k_hw_kill_interrupts 793
>> [ 54.792535] ath9k_hw_enable_interrupts 821
>> [ 54.796642] ath9k_hw_enable_interrupts 825
>> [ 54.800807] ath9k_hw_enable_interrupts 832
>> [ 54.804973] AR_SREV_9100 0
>> [ 54.807663] ath9k_hw_enable_interrupts 848
>> [ 54.811843] ath9k_hw_intrpend 762
>> [ 54.815211] (AR_SREV_9340(ah) val 0
>> [ 54.818684] ath9k_hw_intrpend 767
>> [ 54.822078] ath_isr 603
>> [ 54.824587] ath9k_hw_kill_interrupts 793
>> [ 54.828601] ath9k_hw_enable_interrupts 821
>> [ 54.832750] ath9k_hw_enable_interrupts 825
>> [ 54.836916] ath9k_hw_enable_interrupts 832
>> [ 54.841082] AR_SREV_9100 0
>> [ 54.843772] ath9k_hw_enable_interrupts 848
>> [ 54.843775] ath9k_hw_intrpend 762
>> [ 54.851319] (AR_SREV_9340(ah) val 0
>> [ 54.854793] ath9k_hw_intrpend 767
>> [ 54.858185] ath_isr 603
>> [ 54.860696] ath9k_hw_kill_interrupts 793
>> [ 54.864776] ath9k_hw_enable_interrupts 821
>> [ 54.867061] ath9k_hw_kill_interrupts 793
>> [ 54.872870] ath9k_hw_enable_interrupts 825
>> [ 54.877036] ath9k_hw_enable_interrupts 832
>> [ 54.881202] AR_SREV_9100 0
>> [ 54.883892] ath9k_hw_enable_interrupts 848
>> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
>> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=519
>> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
>> [ 75.982485] Task dump for CPU 0:
>> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
>> [ 75.992726] Call trace:
>> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
>> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
>> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
>> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0 softirq=1103/1109 fqs=2097
>> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
>> [ 139.078489] Task dump for CPU 0:
>> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
>> [ 139.088731] Call trace:
>> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
>> [ 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
>>
>>
>>>> We are not seeing any issues on 32-bit ARM platform and X86
>>>> platform.
>>> Can you collect a dmesg log (or, if the system hang means you can't
>>> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
>>> output as root? That should have clues about whether the INTx got
>>> routed correctly. /proc/interrupts should also show whether we're
>>> receiving interrupts from the device.
>> Here is the lspci output:
>> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal decode])
>> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
>> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>> Latency: 0
>> Interrupt: pin A routed to IRQ 224
>> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
>> I/O behind bridge: 00000000-00000fff
>> Memory behind bridge: e0000000-e00fffff
>> Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
>> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
>> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
>> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
>> Capabilities: [40] Power Management version 3
>> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
>> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
>> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
>> DevCap: MaxPayload 256 bytes, PhantFunc 0
>> ExtTag- RBE+
>> DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
>> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
>> MaxPayload 128 bytes, MaxReadReq 512 bytes
>> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend+
>> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported, Exit Latency L0s unlimited, L1 unlimited
>> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
>> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
>> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
>> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible+
>> RootCap: CRSVisible+
>> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
>> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-, OBFF Not Supported ARIFwd-
>> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled ARIFwd-
>> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
>> Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
>> Compliance De-emphasis: -6dB
>> LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
>> EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
>> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
>> Capabilities: [10c v1] Virtual Channel
>> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
>> Arb: Fixed- WRR32- WRR64- WRR128-
>> Ctrl: ArbSelect=Fixed
>> Status: InProgress-
>> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
>> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
>> Status: NegoPending- InProgress-
>> Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1 Len=018 <?>
>>
>> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network Adapter (rev 01)
>> Subsystem: Qualcomm Atheros Device 3112
>> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
>> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>> Latency: 0, Cache Line Size: 128 bytes
>> Interrupt: pin A routed to IRQ 224
>> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
>> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
>> Capabilities: [40] Power Management version 3
>> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA PME(D0+,D1+,D2-,D3hot+,D3cold-)
>> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
>> Address: 0000000000000000 Data: 0000
>> Masking: 00000000 Pending: 00000000
>> Capabilities: [70] Express (v2) Endpoint, MSI 00
>> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <1us, L1 <8us
>> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W
>> DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
>> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
>> MaxPayload 128 bytes, MaxReadReq 512 bytes
>> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
>> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <2us, L1 <64us
>> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
>> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
>> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
>> DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR-, OBFF Not Supported
>> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
>> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-
>> Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
>> Compliance De-emphasis: -6dB
>> LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
>> EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
>> Capabilities: [100 v1] Advanced Error Reporting
>> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
>> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
>> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
>> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
>> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
>> AERCap: First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
>> Capabilities: [140 v1] Virtual Channel
>> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
>> Arb: Fixed- WRR32- WRR64- WRR128-
>> Ctrl: ArbSelect=Fixed
>> Status: InProgress-
>> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
>> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
>> Status: NegoPending- InProgress-
>> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
>> Kernel driver in use: ath9k
>>
>> Here is the cat /proc/interrupts (after we do interface up):
>>
>> root@:~# ifconfig wlan0 up
>> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
>> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
>> CPU0 CPU1 CPU2 CPU3
>> 1: 0 0 0 0 GICv2 29 Edge arch_timer
>> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
>> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
>> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
>> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
>> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
>> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
>> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
>> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
>> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
>> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU, Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
>> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
>> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
>> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
>> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
>> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
>> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
>> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
>> 217: 0 0 0 0 GICv2 165 Level ahci-ceva[fd0c0000.ahci]
>> 218: 61 0 0 0 GICv2 81 Level mmc0
>> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
>> 220: 471 0 0 0 GICv2 53 Level xuartps
>> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
>> 224: 3 0 0 0 dummy 1 Edge ath9k
>> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
>>
>> Regards,
>> Bharat

2016-12-09 14:36:07

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

Correcting Manohar Mail ID.

> Hello there,
>
> as this is a thread about ath9k and ARM64, i'm not sure if i should
> answer here or not, but i have similar "stalls" with ath9k on x86_64
> (starting with 4.9rc), stack trace is posted down below where the
> original ARM64 stall traces are.
>
> Greetings,
>
> Tobias
>
>
> On 08.12.2016 18:36, Kalle Valo wrote:
> > Bharat Kumar Gogada <[email protected]> writes:
> >
> >> > [+cc Kalle, ath9k list]
> > Thanks, but please also CC linux-wireless. Full thread below for the
> > folks there.
> >
> >>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> >>>> Hi,
> >>>>
> >>>> Did anyone test Atheros ATH9 driver(drivers/net/wireless/ath/ath9k/)
> >>>> on ARM64. The end point is TP link wifi card with which supports
> >>>> only legacy interrupts.
> >>> If it works on other arches and the arm64 PCI enumeration works, my
> >>> first guess would be an INTx issue, e.g., maybe the driver is waiting
> >>> for an interrupt that never arrives.
> >> We are not sure for now.
> >>>> We are trying to test it on ARM64 with
> >>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> >>>>
> >>>> EP is getting enumerated and able to link up.
> >>>>
> >>>> But when we start scan system gets hanged.
> >>> When you say the system hangs when you start a scan, I assume you mean
> >>> a wifi scan, not the PCI enumeration. A problem with a wifi scan
> >>> might cause a *process* to hang, but it shouldn't hang the entire
> >>> system.
> >>>
> >> Yes wifi scan.
> >>>> When we took trace we see that after we start scan assert message is
> >>>> sent but there is no de assert from end point.
> >>> Are you talking about a trace from a PCIe analyzer? Do you see an
> >>> Assert_INTx PCIe message on the link?
> >>>
> >> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening
> when we do interface link up.
> >> When we have less debug prints in Atheros driver, and do wifi scan we see
> Assert_INTx but never Deassert_INTx,
> >>>> What might cause end point not sending de assert ?
> >>> If the endpoint doesn't send a Deassert_INTx message, I expect that
> >>> would mean the driver didn't service the interrupt and remove the
> >>> condition that caused the device to assert the interrupt in the first
> >>> place.
> >>>
> >>> If the driver didn't receive the interrupt, it couldn't service it, of
> >>> course. You could add a printk in the ath9k interrupt service
> >>> routine to see if you ever get there.
> >>>
> >> The interrupt behavior is changing w.r.t amount of debug prints we add. (I
> kept many prints to aid debug)
> >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> >> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.074257] ath9k_hw_kill_interrupts 793
> >> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.087882] ath9k_hw_kill_interrupts 793
> >> [ 83.095450] ath9k_hw_enable_interrupts 821
> >> [ 83.099557] ath9k_hw_enable_interrupts 825
> >> [ 83.103721] ath9k_hw_enable_interrupts 832
> >> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.112748] AR_SREV_9100 0
> >> [ 83.115438] ath9k_hw_enable_interrupts 848
> >> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.124389] ath9k_hw_intrpend 762
> >> [ 83.127761] (AR_SREV_9340(ah) val 0
> >> [ 83.131234] ath9k_hw_intrpend 767
> >> [ 83.134628] ath_isr 603
> >> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.146771] ath9k_hw_kill_interrupts 793
> >> [ 83.150864] ath9k_hw_enable_interrupts 821
> >> [ 83.154971] ath9k_hw_enable_interrupts 825
> >> [ 83.159135] ath9k_hw_enable_interrupts 832
> >> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.168161] AR_SREV_9100 0
> >> [ 83.170852] ath9k_hw_enable_interrupts 848
> >> [ 83.170855] ath9k_hw_intrpend 762
> >> [ 83.178398] (AR_SREV_9340(ah) val 0
> >> [ 83.181873] ath9k_hw_intrpend 767
> >> [ 83.185265] ath_isr 603
> >> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.197411] ath9k_hw_kill_interrupts 793
> >> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.206258] ath9k_hw_enable_interrupts 821
> >> [ 83.210368] ath9k_hw_enable_interrupts 825
> >> [ 83.214531] ath9k_hw_enable_interrupts 832
> >> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.223558] AR_SREV_9100 0
> >> [ 83.226243] ath9k_hw_enable_interrupts 848
> >> [ 83.226246] ath9k_hw_intrpend 762
> >> [ 83.233794] (AR_SREV_9340(ah) val 0
> >> [ 83.237268] ath9k_hw_intrpend 767
> >> [ 83.240661] ath_isr 603
> >> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.252806] ath9k_hw_kill_interrupts 793
> >> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.261651] ath9k_hw_enable_interrupts 821
> >> [ 83.265753] ath9k_hw_enable_interrupts 825
> >> [ 83.269919] ath9k_hw_enable_interrupts 832
> >> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.278945] AR_SREV_9100 0
> >> [ 83.281630] ath9k_hw_enable_interrupts 848
> >> [ 83.281633] ath9k_hw_intrpend 762
> >> [ 83.281634] (AR_SREV_9340(ah) val 0
> >> [ 83.281637] ath9k_hw_intrpend 767
> >> [ 83.281648] ath_isr 603
> >> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.281654] ath9k_hw_kill_interrupts 793
> >> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.317030] ath9k_hw_enable_interrupts 821
> >> [ 83.321132] ath9k_hw_enable_interrupts 825
> >> [ 83.325297] ath9k_hw_enable_interrupts 832
> >> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.334324] AR_SREV_9100 0
> >> [ 83.337014] ath9k_hw_enable_interrupts 848
> >> ..
> >> ..
> >> This log continues until I turn off board without obtaining scanning result.
> >>
> >> In between I get following cpu stall outputs :
> >> 230.457179] INFO: rcu_sched self-detected stall on CPU
> >> [ 230.457185] 2-...: (31314 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> >> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> >> [ 230.457191] Task dump for CPU 2:
> >> [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> >> [ 230.457207] Workqueue: phy0 ieee80211_scan_work
> >> [ 230.457208] Call trace:
> >> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198
> >> [ 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20
> >> [ 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8
> >> [ 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50
> >> [ 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0
> >> [ 230.457239] [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748
> >> [ 230.457243] [<ffffff80080e7cfc>] update_process_times+0x3c/0x68
> >> [ 230.457249] [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> >> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90
> >> [ 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> >> ** 10 printk messages dropped ** [ 230.457302] f8c0: 0000000000000000
> 0000000005f5e0ff 000000000001379a 3866666666666620
> >> [ 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000
> ffffffc87b8010a8
> >> [ 230.457310] f900: ffffff808a1b4057 ffffff800a1c3000 ffffff800a1b3000
> ffffff800a13b000
> >> [ 230.457314] f920: 0000000000000140 0000000000000006
> ffffff800a1b3b10 ffffff800a1c39e8
> >> [ 230.457318] f940: 000000000000002f ffffff800a1b8a98 ffffff800a1b3ae8
> ffffffc87b07f990
> >> [ 230.457322] f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> 0000000060000145
> >> ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>]
> el1_irq+0xa0/0x100
> >> ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>]
> ieee80211_hw_config+0x50/0x290
> >> [ 230.457377] [<ffffff8008863690>] ieee80211_scan_work+0x1f8/0x480
> >> [ 230.457383] [<ffffff80080b15d0>] process_one_work+0x120/0x378
> >> [ 230.457386] [<ffffff80080b1870>] worker_thread+0x48/0x4b0
> >> [ 230.457391] [<ffffff80080b7108>] kthread+0xd0/0xe8
> >> [ 230.457395] [<ffffff8008085dd0>] ret_from_fork+0x10/0x40
> >> [ 230.480389] ath9k_hw_intrpend 762
> >>
> >>
> >> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 545.526189] INFO: rcu_sched self-detected stall on CPU
> >> [ 545.526195] 2-...: (97636 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> >> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> >> [ 545.526201] Task dump for CPU 2:
> >> [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> >> ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>]
> show_stack+0x14/0x20
> >> ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>]
> arch_timer_handler_phys+0x30/0x40
> >> [ 545.526284] [<ffffff80080dbe18>] handle_percpu_devid_irq+0x78/0xa0
> >> [ 545.526291] [<ffffff80080d760c>] generic_handle_irq+0x24/0x38
> >> [ 545.526296] [<ffffff80080d7944>] __handle_domain_irq+0x5c/0xb8
> >> [ 545.526299] [<ffffff80080824bc>] gic_handle_irq+0x64/0xc0
> >> [ 545.526302] Exception stack(0xffffffc87b07f870 to 0xffffffc87b07f990)
> >> [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> >> ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8
> 0000000000000036
> >> [ 545.526345] [<ffffff8008085720>] el1_irq+0xa0/0x100
> >> [ 545.526349] [<ffffff80080d6234>] console_unlock+0x384/0x5b0
> >> [ 545.526353] [<ffffff80080d673c>] vprintk_emit+0x2dc/0x4b0
> >> [ 545.526357] [<ffffff80080d6a50>] vprintk_default+0x38/0x40
> >> [ 545.526362] [<ffffff8008129704>] printk+0x58/0x60
> >> [ 545.526366] [<ffffff800859e3e4>] ath9k_iowrite32+0x9c/0xa8
> >> [ 545.526372] [<ffffff80085c7ca8>] ath9k_hw_kill_interrupts+0x28/0xf0
> >> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> >> ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>]
> ieee80211_hw_config+0x50/0x290
> >> ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts
> 793
> >> [ 545.532890] ath9k_hw_enable_interrupts 821
>
> [ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
> [ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
> [ 81.876936] swapper/4 R running task 0 0 1
> 0x00000000
> [ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> ffffffff81a3dc40
> [ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> ffffffff81a3dc40
> [ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
> ffff88017edbc240
> [ 81.876951] Call Trace:
> [ 81.876970] <IRQ>
> [ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> [ 81.876983] [<ffffffff81101e46>] ?
> rcu_print_detail_task_stall_rnp+0x40/0x61
> [ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
> [ 81.876993] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> [ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> [ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> [ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> [ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> [ 81.877008] [<ffffffff81031b1e>] ?
> smp_trace_apic_timer_interrupt+0x5e/0x90
> [ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> [ 81.877013] <EOI>
> [ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> [ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> [ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> [ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> [ 81.877029] swapper/4 R running task 0 0 1
> 0x00000000
> [ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> ffffffff81a3dc40
> [ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> ffffffff81a3dc40
> [ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
> ffff88017edbc240
> [ 81.877041] Call Trace:
> [ 81.877045] <IRQ>
> [ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> [ 81.877051] [<ffffffff81101e46>] ?
> rcu_print_detail_task_stall_rnp+0x40/0x61
> [ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
> [ 81.877058] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> [ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> [ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> [ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> [ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> [ 81.877070] [<ffffffff81031b1e>] ?
> smp_trace_apic_timer_interrupt+0x5e/0x90
> [ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> [ 81.877074] <EOI>
> [ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> [ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> [ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> [ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> [ 91.132787] INFO: rcu_preempt detected expedited stalls on
> CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
> [ 91.132796] blocking rcu_node structures:
>
> >>
> >>
> >> But if we have less debug prints it does not reach EP handler sometimes, due
> to following
> >> Condition in "kernel/irq/chip.c" in function handle_simple_irq
> >>
> >> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> >> desc->istate |= IRQS_PENDING;
> >> goto out_unlock;
> >> }
> >> Here irqd_irq_disabled is being set to 1.
> >>
> >> With lesser debug prints it stops after following prints:
> >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> >> [ 54.781045] ath9k_hw_kill_interrupts 793
> >> [ 54.785007] ath9k_hw_kill_interrupts 793
> >> [ 54.792535] ath9k_hw_enable_interrupts 821
> >> [ 54.796642] ath9k_hw_enable_interrupts 825
> >> [ 54.800807] ath9k_hw_enable_interrupts 832
> >> [ 54.804973] AR_SREV_9100 0
> >> [ 54.807663] ath9k_hw_enable_interrupts 848
> >> [ 54.811843] ath9k_hw_intrpend 762
> >> [ 54.815211] (AR_SREV_9340(ah) val 0
> >> [ 54.818684] ath9k_hw_intrpend 767
> >> [ 54.822078] ath_isr 603
> >> [ 54.824587] ath9k_hw_kill_interrupts 793
> >> [ 54.828601] ath9k_hw_enable_interrupts 821
> >> [ 54.832750] ath9k_hw_enable_interrupts 825
> >> [ 54.836916] ath9k_hw_enable_interrupts 832
> >> [ 54.841082] AR_SREV_9100 0
> >> [ 54.843772] ath9k_hw_enable_interrupts 848
> >> [ 54.843775] ath9k_hw_intrpend 762
> >> [ 54.851319] (AR_SREV_9340(ah) val 0
> >> [ 54.854793] ath9k_hw_intrpend 767
> >> [ 54.858185] ath_isr 603
> >> [ 54.860696] ath9k_hw_kill_interrupts 793
> >> [ 54.864776] ath9k_hw_enable_interrupts 821
> >> [ 54.867061] ath9k_hw_kill_interrupts 793
> >> [ 54.872870] ath9k_hw_enable_interrupts 825
> >> [ 54.877036] ath9k_hw_enable_interrupts 832
> >> [ 54.881202] AR_SREV_9100 0
> >> [ 54.883892] ath9k_hw_enable_interrupts 848
> >> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> >> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=519
> >> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> >> [ 75.982485] Task dump for CPU 0:
> >> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> >> [ 75.992726] Call trace:
> >> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> >> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> >> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> >> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=2097
> >> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> >> [ 139.078489] Task dump for CPU 0:
> >> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> >> [ 139.088731] Call trace:
> >> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> >> [ 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> >>
> >>
> >>>> We are not seeing any issues on 32-bit ARM platform and X86
> >>>> platform.
> >>> Can you collect a dmesg log (or, if the system hang means you can't
> >>> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> >>> output as root? That should have clues about whether the INTx got
> >>> routed correctly. /proc/interrupts should also show whether we're
> >>> receiving interrupts from the device.
> >> Here is the lspci output:
> >> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal
> decode])
> >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> >> Latency: 0
> >> Interrupt: pin A routed to IRQ 224
> >> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> >> I/O behind bridge: 00000000-00000fff
> >> Memory behind bridge: e0000000-e00fffff
> >> Prefetchable memory behind bridge: 00000000fff00000-
> 00000000000fffff
> >> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- <SERR- <PERR-
> >> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> >> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> >> Capabilities: [40] Power Management version 3
> >> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> PME(D0+,D1+,D2+,D3hot+,D3cold-)
> >> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> >> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> >> DevCap: MaxPayload 256 bytes, PhantFunc 0
> >> ExtTag- RBE+
> >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend+
> >> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> Exit Latency L0s unlimited, L1 unlimited
> >> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> >> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> CRSVisible+
> >> RootCap: CRSVisible+
> >> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> >> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> OBFF Not Supported ARIFwd-
> >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled ARIFwd-
> >> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> >> Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> >> Compliance De-emphasis: -6dB
> >> LnkSta2: Current De-emphasis Level: -3.5dB,
> EqualizationComplete-, EqualizationPhase1-
> >> EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> >> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> >> Capabilities: [10c v1] Virtual Channel
> >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> >> Arb: Fixed- WRR32- WRR64- WRR128-
> >> Ctrl: ArbSelect=Fixed
> >> Status: InProgress-
> >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> >> Status: NegoPending- InProgress-
> >> Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1
> Len=018 <?>
> >>
> >> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network
> Adapter (rev 01)
> >> Subsystem: Qualcomm Atheros Device 3112
> >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> >> Latency: 0, Cache Line Size: 128 bytes
> >> Interrupt: pin A routed to IRQ 224
> >> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> >> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> >> Capabilities: [40] Power Management version 3
> >> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> PME(D0+,D1+,D2-,D3hot+,D3cold-)
> >> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> >> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> >> Address: 0000000000000000 Data: 0000
> >> Masking: 00000000 Pending: 00000000
> >> Capabilities: [70] Express (v2) Endpoint, MSI 00
> >> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> L0s <1us, L1 <8us
> >> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> SlotPowerLimit 0.000W
> >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend-
> >> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> Latency L0s <2us, L1 <64us
> >> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> >> DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> LTR-, OBFF Not Supported
> >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled
> >> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> SpeedDis-
> >> Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> >> Compliance De-emphasis: -6dB
> >> LnkSta2: Current De-emphasis Level: -6dB,
> EqualizationComplete-, EqualizationPhase1-
> >> EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> >> Capabilities: [100 v1] Advanced Error Reporting
> >> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> >> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> >> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> >> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr-
> >> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr+
> >> AERCap: First Error Pointer: 00, GenCap- CGenEn-
> ChkCap- ChkEn-
> >> Capabilities: [140 v1] Virtual Channel
> >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> >> Arb: Fixed- WRR32- WRR64- WRR128-
> >> Ctrl: ArbSelect=Fixed
> >> Status: InProgress-
> >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> >> Status: NegoPending- InProgress-
> >> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> >> Kernel driver in use: ath9k
> >>
> >> Here is the cat /proc/interrupts (after we do interface up):
> >>
> >> root@:~# ifconfig wlan0 up
> >> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> >> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> >> CPU0 CPU1 CPU2 CPU3
> >> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> >> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> >> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> >> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> >> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> >> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> >> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> >> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> >> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> >> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> >> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> >> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> >> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> >> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> >> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> >> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> >> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> >> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> >> 217: 0 0 0 0 GICv2 165 Level ahci-
> ceva[fd0c0000.ahci]
> >> 218: 61 0 0 0 GICv2 81 Level mmc0
> >> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> >> 220: 471 0 0 0 GICv2 53 Level xuartps
> >> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> >> 224: 3 0 0 0 dummy 1 Edge ath9k
> >> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> >>
> >> Regards,
> >> Bharat


2016-12-10 14:41:04

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

Hi,

After taking some more lecroy traces, we see that after 2nd ASSERT from EP on ARM64 we see continuous data movement of 32 dwords or 12 dwords and never sign of DEASSERT.
Comparatively on working traces (x86) after 2nd assert there are only BAR register reads and writes and then DEASSERT, for almost most of the interrupts and we haven't seen 12 or 32 dwords data movement on this trace.

I did not work on EP wifi/network drivers, any help why EP needs those many number of data at scan time ?

Regards,
Bharat


> Hello there,
>
> as this is a thread about ath9k and ARM64, i'm not sure if i should answer here
> or not, but i have similar "stalls" with ath9k on x86_64 (starting with 4.9rc), stack
> trace is posted down below where the original ARM64 stall traces are.
>
> Greetings,
>
> Tobias
>
>
> On 08.12.2016 18:36, Kalle Valo wrote:
> > Bharat Kumar Gogada <[email protected]> writes:
> >
> >> > [+cc Kalle, ath9k list]
> > Thanks, but please also CC linux-wireless. Full thread below for the
> > folks there.
> >
> >>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> >>>> Hi,
> >>>>
> >>>> Did anyone test Atheros ATH9
> >>>> driver(drivers/net/wireless/ath/ath9k/)
> >>>> on ARM64. The end point is TP link wifi card with which supports
> >>>> only legacy interrupts.
> >>> If it works on other arches and the arm64 PCI enumeration works, my
> >>> first guess would be an INTx issue, e.g., maybe the driver is
> >>> waiting for an interrupt that never arrives.
> >> We are not sure for now.
> >>>> We are trying to test it on ARM64 with
> >>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> >>>>
> >>>> EP is getting enumerated and able to link up.
> >>>>
> >>>> But when we start scan system gets hanged.
> >>> When you say the system hangs when you start a scan, I assume you
> >>> mean a wifi scan, not the PCI enumeration. A problem with a wifi
> >>> scan might cause a *process* to hang, but it shouldn't hang the
> >>> entire system.
> >>>
> >> Yes wifi scan.
> >>>> When we took trace we see that after we start scan assert message
> >>>> is sent but there is no de assert from end point.
> >>> Are you talking about a trace from a PCIe analyzer? Do you see an
> >>> Assert_INTx PCIe message on the link?
> >>>
> >> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening
> when we do interface link up.
> >> When we have less debug prints in Atheros driver, and do wifi scan we
> >> see Assert_INTx but never Deassert_INTx,
> >>>> What might cause end point not sending de assert ?
> >>> If the endpoint doesn't send a Deassert_INTx message, I expect that
> >>> would mean the driver didn't service the interrupt and remove the
> >>> condition that caused the device to assert the interrupt in the
> >>> first place.
> >>>
> >>> If the driver didn't receive the interrupt, it couldn't service it,
> >>> of course. You could add a printk in the ath9k interrupt service
> >>> routine to see if you ever get there.
> >>>
> >> The interrupt behavior is changing w.r.t amount of debug prints we
> >> add. (I kept many prints to aid debug) root@Xilinx-ZCU102-2016_3:~# iw dev
> wlan0 scan
> >> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.074257] ath9k_hw_kill_interrupts 793
> >> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.087882] ath9k_hw_kill_interrupts 793
> >> [ 83.095450] ath9k_hw_enable_interrupts 821
> >> [ 83.099557] ath9k_hw_enable_interrupts 825
> >> [ 83.103721] ath9k_hw_enable_interrupts 832
> >> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.112748] AR_SREV_9100 0
> >> [ 83.115438] ath9k_hw_enable_interrupts 848
> >> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.124389] ath9k_hw_intrpend 762
> >> [ 83.127761] (AR_SREV_9340(ah) val 0
> >> [ 83.131234] ath9k_hw_intrpend 767
> >> [ 83.134628] ath_isr 603
> >> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.146771] ath9k_hw_kill_interrupts 793
> >> [ 83.150864] ath9k_hw_enable_interrupts 821
> >> [ 83.154971] ath9k_hw_enable_interrupts 825
> >> [ 83.159135] ath9k_hw_enable_interrupts 832
> >> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.168161] AR_SREV_9100 0
> >> [ 83.170852] ath9k_hw_enable_interrupts 848
> >> [ 83.170855] ath9k_hw_intrpend 762
> >> [ 83.178398] (AR_SREV_9340(ah) val 0
> >> [ 83.181873] ath9k_hw_intrpend 767
> >> [ 83.185265] ath_isr 603
> >> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.197411] ath9k_hw_kill_interrupts 793
> >> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.206258] ath9k_hw_enable_interrupts 821
> >> [ 83.210368] ath9k_hw_enable_interrupts 825
> >> [ 83.214531] ath9k_hw_enable_interrupts 832
> >> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.223558] AR_SREV_9100 0
> >> [ 83.226243] ath9k_hw_enable_interrupts 848
> >> [ 83.226246] ath9k_hw_intrpend 762
> >> [ 83.233794] (AR_SREV_9340(ah) val 0
> >> [ 83.237268] ath9k_hw_intrpend 767
> >> [ 83.240661] ath_isr 603
> >> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.252806] ath9k_hw_kill_interrupts 793
> >> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.261651] ath9k_hw_enable_interrupts 821
> >> [ 83.265753] ath9k_hw_enable_interrupts 825
> >> [ 83.269919] ath9k_hw_enable_interrupts 832
> >> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.278945] AR_SREV_9100 0
> >> [ 83.281630] ath9k_hw_enable_interrupts 848
> >> [ 83.281633] ath9k_hw_intrpend 762
> >> [ 83.281634] (AR_SREV_9340(ah) val 0
> >> [ 83.281637] ath9k_hw_intrpend 767
> >> [ 83.281648] ath_isr 603
> >> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.281654] ath9k_hw_kill_interrupts 793
> >> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> >> [ 83.317030] ath9k_hw_enable_interrupts 821
> >> [ 83.321132] ath9k_hw_enable_interrupts 825
> >> [ 83.325297] ath9k_hw_enable_interrupts 832
> >> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> >> [ 83.334324] AR_SREV_9100 0
> >> [ 83.337014] ath9k_hw_enable_interrupts 848
> >> ..
> >> ..
> >> This log continues until I turn off board without obtaining scanning result.
> >>
> >> In between I get following cpu stall outputs :
> >> 230.457179] INFO: rcu_sched self-detected stall on CPU
> >> [ 230.457185] 2-...: (31314 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> >> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> >> [ 230.457191] Task dump for CPU 2:
> >> [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> >> [ 230.457207] Workqueue: phy0 ieee80211_scan_work [ 230.457208]
> >> Call trace:
> >> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> >> 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [ 230.457224]
> >> [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [ 230.457228]
> >> [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [ 230.457233]
> >> [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0 [ 230.457239]
> >> [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748 [ 230.457243]
> >> [<ffffff80080e7cfc>] update_process_times+0x3c/0x68 [ 230.457249]
> >> [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> >> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90 [
> >> 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> >> ** 10 printk messages dropped ** [ 230.457302] f8c0:
> >> 0000000000000000 0000000005f5e0ff 000000000001379a
> 3866666666666620 [
> >> 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000
> >> ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> >> ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [ 230.457314]
> >> f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> >> ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> >> ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [ 230.457322]
> >> f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> >> 0000000060000145
> >> ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>]
> >> el1_irq+0xa0/0x100
> >> ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>]
> >> ieee80211_hw_config+0x50/0x290 [ 230.457377] [<ffffff8008863690>]
> >> ieee80211_scan_work+0x1f8/0x480 [ 230.457383] [<ffffff80080b15d0>]
> >> process_one_work+0x120/0x378 [ 230.457386] [<ffffff80080b1870>]
> >> worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> >> kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> ret_from_fork+0x10/0x40
> >> [ 230.480389] ath9k_hw_intrpend 762
> >>
> >>
> >> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [ 545.526189]
> >> INFO: rcu_sched self-detected stall on CPU
> >> [ 545.526195] 2-...: (97636 ticks this GP)
> idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> >> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> >> [ 545.526201] Task dump for CPU 2:
> >> [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> >> ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>]
> >> show_stack+0x14/0x20
> >> ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>]
> >> arch_timer_handler_phys+0x30/0x40 [ 545.526284] [<ffffff80080dbe18>]
> >> handle_percpu_devid_irq+0x78/0xa0 [ 545.526291] [<ffffff80080d760c>]
> >> generic_handle_irq+0x24/0x38 [ 545.526296] [<ffffff80080d7944>]
> >> __handle_domain_irq+0x5c/0xb8 [ 545.526299] [<ffffff80080824bc>]
> >> gic_handle_irq+0x64/0xc0 [ 545.526302] Exception stack(0xffffffc87b07f870
> to 0xffffffc87b07f990)
> >> [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> >> ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8
> >> 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> >> el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> >> console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> >> vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> >> vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> >> printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> >> ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> >> ath9k_hw_kill_interrupts+0x28/0xf0
> >> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> >> ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>]
> ieee80211_hw_config+0x50/0x290
> >> ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts
> 793
> >> [ 545.532890] ath9k_hw_enable_interrupts 821
>
> [ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
> [ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
> [ 81.876936] swapper/4 R running task 0 0 1
> 0x00000000
> [ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> ffffffff81a3dc40
> [ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> ffffffff81a3dc40
> [ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
> ffff88017edbc240
> [ 81.876951] Call Trace:
> [ 81.876970] <IRQ>
> [ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> [ 81.876983] [<ffffffff81101e46>] ?
> rcu_print_detail_task_stall_rnp+0x40/0x61
> [ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
> [ 81.876993] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> [ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> [ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> [ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> [ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> [ 81.877008] [<ffffffff81031b1e>] ?
> smp_trace_apic_timer_interrupt+0x5e/0x90
> [ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> [ 81.877013] <EOI>
> [ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> [ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> [ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> [ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> [ 81.877029] swapper/4 R running task 0 0 1
> 0x00000000
> [ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> ffffffff81a3dc40
> [ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> ffffffff81a3dc40
> [ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
> ffff88017edbc240
> [ 81.877041] Call Trace:
> [ 81.877045] <IRQ>
> [ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> [ 81.877051] [<ffffffff81101e46>] ?
> rcu_print_detail_task_stall_rnp+0x40/0x61
> [ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
> [ 81.877058] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> [ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> [ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> [ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> [ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> [ 81.877070] [<ffffffff81031b1e>] ?
> smp_trace_apic_timer_interrupt+0x5e/0x90
> [ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> [ 81.877074] <EOI>
> [ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> [ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> [ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> [ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> [ 91.132787] INFO: rcu_preempt detected expedited stalls on
> CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
> [ 91.132796] blocking rcu_node structures:
>
> >>
> >>
> >> But if we have less debug prints it does not reach EP handler
> >> sometimes, due to following Condition in "kernel/irq/chip.c" in
> >> function handle_simple_irq
> >>
> >> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> >> desc->istate |= IRQS_PENDING;
> >> goto out_unlock;
> >> }
> >> Here irqd_irq_disabled is being set to 1.
> >>
> >> With lesser debug prints it stops after following prints:
> >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> >> [ 54.781045] ath9k_hw_kill_interrupts 793
> >> [ 54.785007] ath9k_hw_kill_interrupts 793
> >> [ 54.792535] ath9k_hw_enable_interrupts 821
> >> [ 54.796642] ath9k_hw_enable_interrupts 825
> >> [ 54.800807] ath9k_hw_enable_interrupts 832
> >> [ 54.804973] AR_SREV_9100 0
> >> [ 54.807663] ath9k_hw_enable_interrupts 848
> >> [ 54.811843] ath9k_hw_intrpend 762
> >> [ 54.815211] (AR_SREV_9340(ah) val 0
> >> [ 54.818684] ath9k_hw_intrpend 767
> >> [ 54.822078] ath_isr 603
> >> [ 54.824587] ath9k_hw_kill_interrupts 793
> >> [ 54.828601] ath9k_hw_enable_interrupts 821
> >> [ 54.832750] ath9k_hw_enable_interrupts 825
> >> [ 54.836916] ath9k_hw_enable_interrupts 832
> >> [ 54.841082] AR_SREV_9100 0
> >> [ 54.843772] ath9k_hw_enable_interrupts 848
> >> [ 54.843775] ath9k_hw_intrpend 762
> >> [ 54.851319] (AR_SREV_9340(ah) val 0
> >> [ 54.854793] ath9k_hw_intrpend 767
> >> [ 54.858185] ath_isr 603
> >> [ 54.860696] ath9k_hw_kill_interrupts 793
> >> [ 54.864776] ath9k_hw_enable_interrupts 821
> >> [ 54.867061] ath9k_hw_kill_interrupts 793
> >> [ 54.872870] ath9k_hw_enable_interrupts 825
> >> [ 54.877036] ath9k_hw_enable_interrupts 832
> >> [ 54.881202] AR_SREV_9100 0
> >> [ 54.883892] ath9k_hw_enable_interrupts 848
> >> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> >> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=519
> >> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> >> [ 75.982485] Task dump for CPU 0:
> >> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> >> [ 75.992726] Call trace:
> >> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> >> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> >> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> >> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> softirq=1103/1109 fqs=2097
> >> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> >> [ 139.078489] Task dump for CPU 0:
> >> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> >> [ 139.088731] Call trace:
> >> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> >> 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> >>
> >>
> >>>> We are not seeing any issues on 32-bit ARM platform and X86
> >>>> platform.
> >>> Can you collect a dmesg log (or, if the system hang means you can't
> >>> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> >>> output as root? That should have clues about whether the INTx got
> >>> routed correctly. /proc/interrupts should also show whether we're
> >>> receiving interrupts from the device.
> >> Here is the lspci output:
> >> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal
> decode])
> >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> >> Latency: 0
> >> Interrupt: pin A routed to IRQ 224
> >> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> >> I/O behind bridge: 00000000-00000fff
> >> Memory behind bridge: e0000000-e00fffff
> >> Prefetchable memory behind bridge: 00000000fff00000-
> 00000000000fffff
> >> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- <SERR- <PERR-
> >> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> >> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> >> Capabilities: [40] Power Management version 3
> >> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> PME(D0+,D1+,D2+,D3hot+,D3cold-)
> >> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> >> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> >> DevCap: MaxPayload 256 bytes, PhantFunc 0
> >> ExtTag- RBE+
> >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend+
> >> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> Exit Latency L0s unlimited, L1 unlimited
> >> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> >> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> CRSVisible+
> >> RootCap: CRSVisible+
> >> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> >> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> OBFF Not Supported ARIFwd-
> >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled ARIFwd-
> >> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> >> Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> >> Compliance De-emphasis: -6dB
> >> LnkSta2: Current De-emphasis Level: -3.5dB,
> EqualizationComplete-, EqualizationPhase1-
> >> EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> >> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> >> Capabilities: [10c v1] Virtual Channel
> >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> >> Arb: Fixed- WRR32- WRR64- WRR128-
> >> Ctrl: ArbSelect=Fixed
> >> Status: InProgress-
> >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> >> Status: NegoPending- InProgress-
> >> Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1
> >> Len=018 <?>
> >>
> >> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network
> Adapter (rev 01)
> >> Subsystem: Qualcomm Atheros Device 3112
> >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
> >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
> >> Latency: 0, Cache Line Size: 128 bytes
> >> Interrupt: pin A routed to IRQ 224
> >> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> >> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> >> Capabilities: [40] Power Management version 3
> >> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> PME(D0+,D1+,D2-,D3hot+,D3cold-)
> >> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> >> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> >> Address: 0000000000000000 Data: 0000
> >> Masking: 00000000 Pending: 00000000
> >> Capabilities: [70] Express (v2) Endpoint, MSI 00
> >> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> L0s <1us, L1 <8us
> >> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> SlotPowerLimit 0.000W
> >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
> >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> TransPend-
> >> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> Latency L0s <2us, L1 <64us
> >> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
> >> DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> LTR-, OBFF Not Supported
> >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> OBFF Disabled
> >> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> SpeedDis-
> >> Transmit Margin: Normal Operating Range,
> EnterModifiedCompliance- ComplianceSOS-
> >> Compliance De-emphasis: -6dB
> >> LnkSta2: Current De-emphasis Level: -6dB,
> EqualizationComplete-, EqualizationPhase1-
> >> EqualizationPhase2-, EqualizationPhase3-,
> LinkEqualizationRequest-
> >> Capabilities: [100 v1] Advanced Error Reporting
> >> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> >> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> >> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> >> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr-
> >> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> NonFatalErr+
> >> AERCap: First Error Pointer: 00, GenCap- CGenEn-
> ChkCap- ChkEn-
> >> Capabilities: [140 v1] Virtual Channel
> >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> >> Arb: Fixed- WRR32- WRR64- WRR128-
> >> Ctrl: ArbSelect=Fixed
> >> Status: InProgress-
> >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> WRR256-
> >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> >> Status: NegoPending- InProgress-
> >> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> >> Kernel driver in use: ath9k
> >>
> >> Here is the cat /proc/interrupts (after we do interface up):
> >>
> >> root@:~# ifconfig wlan0 up
> >> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> >> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> >> CPU0 CPU1 CPU2 CPU3
> >> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> >> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> >> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> >> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> >> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> >> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> >> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> >> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> >> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> >> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> >> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> >> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> >> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> >> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> >> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> >> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> >> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> >> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> >> 217: 0 0 0 0 GICv2 165 Level ahci-
> ceva[fd0c0000.ahci]
> >> 218: 61 0 0 0 GICv2 81 Level mmc0
> >> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> >> 220: 471 0 0 0 GICv2 53 Level xuartps
> >> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> >> 224: 3 0 0 0 dummy 1 Edge ath9k
> >> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> >>
> >> Regards,
> >> Bharat


2016-12-12 16:31:27

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: ATH9 driver issues on ARM64

On Sat, Dec 10, 2016 at 02:40:48PM +0000, Bharat Kumar Gogada wrote:
> Hi,
>
> After taking some more lecroy traces, we see that after 2nd ASSERT from EP on ARM64 we see continuous data movement of 32 dwords or 12 dwords and never sign of DEASSERT.
> Comparatively on working traces (x86) after 2nd assert there are only BAR register reads and writes and then DEASSERT, for almost most of the interrupts and we haven't seen 12 or 32 dwords data movement on this trace.
>
> I did not work on EP wifi/network drivers, any help why EP needs those many number of data at scan time ?

The device doesn't know whether it's in an x86 or an arm64 system. If
it works differently, it must be because the PCI core or the driver is
programming the device differently.

You should be able to match up Memory transactions from the host in
the trace with things the driver does. For example, if you see an
Assert_INTx message from the device, you should eventually see a
Memory Read from the host to get the ISR, i.e., some read done in the
bowels of ath9k_hw_getisr().

I don't know how the ath9k device works, but there must be some Memory
Read or Write done by the driver that tells the device "we've handled
this interrupt". The device should then send a Deassert_INTx; of
course, if the device still requires service, e.g., because it has
received more packets, it might leave the INTx asserted.

I doubt you'd see exactly the same traces on x86 and arm64 because
they aren't seeing the same network packets and the driver is
executing at different rates. But you should at least be able to
identify interrupt assertion and the actions of the driver's interrupt
service routine.

> > Hello there,
> >
> > as this is a thread about ath9k and ARM64, i'm not sure if i should answer here
> > or not, but i have similar "stalls" with ath9k on x86_64 (starting with 4.9rc), stack
> > trace is posted down below where the original ARM64 stall traces are.
> >
> > Greetings,
> >
> > Tobias
> >
> >
> > On 08.12.2016 18:36, Kalle Valo wrote:
> > > Bharat Kumar Gogada <[email protected]> writes:
> > >
> > >> > [+cc Kalle, ath9k list]
> > > Thanks, but please also CC linux-wireless. Full thread below for the
> > > folks there.
> > >
> > >>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada wrote:
> > >>>> Hi,
> > >>>>
> > >>>> Did anyone test Atheros ATH9
> > >>>> driver(drivers/net/wireless/ath/ath9k/)
> > >>>> on ARM64. The end point is TP link wifi card with which supports
> > >>>> only legacy interrupts.
> > >>> If it works on other arches and the arm64 PCI enumeration works, my
> > >>> first guess would be an INTx issue, e.g., maybe the driver is
> > >>> waiting for an interrupt that never arrives.
> > >> We are not sure for now.
> > >>>> We are trying to test it on ARM64 with
> > >>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> > >>>>
> > >>>> EP is getting enumerated and able to link up.
> > >>>>
> > >>>> But when we start scan system gets hanged.
> > >>> When you say the system hangs when you start a scan, I assume you
> > >>> mean a wifi scan, not the PCI enumeration. A problem with a wifi
> > >>> scan might cause a *process* to hang, but it shouldn't hang the
> > >>> entire system.
> > >>>
> > >> Yes wifi scan.
> > >>>> When we took trace we see that after we start scan assert message
> > >>>> is sent but there is no de assert from end point.
> > >>> Are you talking about a trace from a PCIe analyzer? Do you see an
> > >>> Assert_INTx PCIe message on the link?
> > >>>
> > >> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx happening
> > when we do interface link up.
> > >> When we have less debug prints in Atheros driver, and do wifi scan we
> > >> see Assert_INTx but never Deassert_INTx,
> > >>>> What might cause end point not sending de assert ?
> > >>> If the endpoint doesn't send a Deassert_INTx message, I expect that
> > >>> would mean the driver didn't service the interrupt and remove the
> > >>> condition that caused the device to assert the interrupt in the
> > >>> first place.
> > >>>
> > >>> If the driver didn't receive the interrupt, it couldn't service it,
> > >>> of course. You could add a printk in the ath9k interrupt service
> > >>> routine to see if you ever get there.
> > >>>
> > >> The interrupt behavior is changing w.r.t amount of debug prints we
> > >> add. (I kept many prints to aid debug) root@Xilinx-ZCU102-2016_3:~# iw dev
> > wlan0 scan
> > >> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.074257] ath9k_hw_kill_interrupts 793
> > >> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.087882] ath9k_hw_kill_interrupts 793
> > >> [ 83.095450] ath9k_hw_enable_interrupts 821
> > >> [ 83.099557] ath9k_hw_enable_interrupts 825
> > >> [ 83.103721] ath9k_hw_enable_interrupts 832
> > >> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.112748] AR_SREV_9100 0
> > >> [ 83.115438] ath9k_hw_enable_interrupts 848
> > >> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.124389] ath9k_hw_intrpend 762
> > >> [ 83.127761] (AR_SREV_9340(ah) val 0
> > >> [ 83.131234] ath9k_hw_intrpend 767
> > >> [ 83.134628] ath_isr 603
> > >> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.146771] ath9k_hw_kill_interrupts 793
> > >> [ 83.150864] ath9k_hw_enable_interrupts 821
> > >> [ 83.154971] ath9k_hw_enable_interrupts 825
> > >> [ 83.159135] ath9k_hw_enable_interrupts 832
> > >> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.168161] AR_SREV_9100 0
> > >> [ 83.170852] ath9k_hw_enable_interrupts 848
> > >> [ 83.170855] ath9k_hw_intrpend 762
> > >> [ 83.178398] (AR_SREV_9340(ah) val 0
> > >> [ 83.181873] ath9k_hw_intrpend 767
> > >> [ 83.185265] ath_isr 603
> > >> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.197411] ath9k_hw_kill_interrupts 793
> > >> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.206258] ath9k_hw_enable_interrupts 821
> > >> [ 83.210368] ath9k_hw_enable_interrupts 825
> > >> [ 83.214531] ath9k_hw_enable_interrupts 832
> > >> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.223558] AR_SREV_9100 0
> > >> [ 83.226243] ath9k_hw_enable_interrupts 848
> > >> [ 83.226246] ath9k_hw_intrpend 762
> > >> [ 83.233794] (AR_SREV_9340(ah) val 0
> > >> [ 83.237268] ath9k_hw_intrpend 767
> > >> [ 83.240661] ath_isr 603
> > >> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.252806] ath9k_hw_kill_interrupts 793
> > >> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.261651] ath9k_hw_enable_interrupts 821
> > >> [ 83.265753] ath9k_hw_enable_interrupts 825
> > >> [ 83.269919] ath9k_hw_enable_interrupts 832
> > >> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.278945] AR_SREV_9100 0
> > >> [ 83.281630] ath9k_hw_enable_interrupts 848
> > >> [ 83.281633] ath9k_hw_intrpend 762
> > >> [ 83.281634] (AR_SREV_9340(ah) val 0
> > >> [ 83.281637] ath9k_hw_intrpend 767
> > >> [ 83.281648] ath_isr 603
> > >> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.281654] ath9k_hw_kill_interrupts 793
> > >> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> > >> [ 83.317030] ath9k_hw_enable_interrupts 821
> > >> [ 83.321132] ath9k_hw_enable_interrupts 825
> > >> [ 83.325297] ath9k_hw_enable_interrupts 832
> > >> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> > >> [ 83.334324] AR_SREV_9100 0
> > >> [ 83.337014] ath9k_hw_enable_interrupts 848
> > >> ..
> > >> ..
> > >> This log continues until I turn off board without obtaining scanning result.
> > >>
> > >> In between I get following cpu stall outputs :
> > >> 230.457179] INFO: rcu_sched self-detected stall on CPU
> > >> [ 230.457185] 2-...: (31314 ticks this GP)
> > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> > >> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> > >> [ 230.457191] Task dump for CPU 2:
> > >> [ 230.457196] kworker/u8:4 R running task 0 1342 2 0x00000002
> > >> [ 230.457207] Workqueue: phy0 ieee80211_scan_work [ 230.457208]
> > >> Call trace:
> > >> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> > >> 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [ 230.457224]
> > >> [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [ 230.457228]
> > >> [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [ 230.457233]
> > >> [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0 [ 230.457239]
> > >> [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748 [ 230.457243]
> > >> [<ffffff80080e7cfc>] update_process_times+0x3c/0x68 [ 230.457249]
> > >> [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> > >> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90 [
> > >> 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> > >> ** 10 printk messages dropped ** [ 230.457302] f8c0:
> > >> 0000000000000000 0000000005f5e0ff 000000000001379a
> > 3866666666666620 [
> > >> 230.457306] f8e0: ffffff800a1b4065 0000000000000006 ffffff800a129000
> > >> ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> > >> ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [ 230.457314]
> > >> f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> > >> ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> > >> ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [ 230.457322]
> > >> f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> > >> 0000000060000145
> > >> ** 1 printk messages dropped ** [ 230.457329] [<ffffff8008085720>]
> > >> el1_irq+0xa0/0x100
> > >> ** 9 printk messages dropped ** [ 230.457373] [<ffffff800885ad60>]
> > >> ieee80211_hw_config+0x50/0x290 [ 230.457377] [<ffffff8008863690>]
> > >> ieee80211_scan_work+0x1f8/0x480 [ 230.457383] [<ffffff80080b15d0>]
> > >> process_one_work+0x120/0x378 [ 230.457386] [<ffffff80080b1870>]
> > >> worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> > >> kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> > ret_from_fork+0x10/0x40
> > >> [ 230.480389] ath9k_hw_intrpend 762
> > >>
> > >>
> > >> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [ 545.526189]
> > >> INFO: rcu_sched self-detected stall on CPU
> > >> [ 545.526195] 2-...: (97636 ticks this GP)
> > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> > >> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> > >> [ 545.526201] Task dump for CPU 2:
> > >> [ 545.526206] kworker/u8:4 R running task 0 1342 2 0x00000002
> > >> ** 3 printk messages dropped ** [ 545.526231] [<ffffff8008089a0c>]
> > >> show_stack+0x14/0x20
> > >> ** 9 printk messages dropped ** [ 545.526280] [<ffffff80086a71e8>]
> > >> arch_timer_handler_phys+0x30/0x40 [ 545.526284] [<ffffff80080dbe18>]
> > >> handle_percpu_devid_irq+0x78/0xa0 [ 545.526291] [<ffffff80080d760c>]
> > >> generic_handle_irq+0x24/0x38 [ 545.526296] [<ffffff80080d7944>]
> > >> __handle_domain_irq+0x5c/0xb8 [ 545.526299] [<ffffff80080824bc>]
> > >> gic_handle_irq+0x64/0xc0 [ 545.526302] Exception stack(0xffffffc87b07f870
> > to 0xffffffc87b07f990)
> > >> [ 545.526306] f860: 0000000000009732 ffffff800a1eaaa8
> > >> ** 8 printk messages dropped ** [ 545.526341] f980: ffffff800a1c39e8
> > >> 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> > >> el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> > >> console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> > >> vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> > >> vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> > >> printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> > >> ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> > >> ath9k_hw_kill_interrupts+0x28/0xf0
> > >> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> > >> ** 2 printk messages dropped ** [ 545.526391] [<ffffff800885ad60>]
> > ieee80211_hw_config+0x50/0x290
> > >> ** 11 printk messages dropped ** [ 545.532834] ath9k_hw_kill_interrupts
> > 793
> > >> [ 545.532890] ath9k_hw_enable_interrupts 821
> >
> > [ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
> > [ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
> > [ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
> > [ 81.876936] swapper/4 R running task 0 0 1
> > 0x00000000
> > [ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > ffffffff81a3dc40
> > [ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > ffffffff81a3dc40
> > [ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
> > ffff88017edbc240
> > [ 81.876951] Call Trace:
> > [ 81.876970] <IRQ>
> > [ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > [ 81.876983] [<ffffffff81101e46>] ?
> > rcu_print_detail_task_stall_rnp+0x40/0x61
> > [ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
> > [ 81.876993] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> > [ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > [ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > [ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > [ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > [ 81.877008] [<ffffffff81031b1e>] ?
> > smp_trace_apic_timer_interrupt+0x5e/0x90
> > [ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > [ 81.877013] <EOI>
> > [ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > [ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > [ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > [ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > [ 81.877029] swapper/4 R running task 0 0 1
> > 0x00000000
> > [ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > ffffffff81a3dc40
> > [ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > ffffffff81a3dc40
> > [ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
> > ffff88017edbc240
> > [ 81.877041] Call Trace:
> > [ 81.877045] <IRQ>
> > [ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > [ 81.877051] [<ffffffff81101e46>] ?
> > rcu_print_detail_task_stall_rnp+0x40/0x61
> > [ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
> > [ 81.877058] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> > [ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > [ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > [ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > [ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > [ 81.877070] [<ffffffff81031b1e>] ?
> > smp_trace_apic_timer_interrupt+0x5e/0x90
> > [ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > [ 81.877074] <EOI>
> > [ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > [ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > [ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > [ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > [ 91.132787] INFO: rcu_preempt detected expedited stalls on
> > CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
> > [ 91.132796] blocking rcu_node structures:
> >
> > >>
> > >>
> > >> But if we have less debug prints it does not reach EP handler
> > >> sometimes, due to following Condition in "kernel/irq/chip.c" in
> > >> function handle_simple_irq
> > >>
> > >> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> > >> desc->istate |= IRQS_PENDING;
> > >> goto out_unlock;
> > >> }
> > >> Here irqd_irq_disabled is being set to 1.
> > >>
> > >> With lesser debug prints it stops after following prints:
> > >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> > >> [ 54.781045] ath9k_hw_kill_interrupts 793
> > >> [ 54.785007] ath9k_hw_kill_interrupts 793
> > >> [ 54.792535] ath9k_hw_enable_interrupts 821
> > >> [ 54.796642] ath9k_hw_enable_interrupts 825
> > >> [ 54.800807] ath9k_hw_enable_interrupts 832
> > >> [ 54.804973] AR_SREV_9100 0
> > >> [ 54.807663] ath9k_hw_enable_interrupts 848
> > >> [ 54.811843] ath9k_hw_intrpend 762
> > >> [ 54.815211] (AR_SREV_9340(ah) val 0
> > >> [ 54.818684] ath9k_hw_intrpend 767
> > >> [ 54.822078] ath_isr 603
> > >> [ 54.824587] ath9k_hw_kill_interrupts 793
> > >> [ 54.828601] ath9k_hw_enable_interrupts 821
> > >> [ 54.832750] ath9k_hw_enable_interrupts 825
> > >> [ 54.836916] ath9k_hw_enable_interrupts 832
> > >> [ 54.841082] AR_SREV_9100 0
> > >> [ 54.843772] ath9k_hw_enable_interrupts 848
> > >> [ 54.843775] ath9k_hw_intrpend 762
> > >> [ 54.851319] (AR_SREV_9340(ah) val 0
> > >> [ 54.854793] ath9k_hw_intrpend 767
> > >> [ 54.858185] ath_isr 603
> > >> [ 54.860696] ath9k_hw_kill_interrupts 793
> > >> [ 54.864776] ath9k_hw_enable_interrupts 821
> > >> [ 54.867061] ath9k_hw_kill_interrupts 793
> > >> [ 54.872870] ath9k_hw_enable_interrupts 825
> > >> [ 54.877036] ath9k_hw_enable_interrupts 832
> > >> [ 54.881202] AR_SREV_9100 0
> > >> [ 54.883892] ath9k_hw_enable_interrupts 848
> > >> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> > >> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > softirq=1103/1109 fqs=519
> > >> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> > >> [ 75.982485] Task dump for CPU 0:
> > >> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> > >> [ 75.992726] Call trace:
> > >> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> > >> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> > >> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> > >> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > softirq=1103/1109 fqs=2097
> > >> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> > >> [ 139.078489] Task dump for CPU 0:
> > >> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> > >> [ 139.088731] Call trace:
> > >> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> > >> 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> > >>
> > >>
> > >>>> We are not seeing any issues on 32-bit ARM platform and X86
> > >>>> platform.
> > >>> Can you collect a dmesg log (or, if the system hang means you can't
> > >>> collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> > >>> output as root? That should have clues about whether the INTx got
> > >>> routed correctly. /proc/interrupts should also show whether we're
> > >>> receiving interrupts from the device.
> > >> Here is the lspci output:
> > >> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00 [Normal
> > decode])
> > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > >> Latency: 0
> > >> Interrupt: pin A routed to IRQ 224
> > >> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> > >> I/O behind bridge: 00000000-00000fff
> > >> Memory behind bridge: e0000000-e00fffff
> > >> Prefetchable memory behind bridge: 00000000fff00000-
> > 00000000000fffff
> > >> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- <SERR- <PERR-
> > >> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> > >> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> > >> Capabilities: [40] Power Management version 3
> > >> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> > PME(D0+,D1+,D2+,D3hot+,D3cold-)
> > >> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> > >> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> > >> DevCap: MaxPayload 256 bytes, PhantFunc 0
> > >> ExtTag- RBE+
> > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > Unsupported-
> > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > TransPend+
> > >> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> > Exit Latency L0s unlimited, L1 unlimited
> > >> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > DLActive- BWMgmt- ABWMgmt-
> > >> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> > CRSVisible+
> > >> RootCap: CRSVisible+
> > >> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> > >> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> > OBFF Not Supported ARIFwd-
> > >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > OBFF Disabled ARIFwd-
> > >> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> > >> Transmit Margin: Normal Operating Range,
> > EnterModifiedCompliance- ComplianceSOS-
> > >> Compliance De-emphasis: -6dB
> > >> LnkSta2: Current De-emphasis Level: -3.5dB,
> > EqualizationComplete-, EqualizationPhase1-
> > >> EqualizationPhase2-, EqualizationPhase3-,
> > LinkEqualizationRequest-
> > >> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > >> Capabilities: [10c v1] Virtual Channel
> > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > >> Ctrl: ArbSelect=Fixed
> > >> Status: InProgress-
> > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > WRR256-
> > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > >> Status: NegoPending- InProgress-
> > >> Capabilities: [128 v1] Vendor Specific Information: ID=1234 Rev=1
> > >> Len=018 <?>
> > >>
> > >> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network
> > Adapter (rev 01)
> > >> Subsystem: Qualcomm Atheros Device 3112
> > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > >> Latency: 0, Cache Line Size: 128 bytes
> > >> Interrupt: pin A routed to IRQ 224
> > >> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> > >> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> > >> Capabilities: [40] Power Management version 3
> > >> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> > PME(D0+,D1+,D2-,D3hot+,D3cold-)
> > >> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> > >> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> > >> Address: 0000000000000000 Data: 0000
> > >> Masking: 00000000 Pending: 00000000
> > >> Capabilities: [70] Express (v2) Endpoint, MSI 00
> > >> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> > L0s <1us, L1 <8us
> > >> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> > SlotPowerLimit 0.000W
> > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > Unsupported-
> > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > TransPend-
> > >> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> > Latency L0s <2us, L1 <64us
> > >> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > DLActive- BWMgmt- ABWMgmt-
> > >> DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> > LTR-, OBFF Not Supported
> > >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > OBFF Disabled
> > >> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> > SpeedDis-
> > >> Transmit Margin: Normal Operating Range,
> > EnterModifiedCompliance- ComplianceSOS-
> > >> Compliance De-emphasis: -6dB
> > >> LnkSta2: Current De-emphasis Level: -6dB,
> > EqualizationComplete-, EqualizationPhase1-
> > >> EqualizationPhase2-, EqualizationPhase3-,
> > LinkEqualizationRequest-
> > >> Capabilities: [100 v1] Advanced Error Reporting
> > >> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > >> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > >> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> > RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> > >> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > NonFatalErr-
> > >> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > NonFatalErr+
> > >> AERCap: First Error Pointer: 00, GenCap- CGenEn-
> > ChkCap- ChkEn-
> > >> Capabilities: [140 v1] Virtual Channel
> > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > >> Ctrl: ArbSelect=Fixed
> > >> Status: InProgress-
> > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > WRR256-
> > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > >> Status: NegoPending- InProgress-
> > >> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > >> Kernel driver in use: ath9k
> > >>
> > >> Here is the cat /proc/interrupts (after we do interface up):
> > >>
> > >> root@:~# ifconfig wlan0 up
> > >> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
> > >> root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > >> CPU0 CPU1 CPU2 CPU3
> > >> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > >> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> > >> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > >> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > >> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > >> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > >> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > >> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > >> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > >> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > >> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> > Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > >> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > >> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > >> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > >> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > >> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > >> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > >> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > >> 217: 0 0 0 0 GICv2 165 Level ahci-
> > ceva[fd0c0000.ahci]
> > >> 218: 61 0 0 0 GICv2 81 Level mmc0
> > >> 219: 0 0 0 0 GICv2 187 Level arm-smmu global fault
> > >> 220: 471 0 0 0 GICv2 53 Level xuartps
> > >> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > >> 224: 3 0 0 0 dummy 1 Edge ath9k
> > >> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> > >>
> > >> Regards,
> > >> Bharat
>

2016-12-14 05:43:49

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

> On Sat, Dec 10, 2016 at 02:40:48PM +0000, Bharat Kumar Gogada wrote:
> > Hi,
> >
> > After taking some more lecroy traces, we see that after 2nd ASSERT from EP
> on ARM64 we see continuous data movement of 32 dwords or 12 dwords and
> never sign of DEASSERT.
> > Comparatively on working traces (x86) after 2nd assert there are only BAR
> register reads and writes and then DEASSERT, for almost most of the interrupts
> and we haven't seen 12 or 32 dwords data movement on this trace.
> >
> > I did not work on EP wifi/network drivers, any help why EP needs those many
> number of data at scan time ?
>
> The device doesn't know whether it's in an x86 or an arm64 system. If it works
> differently, it must be because the PCI core or the driver is programming the
> device differently.
>
> You should be able to match up Memory transactions from the host in the trace
> with things the driver does. For example, if you see an Assert_INTx message
> from the device, you should eventually see a Memory Read from the host to get
> the ISR, i.e., some read done in the bowels of ath9k_hw_getisr().
>
> I don't know how the ath9k device works, but there must be some Memory Read
> or Write done by the driver that tells the device "we've handled this interrupt".
> The device should then send a Deassert_INTx; of course, if the device still
> requires service, e.g., because it has received more packets, it might leave the
> INTx asserted.
>
> I doubt you'd see exactly the same traces on x86 and arm64 because they aren't
> seeing the same network packets and the driver is executing at different rates.
> But you should at least be able to identify interrupt assertion and the actions of
> the driver's interrupt service routine.


Thanks Bjorn.

As you mentioned we did try to debug in that path. After we start scan after 2nd ASSERT we see lots of 32 and 12 dword
data, and in function
void ath9k_hw_enable_interrupts(struct ath_hw *ah)
{
...
..
REG_WRITE(ah, AR_IER, AR_IER_ENABLE);
// EP driver hangs at this position after 2nd ASSERT
// The following writes are not happening
if (!AR_SREV_9100(ah)) {
REG_WRITE(ah, AR_INTR_ASYNC_ENABLE, async_mask);
REG_WRITE(ah, AR_INTR_ASYNC_MASK, async_mask);

REG_WRITE(ah, AR_INTR_SYNC_ENABLE, sync_default);
REG_WRITE(ah, AR_INTR_SYNC_MASK, sync_default);
}
ath_dbg(common, INTERRUPT, "AR_IMR 0x%x IER 0x%x\n",
REG_READ(ah, AR_IMR), REG_READ(ah, AR_IER));
}
The above funtion is invoked from tasklet.
I tried several boots every it stops here. The condition (!AR_SREV_9100(ah)) is true as per before 1st ASSERT handling.

Regards,
Bharat

>
> > > Hello there,
> > >
> > > as this is a thread about ath9k and ARM64, i'm not sure if i should
> > > answer here or not, but i have similar "stalls" with ath9k on x86_64
> > > (starting with 4.9rc), stack trace is posted down below where the original
> ARM64 stall traces are.
> > >
> > > Greetings,
> > >
> > > Tobias
> > >
> > >
> > > On 08.12.2016 18:36, Kalle Valo wrote:
> > > > Bharat Kumar Gogada <[email protected]> writes:
> > > >
> > > >> > [+cc Kalle, ath9k list]
> > > > Thanks, but please also CC linux-wireless. Full thread below for
> > > > the folks there.
> > > >
> > > >>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada
> wrote:
> > > >>>> Hi,
> > > >>>>
> > > >>>> Did anyone test Atheros ATH9
> > > >>>> driver(drivers/net/wireless/ath/ath9k/)
> > > >>>> on ARM64. The end point is TP link wifi card with which
> > > >>>> supports only legacy interrupts.
> > > >>> If it works on other arches and the arm64 PCI enumeration works,
> > > >>> my first guess would be an INTx issue, e.g., maybe the driver is
> > > >>> waiting for an interrupt that never arrives.
> > > >> We are not sure for now.
> > > >>>> We are trying to test it on ARM64 with
> > > >>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> > > >>>>
> > > >>>> EP is getting enumerated and able to link up.
> > > >>>>
> > > >>>> But when we start scan system gets hanged.
> > > >>> When you say the system hangs when you start a scan, I assume
> > > >>> you mean a wifi scan, not the PCI enumeration. A problem with a
> > > >>> wifi scan might cause a *process* to hang, but it shouldn't hang
> > > >>> the entire system.
> > > >>>
> > > >> Yes wifi scan.
> > > >>>> When we took trace we see that after we start scan assert
> > > >>>> message is sent but there is no de assert from end point.
> > > >>> Are you talking about a trace from a PCIe analyzer? Do you see
> > > >>> an Assert_INTx PCIe message on the link?
> > > >>>
> > > >> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx
> > > >> happening
> > > when we do interface link up.
> > > >> When we have less debug prints in Atheros driver, and do wifi
> > > >> scan we see Assert_INTx but never Deassert_INTx,
> > > >>>> What might cause end point not sending de assert ?
> > > >>> If the endpoint doesn't send a Deassert_INTx message, I expect
> > > >>> that would mean the driver didn't service the interrupt and
> > > >>> remove the condition that caused the device to assert the
> > > >>> interrupt in the first place.
> > > >>>
> > > >>> If the driver didn't receive the interrupt, it couldn't service
> > > >>> it, of course. You could add a printk in the ath9k interrupt
> > > >>> service routine to see if you ever get there.
> > > >>>
> > > >> The interrupt behavior is changing w.r.t amount of debug prints
> > > >> we add. (I kept many prints to aid debug)
> > > >> root@Xilinx-ZCU102-2016_3:~# iw dev
> > > wlan0 scan
> > > >> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.074257] ath9k_hw_kill_interrupts 793
> > > >> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.087882] ath9k_hw_kill_interrupts 793
> > > >> [ 83.095450] ath9k_hw_enable_interrupts 821
> > > >> [ 83.099557] ath9k_hw_enable_interrupts 825
> > > >> [ 83.103721] ath9k_hw_enable_interrupts 832
> > > >> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.112748] AR_SREV_9100 0
> > > >> [ 83.115438] ath9k_hw_enable_interrupts 848
> > > >> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.124389] ath9k_hw_intrpend 762
> > > >> [ 83.127761] (AR_SREV_9340(ah) val 0
> > > >> [ 83.131234] ath9k_hw_intrpend 767
> > > >> [ 83.134628] ath_isr 603
> > > >> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.146771] ath9k_hw_kill_interrupts 793
> > > >> [ 83.150864] ath9k_hw_enable_interrupts 821
> > > >> [ 83.154971] ath9k_hw_enable_interrupts 825
> > > >> [ 83.159135] ath9k_hw_enable_interrupts 832
> > > >> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.168161] AR_SREV_9100 0
> > > >> [ 83.170852] ath9k_hw_enable_interrupts 848
> > > >> [ 83.170855] ath9k_hw_intrpend 762
> > > >> [ 83.178398] (AR_SREV_9340(ah) val 0
> > > >> [ 83.181873] ath9k_hw_intrpend 767
> > > >> [ 83.185265] ath_isr 603
> > > >> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.197411] ath9k_hw_kill_interrupts 793
> > > >> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.206258] ath9k_hw_enable_interrupts 821
> > > >> [ 83.210368] ath9k_hw_enable_interrupts 825
> > > >> [ 83.214531] ath9k_hw_enable_interrupts 832
> > > >> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.223558] AR_SREV_9100 0
> > > >> [ 83.226243] ath9k_hw_enable_interrupts 848
> > > >> [ 83.226246] ath9k_hw_intrpend 762
> > > >> [ 83.233794] (AR_SREV_9340(ah) val 0
> > > >> [ 83.237268] ath9k_hw_intrpend 767
> > > >> [ 83.240661] ath_isr 603
> > > >> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.252806] ath9k_hw_kill_interrupts 793
> > > >> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.261651] ath9k_hw_enable_interrupts 821
> > > >> [ 83.265753] ath9k_hw_enable_interrupts 825
> > > >> [ 83.269919] ath9k_hw_enable_interrupts 832
> > > >> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.278945] AR_SREV_9100 0
> > > >> [ 83.281630] ath9k_hw_enable_interrupts 848
> > > >> [ 83.281633] ath9k_hw_intrpend 762
> > > >> [ 83.281634] (AR_SREV_9340(ah) val 0
> > > >> [ 83.281637] ath9k_hw_intrpend 767
> > > >> [ 83.281648] ath_isr 603
> > > >> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.281654] ath9k_hw_kill_interrupts 793
> > > >> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> > > >> [ 83.317030] ath9k_hw_enable_interrupts 821
> > > >> [ 83.321132] ath9k_hw_enable_interrupts 825
> > > >> [ 83.325297] ath9k_hw_enable_interrupts 832
> > > >> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> > > >> [ 83.334324] AR_SREV_9100 0
> > > >> [ 83.337014] ath9k_hw_enable_interrupts 848
> > > >> ..
> > > >> ..
> > > >> This log continues until I turn off board without obtaining scanning result.
> > > >>
> > > >> In between I get following cpu stall outputs :
> > > >> 230.457179] INFO: rcu_sched self-detected stall on CPU
> > > >> [ 230.457185] 2-...: (31314 ticks this GP)
> > > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> > > >> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> > > >> [ 230.457191] Task dump for CPU 2:
> > > >> [ 230.457196] kworker/u8:4 R running task 0 1342 2
> 0x00000002
> > > >> [ 230.457207] Workqueue: phy0 ieee80211_scan_work [ 230.457208]
> > > >> Call trace:
> > > >> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> > > >> 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [
> > > >> 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [
> > > >> 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [
> > > >> 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0 [
> > > >> 230.457239] [<ffffff80080e4cd8>] rcu_check_callbacks+0x468/0x748
> > > >> [ 230.457243] [<ffffff80080e7cfc>]
> > > >> update_process_times+0x3c/0x68 [ 230.457249]
> > > >> [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> > > >> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90 [
> > > >> 230.457257] [<ffffff80080e86b0>] __hrtimer_run_queues+0xf0/0x178
> > > >> ** 10 printk messages dropped ** [ 230.457302] f8c0:
> > > >> 0000000000000000 0000000005f5e0ff 000000000001379a
> > > 3866666666666620 [
> > > >> 230.457306] f8e0: ffffff800a1b4065 0000000000000006
> > > >> ffffff800a129000
> > > >> ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> > > >> ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [ 230.457314]
> > > >> f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> > > >> ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> > > >> ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [ 230.457322]
> > > >> f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> > > >> 0000000060000145
> > > >> ** 1 printk messages dropped ** [ 230.457329]
> > > >> [<ffffff8008085720>]
> > > >> el1_irq+0xa0/0x100
> > > >> ** 9 printk messages dropped ** [ 230.457373]
> > > >> [<ffffff800885ad60>]
> > > >> ieee80211_hw_config+0x50/0x290 [ 230.457377]
> > > >> [<ffffff8008863690>]
> > > >> ieee80211_scan_work+0x1f8/0x480 [ 230.457383]
> > > >> [<ffffff80080b15d0>]
> > > >> process_one_work+0x120/0x378 [ 230.457386] [<ffffff80080b1870>]
> > > >> worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> > > >> kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> > > ret_from_fork+0x10/0x40
> > > >> [ 230.480389] ath9k_hw_intrpend 762
> > > >>
> > > >>
> > > >> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [
> > > >> 545.526189]
> > > >> INFO: rcu_sched self-detected stall on CPU
> > > >> [ 545.526195] 2-...: (97636 ticks this GP)
> > > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> > > >> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> > > >> [ 545.526201] Task dump for CPU 2:
> > > >> [ 545.526206] kworker/u8:4 R running task 0 1342 2
> 0x00000002
> > > >> ** 3 printk messages dropped ** [ 545.526231]
> > > >> [<ffffff8008089a0c>]
> > > >> show_stack+0x14/0x20
> > > >> ** 9 printk messages dropped ** [ 545.526280]
> > > >> [<ffffff80086a71e8>]
> > > >> arch_timer_handler_phys+0x30/0x40 [ 545.526284]
> > > >> [<ffffff80080dbe18>]
> > > >> handle_percpu_devid_irq+0x78/0xa0 [ 545.526291]
> > > >> [<ffffff80080d760c>]
> > > >> generic_handle_irq+0x24/0x38 [ 545.526296] [<ffffff80080d7944>]
> > > >> __handle_domain_irq+0x5c/0xb8 [ 545.526299] [<ffffff80080824bc>]
> > > >> gic_handle_irq+0x64/0xc0 [ 545.526302] Exception
> > > >> stack(0xffffffc87b07f870
> > > to 0xffffffc87b07f990)
> > > >> [ 545.526306] f860: 0000000000009732
> ffffff800a1eaaa8
> > > >> ** 8 printk messages dropped ** [ 545.526341] f980:
> > > >> ffffff800a1c39e8
> > > >> 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> > > >> el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> > > >> console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> > > >> vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> > > >> vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> > > >> printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> > > >> ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> > > >> ath9k_hw_kill_interrupts+0x28/0xf0
> > > >> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> > > >> ** 2 printk messages dropped ** [ 545.526391]
> > > >> [<ffffff800885ad60>]
> > > ieee80211_hw_config+0x50/0x290
> > > >> ** 11 printk messages dropped ** [ 545.532834]
> > > >> ath9k_hw_kill_interrupts
> > > 793
> > > >> [ 545.532890] ath9k_hw_enable_interrupts 821
> > >
> > > [ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
> > > [ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
> > > [ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
> > > [ 81.876936] swapper/4 R running task 0 0 1
> > > 0x00000000
> > > [ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > > ffffffff81a3dc40
> > > [ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > > ffffffff81a3dc40
> > > [ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
> > > ffff88017edbc240
> > > [ 81.876951] Call Trace:
> > > [ 81.876970] <IRQ>
> > > [ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > > [ 81.876983] [<ffffffff81101e46>] ?
> > > rcu_print_detail_task_stall_rnp+0x40/0x61
> > > [ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
> > > [ 81.876993] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> > > [ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > > [ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > > [ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > > [ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > > [ 81.877008] [<ffffffff81031b1e>] ?
> > > smp_trace_apic_timer_interrupt+0x5e/0x90
> > > [ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > > [ 81.877013] <EOI>
> > > [ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > > [ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > > [ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > > [ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > > [ 81.877029] swapper/4 R running task 0 0 1
> > > 0x00000000
> > > [ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > > ffffffff81a3dc40
> > > [ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > > ffffffff81a3dc40
> > > [ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
> > > ffff88017edbc240
> > > [ 81.877041] Call Trace:
> > > [ 81.877045] <IRQ>
> > > [ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > > [ 81.877051] [<ffffffff81101e46>] ?
> > > rcu_print_detail_task_stall_rnp+0x40/0x61
> > > [ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
> > > [ 81.877058] [<ffffffff810b8350>] ? tick_sched_handle.isra.14+0x40/0x40
> > > [ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > > [ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > > [ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > > [ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > > [ 81.877070] [<ffffffff81031b1e>] ?
> > > smp_trace_apic_timer_interrupt+0x5e/0x90
> > > [ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > > [ 81.877074] <EOI>
> > > [ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > > [ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > > [ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > > [ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > > [ 91.132787] INFO: rcu_preempt detected expedited stalls on
> > > CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
> > > [ 91.132796] blocking rcu_node structures:
> > >
> > > >>
> > > >>
> > > >> But if we have less debug prints it does not reach EP handler
> > > >> sometimes, due to following Condition in "kernel/irq/chip.c" in
> > > >> function handle_simple_irq
> > > >>
> > > >> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> > > >> desc->istate |= IRQS_PENDING;
> > > >> goto out_unlock;
> > > >> }
> > > >> Here irqd_irq_disabled is being set to 1.
> > > >>
> > > >> With lesser debug prints it stops after following prints:
> > > >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> > > >> [ 54.781045] ath9k_hw_kill_interrupts 793
> > > >> [ 54.785007] ath9k_hw_kill_interrupts 793
> > > >> [ 54.792535] ath9k_hw_enable_interrupts 821
> > > >> [ 54.796642] ath9k_hw_enable_interrupts 825
> > > >> [ 54.800807] ath9k_hw_enable_interrupts 832
> > > >> [ 54.804973] AR_SREV_9100 0
> > > >> [ 54.807663] ath9k_hw_enable_interrupts 848
> > > >> [ 54.811843] ath9k_hw_intrpend 762
> > > >> [ 54.815211] (AR_SREV_9340(ah) val 0
> > > >> [ 54.818684] ath9k_hw_intrpend 767
> > > >> [ 54.822078] ath_isr 603
> > > >> [ 54.824587] ath9k_hw_kill_interrupts 793
> > > >> [ 54.828601] ath9k_hw_enable_interrupts 821
> > > >> [ 54.832750] ath9k_hw_enable_interrupts 825
> > > >> [ 54.836916] ath9k_hw_enable_interrupts 832
> > > >> [ 54.841082] AR_SREV_9100 0
> > > >> [ 54.843772] ath9k_hw_enable_interrupts 848
> > > >> [ 54.843775] ath9k_hw_intrpend 762
> > > >> [ 54.851319] (AR_SREV_9340(ah) val 0
> > > >> [ 54.854793] ath9k_hw_intrpend 767
> > > >> [ 54.858185] ath_isr 603
> > > >> [ 54.860696] ath9k_hw_kill_interrupts 793
> > > >> [ 54.864776] ath9k_hw_enable_interrupts 821
> > > >> [ 54.867061] ath9k_hw_kill_interrupts 793
> > > >> [ 54.872870] ath9k_hw_enable_interrupts 825
> > > >> [ 54.877036] ath9k_hw_enable_interrupts 832
> > > >> [ 54.881202] AR_SREV_9100 0
> > > >> [ 54.883892] ath9k_hw_enable_interrupts 848
> > > >> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > >> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > > softirq=1103/1109 fqs=519
> > > >> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> > > >> [ 75.982485] Task dump for CPU 0:
> > > >> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > >> [ 75.992726] Call trace:
> > > >> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> > > >> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> > > >> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > >> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > > softirq=1103/1109 fqs=2097
> > > >> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> > > >> [ 139.078489] Task dump for CPU 0:
> > > >> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > >> [ 139.088731] Call trace:
> > > >> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> > > >> 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> > > >>
> > > >>
> > > >>>> We are not seeing any issues on 32-bit ARM platform and X86
> > > >>>> platform.
> > > >>> Can you collect a dmesg log (or, if the system hang means you
> > > >>> can't collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> > > >>> output as root? That should have clues about whether the INTx
> > > >>> got routed correctly. /proc/interrupts should also show whether
> > > >>> we're receiving interrupts from the device.
> > > >> Here is the lspci output:
> > > >> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00
> > > >> [Normal
> > > decode])
> > > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > >> Latency: 0
> > > >> Interrupt: pin A routed to IRQ 224
> > > >> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> > > >> I/O behind bridge: 00000000-00000fff
> > > >> Memory behind bridge: e0000000-e00fffff
> > > >> Prefetchable memory behind bridge: 00000000fff00000-
> > > 00000000000fffff
> > > >> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > > <TAbort- <MAbort- <SERR- <PERR-
> > > >> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> > > >> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> > > >> Capabilities: [40] Power Management version 3
> > > >> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> > > PME(D0+,D1+,D2+,D3hot+,D3cold-)
> > > >> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
> > > >> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> > > >> DevCap: MaxPayload 256 bytes, PhantFunc 0
> > > >> ExtTag- RBE+
> > > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > > Unsupported-
> > > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
> > > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > > TransPend+
> > > >> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not supported,
> > > Exit Latency L0s unlimited, L1 unlimited
> > > >> ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
> > > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > > >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > > DLActive- BWMgmt- ABWMgmt-
> > > >> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna-
> > > CRSVisible+
> > > >> RootCap: CRSVisible+
> > > >> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> > > >> DevCap2: Completion Timeout: Range B, TimeoutDis+, LTR-,
> > > OBFF Not Supported ARIFwd-
> > > >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > > OBFF Disabled ARIFwd-
> > > >> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
> > > >> Transmit Margin: Normal Operating Range,
> > > EnterModifiedCompliance- ComplianceSOS-
> > > >> Compliance De-emphasis: -6dB
> > > >> LnkSta2: Current De-emphasis Level: -3.5dB,
> > > EqualizationComplete-, EqualizationPhase1-
> > > >> EqualizationPhase2-, EqualizationPhase3-,
> > > LinkEqualizationRequest-
> > > >> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > > >> Capabilities: [10c v1] Virtual Channel
> > > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > > >> Ctrl: ArbSelect=Fixed
> > > >> Status: InProgress-
> > > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > > >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > > WRR256-
> > > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > >> Status: NegoPending- InProgress-
> > > >> Capabilities: [128 v1] Vendor Specific Information: ID=1234
> > > >> Rev=1
> > > >> Len=018 <?>
> > > >>
> > > >> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless
> > > >> Network
> > > Adapter (rev 01)
> > > >> Subsystem: Qualcomm Atheros Device 3112
> > > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> > > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> > > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > >> Latency: 0, Cache Line Size: 128 bytes
> > > >> Interrupt: pin A routed to IRQ 224
> > > >> Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=128K]
> > > >> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> > > >> Capabilities: [40] Power Management version 3
> > > >> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> > > PME(D0+,D1+,D2-,D3hot+,D3cold-)
> > > >> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> > > >> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> > > >> Address: 0000000000000000 Data: 0000
> > > >> Masking: 00000000 Pending: 00000000
> > > >> Capabilities: [70] Express (v2) Endpoint, MSI 00
> > > >> DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency
> > > L0s <1us, L1 <8us
> > > >> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
> > > SlotPowerLimit 0.000W
> > > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > > Unsupported-
> > > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
> > > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
> > > TransPend-
> > > >> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit
> > > Latency L0s <2us, L1 <64us
> > > >> ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
> > > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
> > > >> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> > > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > > DLActive- BWMgmt- ABWMgmt-
> > > >> DevCap2: Completion Timeout: Not Supported, TimeoutDis+,
> > > LTR-, OBFF Not Supported
> > > >> DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-,
> > > OBFF Disabled
> > > >> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> > > SpeedDis-
> > > >> Transmit Margin: Normal Operating Range,
> > > EnterModifiedCompliance- ComplianceSOS-
> > > >> Compliance De-emphasis: -6dB
> > > >> LnkSta2: Current De-emphasis Level: -6dB,
> > > EqualizationComplete-, EqualizationPhase1-
> > > >> EqualizationPhase2-, EqualizationPhase3-,
> > > LinkEqualizationRequest-
> > > >> Capabilities: [100 v1] Advanced Error Reporting
> > > >> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > >> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt-
> > > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > >> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt-
> > > RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> > > >> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > > NonFatalErr-
> > > >> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > > NonFatalErr+
> > > >> AERCap: First Error Pointer: 00, GenCap- CGenEn-
> > > ChkCap- ChkEn-
> > > >> Capabilities: [140 v1] Virtual Channel
> > > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > > >> Ctrl: ArbSelect=Fixed
> > > >> Status: InProgress-
> > > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
> > > >> Arb: Fixed- WRR32- WRR64- WRR128- TWRR128-
> > > WRR256-
> > > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > >> Status: NegoPending- InProgress-
> > > >> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00
> > > >> Kernel driver in use: ath9k
> > > >>
> > > >> Here is the cat /proc/interrupts (after we do interface up):
> > > >>
> > > >> root@:~# ifconfig wlan0 up
> > > >> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not
> > > >> ready root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > > >> CPU0 CPU1 CPU2 CPU3
> > > >> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > > >> 2: 19873 20058 19089 17435 GICv2 30 Edge arch_timer
> > > >> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > > >> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > > >> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > > >> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > > >> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > > >> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > > >> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > > >> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > > >> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> > > Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > > >> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > > >> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > > >> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > > >> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > > >> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > > >> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > > >> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > > >> 217: 0 0 0 0 GICv2 165 Level ahci-
> > > ceva[fd0c0000.ahci]
> > > >> 218: 61 0 0 0 GICv2 81 Level mmc0
> > > >> 219: 0 0 0 0 GICv2 187 Level arm-smmu global
> fault
> > > >> 220: 471 0 0 0 GICv2 53 Level xuartps
> > > >> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > > >> 224: 3 0 0 0 dummy 1 Edge ath9k
> > > >> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> > > >>
> > > >> Regards,
> > > >> Bharat
> >

2016-12-22 07:19:38

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: ATH9 driver issues on ARM64

Hi All,

After further debugging we know the place it hangs.

In function:
static int ath_reset_internal (struct ath_softc *sc, struct ath9k_channel *hchan)
{
disable_irq(sc->irq);
tasklet_disable(&sc->intr_tq);
tasklet_disable(&sc->bcon_tasklet);
spin_lock_bh(&sc->sc_pcu_lock);
....
....
....
if (!ath_complete_reset(sc, true)) -> This function enables hardware interrupts
r = -EIO;

out:
enable_irq(sc->irq); -> Here IRQ line state is changed to enable state
spin_unlock_bh(&sc->sc_pcu_lock);
tasklet_enable(&sc->bcon_tasklet);
tasklet_enable(&sc->intr_tq);

}

static bool ath_complete_reset(struct ath_softc *sc, bool start)
{
struct ath_hw *ah = sc->sc_ah;
struct ath_common *common = ath9k_hw_common(ah);
unsigned long flags;

ath9k_calculate_summary_state(sc, sc->cur_chan);
ath_startrecv(sc);
....
....

sc->gtt_cnt = 0;

ath9k_hw_set_interrupts(ah); -> Here hardware interrupts are being enabled
ath9k_hw_enable_interrupts(ah); -> We see hang after this line
ieee80211_wake_queues(sc->hw);
ath9k_p2p_ps_timer(sc);

return true;
}

Before changing IRQ line to to enabled state, hardware interrupts are being enabled.
Wont this cause a race condition where within this period of hardware raises an interrupt, but IRQ line state is disabled state, this will
reach the following condition making EP handler not being invoked.

void handle_simple_irq(struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
...
if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { // This condition is reaching and becoming true.
desc->istate |= IRQS_PENDING;
goto out_unlock;
}

kstat_incr_irqs_this_cpu(desc);
handle_irq_event(desc);

out_unlock:
raw_spin_unlock(&desc->lock);
}

We see hang at that statement, without reaching back enable_irq, looks like by this time CPU is in stall.

Can any tell why hardware interrupts are being enabled before kernel changing IRQ line state?


Regards,
Bharat

>
> > On Sat, Dec 10, 2016 at 02:40:48PM +0000, Bharat Kumar Gogada wrote:
> > > Hi,
> > >
> > > After taking some more lecroy traces, we see that after 2nd ASSERT
> > > from EP
> > on ARM64 we see continuous data movement of 32 dwords or 12 dwords and
> > never sign of DEASSERT.
> > > Comparatively on working traces (x86) after 2nd assert there are
> > > only BAR
> > register reads and writes and then DEASSERT, for almost most of the
> > interrupts and we haven't seen 12 or 32 dwords data movement on this trace.
> > >
> > > I did not work on EP wifi/network drivers, any help why EP needs
> > > those many
> > number of data at scan time ?
> >
> > The device doesn't know whether it's in an x86 or an arm64 system. If
> > it works differently, it must be because the PCI core or the driver is
> > programming the device differently.
> >
> > You should be able to match up Memory transactions from the host in
> > the trace with things the driver does. For example, if you see an
> > Assert_INTx message from the device, you should eventually see a
> > Memory Read from the host to get the ISR, i.e., some read done in the bowels
> of ath9k_hw_getisr().
> >
> > I don't know how the ath9k device works, but there must be some Memory
> > Read or Write done by the driver that tells the device "we've handled this
> interrupt".
> > The device should then send a Deassert_INTx; of course, if the device
> > still requires service, e.g., because it has received more packets, it
> > might leave the INTx asserted.
> >
> > I doubt you'd see exactly the same traces on x86 and arm64 because
> > they aren't seeing the same network packets and the driver is executing at
> different rates.
> > But you should at least be able to identify interrupt assertion and
> > the actions of the driver's interrupt service routine.
>
>
> Thanks Bjorn.
>
> As you mentioned we did try to debug in that path. After we start scan after 2nd
> ASSERT we see lots of 32 and 12 dword data, and in function void
> ath9k_hw_enable_interrupts(struct ath_hw *ah) {
> ...
> ..
> REG_WRITE(ah, AR_IER, AR_IER_ENABLE);
> // EP driver hangs at this
> position after 2nd ASSERT
> // The following writes are not
> happening
> if (!AR_SREV_9100(ah)) {
> REG_WRITE(ah, AR_INTR_ASYNC_ENABLE, async_mask);
> REG_WRITE(ah, AR_INTR_ASYNC_MASK, async_mask);
>
> REG_WRITE(ah, AR_INTR_SYNC_ENABLE, sync_default);
> REG_WRITE(ah, AR_INTR_SYNC_MASK, sync_default);
> }
> ath_dbg(common, INTERRUPT, "AR_IMR 0x%x IER 0x%x\n",
> REG_READ(ah, AR_IMR), REG_READ(ah, AR_IER)); } The above funtion
> is invoked from tasklet.
> I tried several boots every it stops here. The condition (!AR_SREV_9100(ah)) is
> true as per before 1st ASSERT handling.
>
> Regards,
> Bharat
>
> >
> > > > Hello there,
> > > >
> > > > as this is a thread about ath9k and ARM64, i'm not sure if i
> > > > should answer here or not, but i have similar "stalls" with ath9k
> > > > on x86_64 (starting with 4.9rc), stack trace is posted down below
> > > > where the original
> > ARM64 stall traces are.
> > > >
> > > > Greetings,
> > > >
> > > > Tobias
> > > >
> > > >
> > > > On 08.12.2016 18:36, Kalle Valo wrote:
> > > > > Bharat Kumar Gogada <[email protected]> writes:
> > > > >
> > > > >> > [+cc Kalle, ath9k list]
> > > > > Thanks, but please also CC linux-wireless. Full thread below for
> > > > > the folks there.
> > > > >
> > > > >>> On Thu, Dec 08, 2016 at 01:49:42PM +0000, Bharat Kumar Gogada
> > wrote:
> > > > >>>> Hi,
> > > > >>>>
> > > > >>>> Did anyone test Atheros ATH9
> > > > >>>> driver(drivers/net/wireless/ath/ath9k/)
> > > > >>>> on ARM64. The end point is TP link wifi card with which
> > > > >>>> supports only legacy interrupts.
> > > > >>> If it works on other arches and the arm64 PCI enumeration
> > > > >>> works, my first guess would be an INTx issue, e.g., maybe the
> > > > >>> driver is waiting for an interrupt that never arrives.
> > > > >> We are not sure for now.
> > > > >>>> We are trying to test it on ARM64 with
> > > > >>>> (drivers/pci/host/pcie-xilinx-nwl.c) as root port.
> > > > >>>>
> > > > >>>> EP is getting enumerated and able to link up.
> > > > >>>>
> > > > >>>> But when we start scan system gets hanged.
> > > > >>> When you say the system hangs when you start a scan, I assume
> > > > >>> you mean a wifi scan, not the PCI enumeration. A problem with
> > > > >>> a wifi scan might cause a *process* to hang, but it shouldn't
> > > > >>> hang the entire system.
> > > > >>>
> > > > >> Yes wifi scan.
> > > > >>>> When we took trace we see that after we start scan assert
> > > > >>>> message is sent but there is no de assert from end point.
> > > > >>> Are you talking about a trace from a PCIe analyzer? Do you
> > > > >>> see an Assert_INTx PCIe message on the link?
> > > > >>>
> > > > >> Yes lecroy trace, yes we do see Assert_INTx and Deassert_INTx
> > > > >> happening
> > > > when we do interface link up.
> > > > >> When we have less debug prints in Atheros driver, and do wifi
> > > > >> scan we see Assert_INTx but never Deassert_INTx,
> > > > >>>> What might cause end point not sending de assert ?
> > > > >>> If the endpoint doesn't send a Deassert_INTx message, I expect
> > > > >>> that would mean the driver didn't service the interrupt and
> > > > >>> remove the condition that caused the device to assert the
> > > > >>> interrupt in the first place.
> > > > >>>
> > > > >>> If the driver didn't receive the interrupt, it couldn't
> > > > >>> service it, of course. You could add a printk in the ath9k
> > > > >>> interrupt service routine to see if you ever get there.
> > > > >>>
> > > > >> The interrupt behavior is changing w.r.t amount of debug prints
> > > > >> we add. (I kept many prints to aid debug)
> > > > >> root@Xilinx-ZCU102-2016_3:~# iw dev
> > > > wlan0 scan
> > > > >> [ 83.064675] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.069486] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.074257] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.078260] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.083107] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.087882] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.095450] ath9k_hw_enable_interrupts 821
> > > > >> [ 83.099557] ath9k_hw_enable_interrupts 825
> > > > >> [ 83.103721] ath9k_hw_enable_interrupts 832
> > > > >> [ 83.107887] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.112748] AR_SREV_9100 0
> > > > >> [ 83.115438] ath9k_hw_enable_interrupts 848
> > > > >> [ 83.119607] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.124389] ath9k_hw_intrpend 762
> > > > >> [ 83.127761] (AR_SREV_9340(ah) val 0
> > > > >> [ 83.131234] ath9k_hw_intrpend 767
> > > > >> [ 83.134628] ath_isr 603
> > > > >> [ 83.137134] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.141995] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.146771] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.150864] ath9k_hw_enable_interrupts 821
> > > > >> [ 83.154971] ath9k_hw_enable_interrupts 825
> > > > >> [ 83.159135] ath9k_hw_enable_interrupts 832
> > > > >> [ 83.163300] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.168161] AR_SREV_9100 0
> > > > >> [ 83.170852] ath9k_hw_enable_interrupts 848
> > > > >> [ 83.170855] ath9k_hw_intrpend 762
> > > > >> [ 83.178398] (AR_SREV_9340(ah) val 0
> > > > >> [ 83.181873] ath9k_hw_intrpend 767
> > > > >> [ 83.185265] ath_isr 603
> > > > >> [ 83.187773] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.192635] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.197411] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.201414] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.206258] ath9k_hw_enable_interrupts 821
> > > > >> [ 83.210368] ath9k_hw_enable_interrupts 825
> > > > >> [ 83.214531] ath9k_hw_enable_interrupts 832
> > > > >> [ 83.218698] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.223558] AR_SREV_9100 0
> > > > >> [ 83.226243] ath9k_hw_enable_interrupts 848
> > > > >> [ 83.226246] ath9k_hw_intrpend 762
> > > > >> [ 83.233794] (AR_SREV_9340(ah) val 0
> > > > >> [ 83.237268] ath9k_hw_intrpend 767
> > > > >> [ 83.240661] ath_isr 603
> > > > >> [ 83.243169] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.248030] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.252806] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.256811] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.261651] ath9k_hw_enable_interrupts 821
> > > > >> [ 83.265753] ath9k_hw_enable_interrupts 825
> > > > >> [ 83.269919] ath9k_hw_enable_interrupts 832
> > > > >> [ 83.274083] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.278945] AR_SREV_9100 0
> > > > >> [ 83.281630] ath9k_hw_enable_interrupts 848
> > > > >> [ 83.281633] ath9k_hw_intrpend 762
> > > > >> [ 83.281634] (AR_SREV_9340(ah) val 0
> > > > >> [ 83.281637] ath9k_hw_intrpend 767
> > > > >> [ 83.281648] ath_isr 603
> > > > >> [ 83.281649] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.281651] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.281654] ath9k_hw_kill_interrupts 793
> > > > >> [ 83.312192] ath9k: ath9k_ioread32 ffffff800a400024
> > > > >> [ 83.317030] ath9k_hw_enable_interrupts 821
> > > > >> [ 83.321132] ath9k_hw_enable_interrupts 825
> > > > >> [ 83.325297] ath9k_hw_enable_interrupts 832
> > > > >> [ 83.329463] ath9k: ath9k_iowrite32 ffffff800a400024
> > > > >> [ 83.334324] AR_SREV_9100 0
> > > > >> [ 83.337014] ath9k_hw_enable_interrupts 848
> > > > >> ..
> > > > >> ..
> > > > >> This log continues until I turn off board without obtaining scanning
> result.
> > > > >>
> > > > >> In between I get following cpu stall outputs :
> > > > >> 230.457179] INFO: rcu_sched self-detected stall on CPU
> > > > >> [ 230.457185] 2-...: (31314 ticks this GP)
> > > > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=36713
> > > > >> [ 230.457189] (t=36756 jiffies g=161 c=160 q=16169)
> > > > >> [ 230.457191] Task dump for CPU 2:
> > > > >> [ 230.457196] kworker/u8:4 R running task 0 1342 2
> > 0x00000002
> > > > >> [ 230.457207] Workqueue: phy0 ieee80211_scan_work [
> > > > >> 230.457208] Call trace:
> > > > >> [ 230.457214] [<ffffff8008089860>] dump_backtrace+0x0/0x198 [
> > > > >> 230.457219] [<ffffff8008089a0c>] show_stack+0x14/0x20 [
> > > > >> 230.457224] [<ffffff80080c0930>] sched_show_task+0x98/0xf8 [
> > > > >> 230.457228] [<ffffff80080c2628>] dump_cpu_task+0x40/0x50 [
> > > > >> 230.457233] [<ffffff80080e14a8>] rcu_dump_cpu_stacks+0xa0/0xf0
> > > > >> [ 230.457239] [<ffffff80080e4cd8>]
> > > > >> rcu_check_callbacks+0x468/0x748 [ 230.457243]
> > > > >> [<ffffff80080e7cfc>]
> > > > >> update_process_times+0x3c/0x68 [ 230.457249]
> > > > >> [<ffffff80080f6dfc>] tick_sched_handle.isra.5+0x3c/0x50
> > > > >> [ 230.457253] [<ffffff80080f6e54>] tick_sched_timer+0x44/0x90
> > > > >> [ 230.457257] [<ffffff80080e86b0>]
> > > > >> __hrtimer_run_queues+0xf0/0x178
> > > > >> ** 10 printk messages dropped ** [ 230.457302] f8c0:
> > > > >> 0000000000000000 0000000005f5e0ff 000000000001379a
> > > > 3866666666666620 [
> > > > >> 230.457306] f8e0: ffffff800a1b4065 0000000000000006
> > > > >> ffffff800a129000
> > > > >> ffffffc87b8010a8 [ 230.457310] f900: ffffff808a1b4057
> > > > >> ffffff800a1c3000 ffffff800a1b3000 ffffff800a13b000 [
> > > > >> 230.457314]
> > > > >> f920: 0000000000000140 0000000000000006 ffffff800a1b3b10
> > > > >> ffffff800a1c39e8 [ 230.457318] f940: 000000000000002f
> > > > >> ffffff800a1b8a98 ffffff800a1b3ae8 ffffffc87b07f990 [
> > > > >> 230.457322]
> > > > >> f960: ffffff80080d6230 ffffffc87b07f990 ffffff80080d6234
> > > > >> 0000000060000145
> > > > >> ** 1 printk messages dropped ** [ 230.457329]
> > > > >> [<ffffff8008085720>]
> > > > >> el1_irq+0xa0/0x100
> > > > >> ** 9 printk messages dropped ** [ 230.457373]
> > > > >> [<ffffff800885ad60>]
> > > > >> ieee80211_hw_config+0x50/0x290 [ 230.457377]
> > > > >> [<ffffff8008863690>]
> > > > >> ieee80211_scan_work+0x1f8/0x480 [ 230.457383]
> > > > >> [<ffffff80080b15d0>]
> > > > >> process_one_work+0x120/0x378 [ 230.457386]
> > > > >> [<ffffff80080b1870>]
> > > > >> worker_thread+0x48/0x4b0 [ 230.457391] [<ffffff80080b7108>]
> > > > >> kthread+0xd0/0xe8 [ 230.457395] [<ffffff8008085dd0>]
> > > > ret_from_fork+0x10/0x40
> > > > >> [ 230.480389] ath9k_hw_intrpend 762
> > > > >>
> > > > >>
> > > > >> [ 545.487987] ath9k: ath9k_ioread32 ffffff800a400024 [
> > > > >> 545.526189]
> > > > >> INFO: rcu_sched self-detected stall on CPU
> > > > >> [ 545.526195] 2-...: (97636 ticks this GP)
> > > > idle=2d1/140000000000001/0 softirq=1400/1400 fqs=115374
> > > > >> [ 545.526199] (t=115523 jiffies g=161 c=160 q=51066)
> > > > >> [ 545.526201] Task dump for CPU 2:
> > > > >> [ 545.526206] kworker/u8:4 R running task 0 1342 2
> > 0x00000002
> > > > >> ** 3 printk messages dropped ** [ 545.526231]
> > > > >> [<ffffff8008089a0c>]
> > > > >> show_stack+0x14/0x20
> > > > >> ** 9 printk messages dropped ** [ 545.526280]
> > > > >> [<ffffff80086a71e8>]
> > > > >> arch_timer_handler_phys+0x30/0x40 [ 545.526284]
> > > > >> [<ffffff80080dbe18>]
> > > > >> handle_percpu_devid_irq+0x78/0xa0 [ 545.526291]
> > > > >> [<ffffff80080d760c>]
> > > > >> generic_handle_irq+0x24/0x38 [ 545.526296]
> > > > >> [<ffffff80080d7944>]
> > > > >> __handle_domain_irq+0x5c/0xb8 [ 545.526299]
> > > > >> [<ffffff80080824bc>]
> > > > >> gic_handle_irq+0x64/0xc0 [ 545.526302] Exception
> > > > >> stack(0xffffffc87b07f870
> > > > to 0xffffffc87b07f990)
> > > > >> [ 545.526306] f860: 0000000000009732
> > ffffff800a1eaaa8
> > > > >> ** 8 printk messages dropped ** [ 545.526341] f980:
> > > > >> ffffff800a1c39e8
> > > > >> 0000000000000036 [ 545.526345] [<ffffff8008085720>]
> > > > >> el1_irq+0xa0/0x100 [ 545.526349] [<ffffff80080d6234>]
> > > > >> console_unlock+0x384/0x5b0 [ 545.526353] [<ffffff80080d673c>]
> > > > >> vprintk_emit+0x2dc/0x4b0 [ 545.526357] [<ffffff80080d6a50>]
> > > > >> vprintk_default+0x38/0x40 [ 545.526362] [<ffffff8008129704>]
> > > > >> printk+0x58/0x60 [ 545.526366] [<ffffff800859e3e4>]
> > > > >> ath9k_iowrite32+0x9c/0xa8 [ 545.526372] [<ffffff80085c7ca8>]
> > > > >> ath9k_hw_kill_interrupts+0x28/0xf0
> > > > >> [ 545.526376] [<ffffff80085a18ec>] ath_reset+0x24/0x68
> > > > >> ** 2 printk messages dropped ** [ 545.526391]
> > > > >> [<ffffff800885ad60>]
> > > > ieee80211_hw_config+0x50/0x290
> > > > >> ** 11 printk messages dropped ** [ 545.532834]
> > > > >> ath9k_hw_kill_interrupts
> > > > 793
> > > > >> [ 545.532890] ath9k_hw_enable_interrupts 821
> > > >
> > > > [ 81.876902] INFO: rcu_preempt detected stalls on CPUs/tasks:
> > > > [ 81.876912] Tasks blocked on level-0 rcu_node (CPUs 0-7): P0
> > > > [ 81.876932] (detected by 4, t=60002 jiffies, g=1873, c=1872, q=4967)
> > > > [ 81.876936] swapper/4 R running task 0 0 1
> > > > 0x00000000
> > > > [ 81.876941] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > > > ffffffff81a3dc40
> > > > [ 81.876945] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > > > ffffffff81a3dc40
> > > > [ 81.876948] 00000000ffffffff ffffffff810a7333 ffff88017ecee698
> > > > ffff88017edbc240
> > > > [ 81.876951] Call Trace:
> > > > [ 81.876970] <IRQ>
> > > > [ 81.876979] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > > > [ 81.876983] [<ffffffff81101e46>] ?
> > > > rcu_print_detail_task_stall_rnp+0x40/0x61
> > > > [ 81.876989] [<ffffffff810a7333>] ? rcu_check_callbacks+0x6b3/0x8c0
> > > > [ 81.876993] [<ffffffff810b8350>] ?
> tick_sched_handle.isra.14+0x40/0x40
> > > > [ 81.876996] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > > > [ 81.876999] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > > > [ 81.877002] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > > > [ 81.877004] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > > > [ 81.877008] [<ffffffff81031b1e>] ?
> > > > smp_trace_apic_timer_interrupt+0x5e/0x90
> > > > [ 81.877012] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > > > [ 81.877013] <EOI>
> > > > [ 81.877017] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > > > [ 81.877019] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > > > [ 81.877021] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > > > [ 81.877027] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > > > [ 81.877029] swapper/4 R running task 0 0 1
> > > > 0x00000000
> > > > [ 81.877032] 0000000000000001 ffffffff810725f6 ffff88017edbc240
> > > > ffffffff81a3dc40
> > > > [ 81.877035] ffffffff81101e46 ffff88025ef173c0 ffffffff81a3dc40
> > > > ffffffff81a3dc40
> > > > [ 81.877038] 00000000ffffffff ffffffff810a7368 ffff88017ecee698
> > > > ffff88017edbc240
> > > > [ 81.877041] Call Trace:
> > > > [ 81.877045] <IRQ>
> > > > [ 81.877049] [<ffffffff810725f6>] ? sched_show_task+0xd6/0x140
> > > > [ 81.877051] [<ffffffff81101e46>] ?
> > > > rcu_print_detail_task_stall_rnp+0x40/0x61
> > > > [ 81.877055] [<ffffffff810a7368>] ? rcu_check_callbacks+0x6e8/0x8c0
> > > > [ 81.877058] [<ffffffff810b8350>] ?
> tick_sched_handle.isra.14+0x40/0x40
> > > > [ 81.877060] [<ffffffff810aa4c3>] ? update_process_times+0x23/0x50
> > > > [ 81.877063] [<ffffffff810b8383>] ? tick_sched_timer+0x33/0x60
> > > > [ 81.877065] [<ffffffff810aaf09>] ? __hrtimer_run_queues+0xb9/0x150
> > > > [ 81.877068] [<ffffffff810ab198>] ? hrtimer_interrupt+0x98/0x1a0
> > > > [ 81.877070] [<ffffffff81031b1e>] ?
> > > > smp_trace_apic_timer_interrupt+0x5e/0x90
> > > > [ 81.877073] [<ffffffff815b31bf>] ? apic_timer_interrupt+0x7f/0x90
> > > > [ 81.877074] <EOI>
> > > > [ 81.877076] [<ffffffff8147f28d>] ? cpuidle_enter_state+0x13d/0x1f0
> > > > [ 81.877078] [<ffffffff8147f289>] ? cpuidle_enter_state+0x139/0x1f0
> > > > [ 81.877080] [<ffffffff81088c19>] ? cpu_startup_entry+0x139/0x210
> > > > [ 81.877084] [<ffffffff8102fc9e>] ? start_secondary+0x13e/0x170
> > > > [ 91.132787] INFO: rcu_preempt detected expedited stalls on
> > > > CPUs/tasks: { P0 } 63785 jiffies s: 505 root: 0x0/T
> > > > [ 91.132796] blocking rcu_node structures:
> > > >
> > > > >>
> > > > >>
> > > > >> But if we have less debug prints it does not reach EP handler
> > > > >> sometimes, due to following Condition in "kernel/irq/chip.c" in
> > > > >> function handle_simple_irq
> > > > >>
> > > > >> if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
> > > > >> desc->istate |= IRQS_PENDING;
> > > > >> goto out_unlock;
> > > > >> }
> > > > >> Here irqd_irq_disabled is being set to 1.
> > > > >>
> > > > >> With lesser debug prints it stops after following prints:
> > > > >> root@Xilinx-ZCU102-2016_3:~# iw dev wlan0 scan
> > > > >> [ 54.781045] ath9k_hw_kill_interrupts 793
> > > > >> [ 54.785007] ath9k_hw_kill_interrupts 793
> > > > >> [ 54.792535] ath9k_hw_enable_interrupts 821
> > > > >> [ 54.796642] ath9k_hw_enable_interrupts 825
> > > > >> [ 54.800807] ath9k_hw_enable_interrupts 832
> > > > >> [ 54.804973] AR_SREV_9100 0
> > > > >> [ 54.807663] ath9k_hw_enable_interrupts 848
> > > > >> [ 54.811843] ath9k_hw_intrpend 762
> > > > >> [ 54.815211] (AR_SREV_9340(ah) val 0
> > > > >> [ 54.818684] ath9k_hw_intrpend 767
> > > > >> [ 54.822078] ath_isr 603
> > > > >> [ 54.824587] ath9k_hw_kill_interrupts 793
> > > > >> [ 54.828601] ath9k_hw_enable_interrupts 821
> > > > >> [ 54.832750] ath9k_hw_enable_interrupts 825
> > > > >> [ 54.836916] ath9k_hw_enable_interrupts 832
> > > > >> [ 54.841082] AR_SREV_9100 0
> > > > >> [ 54.843772] ath9k_hw_enable_interrupts 848
> > > > >> [ 54.843775] ath9k_hw_intrpend 762
> > > > >> [ 54.851319] (AR_SREV_9340(ah) val 0
> > > > >> [ 54.854793] ath9k_hw_intrpend 767
> > > > >> [ 54.858185] ath_isr 603
> > > > >> [ 54.860696] ath9k_hw_kill_interrupts 793
> > > > >> [ 54.864776] ath9k_hw_enable_interrupts 821
> > > > >> [ 54.867061] ath9k_hw_kill_interrupts 793
> > > > >> [ 54.872870] ath9k_hw_enable_interrupts 825
> > > > >> [ 54.877036] ath9k_hw_enable_interrupts 832
> > > > >> [ 54.881202] AR_SREV_9100 0
> > > > >> [ 54.883892] ath9k_hw_enable_interrupts 848
> > > > >> [ 75.963129] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > > >> [ 75.968602] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > > > softirq=1103/1109 fqs=519
> > > > >> [ 75.976675] (detected by 2, t=5274 jiffies, g=64, c=63, q=11)
> > > > >> [ 75.982485] Task dump for CPU 0:
> > > > >> [ 75.985696] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > > >> [ 75.992726] Call trace:
> > > > >> [ 75.995165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0
> > > > >> [ 76.000281] [<ffffffc87b830500>] 0xffffffc87b830500
> > > > >> [ 139.059027] INFO: rcu_sched detected stalls on CPUs/tasks:
> > > > >> [ 139.064430] 0-...: (2 GPs behind) idle=9d5/140000000000001/0
> > > > softirq=1103/1109 fqs=2097
> > > > >> [ 139.072593] (detected by 2, t=21049 jiffies, g=64, c=63, q=11)
> > > > >> [ 139.078489] Task dump for CPU 0:
> > > > >> [ 139.081700] ksoftirqd/0 R running task 0 3 2 0x00000002
> > > > >> [ 139.088731] Call trace:
> > > > >> [ 139.091165] [<ffffff8008086b3c>] __switch_to+0xc4/0xd0 [
> > > > >> 139.096285] [<ffffffc87b830500>] 0xffffffc87b830500
> > > > >>
> > > > >>
> > > > >>>> We are not seeing any issues on 32-bit ARM platform and X86
> > > > >>>> platform.
> > > > >>> Can you collect a dmesg log (or, if the system hang means you
> > > > >>> can't collect that, a console log with "ignore_loglevel"), and "lspci -vv"
> > > > >>> output as root? That should have clues about whether the INTx
> > > > >>> got routed correctly. /proc/interrupts should also show
> > > > >>> whether we're receiving interrupts from the device.
> > > > >> Here is the lspci output:
> > > > >> 00:00.0 PCI bridge: Xilinx Corporation Device d022 (prog-if 00
> > > > >> [Normal
> > > > decode])
> > > > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV-
> VGASnoop-
> > > > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast
> >TAbort-
> > > > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > > >> Latency: 0
> > > > >> Interrupt: pin A routed to IRQ 224
> > > > >> Bus: primary=00, secondary=01, subordinate=0c, sec-latency=0
> > > > >> I/O behind bridge: 00000000-00000fff
> > > > >> Memory behind bridge: e0000000-e00fffff
> > > > >> Prefetchable memory behind bridge: 00000000fff00000-
> > > > 00000000000fffff
> > > > >> Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast
> >TAbort-
> > > > <TAbort- <MAbort- <SERR- <PERR-
> > > > >> BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
> > > > >> PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
> > > > >> Capabilities: [40] Power Management version 3
> > > > >> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> > > > PME(D0+,D1+,D2+,D3hot+,D3cold-)
> > > > >> Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0
> PME-
> > > > >> Capabilities: [60] Express (v2) Root Port (Slot-), MSI 00
> > > > >> DevCap: MaxPayload 256 bytes, PhantFunc 0
> > > > >> ExtTag- RBE+
> > > > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > > > Unsupported-
> > > > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr-
> NoSnoop+
> > > > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq-
> AuxPwr-
> > > > TransPend+
> > > > >> LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM not
> supported,
> > > > Exit Latency L0s unlimited, L1 unlimited
> > > > >> ClockPM- Surprise- LLActRep- BwNot+
> ASPMOptComp+
> > > > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled-
> CommClk-
> > > > >> ExtSynch- ClockPM- AutWidDis- BWInt-
> AutBWInt-
> > > > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > > > DLActive- BWMgmt- ABWMgmt-
> > > > >> RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal-
> PMEIntEna-
> > > > CRSVisible+
> > > > >> RootCap: CRSVisible+
> > > > >> RootSta: PME ReqID 0000, PMEStatus- PMEPending-
> > > > >> DevCap2: Completion Timeout: Range B, TimeoutDis+,
> LTR-,
> > > > OBFF Not Supported ARIFwd-
> > > > >> DevCtl2: Completion Timeout: 50us to 50ms,
> TimeoutDis-, LTR-,
> > > > OBFF Disabled ARIFwd-
> > > > >> LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance-
> SpeedDis-
> > > > >> Transmit Margin: Normal Operating Range,
> > > > EnterModifiedCompliance- ComplianceSOS-
> > > > >> Compliance De-emphasis: -6dB
> > > > >> LnkSta2: Current De-emphasis Level: -3.5dB,
> > > > EqualizationComplete-, EqualizationPhase1-
> > > > >> EqualizationPhase2-, EqualizationPhase3-,
> > > > LinkEqualizationRequest-
> > > > >> Capabilities: [100 v1] Device Serial Number 00-00-00-00-00-00-
> 00-00
> > > > >> Capabilities: [10c v1] Virtual Channel
> > > > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > > > >> Ctrl: ArbSelect=Fixed
> > > > >> Status: InProgress-
> > > > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1
> RejSnoopTrans-
> > > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> TWRR128-
> > > > WRR256-
> > > > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > > >> Status: NegoPending- InProgress-
> > > > >> Capabilities: [128 v1] Vendor Specific Information: ID=1234
> > > > >> Rev=1
> > > > >> Len=018 <?>
> > > > >>
> > > > >> 01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless
> > > > >> Network
> > > > Adapter (rev 01)
> > > > >> Subsystem: Qualcomm Atheros Device 3112
> > > > >> Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV-
> VGASnoop-
> > > > ParErr- Stepping- SERR- FastB2B- DisINTx-
> > > > >> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast
> >TAbort-
> > > > <TAbort- <MAbort- >SERR- <PERR- INTx-
> > > > >> Latency: 0, Cache Line Size: 128 bytes
> > > > >> Interrupt: pin A routed to IRQ 224
> > > > >> Region 0: Memory at e0000000 (64-bit, non-prefetchable)
> [size=128K]
> > > > >> [virtual] Expansion ROM at e0020000 [disabled] [size=64K]
> > > > >> Capabilities: [40] Power Management version 3
> > > > >> Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA
> > > > PME(D0+,D1+,D2-,D3hot+,D3cold-)
> > > > >> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0
> PME-
> > > > >> Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
> > > > >> Address: 0000000000000000 Data: 0000
> > > > >> Masking: 00000000 Pending: 00000000
> > > > >> Capabilities: [70] Express (v2) Endpoint, MSI 00
> > > > >> DevCap: MaxPayload 128 bytes, PhantFunc 0,
> Latency
> > > > L0s <1us, L1 <8us
> > > > >> ExtTag- AttnBtn- AttnInd- PwrInd- RBE+
> FLReset-
> > > > SlotPowerLimit 0.000W
> > > > >> DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> > > > Unsupported-
> > > > >> RlxdOrd+ ExtTag- PhantFunc- AuxPwr-
> NoSnoop-
> > > > >> MaxPayload 128 bytes, MaxReadReq 512 bytes
> > > > >> DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq-
> AuxPwr-
> > > > TransPend-
> > > > >> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1,
> Exit
> > > > Latency L0s <2us, L1 <64us
> > > > >> ClockPM- Surprise- LLActRep- BwNot-
> ASPMOptComp-
> > > > >> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled-
> CommClk-
> > > > >> ExtSynch- ClockPM- AutWidDis- BWInt-
> AutBWInt-
> > > > >> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+
> > > > DLActive- BWMgmt- ABWMgmt-
> > > > >> DevCap2: Completion Timeout: Not Supported,
> TimeoutDis+,
> > > > LTR-, OBFF Not Supported
> > > > >> DevCtl2: Completion Timeout: 50us to 50ms,
> TimeoutDis-, LTR-,
> > > > OBFF Disabled
> > > > >> LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance-
> > > > SpeedDis-
> > > > >> Transmit Margin: Normal Operating Range,
> > > > EnterModifiedCompliance- ComplianceSOS-
> > > > >> Compliance De-emphasis: -6dB
> > > > >> LnkSta2: Current De-emphasis Level: -6dB,
> > > > EqualizationComplete-, EqualizationPhase1-
> > > > >> EqualizationPhase2-, EqualizationPhase3-,
> > > > LinkEqualizationRequest-
> > > > >> Capabilities: [100 v1] Advanced Error Reporting
> > > > >> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt-
> UnxCmplt-
> > > > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > > >> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt-
> UnxCmplt-
> > > > RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> > > > >> UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt-
> UnxCmplt-
> > > > RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> > > > >> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > > > NonFatalErr-
> > > > >> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout-
> > > > NonFatalErr+
> > > > >> AERCap: First Error Pointer: 00, GenCap-
> CGenEn-
> > > > ChkCap- ChkEn-
> > > > >> Capabilities: [140 v1] Virtual Channel
> > > > >> Caps: LPEVC=0 RefClk=100ns PATEntryBits=1
> > > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> > > > >> Ctrl: ArbSelect=Fixed
> > > > >> Status: InProgress-
> > > > >> VC0: Caps: PATOffset=00 MaxTimeSlots=1
> RejSnoopTrans-
> > > > >> Arb: Fixed- WRR32- WRR64- WRR128-
> TWRR128-
> > > > WRR256-
> > > > >> Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
> > > > >> Status: NegoPending- InProgress-
> > > > >> Capabilities: [300 v1] Device Serial Number 00-00-00-00-00-00-
> 00-00
> > > > >> Kernel driver in use: ath9k
> > > > >>
> > > > >> Here is the cat /proc/interrupts (after we do interface up):
> > > > >>
> > > > >> root@:~# ifconfig wlan0 up
> > > > >> [ 1548.926601] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not
> > > > >> ready root@Xilinx-ZCU102-2016_3:~# cat /proc/interrupts
> > > > >> CPU0 CPU1 CPU2 CPU3
> > > > >> 1: 0 0 0 0 GICv2 29 Edge arch_timer
> > > > >> 2: 19873 20058 19089 17435 GICv2 30 Edge
> arch_timer
> > > > >> 12: 0 0 0 0 GICv2 156 Level zynqmp-dma
> > > > >> 13: 0 0 0 0 GICv2 157 Level zynqmp-dma
> > > > >> 14: 0 0 0 0 GICv2 158 Level zynqmp-dma
> > > > >> 15: 0 0 0 0 GICv2 159 Level zynqmp-dma
> > > > >> 16: 0 0 0 0 GICv2 160 Level zynqmp-dma
> > > > >> 17: 0 0 0 0 GICv2 161 Level zynqmp-dma
> > > > >> 18: 0 0 0 0 GICv2 162 Level zynqmp-dma
> > > > >> 19: 0 0 0 0 GICv2 163 Level zynqmp-dma
> > > > >> 20: 0 0 0 0 GICv2 164 Level Mali_GP_MMU,
> > > > Mali_GP, Mali_PP0_MMU, Mali_PP0, Mali_PP1_MMU, Mali_PP1
> > > > >> 30: 0 0 0 0 GICv2 95 Level eth0, eth0
> > > > >> 206: 314 0 0 0 GICv2 49 Level cdns-i2c
> > > > >> 207: 40 0 0 0 GICv2 50 Level cdns-i2c
> > > > >> 209: 0 0 0 0 GICv2 150 Level nwl_pcie:misc
> > > > >> 214: 12 0 0 0 GICv2 47 Level ff0f0000.spi
> > > > >> 215: 0 0 0 0 GICv2 58 Level ffa60000.rtc
> > > > >> 216: 0 0 0 0 GICv2 59 Level ffa60000.rtc
> > > > >> 217: 0 0 0 0 GICv2 165 Level ahci-
> > > > ceva[fd0c0000.ahci]
> > > > >> 218: 61 0 0 0 GICv2 81 Level mmc0
> > > > >> 219: 0 0 0 0 GICv2 187 Level arm-smmu global
> > fault
> > > > >> 220: 471 0 0 0 GICv2 53 Level xuartps
> > > > >> 223: 0 0 0 0 GICv2 154 Level fd4c0000.dma
> > > > >> 224: 3 0 0 0 dummy 1 Edge ath9k
> > > > >> 225: 0 0 0 0 GICv2 97 Level xhci-hcd:usb1
> > > > >>
> > > > >> Regards,
> > > > >> Bharat
> > >
> --
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