Hi,
There seems to be a regression in the upcoming Linux 3.16-rc2 release
candidate that I bisected down to this first bad commit:
[dbb42748ac4929987c1449ecb296b39ef8956b62] drm/i915: Move the C3 LP
write bit setup to gen3_init_clock_gating() for KMS.
The regression is that during the Ubuntu boot process, the monitor
becomes blank and displays "no signal, going to sleep". This happens
around Kernel Mode Setting time, and does not occur with the
"nomodeset" kernel parameter.
The machine under test is a HP-branded single core Intel Pentium 4 CPU
@ 3.00GHz with this GPU:
00:02.0 VGA compatible controller: Intel Corporation 82945G/GZ
Integrated Graphics Controller (rev 02) (prog-if 00 [VGA controller])
Subsystem: Hewlett-Packard Company Device 3012
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 16
Region 0: Memory at e0400000 (32-bit, non-prefetchable) [size=512K]
Region 1: I/O ports at 10c0 [size=8]
Region 2: Memory at d0000000 (32-bit, prefetchable) [size=256M]
Region 3: Memory at e0480000 (32-bit, non-prefetchable) [size=256K]
Expansion ROM at <unassigned> [disabled]
Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
Address: 00000000 Data: 0000
Capabilities: [d0] Power Management version 2
Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA
PME(D0-,D1-,D2-,D3hot-,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
Kernel driver in use: i915
I confirmed that this regression still exists with the latest version
of Linus' tree.
Kind regards and thanks for all your hard work!
Tom Van Braeckel.
On Wed, Jun 25, 2014 at 03:03:44PM +0200, Tom Van Braeckel wrote:
> Hi,
>
> There seems to be a regression in the upcoming Linux 3.16-rc2 release
> candidate that I bisected down to this first bad commit:
> [dbb42748ac4929987c1449ecb296b39ef8956b62] drm/i915: Move the C3 LP
> write bit setup to gen3_init_clock_gating() for KMS.
Can you attach the dmesg with rc2 and dbb4274 reverted?
-Chris
--
Chris Wilson, Intel Open Source Technology Centre
>> There seems to be a regression in the upcoming Linux 3.16-rc2 release
>> candidate that I bisected down to this first bad commit:
>> [dbb42748ac4929987c1449ecb296b39ef8956b62] drm/i915: Move the C3 LP
>> write bit setup to gen3_init_clock_gating() for KMS.
>
> Can you attach the dmesg with rc2 and dbb4274 reverted?
Hmm, for some reason I started having a hard time reproducing the
issue on commit dbb4274.
I still have it on the 3.16-rc2 though and I'm doing another bisect.
The issue comes and goes during the bisect so let's see where it
leads... perhaps it turns out to be some configuration setting.