2013-10-29 17:54:23

by David Cohen

[permalink] [raw]
Subject: [RFC/PATCH 0/2] mmc: sdhci: Workaround Intel Merrifield issue for HS200

Hi,

SDHCI used to work well on Intel Merrifield until this patch was applied:

commit 156e14b126ffb6f040bc6f1aff3c51077e42a744
Author: Giuseppe CAVALLARO <[email protected]>
Date: Wed Jun 12 08:16:38 2013 +0200

mmc: sdhci: fix caps2 for HS200

Although the HC supports HS200 (eMMC) the caps2 are always zero; this
means there's no way to use the super speed mode (when init the card).

If the HC support SDR104, for SD3.0, so it also supports HS200 for eMMC
and this patch just sets the MMC_CAP2_HS200 in the host caps2 field.

Looks like there is a hw issue with unknown root cause so far.

Is it acceptable to have the quirk I'm proposing to workaround the issue?

Br, David Cohen

---
David Cohen (2):
mmc: sdhci: add quirk for broken HS200 support
mmc: sdhci-pci: add broken HS200 quirk for Intel Merrifield

drivers/mmc/host/sdhci-pci.c | 1 +
drivers/mmc/host/sdhci.c | 3 ++-
include/linux/mmc/sdhci.h | 2 ++
3 files changed, 5 insertions(+), 1 deletion(-)

--
1.8.4.rc3


2013-10-29 17:54:24

by David Cohen

[permalink] [raw]
Subject: [RFC/PATCH 1/2] mmc: sdhci: add quirk for broken HS200 support

This patch defines a quirk for platforms unable to enable HS200 support.

Signed-off-by: David Cohen <[email protected]>
Reviewed-by: Chuanxiao Dong <[email protected]>
---
drivers/mmc/host/sdhci.c | 3 ++-
include/linux/mmc/sdhci.h | 2 ++
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7a7fb4f..ef91ad4 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3002,7 +3002,8 @@ int sdhci_add_host(struct sdhci_host *host)
/* SD3.0: SDR104 is supported so (for eMMC) the caps2
* field can be promoted to support HS200.
*/
- mmc->caps2 |= MMC_CAP2_HS200;
+ if (!(host->quirks2 & SDHCI_QUIRK2_BROKEN_HS200))
+ mmc->caps2 |= MMC_CAP2_HS200;
} else if (caps[1] & SDHCI_SUPPORT_SDR50)
mmc->caps |= MMC_CAP_UHS_SDR50;

diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 3e781b8..362927c4 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -98,6 +98,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON (1<<4)
/* Controller has a non-standard host control register */
#define SDHCI_QUIRK2_BROKEN_HOST_CONTROL (1<<5)
+/* Controller does not support HS200 */
+#define SDHCI_QUIRK2_BROKEN_HS200 (1<<6)

int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.8.4.rc3

2013-10-29 17:54:48

by David Cohen

[permalink] [raw]
Subject: [RFC/PATCH 2/2] mmc: sdhci-pci: add broken HS200 quirk for Intel Merrifield

Due to unkown hw issue so far, Merrifield is unable to enable HS200
support. This patch adds quirk to avoid SDHCI to initialize with error
below:

[ 53.850132] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W
3.12.0-rc6-00037-g3d7c8d9-dirty #36
[ 53.850150] Hardware name: Intel Corporation Merrifield/SALT BAY,
BIOS 397 2013.09.12:11.51.40
[ 53.850167] 00000000 00000000 ee409e48 c18816d2 00000000 ee409e78
c123e254 c1acc9b0
[ 53.850227] 00000000 00000000 c1b14148 000003de c16c03bf c16c03bf
ee75b480 ed97c54c
[ 53.850282] ee75b480 ee409e88 c123e292 00000009 00000000 ee409ef8
c16c03bf c1207fac
[ 53.850339] Call Trace:
[ 53.850376] [<c18816d2>] dump_stack+0x4b/0x79
[ 53.850408] [<c123e254>] warn_slowpath_common+0x84/0xa0
[ 53.850436] [<c16c03bf>] ? sdhci_send_command+0xb4f/0xc50
[ 53.850462] [<c16c03bf>] ? sdhci_send_command+0xb4f/0xc50
[ 53.850490] [<c123e292>] warn_slowpath_null+0x22/0x30
[ 53.850516] [<c16c03bf>] sdhci_send_command+0xb4f/0xc50
[ 53.850545] [<c1207fac>] ? native_sched_clock+0x2c/0xb0
[ 53.850575] [<c14c1f93>] ? delay_tsc+0x73/0xb0
[ 53.850601] [<c14c1ebe>] ? __const_udelay+0x1e/0x20
[ 53.850626] [<c16bdeb3>] ? sdhci_reset+0x93/0x190
[ 53.850654] [<c16c05b0>] sdhci_finish_data+0xf0/0x2e0
[ 53.850683] [<c16c130f>] sdhci_irq+0x31f/0x930
[ 53.850713] [<c12cb080>] ? __buffer_unlock_commit+0x10/0x20
[ 53.850740] [<c12cbcd7>] ? trace_buffer_unlock_commit+0x37/0x50
[ 53.850773] [<c1288f3c>] handle_irq_event_percpu+0x5c/0x220
[ 53.850800] [<c128bc96>] ? handle_fasteoi_irq+0x16/0xd0
[ 53.850827] [<c128913a>] handle_irq_event+0x3a/0x60
[ 53.850852] [<c128bc80>] ? unmask_irq+0x30/0x30
[ 53.850878] [<c128bcce>] handle_fasteoi_irq+0x4e/0xd0
[ 53.850895] <IRQ> [<c1890b52>] ? do_IRQ+0x42/0xb0
[ 53.850943] [<c1890a31>] ? common_interrupt+0x31/0x38
[ 53.850973] [<c12b00d8>] ? cgroup_mkdir+0x4e8/0x580
[ 53.851001] [<c1208d32>] ? default_idle+0x22/0xf0
[ 53.851029] [<c1209576>] ? arch_cpu_idle+0x26/0x30
[ 53.851054] [<c1288505>] ? cpu_startup_entry+0x65/0x240
[ 53.851082] [<c18793d5>] ? rest_init+0xb5/0xc0
[ 53.851108] [<c1879320>] ? __read_lock_failed+0x18/0x18
[ 53.851138] [<c1bf6a15>] ? start_kernel+0x31b/0x321
[ 53.851164] [<c1bf652f>] ? repair_env_string+0x51/0x51
[ 53.851190] [<c1bf6363>] ? i386_start_kernel+0x139/0x13c
[ 53.851209] ---[ end trace 92777f5fe48d33f2 ]---
[ 53.853449] mmcblk0: error -84 transferring data, sector 11142162, nr
304, cmd response 0x0, card status 0x0
[ 53.853476] mmcblk0: retrying using single block read
[ 55.937863] sdhci: Timeout waiting for Buffer Read Ready interrupt
during tuning procedure, falling back to fixed sampling clock
[ 56.207951] sdhci: Timeout waiting for Buffer Read Ready interrupt
during tuning procedure, falling back to fixed sampling clock
[ 66.228785] mmc0: Timeout waiting for hardware interrupt.
[ 66.230855] ------------[ cut here ]------------

Signed-off-by: David Cohen <[email protected]>
Reviewed-by: Chuanxiao Dong <[email protected]>
---
drivers/mmc/host/sdhci-pci.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 06f026a..86a7fbb 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -376,6 +376,7 @@ static int intel_mrfl_mmc_probe_slot(struct sdhci_pci_slot *slot)

static const struct sdhci_pci_fixes sdhci_intel_mrfl_mmc = {
.quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
+ .quirks2 = SDHCI_QUIRK2_BROKEN_HS200,
.probe_slot = intel_mrfl_mmc_probe_slot,
};

--
1.8.4.rc3

2014-01-13 17:55:25

by Chris Ball

[permalink] [raw]
Subject: Re: [RFC/PATCH 0/2] mmc: sdhci: Workaround Intel Merrifield issue for HS200

Hi David, Dong,

On Fri, Dec 20 2013, Dong Aisheng wrote:
> On Fri, Dec 20, 2013 at 11:25 AM, David Cohen
> <[email protected]> wrote:
>> Merrifield still needs this quirk to not break MMC support.
>> This quirk could be applied to 3.13-rc (since merrifield was added to
>> sdhci-pci.c on 3.13-rc1).
>
> Okay, thanks for the information.
> So please take my ACK:
> Acked-by: Dong Aisheng <[email protected]>

Thanks, I've pushed this to mmc-next now.

- Chris.
--
Chris Ball <[email protected]> <http://printf.net/>