2019-07-15 11:00:52

by Baolin Wang

[permalink] [raw]
Subject: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming

In sdhci_runtime_resume_host() function, we will always do software reset
for all, but according to the specification, we should issue reset command
and reinitialize the SD/eMMC card. However, we only do reinitialize the
SD/eMMC card when the SD/eMMC card are power down during runtime suspend.

Thus for those platforms that do not power down the SD/eMMC card during
runtime suspend, we should not do software reset for all. To fix this
issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
to decide if we can do software reset for all or just reset command
and data lines.

Signed-off-by: Baolin Wang <[email protected]>
---
drivers/mmc/host/sdhci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9715834..470c5e0 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
host->ops->enable_dma(host);
}

- sdhci_init(host, 0);
+ sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));

if (mmc->ios.power_mode != MMC_POWER_UNDEFINED &&
mmc->ios.power_mode != MMC_POWER_OFF) {
--
1.7.9.5


2019-07-15 11:22:58

by Adrian Hunter

[permalink] [raw]
Subject: Re: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming

On 15/07/19 1:58 PM, Baolin Wang wrote:
> In sdhci_runtime_resume_host() function, we will always do software reset
> for all, but according to the specification, we should issue reset command
> and reinitialize the SD/eMMC card.

Where does it say that?

> However, we only do reinitialize the
> SD/eMMC card when the SD/eMMC card are power down during runtime suspend.
>
> Thus for those platforms that do not power down the SD/eMMC card during
> runtime suspend, we should not do software reset for all.
> To fix this
> issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
> to decide if we can do software reset for all or just reset command
> and data lines.
>
> Signed-off-by: Baolin Wang <[email protected]>
> ---
> drivers/mmc/host/sdhci.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 9715834..470c5e0 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
> host->ops->enable_dma(host);
> }
>
> - sdhci_init(host, 0);
> + sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));

We have done a full reset for a long time, so it would be surprising to need
to change it.

What problem is it causing?

>
> if (mmc->ios.power_mode != MMC_POWER_UNDEFINED &&
> mmc->ios.power_mode != MMC_POWER_OFF) {
>

2019-07-15 11:38:21

by Baolin Wang

[permalink] [raw]
Subject: Re: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming

Hi Adrian,

On Mon, 15 Jul 2019 at 19:20, Adrian Hunter <[email protected]> wrote:
>
> On 15/07/19 1:58 PM, Baolin Wang wrote:
> > In sdhci_runtime_resume_host() function, we will always do software reset
> > for all, but according to the specification, we should issue reset command
> > and reinitialize the SD/eMMC card.
>
> Where does it say that?

I checked the SD host controller simplified specification Ver4.20, and
in Page 75, Software Reset For All bit, it says "if this bit is set
to1, the host driver should issue reset command and reinitialize the
SD card". (I did not check other versions).

>
> > However, we only do reinitialize the
> > SD/eMMC card when the SD/eMMC card are power down during runtime suspend.
> >
> > Thus for those platforms that do not power down the SD/eMMC card during
> > runtime suspend, we should not do software reset for all.
> > To fix this
> > issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
> > to decide if we can do software reset for all or just reset command
> > and data lines.
> >
> > Signed-off-by: Baolin Wang <[email protected]>
> > ---
> > drivers/mmc/host/sdhci.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > index 9715834..470c5e0 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
> > host->ops->enable_dma(host);
> > }
> >
> > - sdhci_init(host, 0);
> > + sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));
>
> We have done a full reset for a long time, so it would be surprising to need
> to change it.
>
> What problem is it causing?

If we did not power down the SD card during runtime suspend, and we
reset for all when runtime resume, our SD host controller can not work
well, will meet some strange behavior, like:

[ 6.525397] mmc0: Got data interrupt 0x00000002 even though no data
operation was in progress.
[ 6.534189] mmc0: sdhci: ============ SDHCI REGISTER DUMP ===========
[ 6.540797] mmc0: sdhci: Sys addr: 0x00000008 | Version: 0x00000004
[ 6.547413] mmc0: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000000
[ 6.554029] mmc0: sdhci: Argument: 0x03200101 | Trn mode: 0x00000033
[ 6.560645] mmc0: sdhci: Present: 0x01f000f0 | Host ctl: 0x00000030
[ 6.567262] mmc0: sdhci: Power: 0x00000000 | Blk gap: 0x00000000
[ 6.573877] mmc0: sdhci: Wake-up: 0x00000000 | Clock: 0x00000007
[ 6.580493] mmc0: sdhci: Timeout: 0x0000000e | Int stat: 0x00000000
[ 6.587109] mmc0: sdhci: Int enab: 0x037f000b | Sig enab: 0x037f000b
[ 6.593726] mmc0: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
[ 6.600342] mmc0: sdhci: Caps: 0x1c6d0080 | Caps_1: 0x08000007
[ 6.606959] mmc0: sdhci: Cmd: 0x0000061b | Max curr: 0x00ffffff
[ 6.613574] mmc0: sdhci: Resp[0]: 0x00001201 | Resp[1]: 0x00000000
[ 6.620190] mmc0: sdhci: Resp[2]: 0x00000000 | Resp[3]: 0x00000000
[ 6.626806] mmc0: sdhci: Host ctl2: 0x00003807
[ 6.631364] mmc0: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x00000000df062000
[ 6.638697] mmc0: sdhci: ============================================
[ 6.645379] mmc0: cache flush error -84

Got data interrupt but no data commands are processing now. With this
patch, then our SD host controller can work well. Did I miss anything
else? Thanks.

--
Baolin Wang
Best Regards

2019-07-15 12:41:26

by Adrian Hunter

[permalink] [raw]
Subject: Re: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming

On 15/07/19 2:37 PM, Baolin Wang wrote:
> Hi Adrian,
>
> On Mon, 15 Jul 2019 at 19:20, Adrian Hunter <[email protected]> wrote:
>>
>> On 15/07/19 1:58 PM, Baolin Wang wrote:
>>> In sdhci_runtime_resume_host() function, we will always do software reset
>>> for all, but according to the specification, we should issue reset command
>>> and reinitialize the SD/eMMC card.
>>
>> Where does it say that?
>
> I checked the SD host controller simplified specification Ver4.20, and
> in Page 75, Software Reset For All bit, it says "if this bit is set
> to1, the host driver should issue reset command and reinitialize the
> SD card". (I did not check other versions).

That might simply be assuming that the bus power also controls the card power.

>
>>
>>> However, we only do reinitialize the
>>> SD/eMMC card when the SD/eMMC card are power down during runtime suspend.
>>>
>>> Thus for those platforms that do not power down the SD/eMMC card during
>>> runtime suspend, we should not do software reset for all.
>>> To fix this
>>> issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
>>> to decide if we can do software reset for all or just reset command
>>> and data lines.
>>>
>>> Signed-off-by: Baolin Wang <[email protected]>
>>> ---
>>> drivers/mmc/host/sdhci.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>>> index 9715834..470c5e0 100644
>>> --- a/drivers/mmc/host/sdhci.c
>>> +++ b/drivers/mmc/host/sdhci.c
>>> @@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
>>> host->ops->enable_dma(host);
>>> }
>>>
>>> - sdhci_init(host, 0);
>>> + sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));
>>
>> We have done a full reset for a long time, so it would be surprising to need
>> to change it.
>>
>> What problem is it causing?
>
> If we did not power down the SD card during runtime suspend, and we
> reset for all when runtime resume, our SD host controller can not work
> well, will meet some strange behavior, like:
>
> [ 6.525397] mmc0: Got data interrupt 0x00000002 even though no data
> operation was in progress.
> [ 6.534189] mmc0: sdhci: ============ SDHCI REGISTER DUMP ===========
> [ 6.540797] mmc0: sdhci: Sys addr: 0x00000008 | Version: 0x00000004
> [ 6.547413] mmc0: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000000
> [ 6.554029] mmc0: sdhci: Argument: 0x03200101 | Trn mode: 0x00000033
> [ 6.560645] mmc0: sdhci: Present: 0x01f000f0 | Host ctl: 0x00000030
> [ 6.567262] mmc0: sdhci: Power: 0x00000000 | Blk gap: 0x00000000
> [ 6.573877] mmc0: sdhci: Wake-up: 0x00000000 | Clock: 0x00000007
> [ 6.580493] mmc0: sdhci: Timeout: 0x0000000e | Int stat: 0x00000000
> [ 6.587109] mmc0: sdhci: Int enab: 0x037f000b | Sig enab: 0x037f000b
> [ 6.593726] mmc0: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
> [ 6.600342] mmc0: sdhci: Caps: 0x1c6d0080 | Caps_1: 0x08000007
> [ 6.606959] mmc0: sdhci: Cmd: 0x0000061b | Max curr: 0x00ffffff
> [ 6.613574] mmc0: sdhci: Resp[0]: 0x00001201 | Resp[1]: 0x00000000
> [ 6.620190] mmc0: sdhci: Resp[2]: 0x00000000 | Resp[3]: 0x00000000
> [ 6.626806] mmc0: sdhci: Host ctl2: 0x00003807
> [ 6.631364] mmc0: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x00000000df062000
> [ 6.638697] mmc0: sdhci: ============================================
> [ 6.645379] mmc0: cache flush error -84
>
> Got data interrupt but no data commands are processing now. With this
> patch, then our SD host controller can work well. Did I miss anything
> else? Thanks.

The response seems to show the card in state 9 bus-testing, which would
suggest the use of CMD19 for eMMC. Perhaps the wrong command is used for
eMMC re-tuning?

The difficulty with changing long standing flow is that it might reveal
problems for other existing hardware. Did you consider making a
driver-specific change? The ->reset() callback could be used.

2019-07-16 05:38:23

by Baolin Wang

[permalink] [raw]
Subject: Re: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming

Hi Adrian,

On Mon, 15 Jul 2019 at 20:39, Adrian Hunter <[email protected]> wrote:
>
> On 15/07/19 2:37 PM, Baolin Wang wrote:
> > Hi Adrian,
> >
> > On Mon, 15 Jul 2019 at 19:20, Adrian Hunter <[email protected]> wrote:
> >>
> >> On 15/07/19 1:58 PM, Baolin Wang wrote:
> >>> In sdhci_runtime_resume_host() function, we will always do software reset
> >>> for all, but according to the specification, we should issue reset command
> >>> and reinitialize the SD/eMMC card.
> >>
> >> Where does it say that?
> >
> > I checked the SD host controller simplified specification Ver4.20, and
> > in Page 75, Software Reset For All bit, it says "if this bit is set
> > to1, the host driver should issue reset command and reinitialize the
> > SD card". (I did not check other versions).
>
> That might simply be assuming that the bus power also controls the card power.

Yes.

>
> >
> >>
> >>> However, we only do reinitialize the
> >>> SD/eMMC card when the SD/eMMC card are power down during runtime suspend.
> >>>
> >>> Thus for those platforms that do not power down the SD/eMMC card during
> >>> runtime suspend, we should not do software reset for all.
> >>> To fix this
> >>> issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
> >>> to decide if we can do software reset for all or just reset command
> >>> and data lines.
> >>>
> >>> Signed-off-by: Baolin Wang <[email protected]>
> >>> ---
> >>> drivers/mmc/host/sdhci.c | 2 +-
> >>> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> >>> index 9715834..470c5e0 100644
> >>> --- a/drivers/mmc/host/sdhci.c
> >>> +++ b/drivers/mmc/host/sdhci.c
> >>> @@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
> >>> host->ops->enable_dma(host);
> >>> }
> >>>
> >>> - sdhci_init(host, 0);
> >>> + sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));
> >>
> >> We have done a full reset for a long time, so it would be surprising to need
> >> to change it.
> >>
> >> What problem is it causing?
> >
> > If we did not power down the SD card during runtime suspend, and we
> > reset for all when runtime resume, our SD host controller can not work
> > well, will meet some strange behavior, like:
> >
> > [ 6.525397] mmc0: Got data interrupt 0x00000002 even though no data
> > operation was in progress.
> > [ 6.534189] mmc0: sdhci: ============ SDHCI REGISTER DUMP ===========
> > [ 6.540797] mmc0: sdhci: Sys addr: 0x00000008 | Version: 0x00000004
> > [ 6.547413] mmc0: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000000
> > [ 6.554029] mmc0: sdhci: Argument: 0x03200101 | Trn mode: 0x00000033
> > [ 6.560645] mmc0: sdhci: Present: 0x01f000f0 | Host ctl: 0x00000030
> > [ 6.567262] mmc0: sdhci: Power: 0x00000000 | Blk gap: 0x00000000
> > [ 6.573877] mmc0: sdhci: Wake-up: 0x00000000 | Clock: 0x00000007
> > [ 6.580493] mmc0: sdhci: Timeout: 0x0000000e | Int stat: 0x00000000
> > [ 6.587109] mmc0: sdhci: Int enab: 0x037f000b | Sig enab: 0x037f000b
> > [ 6.593726] mmc0: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
> > [ 6.600342] mmc0: sdhci: Caps: 0x1c6d0080 | Caps_1: 0x08000007
> > [ 6.606959] mmc0: sdhci: Cmd: 0x0000061b | Max curr: 0x00ffffff
> > [ 6.613574] mmc0: sdhci: Resp[0]: 0x00001201 | Resp[1]: 0x00000000
> > [ 6.620190] mmc0: sdhci: Resp[2]: 0x00000000 | Resp[3]: 0x00000000
> > [ 6.626806] mmc0: sdhci: Host ctl2: 0x00003807
> > [ 6.631364] mmc0: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x00000000df062000
> > [ 6.638697] mmc0: sdhci: ============================================
> > [ 6.645379] mmc0: cache flush error -84
> >
> > Got data interrupt but no data commands are processing now. With this
> > patch, then our SD host controller can work well. Did I miss anything
> > else? Thanks.
>
> The response seems to show the card in state 9 bus-testing, which would
> suggest the use of CMD19 for eMMC. Perhaps the wrong command is used for
> eMMC re-tuning?

So it is strange, for eMMC we use CMD21 for tuning.

>
> The difficulty with changing long standing flow is that it might reveal
> problems for other existing hardware. Did you consider making a
> driver-specific change? The ->reset() callback could be used.

Understood. I will find a way to fix my issue and do not affect the
original logic used by other hardware. Thanks.

--
Baolin Wang
Best Regards