Re: [PATCH v2 1/2] sdhci: tegra: Implement Tegra specific set_timeout callback

[Sowjanya Komatineni]

On 4/16/20 9:29 AM, Sowjanya Komatineni wrote:
> On 4/16/20 3:59 AM, Ulf Hansson wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On Wed, 15 Apr 2020 at 19:55, Naresh Kamboju 
> > <naresh.kamboju@xxxxxxxxxx> wrote:
> > > On Fri, 13 Mar 2020 at 06:41, Sowjanya Komatineni
> > > <skomatineni@xxxxxxxxxx> wrote:
> > > > Tegra host supports HW busy detection and timeouts based on the
> > > > count programmed in SDHCI_TIMEOUT_CONTROL register and max busy
> > > > timeout it supports is 11s in finite busy wait mode.
> > > >
> > > > Some operations like SLEEP_AWAKE, ERASE and flush cache through
> > > > SWITCH commands take longer than 11s and Tegra host supports
> > > > infinite HW busy wait mode where HW waits forever till the card
> > > > is busy without HW timeout.
> > > >
> > > > This patch implements Tegra specific set_timeout sdhci_ops to allow
> > > > switching between finite and infinite HW busy detection wait modes
> > > > based on the device command expected operation time.
> > > >
> > > > Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
> > > > ---
> > > > Â drivers/mmc/host/sdhci-tegra.c | 31 +++++++++++++++++++++++++++++++
> > > > Â 1 file changed, 31 insertions(+)
> > > >
> > > > diff --git a/drivers/mmc/host/sdhci-tegra.c 
> > > > b/drivers/mmc/host/sdhci-tegra.c
> > > > index a25c3a4..fa8f6a4 100644
> > > > --- a/drivers/mmc/host/sdhci-tegra.c
> > > > +++ b/drivers/mmc/host/sdhci-tegra.c
> > > > @@ -45,6 +45,7 @@
> > > > Â #define SDHCI_TEGRA_CAP_OVERRIDES_DQS_TRIM_SHIFTÂÂÂÂÂÂ 8
> > > >
> > > > Â #define SDHCI_TEGRA_VENDOR_MISC_CTRL 0x120
> > > > +#define SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT BIT(0)
> > > > Â #define SDHCI_MISC_CTRL_ENABLE_SDR104ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 0x8
> > > > Â #define SDHCI_MISC_CTRL_ENABLE_SDR50 0x10
> > > > Â #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300 0x20
> > > > @@ -1227,6 +1228,34 @@ static u32 sdhci_tegra_cqhci_irq(struct 
> > > > sdhci_host *host, u32 intmask)
> > > > ÂÂÂÂÂÂÂÂ return 0;
> > > > Â }
> > > >
> > > > +static void tegra_sdhci_set_timeout(struct sdhci_host *host,
> > > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct mmc_command *cmd)
> > > > +{
> > > > +ÂÂÂÂÂÂ u32 val;
> > > > +
> > > > +ÂÂÂÂÂÂ /*
> > > > +ÂÂÂÂÂÂÂ * HW busy detection timeout is based on programmed data 
> > > > timeout
> > > > +ÂÂÂÂÂÂÂ * counter and maximum supported timeout is 11s which may 
> > > > not be
> > > > +ÂÂÂÂÂÂÂ * enough for long operations like cache flush, sleep 
> > > > awake, erase.
> > > > +ÂÂÂÂÂÂÂ *
> > > > +ÂÂÂÂÂÂÂ * ERASE_TIMEOUT_LIMIT bit of VENDOR_MISC_CTRL register allows
> > > > +ÂÂÂÂÂÂÂ * host controller to wait for busy state until the card is 
> > > > busy
> > > > +ÂÂÂÂÂÂÂ * without HW timeout.
> > > > +ÂÂÂÂÂÂÂ *
> > > > +ÂÂÂÂÂÂÂ * So, use infinite busy wait mode for operations that may 
> > > > take
> > > > +ÂÂÂÂÂÂÂ * more than maximum HW busy timeout of 11s otherwise use 
> > > > finite
> > > > +ÂÂÂÂÂÂÂ * busy wait mode.
> > > > +ÂÂÂÂÂÂÂ */
> > > > +ÂÂÂÂÂÂ val = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
> > > > +ÂÂÂÂÂÂ if (cmd && cmd->busy_timeout >= 11 * HZ)
> > > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂ val |= SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT;
> > > > +ÂÂÂÂÂÂ else
> > > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂ val &= ~SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT;
> > > > +ÂÂÂÂÂÂ sdhci_writel(host, val, SDHCI_TEGRA_VENDOR_MISC_CTRL);
> > > > +
> > > > +ÂÂÂÂÂÂ __sdhci_set_timeout(host, cmd);
> > > kernel build on arm and arm64 architecture failed on stable-rc 4.19
> > > (arm), 5.4 (arm64) and 5.5 (arm64)
> > >
> > > drivers/mmc/host/sdhci-tegra.c: In function 'tegra_sdhci_set_timeout':
> > > drivers/mmc/host/sdhci-tegra.c:1256:2: error: implicit declaration of
> > > function '__sdhci_set_timeout'; did you mean
> > > 'tegra_sdhci_set_timeout'? [-Werror=implicit-function-declaration]
> > > ÂÂ __sdhci_set_timeout(host, cmd);
> > > ÂÂ ^~~~~~~~~~~~~~~~~~~
> > > ÂÂ tegra_sdhci_set_timeout
> > >
> > > Full build log,
> > > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.5/DISTRO=lkft,MACHINE=am57xx-evm,label=docker-lkft/83/consoleText 
> > >
> > > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.4/DISTRO=lkft,MACHINE=juno,label=docker-lkft/158/consoleText 
> > >
> > > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-4.19/DISTRO=lkft,MACHINE=am57xx-evm,label=docker-lkft/511/consoleText 
> > >
> > >
> > > - Naresh
> > Thanks for reporting! What a mess.
> >
> > It turns out that the commit that was queued for stable that is
> > causing the above errors, also requires another commit.
> >
> > The commit that was queued:
> > 5e958e4aacf4 ("sdhci: tegra: Implement Tegra specific set_timeout 
> > callback")
> >
> > The additional commit needed (which was added in v5.6-rc1):
> > 7d76ed77cfbd ("mmc: sdhci: Refactor sdhci_set_timeout()")
> >
> > However, the above commit needs a manual backport (quite trivial, but
> > still) for the relevant stable kernels, to allow it to solve the build
> > problems.
> >
> > Greg, Sasha - I suggest you to drop the offending commit from the
> > stable kernels, for now. I think it's better to let Sowjanya deal with
> > the backports, then send them in small series instead.
> >
> > Kind regards
> > Uffe
>
> Hi Ufee,
>
> Will back-porting below commit cause any issues to other vendors?
>
> 7d76ed77cfbd ("mmc: sdhci: Refactor sdhci_set_timeout()")
sdhci-tegra driver in 4.19 is using same sdhci_ops for Tegra114 and 
Tegra210 and separate sdhci_ops for T210 started from 4.20.

5e958e4aacf4 ("sdhci: tegra: Implement Tegra specific set_timeout callback")

So above commit can't be applied to 4.19. So probably a separate patch 
need to be created to apply for 4.19 and back port above commit along 
with its dependency commit (7d76ed77cfbd ("mmc: sdhci: Refactor 
sdhci_set_timeout()") for 5.4 and 5.4.


> Thanks
Sowjanya
>