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

[Naresh Kamboju]

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>
> ---
>  drivers/mmc/host/sdhci-tegra.c | 31 +++++++++++++++++++++++++++++++
>  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 @@
>  #define SDHCI_TEGRA_CAP_OVERRIDES_DQS_TRIM_SHIFT       8
>
>  #define SDHCI_TEGRA_VENDOR_MISC_CTRL                   0x120
> +#define SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT            BIT(0)
>  #define SDHCI_MISC_CTRL_ENABLE_SDR104                  0x8

>  #define SDHCI_MISC_CTRL_ENABLE_SDR50                   0x10
>  #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)
>         return 0;
>  }
>
> +static void tegra_sdhci_set_timeout(struct sdhci_host *host,
> +                                   struct mmc_command *cmd)
> +{
> +       u32 val;
> +
> +       /*
> +        * HW busy detection timeout is based on programmed data timeout
> +        * counter and maximum supported timeout is 11s which may not be
> +        * enough for long operations like cache flush, sleep awake, erase.
> +        *
> +        * ERASE_TIMEOUT_LIMIT bit of VENDOR_MISC_CTRL register allows
> +        * host controller to wait for busy state until the card is busy
> +        * without HW timeout.
> +        *
> +        * So, use infinite busy wait mode for operations that may take
> +        * more than maximum HW busy timeout of 11s otherwise use finite
> +        * busy wait mode.
> +        */
> +       val = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
> +       if (cmd && cmd->busy_timeout >= 11 * HZ)
> +               val |= SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT;
> +       else
> +               val &= ~SDHCI_MISC_CTRL_ERASE_TIMEOUT_LIMIT;
> +       sdhci_writel(host, val, SDHCI_TEGRA_VENDOR_MISC_CTRL);
> +
> +       __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]
  __sdhci_set_timeout(host, cmd);
  ^~~~~~~~~~~~~~~~~~~
  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