[PATCH] mmc: core: Attempt to flush cache before reset

[PATCH] mmc: core: Attempt to flush cache before reset

[Adrian Hunter]

CMD0 or hardware reset may invalidate the cache, so it needs to be
flushed before reset.

In the case of recovery, we can't expect flushing the cache to work
always, but have a go and ignore errors.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/core/core.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 99275e40bf2f..1b4e0ccb0885 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2453,6 +2453,12 @@ int mmc_hw_reset(struct mmc_host *host)
 		return -EOPNOTSUPP;
 	}
 
+	/*
+	 * In the case of recovery, we can't expect flushing the cache to work
+	 * always, but we have a go and ignore errors.
+	 */
+	mmc_flush_cache(host->card);
+
 	ret = host->bus_ops->reset(host);
 	mmc_bus_put(host);
 
-- 
1.9.1

Re: [PATCH] mmc: core: Attempt to flush cache before reset

[Ulf Hansson]

On 28 April 2016 at 09:48, Adrian Hunter <adrian.hunter@intel.com> wrote:
> CMD0 or hardware reset may invalidate the cache, so it needs to be
> flushed before reset.
>
> In the case of recovery, we can't expect flushing the cache to work
> always, but have a go and ignore errors.

Makes sense!

>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
>  drivers/mmc/core/core.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 99275e40bf2f..1b4e0ccb0885 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -2453,6 +2453,12 @@ int mmc_hw_reset(struct mmc_host *host)
>                 return -EOPNOTSUPP;
>         }
>
> +       /*
> +        * In the case of recovery, we can't expect flushing the cache to work
> +        * always, but we have a go and ignore errors.
> +        */
> +       mmc_flush_cache(host->card);
> +

I prefer if you move this into mmc_reset() in drivers/mmc/core/mmc.c
instead, as it's an mmc specific operation.

>         ret = host->bus_ops->reset(host);
>         mmc_bus_put(host);
>
> --
> 1.9.1
>

Kind regards
Uffe

[PATCH V2] mmc: mmc: Attempt to flush cache before reset

[Adrian Hunter]

CMD0 or hardware reset may invalidate the cache, so it needs to be
flushed before reset.

In the case of recovery, we can't expect flushing the cache to work
always, but have a go and ignore errors.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---


Changes in V2:

	Do flush in mmc_reset() instead of mmc_hw_reset()


 drivers/mmc/core/mmc.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 0cf42af33d0f..d4d1b77c1c1e 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1965,6 +1965,12 @@ static int mmc_reset(struct mmc_host *host)
 {
 	struct mmc_card *card = host->card;
 
+	/*
+	 * In the case of recovery, we can't expect flushing the cache to work
+	 * always, but we have a go and ignore errors.
+	 */
+	mmc_flush_cache(host->card);
+
 	if ((host->caps & MMC_CAP_HW_RESET) && host->ops->hw_reset &&
 	     mmc_can_reset(card)) {
 		/* If the card accept RST_n signal, send it. */
-- 
1.9.1

Re: [PATCH V2] mmc: mmc: Attempt to flush cache before reset

[Ulf Hansson]

On 4 May 2016 at 09:38, Adrian Hunter <adrian.hunter@intel.com> wrote:
> CMD0 or hardware reset may invalidate the cache, so it needs to be
> flushed before reset.
>
> In the case of recovery, we can't expect flushing the cache to work
> always, but have a go and ignore errors.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Thanks, applied for next!

Kind regards
Uffe

> ---
>
>
> Changes in V2:
>
>         Do flush in mmc_reset() instead of mmc_hw_reset()
>
>
>  drivers/mmc/core/mmc.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 0cf42af33d0f..d4d1b77c1c1e 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -1965,6 +1965,12 @@ static int mmc_reset(struct mmc_host *host)
>  {
>         struct mmc_card *card = host->card;
>
> +       /*
> +        * In the case of recovery, we can't expect flushing the cache to work
> +        * always, but we have a go and ignore errors.
> +        */
> +       mmc_flush_cache(host->card);
> +
>         if ((host->caps & MMC_CAP_HW_RESET) && host->ops->hw_reset &&
>              mmc_can_reset(card)) {
>                 /* If the card accept RST_n signal, send it. */
> --
> 1.9.1
>
>