Re: [PATCH] mmc: mmc: Fix partition switch time

Ulf Hansson
2021-03-04T13:53:06Z

On Wed, 3 Mar 2021 at 10:26, Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> Avoid the following warning by always defining partition switch time:
>
> [ 3.209874] mmc1: unspecified timeout for CMD6 - use generic
> [ 3.222780] ------------[ cut here ]------------
> [ 3.233363] WARNING: CPU: 1 PID: 111 at drivers/mmc/core/mmc_ops.c:575 __mmc_switch+0x200/0x204
>
> Reported-by: Paul Fertser <fercerpav@gmail.com>
> Fixes: 1c447116d017 ("mmc: mmc: Fix partition switch timeout for some eMMCs")
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Applied for next and by adding a stable tag, thanks!

Kind regards
Uffe

> ---
> drivers/mmc/core/mmc.c | 15 +++++++++++----
> 1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 0d80b72ddde8..8741271d3971 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -423,10 +423,6 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
>
> /* EXT_CSD value is in units of 10ms, but we store in ms */
> card->ext_csd.part_time = 10 * ext_csd[EXT_CSD_PART_SWITCH_TIME];
> - /* Some eMMC set the value too low so set a minimum */
> - if (card->ext_csd.part_time &&
> - card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME)
> - card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME;
>
> /* Sleep / awake timeout in 100ns units */
> if (sa_shift > 0 && sa_shift <= 0x17)
> @@ -616,6 +612,17 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
> card->ext_csd.data_sector_size = 512;
> }
>
> + /*
> + * GENERIC_CMD6_TIME is to be used "unless a specific timeout is defined
> + * when accessing a specific field", so use it here if there is no
> + * PARTITION_SWITCH_TIME.
> + */
> + if (!card->ext_csd.part_time)
> + card->ext_csd.part_time = card->ext_csd.generic_cmd6_time;
> + /* Some eMMC set the value too low so set a minimum */
> + if (card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME)
> + card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME;
> +
> /* eMMC v5 or later */
> if (card->ext_csd.rev >= 7) {
> memcpy(card->ext_csd.fwrev, &ext_csd[EXT_CSD_FIRMWARE_VERSION],
> --
> 2.17.1
>
>