On Wed, 17 Apr 2024 at 10:45, Felix Qin <xiaokeqinhealth@xxxxxxx> wrote:
>
> Extensive testing has shown that a few specific SD cards require
> an increase in the number of command retries to successfully
> initialize.
>
> More info:
> Platform: Rockchip SoC + DW Multimedia host Controller
> SD card: Xvv microSD CMH34A17TMA12 (Made in Korea)
> Note: The SD card is custom-made by the customer in collaboration
> with the wafer foundry.
>
> Signed-off-by: Felix Qin <xiaokeqinhealth@xxxxxxx>
> Acked-by: Avri Altman <avri.altman@xxxxxxx>
> ---
> v2: Add more info
> ---
> ---
> drivers/mmc/core/sd_ops.c | 4 ++--
> drivers/mmc/core/sd_ops.h | 8 ++++++++
> 2 files changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/core/sd_ops.c b/drivers/mmc/core/sd_ops.c
> index a59cd592f06e..b3b6e8725b80 100644
> --- a/drivers/mmc/core/sd_ops.c
> +++ b/drivers/mmc/core/sd_ops.c
> @@ -127,7 +127,7 @@ int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
> cmd.arg = ocr;
> cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;
>
> - for (i = 100; i; i--) {
> + for (i = SD_APP_OP_COND_RETRIES; i; i--) {
> err = mmc_wait_for_app_cmd(host, NULL, &cmd);
> if (err)
> break;
> @@ -147,7 +147,7 @@ int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
>
> err = -ETIMEDOUT;
>
> - mmc_delay(10);
> + mmc_delay(SD_APP_OP_COND_INTERVAL);
Rather than extending the current loop above, I would prefer if we can
move to use __mmc_poll_for_busy(), similar to what we also do for
(e)MMC and MMC_SEND_OP_COND, for example.
To help out a bit, I just posted a patch [1] making that conversion.
Please try it out and explore what values you need to set for the new
defines, "SD_APP_OP_COND_PERIOD_US" and "SD_APP_OP_COND_TIMEOUT_MS",
to make it work for you.
> }
>
> if (!i)
> diff --git a/drivers/mmc/core/sd_ops.h b/drivers/mmc/core/sd_ops.h
> index 7667fc223b74..80c5c836ccd1 100644
> --- a/drivers/mmc/core/sd_ops.h
> +++ b/drivers/mmc/core/sd_ops.h
> @@ -10,6 +10,14 @@
>
> #include <linux/types.h>
>
> +/*
> + * Extensive testing has shown that a few specific SD cards require
> + * an increase in the number of command retries to successfully
> + * initialize.
> + */
> +#define SD_APP_OP_COND_RETRIES 200
> +#define SD_APP_OP_COND_INTERVAL 10 /* millisecond */
> +
> struct mmc_card;
> struct mmc_host;
>
> --
> 2.34.1
>
Kind regards
Uffe
[1]
https://lore.kernel.org/all/20240425133034.79599-1-ulf.hansson@xxxxxxxxxx/
