Re: [PATCH v2 1/1] mmc: core: increase the number of retries of the ACMD41

[Dragan Simic <dsimic@manjaro.org>]

On 2024-04-17 10:45, Felix Qin 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@126.com>
> Acked-by: Avri Altman <avri.altman@wdc.com>

Looking good to me.  Thanks for including the additional details.

Reviewed-by: Dragan Simic <dsimic@manjaro.org>

> ---
> 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);
>  	}
> 
>  	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;