[U-Boot] [PATCH ] MMC: fix user capacity for partitioned eMMC card

Jaehoon Chung jh80.chung at samsung.com
Fri Nov 21 11:50:45 CET 2014


Hi, Markus.

On 11/18/2014 11:11 PM, Markus Niebel wrote:
> From: Markus Niebel <Markus.Niebel at tq-group.com>
> 
> if the card claims to be high capacity and the card
> is partitioned the capacity shall still be read from
> ext_csd SEC_COUNT even if the resulting capacity is
> smaller than 2 GiB

I have one question. 
"smaller than 2GiB" means the size after completed partition?

Best Regards,
Jaehoon Chung

> 
> Signed-off-by: Markus Niebel <Markus.Niebel at tq-group.com>
> ---
>  drivers/mmc/mmc.c | 15 +++++++++++++++
>  include/mmc.h     |  3 +++
>  2 files changed, 18 insertions(+)
> 
> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
> index 44a4feb..24b0989 100644
> --- a/drivers/mmc/mmc.c
> +++ b/drivers/mmc/mmc.c
> @@ -1022,6 +1022,21 @@ static int mmc_startup(struct mmc *mmc)
>  			mmc->erase_grp_size =
>  				ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] *
>  					MMC_MAX_BLOCK_LEN * 1024;
> +			/*
> +			 * if high capacity and partition setting completed
> +			 * SEC_COUNT is valid even if it is smaller than 2 GiB
> +			 * JEDEC Standard JESD84-B45, 6.2.4
> +			 */
> +			if (mmc->high_capacity &&
> +			    (ext_csd[EXT_CSD_PARTITION_SETTING] &
> +			     EXT_CSD_PARTITION_SETTING_COMPLETED)) {
> +				capacity = (ext_csd[EXT_CSD_SEC_CNT]) |
> +					(ext_csd[EXT_CSD_SEC_CNT + 1] << 8) |
> +					(ext_csd[EXT_CSD_SEC_CNT + 2] << 16) |
> +					(ext_csd[EXT_CSD_SEC_CNT + 3] << 24);
> +				capacity *= MMC_MAX_BLOCK_LEN;
> +				mmc->capacity_user = capacity;
> +			}
>  		} else {
>  			/* Calculate the group size from the csd value. */
>  			int erase_gsz, erase_gmul;
> diff --git a/include/mmc.h b/include/mmc.h
> index d74a190..cb91565 100644
> --- a/include/mmc.h
> +++ b/include/mmc.h
> @@ -147,6 +147,7 @@
>   * EXT_CSD fields
>   */
>  #define EXT_CSD_GP_SIZE_MULT		143	/* R/W */
> +#define EXT_CSD_PARTITION_SETTING	155	/* R/W */
>  #define EXT_CSD_PARTITIONS_ATTRIBUTE	156	/* R/W */
>  #define EXT_CSD_PARTITIONING_SUPPORT	160	/* RO */
>  #define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
> @@ -197,6 +198,8 @@
>  #define EXT_CSD_BOOT_BUS_WIDTH_RESET(x)	(x << 2)
>  #define EXT_CSD_BOOT_BUS_WIDTH_WIDTH(x)	(x)
>  
> +#define EXT_CSD_PARTITION_SETTING_COMPLETED	(1 << 0)
> +
>  #define R1_ILLEGAL_COMMAND		(1 << 22)
>  #define R1_APP_CMD			(1 << 5)
>  
> 



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