Reviewed-by: Subhash Jadavani <[email protected]>

Sougata,
There are additional blank lines before and after the
do_disable_512B_emulation() function. You may want to remove them.

Regards,
Subhash

> -----Original Message-----
> From: [email protected] [mailto:linux-mmc-
> [email protected]] On Behalf Of Saugata Das
> Sent: Wednesday, May 16, 2012 9:57 PM
> To: [email protected]; [email protected]
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]
> Subject: [PATCH 2/2] [MMC-4.5] [MMC UTIL] Disable emulation
> 
> From: Saugata Das <[email protected]>
> 
> In this patch, we add utility to disable emulation mode in the eMMC-4.5.
> This is done to increase the data sector size to 4KB.
> 
> Signed-off-by: Saugata Das <[email protected]>
> 
> changes in v2:
>       Review rework based on comments from Subhash
> ---
>  mmc.c      |    6 ++++++
>  mmc.h      |   10 ++++++++++
>  mmc_cmds.c |   51
> +++++++++++++++++++++++++++++++++++++++++++++++++++
>  mmc_cmds.h |    1 +
>  4 files changed, 68 insertions(+), 0 deletions(-)
> 
> diff --git a/mmc.c b/mmc.c
> index c27fc24..ebc7ab2 100644
> --- a/mmc.c
> +++ b/mmc.c
> @@ -65,6 +65,12 @@ static struct Command commands[] = {
>               "Set the eMMC writeprotect status of <device>.",
>         NULL
>       },
> +     { do_disable_512B_emulation, -1,
> +       "disable 512B emulation", "<device>\n"
> +             "Set the eMMC data sector size to 4KB by disabling emulation
> <device>.",
> +       NULL
> +     },
> +
>       { 0, 0, 0, 0 }
>  };
> 
> diff --git a/mmc.h b/mmc.h
> index 3af36f1..34c31d3 100644
> --- a/mmc.h
> +++ b/mmc.h
> @@ -35,6 +35,16 @@
>  #define EXT_CSD_PART_SWITCH_TIME     199
>  #define EXT_CSD_BOOT_CFG             179
>  #define EXT_CSD_BOOT_WP                      173
> +#define EXT_CSD_WR_REL_PARAM 166
> +#define EXT_CSD_NATIVE_SECTOR_SIZE   63 /* R */
> +#define EXT_CSD_USE_NATIVE_SECTOR    62 /* R/W */
> +#define EXT_CSD_DATA_SECTOR_SIZE     61 /* R */
> +
> +/*
> + * WR_REL_PARAM field definitions
> + */
> +#define HS_CTRL_REL  (1<<0)
> +#define EN_REL_WR    (1<<2)
> 
>  /*
>   * EXT_CSD field definitions
> diff --git a/mmc_cmds.c b/mmc_cmds.c
> index 4562cef..f0e64c9 100644
> --- a/mmc_cmds.c
> +++ b/mmc_cmds.c
> @@ -168,6 +168,57 @@ int do_writeprotect_set(int nargs, char **argv)
>       return ret;
>  }
> 
> +
> +int do_disable_512B_emulation(int nargs, char **argv) {
> +     __u8 ext_csd[512], native_sector_size, data_sector_size,
> wr_rel_param;
> +     int fd, ret;
> +     char *device;
> +
> +     CHECK(nargs != 2, "Usage: mmc </path/to/mmcblkX>\n", exit(1));
> +
> +     device = argv[1];
> +
> +     fd = open(device, O_RDWR);
> +     if (fd < 0) {
> +             perror("open");
> +             exit(1);
> +     }
> +
> +     ret = read_extcsd(fd, ext_csd);
> +     if (ret) {
> +             fprintf(stderr, "Could not read EXT_CSD from %s\n", device);
> +             exit(1);
> +     }
> +
> +     wr_rel_param = ext_csd[EXT_CSD_WR_REL_PARAM];
> +     native_sector_size = ext_csd[EXT_CSD_NATIVE_SECTOR_SIZE];
> +     data_sector_size = ext_csd[EXT_CSD_DATA_SECTOR_SIZE];
> +
> +     if (native_sector_size &&
> +             !data_sector_size &&
> +             (wr_rel_param & EN_REL_WR)) {
> +             ret = write_extcsd_value(fd,
> EXT_CSD_USE_NATIVE_SECTOR, 1);
> +
> +             if (ret) {
> +                     fprintf(stderr, "Could not write 0x%02x to "
> +                                     "EXT_CSD[%d] in %s\n",
> +                                     1, EXT_CSD_BOOT_WP, device);
> +                     exit(1);
> +             }
> +             printf("MMC disable 512B emulation successful\n"
> +                             "Now reset the device to switch to 4KB "
> +                             "native sector mode\n");
> +     } else if (native_sector_size && data_sector_size) {
> +             printf("MMC already disabled 512B emulation mode\n");
> +     } else {
> +             printf("MMC does not support disabling 512B emulation
> mode\n");
> +     }
> +
> +     return ret;
> +}
> +
> +
>  int do_read_extcsd(int nargs, char **argv)  {
>       __u8 ext_csd[512], ext_csd_rev, reg;
> diff --git a/mmc_cmds.h b/mmc_cmds.h
> index 66e9acb..56f46d7 100644
> --- a/mmc_cmds.h
> +++ b/mmc_cmds.h
> @@ -19,3 +19,4 @@ int do_read_extcsd(int nargs, char **argv);  int
> do_write_extcsd(int nargs, char **argv);  int do_writeprotect_get(int
nargs,
> char **argv);  int do_writeprotect_set(int nargs, char **argv);
> +int do_disable_512B_emulation(int nargs, char **argv);
> --
> 1.7.4.3
> 
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