[U-Boot] [PATCH 3/7 V3] mmc: Enhance erase handling procedure

[Michael Trimarchi]

Hi

On Tue, Dec 10, 2013 at 6:39 AM, Haijun Zhang
<haijun.zhang at freescale.com> wrote:
> This patch enhances the currently implemented erase procedure in u-boot,
> which has the following problems/missing features..."
>
> Erass sequence:
> 1. check if erase command is support by card. If not return.
> 2. Check the erase range to see if it was aligned. The min erase size
> should be one erase group. SD card it was one block(512), mmc card
> it should be one erase group.
> 3. If not, aligned the erase rang according to the erase group size.
> 4. Send erase command to erase card once one erase group.
> 5. If it was SD card, erase with arg 0x00000000 should be send.
>    else if support secure feature, erase with arg 0x80000000(Spec eMMC 4.41).
>    else erase with arg 0x00000000.(Trim and discard is ingnored here)
> 6. Check card status after erase.
>
> Signed-off-by: Haijun Zhang <haijun.zhang at freescale.com>
> ---
> changes for V3:
>         - update the commit message and secure feature supporting judgment.
>
>  drivers/mmc/mmc_write.c | 68 +++++++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 58 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/mmc_write.c b/drivers/mmc/mmc_write.c
> index aa2fdef..c2dafa3 100644
> --- a/drivers/mmc/mmc_write.c
> +++ b/drivers/mmc/mmc_write.c
> @@ -17,6 +17,10 @@ static ulong mmc_erase_t(struct mmc *mmc, ulong start, lbaint_t blkcnt)
>         struct mmc_cmd cmd;
>         ulong end;
>         int err, start_cmd, end_cmd;
> +       uint arg = 0;
> +
> +       if (!(mmc->cmdclass & CCC_ERASE))
> +               return NOT_SUPPORT;
>
>         if (mmc->high_capacity) {
>                 end = start + blkcnt - 1;
> @@ -48,8 +52,15 @@ static ulong mmc_erase_t(struct mmc *mmc, ulong start, lbaint_t blkcnt)
>         if (err)
>                 goto err_out;
>
> +       /* SD card only support %MMC_ERASE_ARG */
> +       if (!IS_SD(mmc) &&
> +               (mmc->sec_feature_support & EXT_CSD_SEC_ER_EN))
> +               arg = MMC_SECURE_ERASE_ARG;
> +       else
> +               arg = MMC_ERASE_ARG;
> +
>         cmd.cmdidx = MMC_CMD_ERASE;
> -       cmd.cmdarg = SECURE_ERASE;
> +       cmd.cmdarg = arg;
>         cmd.resp_type = MMC_RSP_R1b;
>
>         err = mmc_send_cmd(mmc, &cmd, NULL);
> @@ -69,24 +80,61 @@ unsigned long mmc_berase(int dev_num, lbaint_t start, lbaint_t blkcnt)
>         struct mmc *mmc = find_mmc_device(dev_num);
>         lbaint_t blk = 0, blk_r = 0;
>         int timeout = 1000;
> +       int res;
> +       bool align = true;
>
>         if (!mmc)
>                 return -1;
>
> +       if (!(mmc->cmdclass & CCC_ERASE)) {
> +               printf("\nErase operation is not support by card\n");
> +               return NOT_SUPPORT;
> +       }
> +
>         if ((start % mmc->erase_grp_size) || (blkcnt % mmc->erase_grp_size))
> +               align = false;
> +
> +       res = start % mmc->erase_grp_size;
> +       if (res) {
...

Well I don't know if it works
        end = start + bkcnt;
        start += group_size - (start % group_size);
        end -= (end % group_size);
        if (start >= end)
                printf("invalid size\n");

But why not somenthing like this?
Michael

> +               start += mmc->erase_grp_size - res;
if (res < blkcnt) {

}

> +               if (blkcnt > res)
> +                       blkcnt -= res;
> +               else {
> +                       printf("\nErase size smaller than Erase group "
> +                               "size [0x%x] is not support by the device.\n",
> +                               mmc->erase_grp_size);
> +                       return NOT_SUPPORT;
> +               }
> +       }
> +
> +       res = (blkcnt - res) % mmc->erase_grp_size;
> +       if (res)
> +               blkcnt -= res;
> +
> +       if (!blkcnt) {
> +               printf("\nErase size smaller than Erase group size [0x%x] "
> +                       "is not support by the device.\n",
> +                       mmc->erase_grp_size);
> +               return NOT_SUPPORT;
> +       }
> +
> +       if (!align)
>                 printf("\n\nCaution! Your devices Erase group is 0x%x\n"
> -                      "The erase range would be change to "
> -                      "0x" LBAF "~0x" LBAF "\n\n",
> -                      mmc->erase_grp_size, start & ~(mmc->erase_grp_size - 1),
> -                      ((start + blkcnt + mmc->erase_grp_size)
> -                      & ~(mmc->erase_grp_size - 1)) - 1);
> +                       "The erase range would be change to "
> +                       "0x" LBAF "~0x" LBAF "\n\n",
> +                       mmc->erase_grp_size, start, start + blkcnt);
> +
>
>         while (blk < blkcnt) {
> -               blk_r = ((blkcnt - blk) > mmc->erase_grp_size) ?
> -                       mmc->erase_grp_size : (blkcnt - blk);
> +               if ((blkcnt - blk) >= mmc->erase_grp_size)
> +                       blk_r = mmc->erase_grp_size;
>                 err = mmc_erase_t(mmc, start + blk, blk_r);
> -               if (err)
> -                       break;
> +               if (err) {
> +                       printf("\nErase range from 0x" LBAF "~0x" LBAF
> +                               " Failed\n", start + blk, blkcnt);
> +                       return COMM_ERR;
> +               }
>
>                 blk += blk_r;
>
> --
> 1.8.4.1
>
>