Re: [External] : Re: [PATCH v2] mmc-utils: Add eMMC erase command support

[Ulf Hansson]

On Tue, 30 Mar 2021 at 23:36, <kimito.sakata@xxxxxxxxxx> wrote:
>
>
>
> On 3/30/2021 6:39 AM, Ulf Hansson wrote:
> > On Wed, 24 Mar 2021 at 17:45, Bean Huo <huobean@xxxxxxxxx> wrote:
> >> From: Kimito Sakata <kimito.sakata@xxxxxxxxxx>
> >>
> >> we have been using this erase feature for a while, but it is
> >> still not merged into the upstream mmc-utils. Especially, for
> >> the customer, every time when they update the mmc-utils, they
> >> should re-install this patch again, let's try to make this
> >> erase command upstreamed in the mmc-utils.
> >>
> >> Co-developed-by: Bean Huo <beanhuo@xxxxxxxxxx>
> >> Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
> >> Reviewed-by: Kenneth Gibbons <kenny.gibbons@xxxxxxxxxx>
> >> ---
> >>
> >> Hi Ulf,
> >> Please help us review this mmc-utils patch, and if agree, it is
> >> possible to make it merged in the official mmc-utils.
> >>
> >> Changelog:
> >>
> >> V1--V2:
> >>      1. refactor Kimito's original patch
> >>      2. change to use MMC_IOC_MULTI_CMD
> >>      3. add checkup if eMMC devie supports secure erase/trim
> >>
> >> ---
> >>   mmc.c      |   8 ++++
> >>   mmc.h      |  13 +++++-
> >>   mmc_cmds.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >>   mmc_cmds.h |   1 +
> >>   4 files changed, 156 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/mmc.c b/mmc.c
> >> index 50c9c9e..cb29a65 100644
> >> --- a/mmc.c
> >> +++ b/mmc.c
> >> @@ -215,6 +215,14 @@ static struct Command commands[] = {
> >>                  "Run Field Firmware Update with <image name> on <device>.\n",
> >>            NULL
> >>          },
> >> +       { do_erase, -4,
> >> +       "erase", "<type> " "<start address> " "<end address> " "<device>\n"
> >> +               "Send Erase CMD38 with specific argument to the <device>\n\n"
> >> +               "NOTE!: This will delete all user data in the specified region of the device\n"
> >> +               "<type> must be: legacy | discard | secure-erase | "
> >> +               "secure-trim1 | secure-trim2 | trim \n",
> >> +       NULL
> >> +       },
> >>          { 0, 0, 0, 0 }
> >>   };
> >>
> >> diff --git a/mmc.h b/mmc.h
> >> index 648fb26..90b7fb5 100644
> >> --- a/mmc.h
> >> +++ b/mmc.h
> >> @@ -34,7 +34,15 @@
> >>   #define MMC_SET_WRITE_PROT     28    /* ac   [31:0] data addr   R1b */
> >>   #define MMC_CLEAR_WRITE_PROT   29    /* ac   [31:0] data addr   R1b */
> >>   #define MMC_SEND_WRITE_PROT_TYPE 31   /* ac   [31:0] data addr   R1  */
> >> -
> >> +#define MMC_ERASE_GROUP_START  35    /* ac   [31:0] data addr   R1  */
> >> +#define MMC_ERASE_GROUP_END    36    /* ac   [31:0] data addr   R1  */
> >> +#define MMC_ERASE              38    /* ac   [31] Secure request
> >> +                                             [30:16] set to 0
> >> +                                             [15] Force Garbage Collect request
> >> +                                             [14:2] set to 0
> >> +                                             [1] Discard Enable
> >> +                                             [0] Identify Write Blocks for
> >> +                                             Erase (or TRIM Enable)  R1b */
> >>   /*
> >>    * EXT_CSD fields
> >>    */
> >> @@ -61,6 +69,7 @@
> >>   #define EXT_CSD_CACHE_SIZE_2           251
> >>   #define EXT_CSD_CACHE_SIZE_1           250
> >>   #define EXT_CSD_CACHE_SIZE_0           249
> >> +#define EXT_CSD_SEC_FEATURE_SUPPORT    231
> >>   #define EXT_CSD_BOOT_INFO              228     /* R/W */
> >>   #define EXT_CSD_HC_ERASE_GRP_SIZE      224
> >>   #define EXT_CSD_HC_WP_GRP_SIZE         221
> >> @@ -177,6 +186,8 @@
> >>   #define EXT_CSD_REV_V4_2               2
> >>   #define EXT_CSD_REV_V4_1               1
> >>   #define EXT_CSD_REV_V4_0               0
> >> +#define EXT_CSD_SEC_GB_CL_EN           (1<<4)
> >> +#define EXT_CSD_SEC_ER_EN              (1<<0)
> >>
> >>
> >>   /* From kernel linux/mmc/core.h */
> >> diff --git a/mmc_cmds.c b/mmc_cmds.c
> >> index fb37189..17986e3 100644
> >> --- a/mmc_cmds.c
> >> +++ b/mmc_cmds.c
> >> @@ -2435,6 +2435,141 @@ int do_cache_dis(int nargs, char **argv)
> >>          return do_cache_ctrl(0, nargs, argv);
> >>   }
> >>
> >> +static int erase(int dev_fd, __u32 argin, __u32 start, __u32 end)
> >> +{
> >> +#ifndef MMC_IOC_MULTI_CMD
> > In kernel v4.4 we added the multi cmd support, which is quite some
> > time ago. So, I think it's time to drop these ifdef hackary from the
> > userland tool. At least, we shouldn't need it for new kinds of
> > features that we add.
> Ulf
> Do you want us to take out the  MMC_IOC_MULTI_CMD ifdef and resubmit?

Yes, please.

Moreover, we should probably also remove all the other #ifndef
MMC_IOC_MULTI_CMD hacks that we currently have in the code. But that's
a separate patch.

> Kimito
>
> >
> >> +       fprintf(stderr, "mmc-utils has been compiled without MMC_IOC_MULTI_CMD"
> >> +                       " support, needed by erase.\n");
> >> +       return -ENOTSUP;
> >> +#else
> >> +       int ret = 0;
> >> +       struct mmc_ioc_multi_cmd *multi_cmd;
> >> +
> > [...]

Kind regards
Uffe