Re: [PATCH V6 05/24] mmc: core: Add definitions for SD UHS-II cards

[Ulf Hansson]

On Tue, 13 Dec 2022 at 10:01, Victor Shih <victorshihgli@xxxxxxxxx> wrote:
>
> Add UHS-II specific data structures for commands and defines for
> registers, as described in Part 1 UHS-II Addendum Version 1.01.
>
> UHS-II related definitions are listed below:
>   1. UHS-II card capability: sd_uhs2_caps{}
>   2. UHS-II configuration: sd_uhs2_config{}
>   3. UHS-II Command structure: uhs2_command{}
>   4. UHS-II register I/O address and register field definitions: sd_uhs2.h
>
> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Signed-off-by: Jason Lai <jason.lai@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>

[...]

> --- a/include/linux/mmc/core.h
> +++ b/include/linux/mmc/core.h
> @@ -23,6 +23,14 @@ enum mmc_blk_status {
>         MMC_BLK_NEW_REQUEST,
>  };
>
> +struct uhs2_command {
> +       u16     header;
> +       u16     arg;
> +       __be32  *payload;
> +       u32     payload_len;
> +       u32     packet_len;
> +};
> +
>  struct mmc_command {
>         u32                     opcode;
>         u32                     arg;
> @@ -109,6 +117,11 @@ struct mmc_command {
>         unsigned int            busy_timeout;   /* busy detect timeout in ms */
>         struct mmc_data         *data;          /* data segment associated with cmd */
>         struct mmc_request      *mrq;           /* associated request */
> +
> +       struct uhs2_command     *uhs2_cmd;      /* UHS2 command */
> +       u8                      *uhs2_resp;     /* UHS2 native cmd resp */
> +       u8                      uhs2_resp_len;  /* UHS2 native cmd resp len */
> +       u8                      uhs2_tmode0_flag; /* UHS2 transfer mode flag */

I forgot to comment on this flag in my earlier reply. It looks like
the flag is being set for "MMC_CMD_ADTC" commands. This makes me
wonder, why can't we keep using cmd->flags to check this, rather than
adding a new flag solely for UHS2? Or is there a problem with this?

I will continue to comment around this at patch7 too.

[...]

Kind regards
Uffe