RE: [PATCH v2 03/10] mmc: sd: Add Extension memory addressing

[Ricky WU <ricky_wu@realtek.com>]

> SDUC memory addressing spans beyond 2TB and up to 128TB.  Therefore, 38
> bits are required to access the entire memory space of all sectors.
> Those extra 6 bits are to be carried by CMD22 prior of sending
> read/write/erase commands: CMD17, CMD18, CMD24, CMD25, CMD32, and
> CMD33.
> 
> CMD22 will carry the higher order 6 bits, and must precedes any of the above
> commands even if it targets sector < 2TB.
> 
> No error related to address or length is indicated in CMD22 but rather in the
> read/write command itself.
> 
> Signed-off-by: Avri Altman <avri.altman@wdc.com>
> ---
>  drivers/mmc/core/sd_ops.c | 15 +++++++++++++++
> drivers/mmc/core/sd_ops.h |  1 +
>  include/linux/mmc/sd.h    |  3 +++
>  3 files changed, 19 insertions(+)
> 
> diff --git a/drivers/mmc/core/sd_ops.c b/drivers/mmc/core/sd_ops.c index
> 7f6963dac873..8b69129d7b61 100644
> --- a/drivers/mmc/core/sd_ops.c
> +++ b/drivers/mmc/core/sd_ops.c
> @@ -199,6 +199,21 @@ int mmc_send_app_op_cond(struct mmc_host *host,
> u32 ocr, u32 *rocr)
>         return 0;
>  }
> 
> +int mmc_send_ext_addr(struct mmc_host *host, sector_t addr) {
> +       struct mmc_command cmd = {
> +               .opcode = SD_ADDR_EXT,
> +               .arg = (u32)((addr >> 32) & 0x3F),
> +               .flags = MMC_RSP_R1 | MMC_CMD_AC,
> +       };
> +
> +       if (!mmc_card_is_sduc(host))
> +               return 0;
> +
I think here can be removed, all mmc_send_ext_addr caller are have if-statement to check the card is SDUC

> +       return mmc_wait_for_cmd(host, &cmd, 0); }
> +EXPORT_SYMBOL_GPL(mmc_send_ext_addr);
> +
>  static int __mmc_send_if_cond(struct mmc_host *host, u32 ocr, u8 pcie_bits,
>                               u32 *resp)  { diff --git
> a/drivers/mmc/core/sd_ops.h b/drivers/mmc/core/sd_ops.h index
> 7667fc223b74..462efd43acfa 100644
> --- a/drivers/mmc/core/sd_ops.h
> +++ b/drivers/mmc/core/sd_ops.h
> @@ -21,6 +21,7 @@ int mmc_send_relative_addr(struct mmc_host *host,
> unsigned int *rca);  int mmc_app_send_scr(struct mmc_card *card);  int
> mmc_app_sd_status(struct mmc_card *card, void *ssr);  int
> mmc_app_cmd(struct mmc_host *host, struct mmc_card *card);
> +int mmc_send_ext_addr(struct mmc_host *host, sector_t addr);
> 
>  #endif
> 
> diff --git a/include/linux/mmc/sd.h b/include/linux/mmc/sd.h index
> 865cc0ca8543..af5fc70e09a2 100644
> --- a/include/linux/mmc/sd.h
> +++ b/include/linux/mmc/sd.h
> @@ -15,6 +15,9 @@
>  #define SD_SEND_IF_COND           8   /* bcr  [11:0] See below   R7
> */
>  #define SD_SWITCH_VOLTAGE         11  /* ac
> R1  */
> 
> +/* Class 2 */
> +#define SD_ADDR_EXT             22   /* ac   [5:0]
> R1  */
> +
>    /* class 10 */
>  #define SD_SWITCH                 6   /* adtc [31:0] See below   R1
> */
> 
> --
> 2.25.1