On 2016/6/15 21:01, Ritesh Harjani wrote:
From: Asutosh Das <asutoshd@xxxxxxxxxxxxxx> eMMC cards with EXT_CSD version >= 7, optionally support command queuing feature as defined by JEDEC eMMC5.1. Add support for probing command queue feature for such type of cards. Signed-off-by: Sujit Reddy Thumma <sthumma@xxxxxxxxxxxxxx> Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx> Signed-off-by: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx> [subhashj@xxxxxxxxxxxxxx: fixed trivial merge conflicts] Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx> --- drivers/mmc/core/mmc.c | 18 ++++++++++++++++++ include/linux/mmc/card.h | 2 ++ include/linux/mmc/mmc.h | 3 +++ 3 files changed, 23 insertions(+) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 4dbe3df..ff560e9 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -578,6 +578,24 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd) card->ext_csd.data_sector_size = 512; } + if (card->ext_csd.rev >= 7) {
Do you ever find one device claiming to support it with ext_csd.rev to be 7? I believe it should be 8 as 7 is for 5.0 and 5.01 which don't support hw-cmdq.
+ card->ext_csd.cmdq_support = ext_csd[EXT_CSD_CMDQ_SUPPORT]; + if (card->ext_csd.cmdq_support) { + /* + * Queue Depth = N + 1, + * see JEDEC JESD84-B51 section 7.4.19 + */ + card->ext_csd.cmdq_depth = + ext_csd[EXT_CSD_CMDQ_DEPTH] + 1; + pr_info("%s: CMDQ supported: depth: %d\n", + mmc_hostname(card->host), + card->ext_csd.cmdq_depth);
pr_debug may be more appropriate?
+ } + } else { + card->ext_csd.cmdq_support = 0; + card->ext_csd.cmdq_depth = 0; + }
if the code fallback to here, card->ext_csd.cmdq_support must be zero already, and the ext_csd is already set to zero which also means you not need to zero it again here.
+ /* eMMC v5 or later */ if (card->ext_csd.rev >= 7) { memcpy(card->ext_csd.fwrev, &ext_csd[EXT_CSD_FIRMWARE_VERSION], diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index eb0151b..f74db84 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -118,6 +118,8 @@ struct mmc_ext_csd { u8 raw_pwr_cl_ddr_200_360; /* 253 */ u8 raw_bkops_status; /* 246 */ u8 raw_sectors[4]; /* 212 - 4 bytes */ + u8 cmdq_depth; /* 307 */ + u8 cmdq_support; /* 308 */ unsigned int feature_support; #define MMC_DISCARD_FEATURE BIT(0) /* CMD38 feature */ diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index 15f2c4a..1c0ae75 100644 --- a/include/linux/mmc/mmc.h +++ b/include/linux/mmc/mmc.h @@ -330,6 +330,9 @@ struct _mmc_csd { #define EXT_CSD_CACHE_SIZE 249 /* RO, 4 bytes */ #define EXT_CSD_PWR_CL_DDR_200_360 253 /* RO */ #define EXT_CSD_FIRMWARE_VERSION 254 /* RO, 8 bytes */ +#define EXT_CSD_CMDQ_DEPTH 307 /* RO */ +#define EXT_CSD_CMDQ_SUPPORT 308 /* RO */ + #define EXT_CSD_TAG_UNIT_SIZE 498 /* RO */
an invalid space here
#define EXT_CSD_SUPPORTED_MODE 493 /* RO */ #define EXT_CSD_TAG_UNIT_SIZE 498 /* RO */ #define EXT_CSD_DATA_TAG_SUPPORT 499 /* RO */
-- Best Regards Shawn Lin -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html