From 4265900e0be653f5b78baf2816857ef57cf1332f Mon Sep 17 00:00:00 2001 From: Saugata Das Date: Wed, 21 Dec 2011 13:09:17 +0530 Subject: [PATCH] mmc: MMC-4.5 Data Tag Support MMC-4.5 data tag feature will be used to store the file system meta-data in the tagged region of eMMC. This will improve the write and subsequent read transfer time for the meta data. Signed-off-by: Saugata Das Tested-by: Venkatraman S Signed-off-by: Chris Ball --- drivers/mmc/card/block.c | 21 ++++++++++++++++----- drivers/mmc/core/mmc.c | 14 ++++++++++++++ include/linux/mmc/card.h | 2 ++ include/linux/mmc/mmc.h | 3 +++ 4 files changed, 35 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index e5a3c7b6dedb..f2020d37c658 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -1080,6 +1080,7 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, struct mmc_blk_request *brq = &mqrq->brq; struct request *req = mqrq->req; struct mmc_blk_data *md = mq->data; + bool do_data_tag; /* * Reliable writes are used to implement Forced Unit Access and @@ -1155,6 +1156,16 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, if (do_rel_wr) mmc_apply_rel_rw(brq, card, req); + /* + * Data tag is used only during writing meta data to speed + * up write and any subsequent read of this meta data + */ + do_data_tag = (card->ext_csd.data_tag_unit_size) && + (req->cmd_flags & REQ_META) && + (rq_data_dir(req) == WRITE) && + ((brq->data.blocks * brq->data.blksz) >= + card->ext_csd.data_tag_unit_size); + /* * Pre-defined multi-block transfers are preferable to * open ended-ones (and necessary for reliable writes). @@ -1173,13 +1184,13 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, * We'll avoid using CMD23-bounded multiblock writes for * these, while retaining features like reliable writes. */ - - if ((md->flags & MMC_BLK_CMD23) && - mmc_op_multi(brq->cmd.opcode) && - (do_rel_wr || !(card->quirks & MMC_QUIRK_BLK_NO_CMD23))) { + if ((md->flags & MMC_BLK_CMD23) && mmc_op_multi(brq->cmd.opcode) && + (do_rel_wr || !(card->quirks & MMC_QUIRK_BLK_NO_CMD23) || + do_data_tag)) { brq->sbc.opcode = MMC_SET_BLOCK_COUNT; brq->sbc.arg = brq->data.blocks | - (do_rel_wr ? (1 << 31) : 0); + (do_rel_wr ? (1 << 31) : 0) | + (do_data_tag ? (1 << 29) : 0); brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC; brq->mrq.sbc = &brq->sbc; } diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 2b9ed1401dc4..6defddd795f6 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -519,6 +519,20 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) ext_csd[EXT_CSD_CACHE_SIZE + 1] << 8 | ext_csd[EXT_CSD_CACHE_SIZE + 2] << 16 | ext_csd[EXT_CSD_CACHE_SIZE + 3] << 24; + + if (ext_csd[EXT_CSD_DATA_SECTOR_SIZE] == 1) + card->ext_csd.data_sector_size = 4096; + else + card->ext_csd.data_sector_size = 512; + + if ((ext_csd[EXT_CSD_DATA_TAG_SUPPORT] & 1) && + (ext_csd[EXT_CSD_TAG_UNIT_SIZE] <= 8)) { + card->ext_csd.data_tag_unit_size = + ((unsigned int) 1 << ext_csd[EXT_CSD_TAG_UNIT_SIZE]) * + (card->ext_csd.data_sector_size); + } else { + card->ext_csd.data_tag_unit_size = 0; + } } out: diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index 19a41d1737af..1a1ca7169834 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -71,6 +71,8 @@ struct mmc_ext_csd { bool hpi_en; /* HPI enablebit */ bool hpi; /* HPI support bit */ unsigned int hpi_cmd; /* cmd used as HPI */ + unsigned int data_sector_size; /* 512 bytes or 4KB */ + unsigned int data_tag_unit_size; /* DATA TAG UNIT size */ unsigned int boot_ro_lock; /* ro lock support */ bool boot_ro_lockable; u8 raw_partition_support; /* 160 */ diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index fb9f6e116e1c..b822a2cb6008 100644 --- a/include/linux/mmc/mmc.h +++ b/include/linux/mmc/mmc.h @@ -274,6 +274,7 @@ struct _mmc_csd { #define EXT_CSD_FLUSH_CACHE 32 /* W */ #define EXT_CSD_CACHE_CTRL 33 /* R/W */ #define EXT_CSD_POWER_OFF_NOTIFICATION 34 /* R/W */ +#define EXT_CSD_DATA_SECTOR_SIZE 61 /* R */ #define EXT_CSD_GP_SIZE_MULT 143 /* R/W */ #define EXT_CSD_PARTITION_ATTRIBUTE 156 /* R/W */ #define EXT_CSD_PARTITION_SUPPORT 160 /* RO */ @@ -315,6 +316,8 @@ struct _mmc_csd { #define EXT_CSD_POWER_OFF_LONG_TIME 247 /* RO */ #define EXT_CSD_GENERIC_CMD6_TIME 248 /* RO */ #define EXT_CSD_CACHE_SIZE 249 /* RO, 4 bytes */ +#define EXT_CSD_TAG_UNIT_SIZE 498 /* RO */ +#define EXT_CSD_DATA_TAG_SUPPORT 499 /* RO */ #define EXT_CSD_HPI_FEATURES 503 /* RO */ /* -- 2.20.1