diff options
| author | Saugata Das <saugata.das@linaro.org> | 2011-12-21 13:09:17 +0530 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2012-03-25 19:33:44 -0400 |
| commit | 4265900e0be653f5b78baf2816857ef57cf1332f (patch) | |
| tree | 156dc60c8f5b24aa0c8be7d18759faae6ecff5f7 /drivers/mmc/card | |
| parent | e2a0883e4071237d09b604a342c28b96b44a04b3 (diff) | |
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 <saugata.das@linaro.org>
Tested-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc/card')
| -rw-r--r-- | drivers/mmc/card/block.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index e5a3c7b6ded..f2020d37c65 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 @@ -1156,6 +1157,16 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, 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). * However, it is not sufficient to just send CMD23, @@ -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; } |