The cache may be flushed to the nonvolatile storage by writing to FLUSH_CACHE byte (EXT_CSD byte [32]). When in command queueing mode, the cache may be flushed by issuing a CMDQ_TASK_ DEV_MGMT (CMD48) with a FLUSH_CACHE op-code. Either way, verify that The cache function is turned ON before doing so. fixes: 1e8e55b67030 (mmc: block: Add CQE support) Reported-by: Brendan Peter <bpeter@xxxxxxxx> Tested-by: Brendan Peter <bpeter@xxxxxxxx> Signed-off-by: Avri Altman <avri.altman@xxxxxxx> --- drivers/mmc/core/block.c | 9 +++++++++ drivers/mmc/core/mmc.c | 2 +- drivers/mmc/core/mmc_ops.h | 5 +++++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 8bfd4d95b386..24e1ecbdd510 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -2186,6 +2186,11 @@ static int mmc_blk_wait_for_idle(struct mmc_queue *mq, struct mmc_host *host) return mmc_blk_rw_wait(mq, NULL); } +static bool mmc_blk_cache_disabled(struct mmc_card *card) +{ + return mmc_card_mmc(card) && !mmc_flush_allowed(card); +} + enum mmc_issued mmc_blk_mq_issue_rq(struct mmc_queue *mq, struct request *req) { struct mmc_blk_data *md = mq->blkdata; @@ -2225,6 +2230,10 @@ enum mmc_issued mmc_blk_mq_issue_rq(struct mmc_queue *mq, struct request *req) case MMC_ISSUE_ASYNC: switch (req_op(req)) { case REQ_OP_FLUSH: + if (mmc_blk_cache_disabled(mq->card)) { + blk_mq_end_request(req, BLK_STS_OK); + return MMC_REQ_FINISHED; + } ret = mmc_blk_cqe_issue_flush(mq, req); break; case REQ_OP_READ: diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 9ad4aa537867..e3da62ffcb5e 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -2037,7 +2037,7 @@ static int _mmc_flush_cache(struct mmc_card *card) { int err = 0; - if (card->ext_csd.cache_size > 0 && card->ext_csd.cache_ctrl & 1) { + if (mmc_flush_allowed(card)) { err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_FLUSH_CACHE, 1, CACHE_FLUSH_TIMEOUT_MS); diff --git a/drivers/mmc/core/mmc_ops.h b/drivers/mmc/core/mmc_ops.h index 5782fdf4e8e9..2682bf66708a 100644 --- a/drivers/mmc/core/mmc_ops.h +++ b/drivers/mmc/core/mmc_ops.h @@ -19,6 +19,11 @@ enum mmc_busy_cmd { struct mmc_host; struct mmc_card; +static inline bool mmc_flush_allowed(struct mmc_card *card) +{ + return card->ext_csd.cache_size > 0 && card->ext_csd.cache_ctrl & 1; +} + int mmc_select_card(struct mmc_card *card); int mmc_deselect_cards(struct mmc_host *host); int mmc_set_dsr(struct mmc_host *host); -- 2.25.1