From: Bean Huo <beanhuo@xxxxxxxxxx>
Micron MTFC4GACAJCN eMMC supports cache but requires that flush cache
operation be allowed only after a write has occurred. Otherwise, the
cache flush command or subsequent commands will time out.
Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
Signed-off-by: Rafael Beims <rafael.beims@xxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
Changelog:
v4--v5:
1. In the case of a successful flush, set writing_flag in _mmc_flush_cache()
v3--v4:
1. Add helper function for this quirk in drivers/mmc/core/card.h.
2. Set card->written_flag only for REQ_OP_WRITE.
v2--v3:
1. Set card->written_flag in mmc_blk_mq_issue_rq().
v1--v2:
1. Add Rafael's test-tag, and Co-developed-by.
2. Check host->card whether NULL or not in __mmc_start_request() before asserting host->card->->quirks
---
drivers/mmc/core/block.c | 4 +++-
drivers/mmc/core/card.h | 4 ++++
drivers/mmc/core/mmc.c | 8 ++++++--
drivers/mmc/core/quirks.h | 7 ++++---
include/linux/mmc/card.h | 2 ++
5 files changed, 19 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 3a8f27c3e310..152dfe593c43 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -2381,8 +2381,10 @@ enum mmc_issued mmc_blk_mq_issue_rq(struct mmc_queue *mq, struct request *req)
}
ret = mmc_blk_cqe_issue_flush(mq, req);
break;
- case REQ_OP_READ:
case REQ_OP_WRITE:
+ card->written_flag = true;
+ fallthrough;
+ case REQ_OP_READ:
if (host->cqe_enabled)
ret = mmc_blk_cqe_issue_rw_rq(mq, req);
else
diff --git a/drivers/mmc/core/card.h b/drivers/mmc/core/card.h
index 4edf9057fa79..b7754a1b8d97 100644
--- a/drivers/mmc/core/card.h
+++ b/drivers/mmc/core/card.h
@@ -280,4 +280,8 @@ static inline int mmc_card_broken_sd_cache(const struct mmc_card *c)
return c->quirks & MMC_QUIRK_BROKEN_SD_CACHE;
}
+static inline int mmc_card_broken_cache_flush(const struct mmc_card *c)
+{
+ return c->quirks & MMC_QUIRK_BROKEN_CACHE_FLUSH;
+}
#endif
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 8180983bd402..11053f920ac4 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -2086,13 +2086,17 @@ static int _mmc_flush_cache(struct mmc_host *host)
{
int err = 0;
+ if (mmc_card_broken_cache_flush(host->card) && !host->card->written_flag)
+ return err;
+
if (_mmc_cache_enabled(host)) {
err = mmc_switch(host->card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_FLUSH_CACHE, 1,
CACHE_FLUSH_TIMEOUT_MS);
if (err)
- pr_err("%s: cache flush error %d\n",
- mmc_hostname(host), err);
+ pr_err("%s: cache flush error %d\n", mmc_hostname(host), err);
+ else
+ host->card->written_flag = false;
}
return err;
diff --git a/drivers/mmc/core/quirks.h b/drivers/mmc/core/quirks.h
index 32b64b564fb1..5e68c8b4cdca 100644
--- a/drivers/mmc/core/quirks.h
+++ b/drivers/mmc/core/quirks.h
@@ -110,11 +110,12 @@ static const struct mmc_fixup __maybe_unused mmc_blk_fixups[] = {
MMC_QUIRK_TRIM_BROKEN),
/*
- * Micron MTFC4GACAJCN-1M advertises TRIM but it does not seems to
- * support being used to offload WRITE_ZEROES.
+ * Micron MTFC4GACAJCN-1M supports TRIM but does not appear to suppor
+ * WRITE_ZEROES offloading. It also supports caching, but the cache can
+ * only be flushed after a write has occurred.
*/
MMC_FIXUP("Q2J54A", CID_MANFID_MICRON, 0x014e, add_quirk_mmc,
- MMC_QUIRK_TRIM_BROKEN),
+ MMC_QUIRK_TRIM_BROKEN | MMC_QUIRK_BROKEN_CACHE_FLUSH),
/*
* Kingston EMMC04G-M627 advertises TRIM but it does not seems to
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index daa2f40d9ce6..7b12eebc5586 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -295,7 +295,9 @@ struct mmc_card {
#define MMC_QUIRK_BROKEN_HPI (1<<13) /* Disable broken HPI support */
#define MMC_QUIRK_BROKEN_SD_DISCARD (1<<14) /* Disable broken SD discard support */
#define MMC_QUIRK_BROKEN_SD_CACHE (1<<15) /* Disable broken SD cache support */
+#define MMC_QUIRK_BROKEN_CACHE_FLUSH (1<<16) /* Don't flush cache until the write has occurred */
+ bool written_flag; /* Indicates eMMC has been written since power on */
bool reenable_cmdq; /* Re-enable Command Queue */
unsigned int erase_size; /* erase size in sectors */
--
2.34.1
