diff options
| author | Michael Wu <michael@allwinnertech.com> | 2022-03-31 15:32:23 +0800 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2022-04-04 13:27:58 +0200 |
| commit | 08ebf903af57cda6d773f3dd1671b64f73b432b8 (patch) | |
| tree | 08402b479f8f78572e79f923ce74d911bdd9e26d /drivers/mmc/core/block.c | |
| parent | 5d435933376962b107bd76970912e7e80247dcc7 (diff) | |
mmc: core: Fixup support for writeback-cache for eMMC and SD
During the card initialization process, the mmc core checks whether the
eMMC/SD card supports an internal writeback-cache and then enables it
inside the card.
Unfortunately, this isn't according to what the mmc core reports to the
upper block layer. Instead, the writeback-cache support with REQ_FLUSH and
REQ_FUA, are being enabled depending on whether the host supports the CMD23
(MMC_CAP_CMD23) and whether an eMMC supports the reliable-write command.
This is wrong and it may also sound awkward. In fact, it's a remnant
from when both eMMC/SD cards didn't have dedicated commands/support to
control the internal writeback-cache. In other words, it was the best we
could do at that point in time.
To fix the problem, but also without breaking backwards compatibility,
let's align the REQ_FLUSH support with whether the writeback-cache became
successfully enabled - for both eMMC and SD cards.
Cc: stable@kernel.org
Fixes: 881d1c25f765 ("mmc: core: Add cache control for eMMC4.5 device")
Fixes: 130206a615a9 ("mmc: core: Add support for cache ctrl for SD cards")
Depends-on: 97fce126e279 ("mmc: block: Issue a cache flush only when it's enabled")
Reviewed-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Michael Wu <michael@allwinnertech.com>
Link: https://lore.kernel.org/r/20220331073223.106415-1-michael@allwinnertech.com
[Ulf: Re-wrote the commit message]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc/core/block.c')
| -rw-r--r-- | drivers/mmc/core/block.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index be2078684417..db99882c95d8 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -2382,6 +2382,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, struct mmc_blk_data *md; int devidx, ret; char cap_str[10]; + bool cache_enabled = false; + bool fua_enabled = false; devidx = ida_simple_get(&mmc_blk_ida, 0, max_devices, GFP_KERNEL); if (devidx < 0) { @@ -2461,13 +2463,17 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, md->flags |= MMC_BLK_CMD23; } - if (mmc_card_mmc(card) && - md->flags & MMC_BLK_CMD23 && + if (md->flags & MMC_BLK_CMD23 && ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) || card->ext_csd.rel_sectors)) { md->flags |= MMC_BLK_REL_WR; - blk_queue_write_cache(md->queue.queue, true, true); + fua_enabled = true; + cache_enabled = true; } + if (mmc_cache_enabled(card->host)) + cache_enabled = true; + + blk_queue_write_cache(md->queue.queue, cache_enabled, fua_enabled); string_get_size((u64)size, 512, STRING_UNITS_2, cap_str, sizeof(cap_str)); |