We to some extent should tolerate R1_OUT_OF_RANGE for open-ending
mode as it is expected behaviour and most of the backup partition
tables should be located near some of the last blocks which will
always make open-ending read exceed the capacity of cards.
Fixes: 9820a5b11101 ("mmc: core: for data errors, take response of stop cmd into account")
Fixes: a04e6bae9e6f ("mmc: core: check also R1 response for stop commands")
Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Tested-by: Shawn Guo <shawnguo@xxxxxxxxxx>
---
Changes in v4:
- improve for more readable and remove Yoshihiro's tag, add Wolfram's
tag
Changes in v3:
- add explanation for why don't check predefined method
- check brq->mrq.sbc for easier to read suggested by Wolfram
Changes in v2:
- fix a typo and introduce STOP_ERROR
- reword the comment and always include a description from the spec if possible
drivers/mmc/core/block.c | 49 ++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 43 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 91e1e93..b8fa62c 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -1369,12 +1369,46 @@ static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
R1_CC_ERROR | /* Card controller error */ \
R1_ERROR) /* General/unknown error */
-static bool mmc_blk_has_cmd_err(struct mmc_command *cmd)
+static void mmc_blk_eval_resp_error(struct mmc_blk_request *brq)
{
- if (!cmd->error && cmd->resp[0] & CMD_ERRORS)
- cmd->error = -EIO;
+ u32 val;
- return cmd->error;
+ /*
+ * Per the SD specification(physical layer version 4.10)[1],
+ * section 4.3.3, it explicitly states that "When the last
+ * block of user area is read using CMD18, the host should
+ * ignore OUT_OF_RANGE error that may occur even the sequence
+ * is correct". And JESD84-B51 for eMMC also has a similar
+ * statement on section 6.8.3.
+ *
+ * Multiple block read/write could be done by either predefined
+ * method, namely CMD23, or open-ending mode. For open-ending mode,
+ * we should ignore the OUT_OF_RANGE error as it's normal behaviour.
+ *
+ * However the spec[1] doesn't tell us whether we should also
+ * ignore that for predefined method. But per the spec[1], section
+ * 4.15 Set Block Count Command, it says"If illegal block count
+ * is set, out of range error will be indicated during read/write
+ * operation (For example, data transfer is stopped at user area
+ * boundary)." In another word, we could expect a out of range error
+ * in the response for the following CMD18/25. And if argument of
+ * CMD23 + the argument of CMD18/25 exceed the max number of blocks,
+ * we could also expect to get a -ETIMEDOUT or any error number from
+ * the host drivers due to missing data response(for write)/data(for
+ * read), as the cards will stop the data transfer by itself per the
+ * spec. So we only need to check R1_OUT_OF_RANGE for open-ending mode.
+ */
+
+ if (!brq->stop.error) {
+ bool oor_with_open_end;
+ /* If there is no error yet, check R1 response */
+
+ val = brq->stop.resp[0] & CMD_ERRORS;
+ oor_with_open_end = val & R1_OUT_OF_RANGE && !brq->mrq.sbc;
+
+ if (val && !oor_with_open_end)
+ brq->stop.error = -EIO;
+ }
}
static enum mmc_blk_status mmc_blk_err_check(struct mmc_card *card,
@@ -1398,8 +1432,11 @@ static enum mmc_blk_status mmc_blk_err_check(struct mmc_card *card,
* stop.error indicates a problem with the stop command. Data
* may have been transferred, or may still be transferring.
*/
- if (brq->sbc.error || brq->cmd.error || mmc_blk_has_cmd_err(&brq->stop) ||
- brq->data.error) {
+
+ mmc_blk_eval_resp_error(brq);
+
+ if (brq->sbc.error || brq->cmd.error ||
+ brq->stop.error || brq->data.error) {
switch (mmc_blk_cmd_recovery(card, req, brq, &ecc_err, &gen_err)) {
case ERR_RETRY:
return MMC_BLK_RETRY;
--
1.9.1
--
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