From d83c2dbaa90a9bd6346e234d9802080a9c7b2fea Mon Sep 17 00:00:00 2001 From: Shawn Lin Date: Fri, 18 Aug 2017 09:16:08 +0800 Subject: [PATCH] mmc: block: prevent propagating R1_OUT_OF_RANGE for open-ending mode 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 Reviewed-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: Ulf Hansson --- 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 f1bbfd389367..80d1ec693d2d 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -1371,12 +1371,46 @@ 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, @@ -1400,8 +1434,11 @@ 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; -- 2.45.2