On 15/05/2017 05:28, Simon Glass wrote:
On 12 May 2017 at 12:16, Jean-Jacques Hiblot jjhiblot@ti.com wrote:
From: Vignesh R vigneshr@ti.com
With certain SD cards like Kingston 8GB/16GB UHS card, it is seen that MMC_CMD_ALL_SEND_CID cmd fails on first attempt, but succeeds subsequently. Therefore, retry MMC_CMD_ALL_SEND_CID cmd at least thrice as done in Linux kernel. Similarly, it is seen that MMC_CMD_SET_BLOCKLEN may fail on first attempt, therefore retry this cmd five times as done in kernel.
Signed-off-by: Vignesh R vigneshr@ti.com Signed-off-by: Kishon Vijay Abraham I kishon@ti.com Signed-off-by: Jean-Jacques Hiblot jjhiblot@ti.com
drivers/mmc/mmc.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
So sad to see this sort of thing.
Can we enable this via a quirk and a Kconfig? Could default to on, but I'm not sure we want this code in regardless.
Reviewed-by: Simon Glass sjg@chromium.org
I admit that it's ugly... no clean code survives contact with a few hundred different hardware parts. We could add KConfig options to enable/disable those quirks but I don't see the point of being able to. It's just a basic retry that has no impact on things that work well already and might make other work more reliably.
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index c7dda64..49edf52 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -275,6 +275,8 @@ int mmc_send_status(struct mmc *mmc, int timeout) int mmc_set_blocklen(struct mmc *mmc, int len) { struct mmc_cmd cmd;
int retries = 5;int err; if (mmc->ddr_mode) return 0;@@ -282,8 +284,13 @@ int mmc_set_blocklen(struct mmc *mmc, int len) cmd.cmdidx = MMC_CMD_SET_BLOCKLEN; cmd.resp_type = MMC_RSP_R1; cmd.cmdarg = len;
do {err = mmc_send_cmd(mmc, &cmd, NULL);if (!err)break;} while (retries--);
return mmc_send_cmd(mmc, &cmd, NULL);
return err;}
static int mmc_read_blocks(struct mmc *mmc, void *dst, lbaint_t start,
@@ -1867,6 +1874,7 @@ static int mmc_startup(struct mmc *mmc) u64 cmult, csize; struct mmc_cmd cmd; struct blk_desc *bdesc;
int retries = 3;#ifdef CONFIG_MMC_SPI_CRC_ON if (mmc_host_is_spi(mmc)) { /* enable CRC check for spi */
@@ -1874,7 +1882,6 @@ static int mmc_startup(struct mmc *mmc) cmd.resp_type = MMC_RSP_R1; cmd.cmdarg = 1; err = mmc_send_cmd(mmc, &cmd, NULL);
if (err) return err; }@@ -1886,7 +1893,9 @@ static int mmc_startup(struct mmc *mmc) cmd.resp_type = MMC_RSP_R2; cmd.cmdarg = 0;
err = mmc_send_cmd(mmc, &cmd, NULL);
do {err = mmc_send_cmd(mmc, &cmd, NULL);} while (err && retries-- > 0); if (err) return err;-- 1.9.1