From: Martin Blumenstingl martin.blumenstingl@googlemail.com
[ Upstream commit 91995b904ec2e44b5c159ac6a5d3f154345a4de7 ]
The vendor driver (from the 3.10 kernel) triggers a soft reset every time before starting a new command. While this fixes a problem where SDIO cards are not detected at all (because all commands simply timed out) this hurts SD card read performance a bit (in my tests between 10% to 20%).
Trigger a soft reset after we got a CRC error or if the previous command timed out (just like the vendor driver from the same 3.10 kernel for the newer SDHC controller IP does). This fixes detection of SDIO cards and doesn't hurt SD card read performance at the same time.
With this patch the initialization of an RTL8723BS SDIO card looks like this: req done (CMD52): -110: 00000000 00000000 00000000 00000000 clock 400000Hz busmode 2 powermode 2 cs 1 Vdd 21 width 1 timing 0 starting CMD0 arg 00000000 flags 000000c0 req done (CMD0): 0: 00000000 00000000 00000000 00000000 clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 0 starting CMD8 arg 000001aa flags 000002f5 req done (CMD8): -110: 00000000 00000000 00000000 00000000 starting CMD5 arg 00000000 flags 000002e1 req done (CMD5): 0: 90ff0000 00000000 00000000 00000000 starting CMD5 arg 00200000 flags 000002e1 req done (CMD5): 0: 90ff0000 00000000 00000000 00000000 starting CMD3 arg 00000000 flags 00000075 req done (CMD3): 0: 00010000 00000000 00000000 00000000 starting CMD7 arg 00010000 flags 00000015 req done (CMD7): 0: 00001e00 00000000 00000000 00000000 starting CMD52 arg 00000000 flags 00000195 req done (CMD52): 0: 00001032 00000000 00000000 00000000 [... more CMD52 omitted ...] clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 2 clock 50000000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 2 starting CMD52 arg 00000e00 flags 00000195 req done (CMD52): 0: 00001000 00000000 00000000 00000000 starting CMD52 arg 80000e02 flags 00000195 req done (CMD52): 0: 00001002 00000000 00000000 00000000 clock 50000000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 4 timing 2 starting CMD52 arg 00020000 flags 00000195 req done (CMD52): 0: 00001007 00000000 00000000 00000000 [... more CMD52 omitted ...] new high speed SDIO card at address 0001
Fixes: ed80a13bb4c4c9 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs") Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com Link: https://lore.kernel.org/r/20200503222805.2668941-1-martin.blumenstingl@googl... Tested-by: Tobias Baumann 017623705678@o2online.de Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/host/meson-mx-sdio.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/mmc/host/meson-mx-sdio.c b/drivers/mmc/host/meson-mx-sdio.c index 999214e8cf2b..360d523132bd 100644 --- a/drivers/mmc/host/meson-mx-sdio.c +++ b/drivers/mmc/host/meson-mx-sdio.c @@ -246,6 +246,9 @@ static void meson_mx_mmc_request_done(struct meson_mx_mmc_host *host)
mrq = host->mrq;
+ if (host->cmd->error) + meson_mx_mmc_soft_reset(host); + host->mrq = NULL; host->cmd = NULL;