Jisheng Zhang 071b3300c9 mmc: sdhci: Use Auto CMD Auto Select only when v4_mode is true ... commit b3e1ea16fb upstream. sdhci-of-dwcmshc meets an eMMC read performance regression with below command after commit 427b6514d0 ("mmc: sdhci: Add Auto CMD Auto Select support"): dd if=/dev/mmcblk0 of=/dev/null bs=8192 count=100000 Before the commit, the above command gives 120MB/s After the commit, the above command gives 51.3 MB/s So it looks like sdhci-of-dwcmshc expects Version 4 Mode for Auto CMD Auto Select. Fix the performance degradation by ensuring v4_mode is true to use Auto CMD Auto Select. Fixes: 427b6514d0 ("mmc: sdhci: Add Auto CMD Auto Select support") Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201015174115.4cf2c19a@xhacker.debian Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-11-05 11:43:36 +01:00
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core	mmc: sdio: Check for CISTPL_VERS_1 buffer size	2020-10-29 09:58:03 +01:00
host	mmc: sdhci: Use Auto CMD Auto Select only when v4_mode is true	2020-11-05 11:43:36 +01:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00