[PATCH] ARM: dts: exynos: Properly select eMMC HighSpeed mode

Krzysztof Kozlowski k.kozlowski at samsung.com
Thu Jul 14 05:47:38 PDT 2016


Exynos5410 supports eMMC version 4.41 so HS200 is the top mode which
should be configured.  This is reflected in usage of
"samsung,exynos5250-dw-mshc" compatible.  However DTS contained also
property "mmc-hs400-1_8v" which is parsed by MMC core therefore
resulting in mixed configuration.  MMC core set HS400 but dwmmc_exynos
driver did not configure the data strobe for HS400 DDR mode.

Removal of HS400 properties fixes semi-random mmc errors during boot:
  mmc_host mmc0: Bus speed (slot 0) = 400000000Hz (slot req 200000000Hz, actual 200000000HZ div = 1)
  mmc0: mmc_select_hs400 failed, error -84
  mmc0: error -84 whilst initialising MMC card

Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
---
 arch/arm/boot/dts/exynos5410-odroidxu.dts | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/arm/boot/dts/exynos5410-odroidxu.dts b/arch/arm/boot/dts/exynos5410-odroidxu.dts
index d9499310a301..7536164438ca 100644
--- a/arch/arm/boot/dts/exynos5410-odroidxu.dts
+++ b/arch/arm/boot/dts/exynos5410-odroidxu.dts
@@ -447,14 +447,12 @@
 	samsung,dw-mshc-ciu-div = <3>;
 	samsung,dw-mshc-sdr-timing = <0 4>;
 	samsung,dw-mshc-ddr-timing = <0 2>;
-	samsung,dw-mshc-hs400-timing = <0 2>;
 	samsung,read-strobe-delay = <90>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&sd0_clk &sd0_cmd &sd0_bus1 &sd0_bus4 &sd0_bus8 &sd0_cd>;
 	bus-width = <8>;
 	cap-mmc-highspeed;
 	mmc-hs200-1_8v;
-	mmc-hs400-1_8v;
 	vmmc-supply = <&ldo20_reg>;
 	vqmmc-supply = <&ldo11_reg>;
 };
-- 
1.9.1




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