Re: [PATCH v2] ARM: dts: exynos: Properly select eMMC HighSpeed mode on Odroid XU

From: Alim Akhtar
Date: Fri Jul 15 2016 - 05:01:39 EST




On 07/15/2016 01:42 PM, Krzysztof Kozlowski wrote:
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 Odroid XU 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@xxxxxxxxxxx>

Looks good, thanks.

Reviewed-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>

---

Changes since v1:
1. Remove also samsung,read-strobe-delay, suggested by Alim Akhtar.
---
arch/arm/boot/dts/exynos5410-odroidxu.dts | 3 ---
1 file changed, 3 deletions(-)

diff --git a/arch/arm/boot/dts/exynos5410-odroidxu.dts b/arch/arm/boot/dts/exynos5410-odroidxu.dts
index d9499310a301..f6d135245a4b 100644
--- a/arch/arm/boot/dts/exynos5410-odroidxu.dts
+++ b/arch/arm/boot/dts/exynos5410-odroidxu.dts
@@ -447,14 +447,11 @@
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>;
};