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[5.4,031/340] arm64: dts: allwinner: H6: Allow up to 150 MHz MMC bus frequency

Message ID 20210301161049.842195616@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH March 1, 2021, 4:09 p.m. UTC 
From: Andre Przywara <andre.przywara@arm.com>

[ Upstream commit cfe6c487b9a1abc6197714ec5605716a5428cf03 ]

The H6 manual explicitly lists a frequency limit of 150 MHz for the bus
frequency of the MMC controllers. So far we had no explicit limits in the
DT, which limited eMMC to the spec defined frequencies, or whatever the
driver defines (both Linux and FreeBSD use 52 MHz here).

Put those maximum frequencies in the SoC .dtsi, to allow higher speed
modes (which still would need to be explicitly enabled, per board).

Tested with an eMMC using HS-200 on a Pine H64. Running at the spec'ed
200 MHz indeed fails with I/O errors, but 150 MHz seems to work stably.

Fixes: 8f54bd1595b3 ("arm64: allwinner: h6: add device tree nodes for MMC controllers")
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20210113152630.28810-6-andre.przywara@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
index 8b77bd5a3c017..1583cd5915214 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
+++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
@@ -332,6 +332,7 @@ 
 			interrupts = <GIC_SPI 35 IRQ_TYPE_LEVEL_HIGH>;
 			pinctrl-names = "default";
 			pinctrl-0 = <&mmc0_pins>;
+			max-frequency = <150000000>;
 			status = "disabled";
 			#address-cells = <1>;
 			#size-cells = <0>;
@@ -348,6 +349,7 @@ 
 			interrupts = <GIC_SPI 36 IRQ_TYPE_LEVEL_HIGH>;
 			pinctrl-names = "default";
 			pinctrl-0 = <&mmc1_pins>;
+			max-frequency = <150000000>;
 			status = "disabled";
 			#address-cells = <1>;
 			#size-cells = <0>;
@@ -364,6 +366,7 @@ 
 			interrupts = <GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>;
 			pinctrl-names = "default";
 			pinctrl-0 = <&mmc2_pins>;
+			max-frequency = <150000000>;
 			status = "disabled";
 			#address-cells = <1>;
 			#size-cells = <0>;