arm64: dts: allwinner: H6: Allow up to 150 MHz MMC bus frequency

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

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
index f593cfeaecc9f7017a0f4bfb80809d382cc75846..77765d4a05ec9b5974ba39e2a6715deed6a6166e 100644 (file)
--- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
+++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
@@ -436,6 +436,7 @@
                        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>;
@@ -452,6 +453,7 @@
                        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>;
@@ -468,6 +470,7 @@
                        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>;