This is a note to let you know that I've just added the patch titled arm64: dts: allwinner: A64: Limit MMC2 bus frequency to 150 MHz to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-dts-allwinner-a64-limit-mmc2-bus-frequency-to-.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a0a0a2efd49bb90549b45f3e9806ea5562fac41b Author: Andre Przywara <andre.przywara@xxxxxxx> Date: Wed Jan 13 15:26:28 2021 +0000 arm64: dts: allwinner: A64: Limit MMC2 bus frequency to 150 MHz [ Upstream commit 948c657cc45e8ce48cb533d4e2106145fa765759 ] In contrast to the H6 (and later) manuals, the A64 datasheet does not specify any limitations in the maximum possible frequency for eMMC controllers. However experimentation has found that a 150 MHz limit similar to other SoCs and also the MMC0 and MMC1 controllers on the A64 seems to exist for the MMC2 controller. Limit the frequency for the MMC2 controller to 150 MHz in the SoC .dtsi. The Pinebook seems to be the an odd exception, since it apparently seems to work with 200 MHz as well, so overwrite this in its board .dts file. Tested on a Pine64-LTS: 200 MHz HS-200 fails, 150 MHz HS-200 works. Fixes: 22be992faea7 ("arm64: allwinner: a64: Increase the MMC max frequency") Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx> Acked-by: Chen-Yu Tsai <wens@xxxxxxxx> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210113152630.28810-7-andre.przywara@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts index b0f81802d334b..bb1de8217b86d 100644 --- a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts @@ -140,6 +140,7 @@ pinctrl-0 = <&mmc2_pins>, <&mmc2_ds_pin>; vmmc-supply = <®_dcdc1>; vqmmc-supply = <®_eldo1>; + max-frequency = <200000000>; bus-width = <8>; non-removable; cap-mmc-hw-reset; diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi index 4c85dfc811c80..cf9e3234afaf8 100644 --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi @@ -476,7 +476,7 @@ resets = <&ccu RST_BUS_MMC2>; reset-names = "ahb"; interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>; - max-frequency = <200000000>; + max-frequency = <150000000>; status = "disabled"; #address-cells = <1>; #size-cells = <0>;