Re: [linux-sunxi] [PATCH 1/3] arm64: dts: allwinner: a64: olinuxino: Fix eMMC supply regulator

From: Chen-Yu Tsai
Date: Fri Nov 29 2019 - 04:26:57 EST


On Fri, Nov 29, 2019 at 5:14 PM Stefan Mavrodiev <stefan@xxxxxxxxxx> wrote:
>
> A64-OLinuXino-eMMC uses 1.8V for eMMC supply. This is done via a triple
> jumper, which sets VCC-PL to either 1.8V or 3.3V. This setting is different
> for boards with and without eMMC.
>
> This is not a big issue for DDR52 mode, however the eMMC will not work in
> HS200/HS400, since these modes explicitly requires 1.8V.
>
> Signed-off-by: Stefan Mavrodiev <stefan@xxxxxxxxxx>
> ---
> arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-emmc.dts | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-emmc.dts b/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-emmc.dts
> index 96ab0227e82d..7d135decbd53 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-emmc.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-emmc.dts
> @@ -14,8 +14,8 @@
> &mmc2 {
> pinctrl-names = "default";
> pinctrl-0 = <&mmc2_pins>;
> - vmmc-supply = <&reg_dcdc1>;
> - vqmmc-supply = <&reg_dcdc1>;
> + vmmc-supply = <&reg_eldo1>;

If I'm reading the schematics correctly, VCC on the eMMC is from 3.3V.
This corresponds to the vmmc-supply property. So you shouldn't change it.

> + vqmmc-supply = <&reg_eldo1>;

vqmmc-supply is from the VCC-PC rail, which is the one you say is triple-
jumpered. So this change makes sense.

ChenYu