[PATCH 1/3] arm64: dts: rockchip: Add supported UHS-I rates to sdmmc0 on rock-3b

[Jonas Karlman]

Hi Tamás,

On 2024-11-11 19:17, Tamás Szűcs wrote:
> Add all supported UHS-I rates to sdmmc0 and allow 200 MHz maximum clock to
> benefit modern SD cards.
> 
> Signed-off-by: Tamás Szűcs <tszucs at linux.com>
> ---
>  arch/arm64/boot/dts/rockchip/rk3568-rock-3b.dts | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3568-rock-3b.dts b/arch/arm64/boot/dts/rockchip/rk3568-rock-3b.dts
> index 3d0c1ccfaa79..242af5337cdf 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3568-rock-3b.dts
> +++ b/arch/arm64/boot/dts/rockchip/rk3568-rock-3b.dts
> @@ -670,8 +670,14 @@ &sdmmc0 {
>  	bus-width = <4>;
>  	cap-sd-highspeed;
>  	disable-wp;
> +	max-frequency = <200000000>;
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&sdmmc0_bus4 &sdmmc0_clk &sdmmc0_cmd &sdmmc0_det>;
> +	sd-uhs-sdr12;
> +	sd-uhs-sdr25;
> +	sd-uhs-sdr50;
> +	sd-uhs-sdr104;
> +	sd-uhs-ddr50;

There is an issue with io-domain driver not always being probed before
mmc driver, this typically result in io-domain being configured wrong,
and mmc tuning happen before io-domain is correctly configured.

You can usually observe this by looking at the tuning value during boot
and comparing it to the tuning value after removing and re-insering a
sd-card.

Because of this uhs modes was left out from initial DT submission, some
cards will work others wont, sd-uhs-sdr50 is known to be working with
most cards even with the probe order issue.

Also I thought that lower speeds where implied?

Regards,
Jonas

>  	vmmc-supply = <&vcc3v3_sd>;
>  	vqmmc-supply = <&vccio_sd>;
>  	status = "okay";