Re: [PATCH 2/2] arm64: dts: sophgo: add initial Milk-V Duo S board support

On Sat, Sep 27, 2025 at 01:36:19PM -0400, Joshua Milas wrote:
> This adds initial arm64 support for the Milk-V Duo S board
> (https://milkv.io/duo-s), enabling the serial port and sdhci0,
> making it possible to boot Linux to the command line.
> 
> Signed-off-by: Joshua Milas <[email protected]>
> ---
>  arch/arm64/boot/dts/sophgo/Makefile           |  1 +
>  .../boot/dts/sophgo/sg2000-milkv-duo-s.dts    | 88 +++++++++++++++++++
>  2 files changed, 89 insertions(+)
>  create mode 100644 arch/arm64/boot/dts/sophgo/sg2000-milkv-duo-s.dts
> 
> diff --git a/arch/arm64/boot/dts/sophgo/Makefile b/arch/arm64/boot/dts/sophgo/Makefile
> index 94f52cd7d994..68aace728223 100644
> --- a/arch/arm64/boot/dts/sophgo/Makefile
> +++ b/arch/arm64/boot/dts/sophgo/Makefile
> @@ -1,2 +1,3 @@
>  # SPDX-License-Identifier: GPL-2.0
>  dtb-$(CONFIG_ARCH_SOPHGO) += sg2000-milkv-duo-module-01-evb.dtb
> +dtb-$(CONFIG_ARCH_SOPHGO) += sg2000-milkv-duo-s.dtb
> diff --git a/arch/arm64/boot/dts/sophgo/sg2000-milkv-duo-s.dts b/arch/arm64/boot/dts/sophgo/sg2000-milkv-duo-s.dts
> new file mode 100644
> index 000000000000..94cf89d423de
> --- /dev/null
> +++ b/arch/arm64/boot/dts/sophgo/sg2000-milkv-duo-s.dts
> @@ -0,0 +1,88 @@
> +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> +
> +/dts-v1/;
> +
> +#include <dt-bindings/pinctrl/pinctrl-sg2000.h>
> +#include "sg2000.dtsi"
> +
> +/ {
> +	model = "Milk-V DuoS";
> +	compatible = "milkv,duo-s", "sophgo,sg2000";
> +
> +	aliases {
> +		serial0 = &uart0;
> +		mmc0 = &sdhci0;
> +	};

It is better for adding gpio and other serial there?

> +
> +	chosen {
> +		stdout-path = "serial0:115200n8";
> +	};
> +};
> +
> +&osc {
> +	clock-frequency = <25000000>;
> +};
> +

> +&pinctrl {
> +	sdhci0_cfg: sdhci0-cfg {
> +		sdhci0-cd-pins {
> +			pinmux = <PINMUX(PIN_SD0_CD, 0)>;
> +			bias-pull-up;
> +			drive-strength-microamp = <10800>;
> +			power-source = <3300>;
> +		};
> +
> +		sdhci0-clk-pins {
> +			pinmux = <PINMUX(PIN_SD0_CLK, 0)>;
> +			bias-pull-up;
> +			drive-strength-microamp = <16100>;
> +			power-source = <3300>;
> +		};
> +
> +		sdhci0-cmd-pins {
> +			pinmux = <PINMUX(PIN_SD0_CMD, 0)>;
> +			bias-pull-up;
> +			drive-strength-microamp = <10800>;
> +			power-source = <3300>;
> +		};
> +
> +		sdhci0-data-pins {
> +			pinmux = <PINMUX(PIN_SD0_D0, 0)>,
> +				 <PINMUX(PIN_SD0_D1, 0)>,
> +				 <PINMUX(PIN_SD0_D2, 0)>,
> +				 <PINMUX(PIN_SD0_D3, 0)>;
> +			bias-pull-up;
> +			drive-strength-microamp = <10800>;
> +			power-source = <3300>;
> +		};
> +	};
> +
> +	uart0_cfg: uart0-cfg {
> +		uart0-pins {
> +			pinmux = <PINMUX(PIN_UART0_TX, 0)>,
> +				 <PINMUX(PIN_UART0_RX, 0)>;
> +			bias-pull-up;
> +			drive-strength-microamp = <10800>;
> +			power-source = <3300>;
> +		};
> +	};
> +};

Small suggestion: please ensure the pinctrl is correct, different
board may require different configuration.

> +
> +&uart0 {
> +	pinctrl-0 = <&uart0_cfg>;
> +	pinctrl-names = "default";
> +	status = "okay";
> +	/delete-property/ resets;
> +};
> +
> +&sdhci0 {
> +	bus-width = <4>;
> +	no-1-8-v;
> +	no-mmc;
> +	no-sdio;
> +	disable-wp;
> +	pinctrl-0 = <&sdhci0_cfg>;
> +	pinctrl-names = "default";
> +	status = "okay";
> +};
> +
> -- 
> 2.51.0
> 

I suggest adding all the support devices instead of a minimum one.
Like ethernet, wifi, bluetooth.
In the next cycle, there should be a patch for adding USB device node,
as the driver is already merged. I also hope you can take it.

Regards,
Inochi