Re: [PATCH 2/3] arm64: dts: sophgo: add initial Milk-V Duo S board support

On Fri, Oct 10, 2025 at 09:48:10PM -0400, Joshua Milas wrote:
> This adds initial arm64 support for the Milk-V Duo S board
> [1] making it possible to boot Linux to the command line.
> 
> Link: https://milkv.io/duo-s [1]
> 
> Signed-off-by: Joshua Milas <[email protected]>
> ---
>  arch/arm64/boot/dts/sophgo/Makefile           |   1 +
>  .../boot/dts/sophgo/sg2000-milkv-duo-s.dts    | 110 ++++++++++++++++++
>  2 files changed, 111 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..e9afad6fd106
> --- /dev/null
> +++ b/arch/arm64/boot/dts/sophgo/sg2000-milkv-duo-s.dts
> @@ -0,0 +1,110 @@
> +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> +
> +/dts-v1/;
> +
> +#include <dt-bindings/pinctrl/pinctrl-sg2000.h>
> +#include "sg2000.dtsi"
> +
> +/ {
> +	model = "Milk-V Duo S";
> +	compatible = "milkv,duo-s", "sophgo,sg2000";
> +
> +	aliases {
> +		mmc0 = &sdhci0;
> +		serial0 = &uart0;
> +		serial1 = &uart1;
> +		serial2 = &uart2;
> +		serial3 = &uart3;
> +	};
> +
> +	chosen {
> +		stdout-path = "serial0:115200n8";
> +	};
> +};
> +
> +&osc {
> +	clock-frequency = <25000000>;
> +};
> +
> +&dmac {
> +	status = "okay";
> +};
> +
> +&emmc {
> +	bus-width = <4>;
> +	no-1-8-v;
> +	cap-mmc-hw-reset;
> +	no-sd;
> +	no-sdio;
> +	non-removable;
> +	status = "okay";
> +};
> +
> +&gmac0 {
> +	status = "okay";
> +};
> +
> +&i2c1 {
> +	status = "okay";
> +};
> +
> +&i2c2 {
> +	status = "okay";
> +};
> +
> +&i2c3 {
> +	status = "okay";
> +};
> +
> +&i2c4 {
> +	status = "okay";
> +};
> +
> +&mdio {
> +	status = "okay";
> +};
> +
> +&saradc {
> +	status = "okay";
> +};
> +
> +&sdhci0 {
> +	bus-width = <4>;
> +	no-1-8-v;
> +	disable-wp;
> +	status = "okay";
> +};
> +
> +&sdhci1 {
> +	bus-width = <4>;
> +	cap-sdio-irq;
> +	no-mmc;
> +	no-sd;
> +	non-removable;
> +	status = "okay";
> +};
> +
> +&spi0 {
> +	status = "okay";
> +};
> +
> +&spi3 {
> +	status = "okay";
> +};
> +
> +&uart0 {
> +	status = "okay";
> +};
> +
> +&uart1 {
> +	status = "okay";
> +};
> +
> +&uart2 {
> +	status = "okay";
> +};
> +
> +&uart3 {
> +	status = "okay";
> +};
> +
> -- 
> 2.51.0
> 

Only enable device that can be accessed directly. These devices share
some pins and only one of them can be used. I suggest enabling devices
that are accessed by default (which means it is compatible with the
vendor kernel).

This advice also applys to the riscv dts.

Regards,
Inochi