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

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;
+	};
+
+	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>;
+		};
+	};
+};
+
+&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