[PATCH] riscv: dts: sophgo: add initial Milk-V Duo S board device tree

[michael.opdenacker at bootlin.com]

From: Michael Opdenacker <michael.opdenacker at bootlin.com>

This adds initial support for the Milk-V Duo S board
(https://milkv.io/duo-s), enabling the serial port and
read-only SD card support, allowing to boot Linux to the
command line.

Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>

---

Tested with linux-next as of Apr 9, 2024,
using the risc-v "defconfig" configuration.
---
 arch/riscv/boot/dts/sophgo/Makefile           |  1 +
 .../boot/dts/sophgo/sg2000-milkv-duos.dts     | 38 +++++++++++++++++++
 2 files changed, 39 insertions(+)
 create mode 100644 arch/riscv/boot/dts/sophgo/sg2000-milkv-duos.dts

diff --git a/arch/riscv/boot/dts/sophgo/Makefile b/arch/riscv/boot/dts/sophgo/Makefile
index 57ad82a61ea6..e008acb5240f 100644
--- a/arch/riscv/boot/dts/sophgo/Makefile
+++ b/arch/riscv/boot/dts/sophgo/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 dtb-$(CONFIG_ARCH_SOPHGO) += cv1800b-milkv-duo.dtb
 dtb-$(CONFIG_ARCH_SOPHGO) += cv1812h-huashan-pi.dtb
+dtb-$(CONFIG_ARCH_SOPHGO) += sg2000-milkv-duos.dtb
 dtb-$(CONFIG_ARCH_SOPHGO) += sg2042-milkv-pioneer.dtb
diff --git a/arch/riscv/boot/dts/sophgo/sg2000-milkv-duos.dts b/arch/riscv/boot/dts/sophgo/sg2000-milkv-duos.dts
new file mode 100644
index 000000000000..cf2cec3cc369
--- /dev/null
+++ b/arch/riscv/boot/dts/sophgo/sg2000-milkv-duos.dts
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2024 Michael Opdenacker <michael.opdenacker at bootlin.com>
+ */
+
+/dts-v1/;
+
+#include "cv1800b.dtsi"
+
+/ {
+	model = "Milk-V Duo S";
+	compatible = "milkv,duos", "sophgo,sg2000";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory at 80000000 {
+		device_type = "memory";
+		reg = <0x80000000 0x20000000>;
+	};
+};
+
+&osc {
+	clock-frequency = <25000000>;
+};
+
+&sdhci0 {
+	status = "okay";
+};
+
+&uart0 {
+	status = "okay";
+};
-- 
2.34.1