Add Milk-V Duo board support

Add initial device tree for the CV1800B RISC-V SoC by SOPHGO.

Signed-off-by Jisheng Zhang <[email protected]>

---
  arch/riscv/boot/dts/sophgo/cv1800b.dtsi | 123 ++++++++++++++++++++++++
  1 file changed, 123 insertions(+)

create mode 100644 arch/riscv/boot/dts/sophgo/cv1800b.dtsi

arch/riscv/boot/dts/sophgo/cv1800b.dtsi new file +123 -0

new file mode 100644
index 000000000000..df40e87ee063
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2023 Jisheng Zhang <[email protected]>
+ */
+
+#include <dt-bindings/interrupt-controller/irq.h>
+
+/ {
+	compatible = "sophgo,cv1800b";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	cpus: cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		timebase-frequency = <25000000>;
+
+		cpu0: cpu@0 {
+			compatible = "thead,c906", "riscv";
+			device_type = "cpu";
+			reg = <0>;
+			d-cache-block-size = <64>;
+			d-cache-sets = <512>;
+			d-cache-size = <65536>;
+			i-cache-block-size = <64>;
+			i-cache-sets = <128>;
+			i-cache-size = <32768>;
+			mmu-type = "riscv,sv39";
+			riscv,isa = "rv64imafdc";
+			riscv,isa-base = "rv64i";
+			riscv,isa-extensions = "i", "m", "a", "f", "d", "c", "zicntr", "zicsr",
+					       "zifencei", "zihpm";
+
+			cpu0_intc: interrupt-controller {
+				compatible = "riscv,cpu-intc";
+				interrupt-controller;
+				#address-cells = <0>;
+				#interrupt-cells = <1>;
+			};
+		};
+	};
+
+	osc: oscillator {
+		compatible = "fixed-clock";
+		clock-output-names = "osc_25m";
+		#clock-cells = <0>;
+	};
+
+	soc {
+		compatible = "simple-bus";
+		interrupt-parent = <&plic>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		dma-noncoherent;
+		ranges;
+
+		uart0: serial@4140000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x04140000 0x100>;
+			interrupts = <44 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&osc>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+			status = "disabled";
+		};
+
+		uart1: serial@4150000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x04150000 0x100>;
+			interrupts = <45 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&osc>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+			status = "disabled";
+		};
+
+		uart2: serial@4160000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x04160000 0x100>;
+			interrupts = <46 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&osc>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+			status = "disabled";
+		};
+
+		uart3: serial@4170000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x04170000 0x100>;
+			interrupts = <47 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&osc>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+			status = "disabled";
+		};
+
+		uart4: serial@41c0000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x041c0000 0x100>;
+			interrupts = <48 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&osc>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+			status = "disabled";
+		};
+
+		plic: interrupt-controller@70000000 {
+			compatible = "sophgo,cv1800b-plic", "thead,c900-plic";
+			reg = <0x70000000 0x4000000>;
+			interrupts-extended = <&cpu0_intc 11>, <&cpu0_intc 9>;
+			interrupt-controller;
+			#address-cells = <0>;
+			#interrupt-cells = <2>;
+			riscv,ndev = <101>;
+		};
+
+		clint: timer@74000000 {
+			compatible = "sophgo,cv1800b-clint", "thead,c900-clint";
+			reg = <0x74000000 0x10000>;
+			interrupts-extended = <&cpu0_intc 3>, <&cpu0_intc 7>;
+		};
+	};
+};

Milk-V Duo[1] board is an embedded development platform based on the CV1800B chip. Add minimal device tree files for the development board.

Support basic uart drivers, so supports booting to a basic shell.

Link https://milkv.io/duo [1]

Signed-off-by Jisheng Zhang <[email protected]>

---
  arch/riscv/boot/dts/sophgo/Makefile           |  2 +-
  .../boot/dts/sophgo/cv1800b-milkv-duo.dts     | 38 +++++++++++++++++++
  2 files changed, 39 insertions(+), 1 deletion(-)

create mode 100644 arch/riscv/boot/dts/sophgo/cv1800b-milkv-duo.dts

arch/riscv/boot/dts/sophgo/Makefile +1 -1

index 5a471b19df22..3fb65512c631 100644
@@ -1,3 +1,3 @@
  # SPDX-License-Identifier: GPL-2.0
+dtb-$(CONFIG_ARCH_SOPHGO) += cv1800b-milkv-duo.dtb
  dtb-$(CONFIG_ARCH_SOPHGO) += sg2042-milkv-pioneer.dtb
-

arch/riscv/boot/dts/sophgo/cv1800b-milkv-duo.dts new file +38 -0

new file mode 100644
index 000000000000..3af9e34b3bc7
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2023 Jisheng Zhang <[email protected]>
+ */
+
+/dts-v1/;
+
+#include "cv1800b.dtsi"
+
+/ {
+	model = "Milk-V Duo";
+	compatible = "milkv,duo", "sophgo,cv1800b";
+
+	aliases {
+		serial0 = &uart0;
+		serial1 = &uart1;
+		serial2 = &uart2;
+		serial3 = &uart3;
+		serial4 = &uart4;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x80000000 0x3f40000>;
+	};
+};
+
+&osc {
+	clock-frequency = <25000000>;
+};
+
+&uart0 {
+	status = "okay";
+};

Milk-V Duo[1] board is an embedded development platform based on the CV1800B[2] chip. Add minimal device tree files for the development board. Currently, now it's supported to boot to a basic shell.

NOTE: this series is based on the SG2042 upstream series[3] for the vendor prefix and ARCH_SOPHGO option.

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