diff --git a/arch/riscv/dts/Makefile b/arch/riscv/dts/Makefile
index b05bb56..17cda48 100644
--- a/arch/riscv/dts/Makefile
+++ b/arch/riscv/dts/Makefile
@@ -2,6 +2,7 @@
 
 dtb-$(CONFIG_TARGET_ANDES_AE350) += ae350_32.dtb ae350_64.dtb
 dtb-$(CONFIG_TARGET_MICROCHIP_ICICLE) += mpfs-icicle-kit.dtb
+dtb-$(CONFIG_TARGET_MILKV_DUO) += cv1800b-milkv-duo.dtb
 dtb-$(CONFIG_TARGET_QEMU_VIRT) += qemu-virt32.dtb qemu-virt64.dtb
 dtb-$(CONFIG_TARGET_OPENPITON_RISCV64) += openpiton-riscv64.dtb
 dtb-$(CONFIG_TARGET_SIFIVE_UNLEASHED) += hifive-unleashed-a00.dtb
diff --git a/arch/riscv/dts/cv1800b-milkv-duo.dts b/arch/riscv/dts/cv1800b-milkv-duo.dts
new file mode 100644
index 0000000..3af9e34
--- /dev/null
+++ b/arch/riscv/dts/cv1800b-milkv-duo.dts
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
+ */
+
+/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";
+};
diff --git a/arch/riscv/dts/cv1800b.dtsi b/arch/riscv/dts/cv1800b.dtsi
new file mode 100644
index 0000000..165e9e3
--- /dev/null
+++ b/arch/riscv/dts/cv1800b.dtsi
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
+ */
+
+#include "cv18xx.dtsi"
+
+/ {
+	compatible = "sophgo,cv1800b";
+};
+
+&plic {
+	compatible = "sophgo,cv1800b-plic", "thead,c900-plic";
+};
+
+&clint {
+	compatible = "sophgo,cv1800b-clint", "thead,c900-clint";
+};
diff --git a/arch/riscv/dts/cv18xx.dtsi b/arch/riscv/dts/cv18xx.dtsi
new file mode 100644
index 0000000..2d6f4a4
--- /dev/null
+++ b/arch/riscv/dts/cv18xx.dtsi
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
+ * Copyright (C) 2023 Inochi Amaoto <inochiama@outlook.com>
+ */
+
+#include <dt-bindings/interrupt-controller/irq.h>
+
+/ {
+	#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;
+				#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;
+
+		gpio0: gpio@3020000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3020000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			porta: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <32>;
+				reg = <0>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+				interrupts = <60 IRQ_TYPE_LEVEL_HIGH>;
+			};
+		};
+
+		gpio1: gpio@3021000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3021000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			portb: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <32>;
+				reg = <0>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+				interrupts = <61 IRQ_TYPE_LEVEL_HIGH>;
+			};
+		};
+
+		gpio2: gpio@3022000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3022000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			portc: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <32>;
+				reg = <0>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+				interrupts = <62 IRQ_TYPE_LEVEL_HIGH>;
+			};
+		};
+
+		gpio3: gpio@3023000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3023000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			portd: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <32>;
+				reg = <0>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+				interrupts = <63 IRQ_TYPE_LEVEL_HIGH>;
+			};
+		};
+
+		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 {
+			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 {
+			reg = <0x74000000 0x10000>;
+			interrupts-extended = <&cpu0_intc 3>, <&cpu0_intc 7>;
+		};
+	};
+};