arm64: dts: add board AN400

Add devicetrees support for Amlogic AN400  board based T7 SoC.
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Link: https://lore.kernel.org/r/20230706091954.3301224-3-xianwei.zhao@amlogic.comSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>

arch/arm64/boot/dts/amlogic/Makefile

 # SPDX-License-Identifier: GPL-2.0
 dtb-$(CONFIG_ARCH_MESON) += amlogic-c3-c302x-aw409.dtb
+dtb-$(CONFIG_ARCH_MESON) += amlogic-t7-a311d2-an400.dtb
 dtb-$(CONFIG_ARCH_MESON) += amlogic-t7-a311d2-khadas-vim4.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-a1-ad401.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-axg-jethome-jethub-j100.dtb

arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts

+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2023 Amlogic, Inc. All rights reserved.
+ */
+
+/dts-v1/;
+
+#include "amlogic-t7.dtsi"
+
+/ {
+	model = "Amlogic A311D2 AN400 Development Board";
+	compatible = "amlogic,an400", "amlogic,a311d2", "amlogic,t7";
+	interrupt-parent = <&gic>;
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	aliases {
+		serial0 = &uart_a;
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x00000000 0x00000000 0xE0000000
+			0x00000001 0x00000000 0x00000000 0x20000000>;
+	};
+
+	xtal: xtal-clk {
+		compatible = "fixed-clock";
+		clock-frequency = <24000000>;
+		clock-output-names = "xtal";
+		#clock-cells = <0>;
+	};
+};
+
+&uart_a {
+	clocks = <&xtal>, <&xtal>, <&xtal>;
+	clock-names = "xtal", "pclk", "baud";
+	status = "okay";
+};