ARM: dts: Add devicetree for OrangePi 2G IoT board

Add initial devicetree support for OrangePi 2G IoT board from Xunlong.

Signed-off-by: Andreas Färber <[e-mail]>
Signed-off-by: Manivannan Sadhasivam <[e-mail]>
Acked-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Olof Johansson <[e-mail]>

arch/arm/boot/dts/Makefile

···
 	qcom-msm8974-sony-xperia-castor.dtb \
 	qcom-msm8974-sony-xperia-honami.dtb \
 	qcom-mdm9615-wp8548-mangoh-green.dtb
+dtb-$(CONFIG_ARCH_RDA) += \
+	rda8810pl-orangepi-2g-iot.dtb
 dtb-$(CONFIG_ARCH_REALVIEW) += \
 	arm-realview-pb1176.dtb \
 	arm-realview-pb11mp.dtb \

arch/arm/boot/dts/rda8810pl-orangepi-2g-iot.dts

···
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2017 Andreas Färber
+ * Copyright (c) 2018 Manivannan Sadhasivam
+ */
+
+/dts-v1/;
+
+#include "rda8810pl.dtsi"
+
+/ {
+	compatible = "xunlong,orangepi-2g-iot", "rda,8810pl";
+	model = "Orange Pi 2G-IoT";
+
+	aliases {
+		serial0 = &uart1;
+		serial1 = &uart2;
+		serial2 = &uart3;
+	};
+
+	chosen {
+		stdout-path = "serial2:921600n8";
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x80000000 0x10000000>;
+	};
+
+	uart_clk: uart-clk {
+		compatible = "fixed-clock";
+		clock-frequency = <921600>;
+		#clock-cells = <0>;
+	};
+};
+
+&uart1 {
+	status = "okay";
+	clocks = <&uart_clk>;
+};
+
+&uart2 {
+	status = "okay";
+	clocks = <&uart_clk>;
+};
+
+&uart3 {
+	status = "okay";
+	clocks = <&uart_clk>;
+};