arm64: dts: broadcom: add BCM4908 and Asus GT-AC5300 early DTS files

They don't descibe hardware fully yet but it's enough to boot a system.

Some missing blocks:
1. PMC (Power Management Controller?)
2. Ethernet
3. Crypto
4. Thermal

Asus DTS is missing defining full NAND partitions layout and buttons.

Further changes will fill those gaps as soon as required bindings will
be found / tested / added.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm64/boot/dts/broadcom/Makefile

@@ -5,5 +5,6 @@ dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-4-b.dtb \
 			      bcm2837-rpi-3-b-plus.dtb \
 			      bcm2837-rpi-cm3-io3.dtb
 
+subdir-y	+= bcm4908
 subdir-y	+= northstar2
 subdir-y	+= stingray

arch/arm64/boot/dts/broadcom/bcm4908/Makefile

+# SPDX-License-Identifier: GPL-2.0
+dtb-$(CONFIG_ARCH_BCM4908) += bcm4908-asus-gt-ac5300.dtb

arch/arm64/boot/dts/broadcom/bcm4908/bcm4908-asus-gt-ac5300.dts

+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+#include "bcm4908.dtsi"
+
+/ {
+	compatible = "asus,gt-ac5300", "brcm,bcm4908";
+	model = "Asus GT-AC5300";
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00 0x00 0x00 0x40000000>;
+	};
+
+	gpio-keys-polled {
+		compatible = "gpio-keys-polled";
+		poll-interval = <100>;
+
+		wifi {
+			label = "WiFi";
+			linux,code = <KEY_RFKILL>;
+			gpios = <&gpio0 28 GPIO_ACTIVE_LOW>;
+		};
+
+		wps {
+			label = "WPS";
+			linux,code = <KEY_WPS_BUTTON>;
+			gpios = <&gpio0 29 GPIO_ACTIVE_LOW>;
+		};
+
+		restart {
+			label = "Reset";
+			linux,code = <KEY_RESTART>;
+			gpios = <&gpio0 30 GPIO_ACTIVE_LOW>;
+		};
+
+		brightness {
+			label = "LEDs";
+			linux,code = <KEY_BRIGHTNESS_ZERO>;
+			gpios = <&gpio0 31 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&nandcs {
+	nand-ecc-strength = <4>;
+	nand-ecc-step-size = <512>;
+	nand-on-flash-bbt;
+	brcm,nand-has-wp;
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		partition@0 {
+			label = "cferom";
+			reg = <0x0 0x100000>;
+		};
+	};
+};

arch/arm64/boot/dts/broadcom/bcm4908/bcm4908.dtsi

+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+/dts-v1/;
+
+/ {
+	interrupt-parent = <&gic>;
+
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu0: cpu@0 {
+			device_type = "cpu";
+			compatible = "brcm,brahma-b53";
+			reg = <0x0>;
+			next-level-cache = <&l2>;
+		};
+
+		cpu1: cpu@1 {
+			device_type = "cpu";
+			compatible = "brcm,brahma-b53";
+			reg = <0x1>;
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0xfff8>;
+			next-level-cache = <&l2>;
+		};
+
+		cpu2: cpu@2 {
+			device_type = "cpu";
+			compatible = "brcm,brahma-b53";
+			reg = <0x2>;
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0xfff8>;
+			next-level-cache = <&l2>;
+		};
+
+		cpu3: cpu@3 {
+			device_type = "cpu";
+			compatible = "brcm,brahma-b53";
+			reg = <0x3>;
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0xfff8>;
+			next-level-cache = <&l2>;
+		};
+
+		l2: l2-cache0 {
+			compatible = "cache";
+		};
+	};
+
+	axi@81000000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x00 0x00 0x81000000 0x4000>;
+
+		gic: interrupt-controller@1000 {
+			compatible = "arm,gic-400";
+			#interrupt-cells = <3>;
+			#address-cells = <0>;
+			interrupt-controller;
+			reg = <0x1000 0x1000>,
+			      <0x2000 0x2000>;
+		};
+	};
+
+	timer {
+		compatible = "arm,armv8-timer";
+		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
+	};
+
+	pmu {
+		compatible = "arm,cortex-a53-pmu";
+		interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>,
+			     <GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>,
+			     <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
+			     <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-affinity = <&cpu0>, <&cpu1>, <&cpu2>, <&cpu3>;
+	};
+
+	clocks {
+		periph_clk: periph_clk {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			clock-frequency = <50000000>;
+			clock-output-names = "periph";
+		};
+	};
+
+	soc {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x00 0x00 0x80000000 0x10000>;
+
+		usb@c300 {
+			compatible = "generic-ehci";
+			reg = <0xc300 0x100>;
+			interrupts = <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+		};
+
+		usb@c400 {
+			compatible = "generic-ohci";
+			reg = <0xc400 0x100>;
+			interrupts = <GIC_SPI 72 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+		};
+
+		usb@d000 {
+			compatible = "generic-xhci";
+			reg = <0xd000 0x8c8>;
+			interrupts = <GIC_SPI 74 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+		};
+	};
+
+	bus@ff800000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x00 0x00 0xff800000 0x3000>;
+
+		timer: timer@400 {
+			compatible = "brcm,bcm6328-timer", "syscon";
+			reg = <0x400 0x3c>;
+		};
+
+		gpio0: gpio-controller@500 {
+			compatible = "brcm,bcm6345-gpio";
+			reg-names = "dirout", "dat";
+			reg = <0x500 0x28>, <0x528 0x28>;
+
+			#gpio-cells = <2>;
+			gpio-controller;
+		};
+
+		uart0: serial@640 {
+			compatible = "brcm,bcm6345-uart";
+			reg = <0x640 0x18>;
+			interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&periph_clk>;
+			clock-names = "periph";
+			status = "okay";
+		};
+
+		nand@1800 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "brcm,brcmnand-v7.1", "brcm,brcmnand";
+			reg = <0x1800 0x600>, <0x2000 0x10>;
+			reg-names = "nand", "nand-int-base";
+			interrupts = <GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "nand";
+			status = "okay";
+
+			nandcs: nandcs@0 {
+				compatible = "brcm,nandcs";
+				reg = <0>;
+			};
+		};
+
+		reboot {
+			compatible = "syscon-reboot";
+			regmap = <&timer>;
+			offset = <0x34>;
+			mask = <1>;
+		};
+	};
+};