ath79: add support for GL.iNet GL-XE300

The GL.iNet GL-XE300 is a 4G LTE Wireless router, based on QCA9531 SoC.

Specifications:

 - SoC: QCA9531 (650MHz)
 - RAM: DDR2 128M
 - Flash: SPI NOR 16M + SPI NAND 128M
 - WiFi: 2.4GHz with 2 antennas
 - Ethernet:
   - 1x LAN (10/100M)
   - 1x WAN (10/100M)
 - LTE:
 - USB: 1x USB 2.0 port
 - UART:
   - 3.3V, TX, RX, GND / 115200 8N1

MAC addresses as verified by OEM firmware:

 use    address   source
 LAN    *:c5      art 0x0 (label)
 WAN    *:c6      label + 1
 WLAN   *:c7      art 0x1002

Installation via U-Boot rescue:

1. Press and hold reset and power buttons simultaneously
2. Wait for the LAN led to blink 5 times
3. Release reset and power buttons
4. The rescue page is accessible via http://192.168.1.1
5. Select the OpenWrt factory image and start upgrade
6. Wait for the router to flash new firmware and reboot

Revert to stock firmware:

 i. Download the stock firmware from GL.Inet website
 ii. Use the same method explained above to flash the stock firmware

Signed-off-by: Victorien Molle <victorien.molle@wifirst.fr>
[update commit message]
Signed-off-by: David Bauer <mail@david-bauer.net>

target/linux/ath79/dts/qca9531_glinet_gl-xe300.dts

@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "qca953x.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	compatible = "glinet,gl-xe300", "qca,qca9531";
+	model = "GL.iNet GL-XE300";
+
+	gpio-export {
+		compatible = "gpio-export";
+
+		gpio_lte_power {
+			gpios = <&gpio 0 GPIO_ACTIVE_HIGH>;
+			gpio-export,name = "lte_power";
+			gpio-export,output = <1>;
+		};
+
+		gpio_sd_detect {
+			gpios = <&gpio 17 GPIO_ACTIVE_LOW>;
+			gpio-export,name = "sd_detect";
+			gpio-export,output = <0>;
+		};
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&jtag_disable_pins>;
+
+		reset {
+			label = "reset";
+			linux,code = <KEY_RESTART>;
+			gpios = <&gpio 3 GPIO_ACTIVE_LOW>;
+		};
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		lan {
+			gpios = <&gpio 10 GPIO_ACTIVE_LOW>;
+			label = "green:lan";
+		};
+
+		wan {
+			gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
+			label = "green:wan";
+		};
+
+		wlan {
+			gpios = <&gpio 12 GPIO_ACTIVE_LOW>;
+			label = "green:wlan";
+			linux,default-trigger = "phy0tpt";
+		};
+
+		lte {
+			gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
+			label = "green:lte";
+		};
+	};
+};
+
+&pcie0 {
+	status = "okay";
+};
+
+&usb0 {
+	status = "okay";
+};
+
+&usb_phy {
+	status = "okay";
+};
+
+&spi {
+	status = "okay";
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <25000000>;
+
+		partitions {
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "u-boot";
+				reg = <0x0 0x40000>;
+				read-only;
+			};
+
+			partition@40000 {
+				label = "u-boot-env";
+				reg = <0x40000 0x10000>;
+			};
+
+			art: partition@50000 {
+				label = "art";
+				reg = <0x50000 0x10000>;
+				read-only;
+			};
+
+			partition@60000 {
+				label = "kernel";
+				reg = <0x60000 0x400000>;
+			};
+
+			partition@460000 {
+				label = "nor_reserved";
+				reg = <0x460000 0xba0000>;
+			};
+		};
+	};
+
+	flash@1 {
+		compatible = "spi-nand";
+		reg = <1>;
+		spi-max-frequency = <25000000>;
+
+		partitions {
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "ubi";
+				reg = <0x0 0x8000000>;
+			};
+		};
+	};
+};
+
+&eth0 {
+	status = "okay";
+
+	phy-handle = <&swphy4>;
+
+	nvmem-cells = <&macaddr_art_0>;
+	nvmem-cell-names = "mac-address";
+	mtd-mac-address-increment = <1>;
+};
+
+&eth1 {
+	nvmem-cells = <&macaddr_art_0>;
+	nvmem-cell-names = "mac-address";
+};
+
+&wmac {
+	status = "okay";
+
+	mtd-cal-data = <&art 0x1000>;
+};
+
+&art {
+	compatible = "nvmem-cells";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	macaddr_art_0: macaddr@0 {
+		reg = <0x0 0x6>;
+	};
+};

target/linux/ath79/image/nand.mk

@@ -195,6 +195,22 @@ define Device/glinet_gl-e750
 endef
 TARGET_DEVICES += glinet_gl-e750
 
+define Device/glinet_gl-xe300
+  SOC := qca9531
+  DEVICE_VENDOR := GL.iNet
+  DEVICE_MODEL := GL-XE300
+  DEVICE_PACKAGES := kmod-usb2 block-mount kmod-usb-serial-ch341
+  KERNEL_SIZE := 4096k
+  IMAGE_SIZE := 131072k
+  PAGESIZE := 2048
+  VID_HDR_OFFSET := 2048
+  BLOCKSIZE := 128k
+  IMAGES += factory.img
+  IMAGE/factory.img := append-kernel | pad-to $$$$(KERNEL_SIZE) | append-ubi
+  IMAGE/sysupgrade.bin := sysupgrade-tar | append-metadata
+endef
+TARGET_DEVICES += glinet_gl-xe300
+
 # fake rootfs is mandatory, pad-offset 129 equals (2 * uimage_header + 0xff)
 define Device/netgear_ath79_nand
   DEVICE_VENDOR := NETGEAR