ramips: add support for Belkin RT1800

Belkin RT1800 is an 802.11ax (Wi-Fi 6) router, based on MediaTek
MT7621A.

Specifications:
- SoC: MT7621 (880MHz, 2 Cores)
- RAM: 256 MB
- Flash: 128 MB NAND
- Wi-Fi:
  - MT7915D: 2.4/5 GHz (DBDC)
- Ethernet: 5x 1GiE MT7530
- USB: 1x USB 3.0
- UART: J4 (57600 baud)
  - Pinout: [3V3] (TXD) (RXD) (blank) (GND)

Notes:
* This device has a dual-boot partition scheme, but this firmware works
  only on boot partition 1.

Installation:

Upload the generated factory.bin image via the stock web firmware
updater.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

package/boot/uboot-envtools/files/ramips

@@ -47,6 +47,7 @@ zbtlink,zbt-wg2626|\
 zte,mf283plus)
 	ubootenv_add_uci_config "/dev/mtd1" "0x0" "0x1000" "0x10000"
 	;;
+belkin,rt1800|\
 h3c,tx1800-plus|\
 h3c,tx1801-plus|\
 h3c,tx1806|\

target/linux/ramips/dts/mt7621_belkin_rt1800.dts

@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "mt7621.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+#include <dt-bindings/leds/common.h>
+
+/ {
+	compatible = "belkin,rt1800", "mediatek,mt7621-soc";
+	model = "Belkin RT1800";
+
+	aliases {
+		led-boot = &led_power;
+		led-failsafe = &led_power;
+		led-running = &led_power;
+		led-upgrade = &led_power;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,115200";
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		reset {
+			label = "reset";
+			gpios = <&gpio 6 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RESTART>;
+		};
+
+		wps {
+			label = "wps";
+			gpios = <&gpio 18 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_WPS_BUTTON>;
+		};
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led_power: led-power {
+			label = "white:power";
+			gpios = <&gpio 14 GPIO_ACTIVE_LOW>;
+			default-state = "on";
+		};
+
+		led-wan {
+			color = <LED_COLOR_ID_WHITE>;
+			function = LED_FUNCTION_WAN;
+			gpios = <&switch0 0 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&nand {
+	status = "okay";
+
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		partition@0 {
+			label = "Boot";
+			reg = <0x0 0x80000>;
+			read-only;
+		};
+
+		partition@80000 {
+			label = "Config";
+			reg = <0x80000 0x80000>;
+		};
+
+		factory: partition@100000 {
+			label = "Factory";
+			reg = <0x100000 0x80000>;
+			read-only;
+		};
+
+		partition@180000 {
+			label = "firmware";
+			reg = <0x180000 0x3000000>;
+
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "kernel";
+				reg = <0x0 0x400000>;
+			};
+
+			partition@400000 {
+				label = "ubi";
+				reg = <0x400000 0x2c00000>;
+			};
+		};
+
+		partition@3180000 {
+			label = "alt_firmware";
+			reg = <0x3180000 0x3000000>;
+			read-only;
+		};
+
+		partition@6180000 {
+			label = "cbtinfo";
+			reg = <0x6180000 0x80000>;
+			read-only;
+		};
+		/* seems to be the end here. Can't read past 0x6200000 */
+	};
+};
+
+&pcie {
+	status = "okay";
+};
+
+&pcie1 {
+	wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x0000>;
+	};
+};
+
+&gmac1 {
+	status = "okay";
+	label = "wan";
+	phy-handle = <&ethphy0>;
+};
+
+&mdio {
+	ethphy0: ethernet-phy@0 {
+		reg = <0>;
+	};
+};
+
+&switch0 {
+	gpio-controller;
+	#gpio-cells = <2>;
+
+	ports {
+		port@1 {
+			status = "okay";
+			label = "lan4";
+		};
+
+		port@2 {
+			status = "okay";
+			label = "lan3";
+		};
+
+		port@3 {
+			status = "okay";
+			label = "lan2";
+		};
+
+		port@4 {
+			status = "okay";
+			label = "lan1";
+		};
+	};
+};

target/linux/ramips/image/mt7621.mk

@@ -70,6 +70,30 @@ define Build/iodata-mstc-header
 	)
 endef
 
+define Build/belkin-header
+	$(eval magic=$(word 1,$(1)))
+	$(eval hw_ver=$(word 2,$(1)))
+	$(eval fw_ver=$(word 3,$(1)))
+
+	( \
+		type_fw_date=$$(printf "01%02x%02x%02x" \
+			$$(date -d "@$(SOURCE_DATE_EPOCH)" "+%y %m %d")); \
+		hw_fw_ver=$$(printf "%02x%02x%02x%02x" \
+			$(hw_ver) $$(echo $(fw_ver) | cut -d. -f-3 | tr . ' ')); \
+		fw_len_crc=$$(gzip -c $@ | tail -c 8 | od -An -tx8 | tr -d ' \n'); \
+		fw_crc_len="$${fw_len_crc:8:8}$${fw_len_crc:0:8}"; \
+		\
+		printf "$(magic)" | dd bs=4 count=1 conv=sync 2>/dev/null; \
+		printf "$$(echo $${type_fw_date}$${hw_fw_ver} | \
+			sed 's/../\\x&/g')"; \
+		printf "$$(echo $${fw_crc_len}$${fw_crc_len} | \
+			sed 's/../\\x&/g')"; \
+		printf "\x5c\x78\x00\x00"; \
+		cat $@; \
+	) > $@.new
+	mv $@.new $@
+endef
+
 define Build/ubnt-erx-factory-image
 	if [ -e $(KDIR)/tmp/$(KERNEL_INITRAMFS_IMAGE) -a "$$(stat -c%s $@)" -lt "$(KERNEL_SIZE)" ]; then \
 		echo '21001:7' > $(1).compat; \
@@ -341,6 +365,27 @@ define Device/beeline_smartbox-turbo
 endef
 TARGET_DEVICES += beeline_smartbox-turbo
 
+define Device/belkin_rt1800
+  $(Device/dsa-migration)
+  BLOCKSIZE := 128k
+  PAGESIZE := 2048
+  KERNEL_SIZE := 4096k
+  IMAGE_SIZE := 49152k
+  DEVICE_VENDOR := Belkin
+  DEVICE_MODEL := RT1800
+  DEVICE_PACKAGES := kmod-mt7915e kmod-usb3 uboot-envtools
+  UBINIZE_OPTS := -E 5
+  KERNEL_LOADADDR := 0x82000000
+  KERNEL := kernel-bin | relocate-kernel 0x80001000 | lzma | \
+	fit lzma $$(KDIR)/image-$$(firstword $$(DEVICE_DTS)).dtb | \
+	append-squashfs4-fakeroot
+  IMAGES += factory.bin
+  IMAGE/sysupgrade.bin := sysupgrade-tar | append-metadata
+  IMAGE/factory.bin := append-kernel | pad-to $$$$(KERNEL_SIZE) | \
+	append-ubi | check-size | belkin-header RT18 1 9.9.9
+endef
+TARGET_DEVICES += belkin_rt1800
+
 define Device/buffalo_wsr-1166dhp
   $(Device/dsa-migration)
   $(Device/uimage-lzma-loader)

target/linux/ramips/mt7621/base-files/etc/board.d/01_leds

@@ -28,6 +28,9 @@ beeline,smartbox-giga|\
 beeline,smartbox-turbo)
 	ucidef_set_led_netdev "wan" "wan" "blue:wan" "wan"
 	;;
+belkin,rt1800)
+	ucidef_set_led_netdev "wan" "wan" "white:wan" "wan"
+	;;
 cudy,wr2100)
 	ucidef_set_led_netdev "lan1" "lan1" "green:lan1" "lan1"
 	ucidef_set_led_netdev "lan2" "lan2" "green:lan2" "lan2"

target/linux/ramips/mt7621/base-files/etc/board.d/02_network

@@ -205,6 +205,11 @@ ramips_setup_macs()
 		wan_mac=$lan_mac
 		label_mac=$lan_mac
 		;;
+	belkin,rt1800)
+		lan_mac=$(mtd_get_mac_ascii Config lan_hwaddr)
+		wan_mac=$(mtd_get_mac_ascii Config wan_hwaddr)
+		label_mac=$lan_mac
+		;;
 	mikrotik,routerboard-750gr3|\
 	mikrotik,routerboard-760igs|\
 	mikrotik,routerboard-m11g|\

target/linux/ramips/mt7621/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac

@@ -84,6 +84,11 @@ case "$board" in
 		[ "$PHYNBR" = "0" ] && macaddr_add $hw_mac_addr 1 > /sys${DEVPATH}/macaddress
 		[ "$PHYNBR" = "1" ] && macaddr_add $hw_mac_addr 2 > /sys${DEVPATH}/macaddress
 		;;
+	belkin,rt1800)
+		hw_mac_addr=$(mtd_get_mac_ascii Config wan_hwaddr)
+		[ "$PHYNBR" = "0" ] && macaddr_add $hw_mac_addr 1 > /sys${DEVPATH}/macaddress
+		[ "$PHYNBR" = "1" ] && macaddr_add $hw_mac_addr 2 > /sys${DEVPATH}/macaddress
+		;;
 	netgear,wax202)
 		hw_mac_addr=$(mtd_get_mac_ascii Config mac)
 		[ "$PHYNBR" = "0" ] && macaddr_add $hw_mac_addr 2 > /sys${DEVPATH}/macaddress

target/linux/ramips/mt7621/base-files/etc/init.d/bootcount

@@ -22,6 +22,7 @@ boot() {
 	linksys,ea8100-v2)
 		mtd resetbc s_env || true
 		;;
+	belkin,rt1800|\
 	samknows,whitebox-v8)
 		fw_setenv bootcount 0
 		;;

target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh

@@ -57,6 +57,7 @@ platform_do_upgrade() {
 	beeline,smartbox-flash|\
 	beeline,smartbox-giga|\
 	beeline,smartbox-turbo|\
+	belkin,rt1800|\
 	dlink,dir-1960-a1|\
 	dlink,dir-2640-a1|\
 	dlink,dir-2660-a1|\