ramips: add support for SIM SIMAX1800U

SIM SIMAX1800U has the similar hardware design as the SIMAX1800T. The
only difference is the Ethernet portmap.

Specification
-------------
- SoC       : Mediatek MT7621
- RAM       : 256 MiB DDR3
- Flash     : 128 MiB NAND Flash
- WLAN      : Mediatek MT7905 DBDC
  - 2.4 GHz : 2x2 MIMO WiFi6
  - 5 GHz   : 2x2 MIMO WiFi6
- Ethernet  : MT7621 built-in 10/100/1000 Mbps 1x WAN; 3x LAN
- UART      : 3.3V, 115200n8
- Buttons   : 1x RESET; 1x WPS/MESH
- LEDs      : 1x Multi-Color(Blue;Green;Red)
- Power     : DC 12V1A
- CMIIT ID  : 2022AP7163
- TFTP IP   :
  - server  : 192.168.1.254
  - router  : 192.168.1.28

TFTP Installation(recommend)
------------
1. Set local tftp server IP "192.168.1.254" and NetMask "255.255.255.0".
2. Rename initramfs-kernel.bin to "factory.bin" and put it in the root
   directory of the tftp server. tftpd64 is a good choice for Windows.
3. Remove all Ethernet cables and WiFi connections from the PC, except
   for the one connected to the SIMAX1800U. Start the TFTP server, plug
   in the power adapter and wait for the OpenWrt system to boot.
4. Backup "firmware" partition and rename it to "firmware.bin". We need
   it to back to the stock firmware.
5. Use "fw_printenv" command to list envs. If "firmware_select=2" is
   observed then set u-boot env variable via command:
   `fw_setenv firmware_select 1`
6. Apply sysupgrade.bin in OpenWrt LuCI.

Web UI Installation
------------
1. Apply update by uploading initramfs-factory.bin to the web UI.
2. Use "fw_printenv" command to list envs. If "firmware_select=2" is
   observed then set u-boot env variable via command:
   `fw_setenv firmware_select 1`
3. Apply squashfs-sysupgrade.bin in OpenWrt LuCI.

Return to Stock Firmware
----------------------------
  Restore the backup firmware partition in the installation step 4.

MAC addresses
-------------
+---------+-------------------+
|         | MAC example       |
+---------+-------------------+
| LABEL   | 98:xx:xx:xx:xx:b2 |
| LAN     | 98:xx:xx:xx:xx:b5 |
| WAN     | 98:xx:xx:xx:xx:b2 |
| WLAN2G  | 98:xx:xx:xx:xx:b4 |
| WLAN5G  | 9a:xx:xx:xx:xx:b4 |
+---------+-------------------+

Tips:
-----------
  User can use `TFTP Installation` method to recover a brick device.

Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Link: https://github.com/openwrt/openwrt/pull/19455
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

8 files changed, 79 insertions, 9 deletions

diff --git a/target/linux/ramips/dts/mt7621_haier-sim_wr1800k.dtsi b/target/linux/ramips/dts/mt7621_haier-sim_wr1800k.dtsi
index dd7b72707e..8bd63967c0 100644
--- a/target/linux/ramips/dts/mt7621_haier-sim_wr1800k.dtsi
+++ b/target/linux/ramips/dts/mt7621_haier-sim_wr1800k.dtsi
@@ -67,16 +67,10 @@
 &gmac1 {
 	status = "okay";
 	label = "wan";
-	phy-handle = <&ethphy4>;
-
 	nvmem-cells = <&macaddr_factory_8004 (-3)>;
 	nvmem-cell-names = "mac-address";
 };
 
-&ethphy4 {
-	/delete-property/ interrupts;
-};
-
 &nand {
 	status = "okay";
 
@@ -166,7 +160,6 @@
 	ports {
 		port@1 {
 			status = "okay";
-			label = "lan3";
 		};
 
 		port@2 {
@@ -176,7 +169,6 @@
 
 		port@3 {
 			status = "okay";
-			label = "lan1";
 		};
 	};
 };
diff --git a/target/linux/ramips/dts/mt7621_haier_har-20s2u1.dts b/target/linux/ramips/dts/mt7621_haier_har-20s2u1.dts
index dede7dbb20..8c1b23f8eb 100644
--- a/target/linux/ramips/dts/mt7621_haier_har-20s2u1.dts
+++ b/target/linux/ramips/dts/mt7621_haier_har-20s2u1.dts
@@ -6,3 +6,23 @@
 	compatible = "haier,har-20s2u1", "mediatek,mt7621-soc";
 	model = "Haier HAR-20S2U1";
 };
+
+&ethphy4 {
+	/delete-property/ interrupts;
+};
+
+&gmac1 {
+	phy-handle = <&ethphy4>;
+};
+
+&switch0 {
+	ports {
+		port@1 {
+			label = "lan3";
+		};
+
+		port@3 {
+			label = "lan1";
+		};
+	};
+};
diff --git a/target/linux/ramips/dts/mt7621_sim_simax1800t.dts b/target/linux/ramips/dts/mt7621_sim_simax1800t.dts
index 3c5c9179d2..b75af605bb 100644
--- a/target/linux/ramips/dts/mt7621_sim_simax1800t.dts
+++ b/target/linux/ramips/dts/mt7621_sim_simax1800t.dts
@@ -6,3 +6,23 @@
 	compatible = "sim,simax1800t", "mediatek,mt7621-soc";
 	model = "SIM SIMAX1800T";
 };
+
+&ethphy4 {
+	/delete-property/ interrupts;
+};
+
+&gmac1 {
+	phy-handle = <&ethphy4>;
+};
+
+&switch0 {
+	ports {
+		port@1 {
+			label = "lan3";
+		};
+
+		port@3 {
+			label = "lan1";
+		};
+	};
+};
diff --git a/target/linux/ramips/dts/mt7621_sim_simax1800u.dts b/target/linux/ramips/dts/mt7621_sim_simax1800u.dts
new file mode 100644
index 0000000000..70fff673f5
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_sim_simax1800u.dts
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "mt7621_haier-sim_wr1800k.dtsi"
+
+/ {
+	compatible = "sim,simax1800u", "mediatek,mt7621-soc";
+	model = "SIM SIMAX1800U";
+};
+
+&ethphy0 {
+	/delete-property/ interrupts;
+};
+
+&gmac1 {
+	phy-handle = <&ethphy0>;
+};
+
+&switch0 {
+	ports {
+		port@1 {
+			label = "lan1";
+		};
+
+		port@3 {
+			label = "lan3";
+		};
+	};
+};
diff --git a/target/linux/ramips/image/mt7621.mk b/target/linux/ramips/image/mt7621.mk
index 2549f353e9..578c293224 100644
--- a/target/linux/ramips/image/mt7621.mk
+++ b/target/linux/ramips/image/mt7621.mk
@@ -2615,6 +2615,13 @@ define Device/sim_simax1800t
 endef
 TARGET_DEVICES += sim_simax1800t
 
+define Device/sim_simax1800u
+  $(Device/haier-sim_wr1800k)
+  DEVICE_VENDOR := SIM
+  DEVICE_MODEL := SIMAX1800U
+endef
+TARGET_DEVICES += sim_simax1800u
+
 define Device/snr_snr-cpe-me1
   $(Device/dsa-migration)
   $(Device/uimage-lzma-loader)
diff --git a/target/linux/ramips/mt7621/base-files/etc/board.d/02_network b/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
index 1e194fef5f..c12c46dc10 100644
--- a/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
+++ b/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
@@ -22,6 +22,7 @@ ramips_setup_interfaces()
 	mercusys,mr70x-v1|\
 	netgear,wax202|\
 	sim,simax1800t|\
+	sim,simax1800u|\
 	tplink,mr600-v2-eu|\
 	xiaomi,mi-router-3-pro|\
 	xiaomi,mi-router-ac2100|\
diff --git a/target/linux/ramips/mt7621/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac b/target/linux/ramips/mt7621/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac
index 0c9c98399a..21ab3f16ea 100644
--- a/target/linux/ramips/mt7621/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac
+++ b/target/linux/ramips/mt7621/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac
@@ -105,7 +105,8 @@ case "$board" in
 		;;
 	haier,har-20s2u1|\
 	jcg,y2|\
-	sim,simax1800t)
+	sim,simax1800t|\
+	sim,simax1800u)
 		[ "$PHYNBR" = "1" ] && \
 			macaddr_setbit_la "$(mtd_get_mac_binary factory 0x4)" > /sys${DEVPATH}/macaddress
 		;;
diff --git a/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh b/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
index 9180118f3d..a1f14f9d78 100755
--- a/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
+++ b/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
@@ -138,6 +138,7 @@ platform_do_upgrade() {
 	sercomm,na502|\
 	sercomm,na502s|\
 	sim,simax1800t|\
+	sim,simax1800u|\
 	tplink,ec330-g5u-v1|\
 	wifire,s1500-nbn|\
 	xiaomi,mi-router-3g|\