qualcommax: ipq50xx: Add support for Yuncore AX830

qualcommax: ipq50xx: Add support for Yuncore AX830

Specifications:
SOC: Qualcomm IPQ5018 (64-bit dual-core ARM Cortex-A53 @ 1.0Ghz)
Memory: 512MB DDR3L
Standard: 802.11ax/ac/b/g/n
Flash: SPI NOR 8MB (Winbond W25Q64DW) + NAND 128MB (Winbond W25N01GWZEIG)
2.4G Frequency: 2.4GHz - 2.484GHz
2.4G Wi-Fi standard: 802.11b/g/n/ax
5.8G Frequency: 4.9~5.9G
5.8G Wi-Fi Standard: 802.11 a/n/ac/ax
Interface:
  Optional 1(Without 8081):
    1 * 10/100 /1000Mbps RJ45 WAN Port and PoE port;
    1* Gigabit Console port;
  Optional 2(With 8081):
    1 * 10/100/1000/2500Mbps RJ45 WAN port and PoE port,
    1*10/100/1000Mbps LAN port
Buttons: 1 * Reset button, press 10 seconds to revert to default setting
Antenna: Build in 4*4dBi dual band MIMO Antenna
Data Rate: 3000Mbps （2.4G 600Mbps, 5.8G 2400Mbps）
End Users: 128+
2.4G RF Power: ≤ 23dBm
5.8G RF Power: ≤ 23dBm
DC: 12V----2A
PoE: 48V (IEEE 802.3at)
LED Light: Sys, WAN, LAN
Power Consumption: ≤ 20W

BACKUP YOUR STOCK FIRMWARE:
- Put openwrt-*-initramfs-uImage.itb to your
  TFTP server and rename it to initramfs.bin
- Enable serial console and enter to u-boot cli
  and exec these commands:
    ```
    tftpboot <your_tftp_server_ip>:initramfs.bin
    bootm
    ```
- Once boot completed and you get the openwrt shell
  execute below commands:
    ```
    device=ax830
    mkdir -p /tmp/fw_backup; cd /tmp/fw_backup
    rootfs=$(cat /proc/mtd | grep \"rootfs\" | cut -d: -f1)
    rootfs_1=$(cat /proc/mtd | grep \"rootfs_1\" | cut -d: -f1)
    dd if=/dev/${rootfs} of=rootfs_${rootfs} bs=1M
    dd if=/dev/${rootfs_1} of=rootfs_1_${rootfs_1} bs=1M
    cp /sys/firmware/fdt fdt.dtb
    md5sum * > md5sum
    tar -cvzf /tmp/${device}.tar.gz .
    sum=$(md5sum /tmp/${device}.tar.gz | cut -d' ' -f1)
    mv /tmp/${device}.tar.gz /tmp/${device}_${sum}.tar.gz
    echo "stock fw backup saved to: /tmp/${device}_${sum}.tar.gz"
    ```
- Upload/save your backup to a safe place.

STOCK FIRMWARE RECOVERY:
- Boot initramfs image
- Upload your backed-up stock fw tarball to the device
  using scp or download it from the device using wget.
- Enter device ssh cli or tty and exec:
    ```
    cd /tmp && wget <your_web_server_ip>/${stock_fw_backup}.tar.gz`
    tar -xpzf ${stock_fw_backup}.tar.gz
    rootfs=$(cat /proc/mtd | grep \"rootfs\" | cut -d: -f1)
    rootfs_1=$(cat /proc/mtd | grep \"rootfs_1\" | cut -d: -f1)
    ubiformat /dev/${rootfs} -y -f /tmp/rootfs_${rootfs}
    ubiformat /dev/${rootfs_1} -y -f /tmp/rootfs_1_${rootfs_1}
    reboot
    ```

INSTALLATION:
1. initramfs method
- Put openwrt-*-initramfs-uImage.itb to your
  TFTP server and rename it to initramfs.bin
- Enable serial console and enter to u-boot cli
  and exec these commands:
    ```
    tftpboot <your_tftp_server_ip>:initramfs.bin
    bootm
    ```
- Once boot completed and you get the openwrt shell
  execute below commands:
    ```
    cd /tmp && wget <your_web_server_ip>/factory.ubi`
    export rootfs=$(cat /proc/mtd | grep rootfs | cut -d: -f1)
    export rootfs_1=$(cat /proc/mtd | grep rootfs_1 | cut -d: -f1)
    ubiformat /dev/${rootfs} -y -f factory.ubi
    ubiformat /dev/${rootfs_1} -y -f factory.ubi
    reboot
    ```

2. u-boot factory.ubi image method
- Put factory.ubi to your TFTP server and
  enter u-boot cli and exec these commands:
    ```
    tftpboot <your_tftp_server_ip>:factory.ubi
    #After downloading is finished:
    flash rootfs
    flash rootfs_1
    reset
    ```

Signed-off-by: Shubham Vishwakarma <shubhamvis98@fossfrog.in>
Link: https://github.com/openwrt/openwrt/pull/18968
Signed-off-by: Robert Marko <robimarko@gmail.com>