qualcommax: ipq60xx: add Linksys MR7500 support

qualcommax: ipq60xx: add Linksys MR7500 support

Codename: Divo

Hardware specification:
========
SoC: Qualcomm IPQ6018
RAM: 512MB (2x ESMT 256MB DDR3L M15T2G16128A–DEBG2R)
NAND Flash: 512MB (Macronix MX30UF4G18AC or SK Hynix H27S4G8F2EDA-BC)
Ethernet: 1x 10/100/1000/2500/5000Mbps (Marvell AQR114C-B0)
Ethernet: 4x 10/100/1000Mbps (Qualcomm QCA8075)
WiFi1: 6GHz ax 4x4@20/40/160 MHz (Qualcomm QCN9024 + Skyworks SKY85784-11) - channels 33-229
WiFi2: 5GHz ax 2x2@20/40/80 MHz (Qualcomm QCN5052 + Skyworks SKY85755-11) - channels 36-177
WiFi3: 2.4GHz ax 2x2@20/40 MHz (Qualcomm QCN5022 + Skyworks SKY8340-11)
IoT: Bluetooth 5 (CSR8811) - not implemented
LED: 1x RGB status + USB Blue (PWM)
USB: 1x USB 3.0
Button: WPS, Reset

Flash instructions (Without Serial):
========
Open Linksys Web UI - http://192.168.1.1/ca or http://linksysxxxxx.lan/ca depending on your setup.
  xxxxx is the last 5 digits from the SN found on a sticker under the device.
Click on the Linksys Logo to by-pass smart app registration.
Login with your admin password. The default password can be found on the same sticker.
To enter into the support mode, click on the “CA” link and the bottom of the page.
Open the “Connectivity” menu and upload the squash-factory image with the “Choose file” button.
Click start. Ignore all the prompts and warnings by click “yes” in all the popups.

Flash instructions (With Serial):
========
1. Installation using serial connection from OEM firmware (default login: root, password: admin):
- fw_printenv -n boot_part
In case of 2:
- flash_erase /dev/mtd13 0 0
- nandwrite -p /dev/mtd13 openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin
or in case of 1:
- flash_erase /dev/mtd15 0 0
- nandwrite -p /dev/mtd15 openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin
After first boot install firmware on second partition:
- mtd -r -e kernel -n write openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin kernel
or:
- mtd -r -e alt_kernel -n write openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin alt_kernel

2. Installation from initramfs image using USB drive:
Put the initramfs image on the USB drive:
- dd bs=1M if=openwrt-qualcommax-ipq60xx-linksys_mr7500-initramfs-uImage.itb of=/dev/sda
Stop u-boot and run:
- usb start && usbboot $loadaddr 0 && bootm $loadaddr
Write firmware to the flash from initramfs:
- mtd -e kernel -n write openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin kernel
and:
- mtd -r -e alt_kernel -n write openwrt-qualcommax-ipq60xx-linksys_mr7500-squashfs-factory.bin alt_kernel

3. Back to the OEM firmware:
- mtd -e kernel -n write FW_MR7500_1.1.12.211919_prod.img kernel
and:
- mtd -r -e alt_kernel -n write FW_MR7500_1.1.12.211919_prod.img alt_kernel

4. USB recovery:
Put the initramfs image on the USB:
- dd bs=1M if=openwrt-qualcommax-ipq60xx-linksys_mr7500-initramfs-uImage.itb of=/dev/sda
Set u-boot env:
- fw_setenv bootusb 'usb start && usbboot $loadaddr 0 && bootm $loadaddr'
- fw_setenv bootcmd 'run bootusb; if test $auto_recovery = no; then bootipq; elif test $boot_part = 1; then run bootpart1; else run bootpart2; fi'

AQR firmware:
========
0. Firmware extracting:
To extract the firmware, use unblob (unblob.org)
1. Firmware loading:
To properly load the firmware and initialize AQR PHY, we must use the u-boot aq_load_fw function.
To do this, you need to modify u-boot env:
With USB recovery:
- fw_setenv bootcmd 'aq_load_fw; run bootusb; if test $auto_recovery = no; then bootipq; elif test $boot_part = 1; then run bootpart1; else run bootpart2; fi'
and without:
- fw_setenv bootcmd 'aq_load_fw; if test $auto_recovery = no; then bootipq; elif test $boot_part = 1; then run bootpart1; else run bootpart2; fi'
2. Firmware updating:
Newer firmware (AQR114C.cld) is available in the latest OEM firmware (https://downloads.linksys.com/support/assets/firmware/FW_MR7500_1.1.12.211919_prod.img).
Copy AQR114C.cld to /lib/firmware/marvell

Link: openwrt#17428

Signed-off-by: Weikai Kong <priv@pppig236.com>
Link: https://github.com/openwrt/openwrt/pull/18185
Signed-off-by: Robert Marko <robimarko@gmail.com>