This post is coming from my unpublished archive. It's quite an old one, but I think it would be interesting to share it. This is a summary of the different steps used to flash a Xiaomi Mi A3 phone and install another Android version (e.g. Lineage OS, Kali, /e/...). A part of the links are gone unfortunately, but I think the most important ones are still available. Have fun!
Bootstrapping
This installation was done on Ubuntu 21.04 due to compatibility with other system.
install latest android sdk from official website from https://developer.android.com/studio/#downloads
Download all required assets to flash your phone
Procedure
This image is open-source but was built by Harukey. This is a good method to root your android phone though.
Ensure ADB is correctly installed on your PC
Ensure Fastboot is correctly installed on your PC
Enable developer mode
Enable debugging throught USB
Connect your USB cable to your phone
Reboot your phone and press volume down
When fastboot prompt appears you can flash your phone with the recovery image
wget https://downloads.sourceforge.net/project/harukeys-roms/laurel/LineageOS18/LinageOSRecovery20210917.img
fastboot flash boot LinageOSRecovery20210917.img
- Reboot into normal mode and check if everything was correctly set and configured. You should have your old Android version. (unplug your phone).
fastboot reboot
- Reboot in recovery mode
adb reboot recovery
- In recovery mode apply the latest partitions an update with ADB
adb sideload copy-partitions-20200903_1329.zip
Do a factory reset (present at the first menu page)
Apply another update, this time, with the lineageOS rom
wget https://downloads.sourceforge.net/project/harukeys-roms/laurel/LineageOS18/lineage-18.1-20211128-UNOFFICIAL-laurel_sprout.zip
adb sideload lineage-18.1-20211128-UNOFFICIAL-laurel_sprout.zip
Reboot in normal mode
Reboot in recovery mode
adb reboot recovery
- Download and install Magisk
wget https://github.com/topjohnwu/Magisk/releases/download/v24.3/Magisk-v24.3.apk
cp Magisk-v24.3.apk Magisk-v24.3.zip
adb sideload Magisk-v24.3.zip
Reboot in normal mode and check if you can have access to LineageOS and Magisk.
Configure your system as desired (set developer mode and USB debugging).
Reboot in recovery mode
Download and install nethunter
adb sideload nethunter-2022.1-laurel_sprout-eleven-kalifs-full.zip
- reboot your system and configure nethunter.
The procedure to install this image is available on xda-developer forum: https://forum.xda-developers.com/t/rom-11-unofficial-laurel_sprout-oss-lineageos-18-1.4240953/
Unbrick Xiaomi Mi A3
Shit happens sometime. Xiaomi Mi A3 can be bricked if you do a wrong configuration or don't follow the good process when trying to install LineageOS or any kind of alternative to android. Fortunately, this phone can easily be unbricked by using few tools. Here the requirement:
windows 10 (at this time, it's a requirement unfortunately)
qpsttool (version I used was 2.7.480 but the latest was 2.7.496)
service rom by @nullby
Other steps are explained in depth in Mi A3 unbrick guide by @nullby. It takes around 30/45 minutes to unbrick your phone, and start with a fresh version of android one installed.
Fixing a bootloop
You can use TWPRP image, in my case twrp-3.3.1-17-laurel_sprout-Q-mauronofrio.img worked. Go into advanced settings and "fix bootloop".
References and Resources
https://www.getdroidtips.com/how-to-unlock-bootloader-of-xiaomi-mi-a3/
https://forum.xda-developers.com/t/mi-a3-bricked-blackscreen-not-turning-on.4214225/
https://forum.xda-developers.com/t/rom-official-fastboot-xiaomi-mi-a3-laurel_sprout.3962489/
https://forum.xda-developers.com/t/rom-stable-lineageos-18-0-mi-a3-laurel_sprout.4174895/
https://germowp.blogspot.com/2021/01/mi-m1803e6g-test-point-7reboot-device.html
https://github.com/pixelExperience-Devices/kernel_xiaomi_laurel_sprout
https://www.mobilerdx.com/2019/07/xiaomi-mi-a3-edl-mode-pinout-mi-a3-test-point.html
https://xiaomitools.com/how-to-use-qualcomm-flash-image-loader-tool-qfil/