I powered up my old intel headunit since the new UIS7682 is now installed and decided to see if I could root it. It took a couple of attempts but what finally worked was:
- creating an android virtual device on an intel machine using the x86_64 android image on API 27 (android 8.1)
- installing the latest magisk on that AVD and use it to patch the boot.img (from the 2020.4.7firmware)
- stuff the patched boot.img into the 6521_1.zip and then run the signing proess/tool on it
- take the new 6521_1.zip and put it and the other firmware update files on a usb stick and flash
I have root. Tho magisk is complaining about signature verification. Might have to install mods manually. No biggy.
Unit Specifics :
Joying 10.1'' 2006 - 2012 Toyota RAV4 Android 8.1.0 Plug and Play Car Auto Radio with DSP
SKU: JY-TO151N3-JY-TO151N4GS
Firmware: 9853i OS 1024X600 800X480 1280X720 2020.4.7 (8.1.0)