i tried to install unofficial twrp for redmi note 9. But ended up bricking my phone. -The pc can recognise phone(there is windows sound, every 10 seconds) -Phone is not showing anything -MiFlashTool v1/v2 cannot see my phone, i used v2 to turn into fastboot but later couldnt reinstall global rom. I just need to get into fastboot so I will install official rom, but I need to turn fastboot from computer
Furthermore it is necessary to disable AVB before doing any modifications. The flashing instructions are incomplete. Before flashing
twrp.img make sure to flash "empty" vbmeta images
fastboot flash --disable-verity --disable-verification vbmeta vbmeta.img fastboot flash --disable-verity --disable-verification vbmeta_system vbmeta_system.img fastboot flash --disable-verity --disable-verification vbmeta_vendor vbmeta_vendor.img
fastboot is relatively safe for flashing, however unlocked bootloader is required. therefore when flashing in fastboot mode do not flash with flash_all_lock.bat, do not try to re-lock bootloader.
when flashing in SP Flash tool observe the golden rules:
never use any scatter file that does not match your current partition layout/device/ROM
the file name MT6769_Android_scatter.txt is no guarantee. even the Redmi Note 9 MT6769V/CZ comes in two different versions 128/64GB.
fastboot getvar allmay give some partition related information.
WwR MTK v2.51 is the safest way to create own scatter file
always un-tick preloader checkbox
we do not want to flash preloader as this is the most imporant area in EMMC_BOOT responsible for receiving flashing instructions. if the preloader is broken, the only way to recover dead phone is from Engineering mode via KCOLO test point
flash in "Download only" mode only
other modes will erase your emmc which destroys secure boot