Author Topic: Upgrading to 8.1 while preserving data+root, TWRP broken  (Read 1882 times)

amsomniac

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Upgrading to 8.1 while preserving data+root, TWRP broken
« on: May 16, 2019, 10:46:11 am »
Hey all! I've only recently joined this forum, so let me know if I'm violating any etiquette/cultural guidelines or if you have any formatting tips.

I've just upgraded my gemini to android 8.1 and managed to preserve root and my data, here's a rough outline of how I did it:

- full nandroid backup from TWRP, copied to another computer of course
- flash a brand-new android-only scatterfile with sp_flashtool from http://support.planetcom.co.uk/partitionTool.html
- go to firmware update, download (but don't install) ota.zip
- copy ota.zip to another computer
- boot into recovery
- flashed ota.zip via adb sideload
- restored system+data from backup, had to reformat /data to make it big enough to fit my backup
- flashed ota.zip again via sideload -- I'm sure there's a better way to do this?
- flashed magisk from sideload

I've tried a bunch of different recovery.img for mt6797 in flashtool, TWRP just doesn't seem to want to boot with android 8.1. Next step is to hook up an FTDI cable and see why >_>

if someone were to ask me how to upgrade to 8.1 now, after 2 days of trying various things, my recommended procedure would be:

- full nandroid backup
- download ota.zip via update manager
- flash ota.zip from adb sideload in twrp
- flash magisk.zip

No guarantees this will work, though, and I wanted to document my process.