Note: Some of these notes were saved in a draft and going off of memory. May not be entirely complete.
Basic steps to flash the factory Android image back onto a Google Pixel 1
You can download the full OTA image from
https://developers.google.com/android/ota
Go to https://twrp.me/Devices and download the correct version TWRP for your device.
Boot into boot loader menu
Plug you phone into a computer that has fastboot installed and run
sudo fastboot boot Downloads/twrp-3.3.0-0-sailfish.img
Note you may need to unlock your boot loader.
Your phone should now boot up into TWRP
Swipe to Allow Modifications
Select advanced
Then hit ADB Sideload.
Swipe to start the sideload and then sideload from your computer
adb sideload image.zip
More detailed explaination
https://www.cyanogenmods.org/adb-sideload-twrp/
To boot up into the Android boot menu, start by powering down phone.
Once it is powered off, press the Volume Down and Power button and hold until it turns on.
You should get the boot menu.
Installing GrapheneOS is pretty well documented on the website.
https://grapheneos.org/install
The following are mainly some of my notes. More detailed instructions are available at the above link.
To enable the developer options on Android go to Settings -> About phone -> Tap on Build number until it says your a Developer.
Settings -> System -> Advanced (Dropdown) -> Developer options
Allow OEM unlocking
Boot into the bootloader By
Run the following command from a computer with fastboot
sudo fastboot flashing unlock
The screen should change, hit the arrow keys to select Unlock the bootloader and confirm with the power button
Download the proper factory image and files from https://grapheneos.org/releases
The name should say something device-factory-date.zip and device-factory-date.zip.sig
The .sig file is used to verify the image in the below section.
Verify the Keys
The commands to do this are from a Linux computer. There may be alternatives for Windows. You can technically skip this section.
Install signify
sudo apt install signify-openbsd -y
Download the public key from https://releases.grapheneos.org/factory.pub
Run and check that the key and the image match.
The following command assumes you are in the same directory as the image and factory.pub file.
sudo signify-openbsd -Cqp factory.pub -x blueline-factory-2020.03.04.16.zip.sig && echo verified
Unzip the factory image and change directories into it
unzip blueline-factory-2020.03.04.16.zip && cd blueline-qq2a.200305.002/
Run the flash script to flash the image to your Pixel.
sudo ./flash-all.sh
Wait for it to flash, may take a long time.
NOTE: I ran into issues with the script as my version of fastboot was old. SEE PROBLEMS HEADING BELOW
Boot back up into the recovery menu and lock the boot loader with
fastboot flashing lock
On the phone enable Developer options. More info here.
Find the “OEM unlocking” button and enable.
Reboot phone to bootloader.
Plug phone into computer and computer run
sudo fastboot flashing unlock
Use the buttons on the phone to select and enable unlocking.
To enable the developer options on Android go to Settings -> About phone -> Tap on Build number until it says your a Developer.
Now you can go to Settings -> System -> Advanced -> Developer options to edit developer settings.
Download LineageOS
Download the unofficial LineageOS 16 build from the following page
https://konstakang.com/devices/rpi3/LineageOS16.0/
Unzip
Unzip the file with
unzip ~/Downloads/lineage-16.0-20200207-UNOFFICIAL-KonstaKANG-rpi3.zip
Write to SD Card
Either use the instructions on the following link to write it to the SD card
https://www.raspberrypi.org/documentation/installation/installing-images/windows.md
Or use DD
WARNING! Make sure “/dev/mmcblk0” is the correct SD Card. Refer to here if you need to locate the path for the SD Card.
sudo dd if=~/Downloads/lineage-16.0-20200207-UNOFFICIAL-KonstaKANG-rpi3.img of=/dev/mmcblk0 bs=1M status=progress
Plug you SD Card into your Pi and boot it up.
Download twrp from here
Download LineageOS 17 from here
Boot phone to boot menu then fastboot twrp
sudo fastboot boot Downloads/twrp-3.3.0-0-sailfish.img
Wipe to factory defaults
Side load LineageOS Android 10 from the Advanced page on TWRP
adb sideload Downloads/lineage-17.0-withMTG-20191217-UNOFFICIAL-sailfish.zip
Reboot and setup.
Command from here
https://android.stackexchange.com/a/78183/239063
From a command line run
( printf "\x1f\x8b\x08\x00\x00\x00\x00\x00" ; tail -c +25 ~/Path/to/android_backup.ab ) | tar xfvz -
https://stackoverflow.com/questions/18533567/how-to-extract-or-unpack-an-ab-file-android-backup-file
Install Android Backup Toolkit
wget https://downloads.sourceforge.net/project/adbextractor/android-backup-tookit-20180521.zip unzip android-backup-tookit-20180521.zip cd android-backup-tookit/android-backup-extractor/android-backup-extractor-20180521-bin
Unpack backup. Changes it from an ab to a tar file
java -jar abe.jar unpack ~/path/to/backup.ab ~/path/to/backup.tar
After thats complete, you can untar it. Change Desktop to the path you want to extract to.
tar -xvf ~/path/to/backup.tar -C ~/Desktop/