AOSP on Pixel3 running Mainline kernel

Not to be confused with AOSP's aosp_blueline-userdebug build target, goal of this project is to run AOSP on Pixel3 device with mainline linux kernel.

  • Upstream aosp_blueline-userdebug build target use Qcom prebuilt firmware and services binaries which only work with msm-android-4.9 kernel.
  • pixel3_mainline-userdebug build target use mainline linux kernel and can boot to 'UI' right now with ADB - with garbled screen. Work is going on to enable DSC for the Display panel.

Compile AOSP and kernel image from sources for pixel3_mainline

1. Download the AOSP source tree and build pixel3_mainline target:

repo init -u -b master
repo sync -j`nproc`
source ./build/
lunch pixel3_mainline-userdebug
make -j`nproc`

2. Download Android9.0 stock image from, and run This ensures the currenly verified working bootloader is installed.

Verify that the bootloader version shows

ABL version: b1c1-0.1-5034669
ABL build time: Sep 27 2018 17:15:40

3. Extract Adreno firmware from stock images

  • Unzip found in the stock image downloaded in step 2.
  • Extract vendor.img, and convert it to a mountable raw image.

out/host/linux-x86/bin/simg2img vendor.img vendor.raw

  • Mount vendor.raw and extract graphics firmware

mkdir mnt; sudo mount mnt vendor.raw
mkdir $ANDROID_BASE_DIR/device/linaro/dragonboard/pixel3_mainline/firmware
cp mnt/firmware/a630*
  • Copy firmware/

-O $ANDROID_BASE_DIR/device/linaro/dragonboard/pixel3_mainline/firmware/

4. Build kernel image and boot.img:

  • Run the following commands to clone and build kernel Image:

git clone -b dev/p3-mainline-WIP
cd linux
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- blueline_defconfig
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- Image.gz qcom/sdm845-blueline.dtb -j`nproc`
cat arch/arm64/boot/Image.gz arch/arm64/boot/dts/qcom/sdm845-blueline.dtb > Image.gz-dtb
  • Build boot.img by running following mkbootimg command:

mkbootimg --kernel Image.gz-dtb --ramdisk \
out/target/product/pixel3_mainline/ramdisk.img \
--base 0x00000000 --pagesize 4096 \
--cmdline "" --output boot.img
  • where ramdisk.img is created as part of AOSP build for pixel3_mainline-userdebug.

Note: cmdline is hardcoded in kernel config (blueline_defconfig) so that bootloader appended bootargs do not crash our boot.

  1. Install:

Boot Pixel3 in fastboot mode by powering off the device and then hold VOL down button and press/hold POWER button until bootloader (fastboot) comes up. Download and unzip vbmeta.img from Pixel3 factory images, which is used to disable image verification. And then run following commands from HOST machine while Pixel3 is still booted in fastboot mode:

# unlock bootloader
fastboot oem unlock

# disable image verification if you haven't already
fastboot --disable-verity --disable-verification flash vbmeta_a vbmeta.img
fastboot --disable-verity --disable-verification flash vbmeta_b vbmeta.img

# set _b as active partition since we mount system_b as super partition
fastboot set_active b

# flash AOSP images and reboot
fastboot flash system out/target/product/pixel3_mainline/super.img
fastboot flash userdata out/target/product/pixel3_mainline/userdata.img
fastboot flash boot boot.img
fastboot reboot

# login to Android console
adb shell

ToDo / Known Issues

  • fastboot boot boot.img is broken

  • Android 10 bootloaders don't yet work
  • Display is WIP - we get to a garbled UI, and Android reports boot_completed; DSC support enablement is in-progress to allow proper UI.
  • bootctrl HAL is WIP. So if you run into FAILED (remote: 'Failed to load/authenticate boot image: Load Error'), then run following command:

fastboot fastboot set_active b

Need some help?

In addition to this wiki, we use various mailing lists, IRC, and to communicate.

  • LCG's public mailing lists
  • IRC via
    • #linaro-android
    • #linaro-lmg

You can use the web or your favourite IRC client.

AOSP/blueline (last modified 2020-03-29 15:56:25)