Android NXP Guide

From Variscite Wiki
VAR-SOM-MX8 - Android Pie P9.0.0_r30 Developer Guide

1 Introduction

This Wiki describes how to build and deploy Android Pie on the VAR-SOM-MX8. It is based on NXP's imx_9.0.0_2.0.0_ga_ANDROID release

2 Overview

The objective of this document is to guide VAR-SOM-MX8 Android developers to obtain Android Pie sources, setting up host environment, compilation, and deployment.

This document contains instructions for:

  • Hardware and software requirements.
  • Setup the hardware.
  • Setup the toolchain.
  • Download & build the sources.
  • Install the binaries on the VAR-SOM-MX8 SOM and variants.

3 Supported hardware and features

SOM support
Carrier Board support
Symphony Board (VAR-SOM-MX8 only) VAR-SP8CustomBoard (SPEAR-MX8 only)


up to 64GB
LPDDR4 size support configuration
up to 8GB
SD card
Wired Network
10/100/1000 Mbps Ethernet
Wireless Network
Support for LWB5, 802.11 ac/a/b/g/n STA, AP, & Wi-Fi Direct Mode SmartConfig
4.2 / BLE
USB host
Host and Device
x4, up to 4 Mbps.
Display LVDS Dual 1920×1080 24-bit
MIPI-DSI 1920×1080 24-bit
HDMI V2.0a up to 4Kp60
eDP1.4/DP1.3 up to 4Kp60
Audio Line IN / HP
Camera 2x MIPI-CSI2

4 Hardware Requirements

You will need the Variscite VAR-SOM-MX8 based evaluation kit.

4.1 Host (PC) setup requirements

The host development environment for Android is based on Ubuntu, please install Ubuntu version 16.04/18.04 64bit LTS

If you are running Linux in a virtual machine you need at least 16GB of RAM/swap.

Note: Do not use other Ubuntu releases other than the ones recommended above.

4.1.1 Install required packages on host PC

$ sudo apt-get -y install gnupg flex bison gperf build-essential zip gcc-multilib g++-multilib 
$ sudo apt-get -y install libc6-dev-i386 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z-dev
$ sudo apt-get -y install ccache libgl1-mesa-dev libxml2-utils xsltproc unzip bc
$ sudo apt-get -y install uuid uuid-dev zlib1g-dev liblz-dev liblzo2-2 liblzo2-dev lzop git curl
$ sudo apt-get -y install u-boot-tools mtd-utils android-tools-fsutils device-tree-compiler gdisk m4 libz-dev

4.1.2 Configure Git

$ git config --global "Your Name"
$ git config --global "Your Email"

4.1.3 Install the OpenJDK

To install it:

$ sudo apt-get update
$ sudo apt-get install openjdk-8-jdk

If your Ubuntu version is missing the package (which shouldn't happen), add the PPA repository and run the previous commands again:

$ sudo add-apt-repository ppa:openjdk-r/ppa

Update the default Java version by running:

$ sudo update-alternatives --config java
$ sudo update-alternatives --config javac

Note: The build process requires about 135GB of free space.

5 Obtain source code

Variscite's Linux kernel and U-Boot are available through Github.
Required patches for the Android file system are under: in Variscite's FTP


  • imx-p9.0.0_2.0.0-ga.tar.gz - NXP's i.MX8M p9.0.0_2.0.0_ga original BSP patch files.

5.1 Get NXP's Android Release Package

$ mkdir ~/var_imx-p9.0.0_2.0.0-ga
$ cd ~/var_imx-p9.0.0_2.0.0-ga
$ curl -o ~/Downloads/imx-p9.0.0_2.0.0-ga.tar.gz
$ tar xvf ~/Downloads/imx-p9.0.0_2.0.0-ga.tar.gz

5.2 Download Google Android P9.0.0_r30

$ mkdir -p ~/bin
$ curl -o ~/bin/repo
$ chmod a+x ~/bin/repo
$ export PATH=~/bin:$PATH
$ cd ~/var_imx-p9.0.0_2.0.0-ga
$ source imx-p9.0.0_2.0.0-ga/

Wait for the script to finish running, and it should create a "~/var_imx-p9.0.0_2.0.0-ga/android_build" folder

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build; mkdir -p vendor/variscite/

5.3 Clone Variscite's U-Boot and Linux kernel sources

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build/vendor/variscite/
$ git clone -b imx_v2018.03_4.14.98_2.0.0_ga_var01
$ git clone kernel_imx -b p9.0.0_2.0.0-ga_var01

5.4 Apply Variscite's i.MX platforms patches

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build/device
$ git clone -b p9.0.0_2.0.0-ga-var01 variscite
$ variscite/scripts/

6 Build Android Images

Change to Android top level directory.

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build
$ source build/
$ lunch som_mx8qm-eng
$ lunch som_mx8qm-userdebug

Note: userdebug build creates a debuggable version of Android. eng build creates an engineering version of Android. Development mode enable and development tools are available on target.

$ export PATH=/usr/lib/jvm/java-8-openjdk-amd64/bin:$PATH

6.1 Switching from eMMC build to SD card build and vice versa

Unlike previous Android BSPs, the boot media is autodetected at boot time.

6.2 Build Android

$ make -j4 2>&1 | tee build1-1.log

6.3 Images created by the Android build

The resulted images are located in out/target/product/som_mx8q.

u-boot-imx8qm.imx U-Boot for eMMC/SD card boot.
SOM agnostics.
boot.img Android kernel image file.
SOM agnostics.
system.img Android system image file.
SOM agnostics.
vendor.img Android vendor image file.
SOM agnostics.
configuration dependent
where <name> can be: imx8qm-var-som-dp - Supports VAR-SOM-MX8 with DP
imx8qm-var-som-hdmi - Supports VAR-SOM-MX8 with HDMI
imx8qm-var-som-lvds - Supports VAR-SOM-MX8 with LVDS
imx8qm-var-spear-dp - Supports SPEAR-MX8 with DP
imx8qm-var-spear-hdmi - Supports SPEAR-MX8 with HDMI
imx8qm-var-spear-lvds - Supports SPEAR-MX8 with LVDS

7 Boot options

Boot options of the Android:
1. Directly from SD card
2. U-Boot boots from on-SOM eMMC

7.1 Flash and boot Android from SD card

7.1.1 Create a bootable SD card

Partition and format SD card, and copy all images

$ sudo ./ -f <name> /dev/sdX;sync

7.1.2 Boot From SD card

  • Power-off the board.
  • Insert the SD card into the SD card slot of the carrier board (DVK)
  • Make sure the Boot Mode is set to SD card: see Setting the Boot Mode section
  • Power up the board - it will boot into Linux from the SD card

7.2 Flash and boot Android from eMMC

7.2.1 Preparing images

The default system.img and vendor.img format is suitable for flashing using fastboot, and must be modified for flashing using 'dd'.

$ cd out/target/product/som_mx8q
$ simg2img system.img system_raw.img
$ simg2img vendor.img vendor_raw.img

7.2.2 Flashing Android from Linux shell (when the primary installation android)

An example of flashing eMMC, can be found here.

Follow the following steps instructions above:

1. Preparing a rescue SD card;

2. Flash from command line (use the script)

Further, follow the steps described in paragraph "Flashing Android with USB Fastboot"

7.2.3 Flashing Android with USB Fastboot Install tools on host

$ sudo apt-get install android-tools-adb android-tools-fastboot

Note: Make sure you built Android for eMMC
Connect the target with host PC at fastboot mode:

  1. Connect a USB OTG cable from the target board OTG port to a your host machine USB HOST port.
  2. Power up the board and hit return/space to stop the boot at U-Boot.
  3. type fastboot q in the U-Boot command line.

On the Host PC:

$ sudo `which fastboot` flash dtbo_a out/target/product/som_mx8q/dtbo-<name>.img
$ sudo `which fastboot` flash dtbo_b out/target/product/som_mx8q/dtbo-<name>.img
$ sudo `which fastboot` flash boot_a out/target/product/som_mx8q/boot.img
$ sudo `which fastboot` flash boot_b out/target/product/som_mx8q/boot.img
$ sudo `which fastboot` flash system_a out/target/product/som_mx8q/system.img
$ sudo `which fastboot` flash system_b out/target/product/som_mx8q/system.img
$ sudo `which fastboot` flash vendor_a out/target/product/som_mx8q/vendor.img
$ sudo `which fastboot` flash vendor_b out/target/product/som_mx8q/vendor.img
$ sudo `which fastboot` flash vbmeta_a out/target/product/som_mx8q/vbmeta-<name>.img
$ sudo `which fastboot` flash vbmeta_b out/target/product/som_mx8q/vbmeta-<name>.img
$ sudo `which fastboot` reboot

Replace <name> with the actual desired setup name according to the table in the "Images created by the Android build" section.

7.2.4 Android recovery mode Enter board in Android Recovery mode

If you are using DT8MCustomBoard or you implemented any recovery key detection in uboot, the device can powered on in recovery mode by holding down the "back" (or any other recovery key) button until the end of the boot, showing the "Android Recovery" menu.

Alternatively you can issue the command reboot recovery from the Android console (or using adb shell). Control menu in Android Recovery Mode

If the board has UP, DOWN keys (like DT8MCustomBoard)

  1. To cycle between menu items, use a short press of UP or DOWN buttons
  2. To highlight an item, use a long press of BACK or HOME buttons or long touch the touchscreen
  3. To activate an item, use a short press of ON/OFF button

If the board has no UP and DOWN keys (like SymphonyBoard)

  1. To cycle between menu items, use a short press of any buttons or select the item with the touchscreen
  2. To activate an item, use a long press of any buttons or of the touchscreen Update Android firmware Generate OTA packages

For generating "OTA" packages, use the following commands:

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build
$ make PRODUCT=som_mx8qm-eng otapackage -j4 2>&1 Install OTA package to device
  • extract payload.bin and payload_properties.txt from OTA zip file
  • push file payload.bin to somewhere on the device (typically /cache folder)
  • open payload_properties.txt on an editor to copy its content, lets suppose it's like in the NXP manual:
  • Issue the following command on adb shell:
 update_engine_client --payload=file:///cache/payload.bin --update --headers="FILE_HASH=0fSBbXonyTjaAzMpwTBgM9AVtlBeyOigpCCgkoOfHKY=

Note that the command argument --headers="..." contains the exact (4-line) content of the payload_properties.txt file between quotes (you can copy and paste it), including 3 newline characters.

After issuing the command, nothing seems to happen on the device, but you can monit logcat for operation progress. After a successful update you can reboot into the updated version.

You can check chapter 7 of official NXP "Android User Guide" for further "Over-The-Air (OTA) Update" examples.

8 Manual operations

8.1 Build boot.img

When you perform changes to the kernel, you may build boot.img solely instead of building the whole Android.

$ cd ~/var_imx-p9.0.0_2.0.0-ga/android_build
$ source build/
$ lunch som_mx8qm-userdebug
$ make bootimage

8.2 Toolchain setup for manual build

Setup the toolchain path to point to arm-linux-androideabi- tools in prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/bin

$ export ARCH=arm64
$ export CROSS_COMPILE=~/var_imx-p9.0.0_2.0.0-ga/android_build/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/bin/aarch64-linux-android-

8.3 Unlock device for fastboot

Our build behaves like any other standard Android device.

To use fastboot, you should go through the following steps

  • Settings => System => About Tablet => Build number
  • keep on tapping until you see a prompt that says "You are now a developer!"
  • Settings => System => Advanced => Developer options => OEM unlocking
  • reboot to bootloader
  • type "fastboot 0" in the U-Boot command line
  • run "sudo `which fastboot` oem unlock" from the Host PC
  • wait until the unlock process is complete
  • proceed for flashing