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Android 15.0.0_1.2.0 Developer Guide

Introduction

This page explains how to build and deploy Android Android 15 on the VAR-SOM-MX8M-NANO.

This release is based on NXP's i.MX android-15.0.0_1.2.0 release.

For additional details about this release, refer to the Release Notes.

Overview

The objective of this document is to guide VAR-SOM-MX8M-NANO Android developers to obtain Android Android 15 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-MX8M-NANO SOM and variants.

Hardware Requirements

You will need the Variscite VAR-SOM-MX8M-NANO based evaluation kit.

Host (PC) setup requirements

The host development environment for Android is based on Ubuntu, please install one of the following Ubuntu versions:

If you are running Linux in a virtual machine you need at least 16GB of RAM and 32 GB of swap. The build process requires ~250GB of free storage space. Before starting a build, make sure you have adequate free space available.

Note: Do not use other Ubuntu releases other than the ones recommended above. Variscite provides Docker containers that can be used for a development environment as an alternative to using a virtual machine or a dedicated computer.

To learn more, please see Variscite's Docker Build Environment guide.

Windows with WSL/WSL2 is not supported for Android BSP

Install required packages on host PC

 $ sudo apt-get update && sudo apt-get dist-upgrade

Then, install the following packages:

 $ sudo apt-get install python3 python3-pip python3-pexpect \
 python3-git python3-jinja2 python3-subunit python3-git liblz4-tool \
 python3-jinja2 python3-subunit curl zstd

For Ubuntu 20.04 and earlier, install python2:

sudo apt-get install python python-pysqlite2

Starting in Ubuntu 22.04, python2 is no longer available. Install the following to create a symbolic link from python to python3:

sudo apt-get install python-is-python3

Ubuntu 24.04 introduced additional unprivileged user namespace restrictions. They must be disabled to avoid permission errors during Yocto fetch tasks when using Variscite's docker container.

Disable this restriction on the entire system for one boot:

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

Alternatively, disable this restriction using a persistent setting by adding a new file (/etc/sysctl.d/60-apparmor-namespace.conf) with the following contents:

echo 'kernel.apparmor_restrict_unprivileged_userns=0' | sudo tee /etc/sysctl.d/60-apparmor-namespace.conf
sudo sysctl -p /etc/sysctl.d/60-apparmor-namespace.conf

Install Docker:

sudo apt update && sudo apt install docker.io qemu-user-static

Give permissions to run Docker without sudo:

sudo usermod -aG docker ${USER}
# Logout and login again for the permissions to take effect.

Configure git user and email:

git config --global user.name "Your Name"
git config --global user.email "Your Email"

Obtain source code

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

Files:

Get NXP's Android Release Package

mkdir ~/var_imx-android-15.0.0_1.2.0
cd ~/var_imx-android-15.0.0_1.2.0
curl -o ~/Downloads/imx-android-15.0.0_1.2.0.tar.gz https://variscite-public.nyc3.cdn.digitaloceanspaces.com/Android/Android_iMX8_1500_120/imx-android-15.0.0_1.2.0.tar.gz
tar xvf ~/Downloads/imx-android-15.0.0_1.2.0.tar.gz

Sync Android Source

mkdir -p ~/bin
curl -o ~/bin/repo https://commondatastorage.googleapis.com/git-repo-downloads/repo
chmod a+x ~/bin/repo
export PATH=~/bin:$PATH
cd ~/var_imx-android-15.0.0_1.2.0
source imx-android-15.0.0_1.2.0/imx_android_setup.sh

Note: Wait for the script to finish running, and it should create following folders

~/var_imx-android-15.0.0_1.2.0/android_build/device/variscite/
~/var_imx-android-15.0.0_1.2.0/android_build/vendor/variscite/kernel_imx and
~/var_imx-android-15.0.0_1.2.0/android_build/vendor/variscite/uboot-imx

Apply Variscite's i.MX platforms patches

cd ~/var_imx-android-15.0.0_1.2.0/android_build/device
variscite/scripts/install.sh

Build Android Images

Start a Ubuntu Docker container:

cd ~/var_imx-android-15.0.0_1.2.0/android_build/
./var-start-container.sh

Note: After Ubuntu Docker container is started you can see the shell prompt similar to: vari@20-04-3b61eb74-android-15-0-0_1-2-0$

All references to commands without this prompt should be executed in a native terminal (outside Docker). If you need to run a command using 'sudo' inside the container, the default password is ubuntu.

Change to Android top level directory.

source build/envsetup.sh
lunch som_mx8mn-user

or

lunch som_mx8mn-userdebug

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

user build variant creates a production version of Android.

Switching from eMMC build to SD card build and vice versa

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

Build Android

./imx-make.sh -j4 2>&1 | tee build1-1.log
Note: To build Android images for VAR-SOM-MX8M-NANO V1.x

TARGET_USES_BCM_WIFI=true ./imx-make.sh -j4 2>&1 | tee build1-1.log

Images created by the Android build

The resulted images are located in out/target/product/som_mx8mn.

Image
Description
u-boot-imx8mn-var-som.imx U-Boot image without Trusty OS integrated for eMMC/SD card boot.
Used for sigle-bootloader condition.
u-boot-imx8mn-var-som-uuu.imx U-Boot image for uuu USB boot.
spl-imx8mn-var-som-dual.bin SPL image without Trusty for eMMC/SD card boot.
Used for dual-bootloader condition.
bootloader-imx8mn-var-som-dual.img Bootloader image without Trusty OS integrated for eMMC/SD card boot.
Used for dual-bootloader condition.
boot.img Android kernel image file.
vendor_boot.img A composite image, which includes another part of ramdisk and boot parameters.
init_boot.img A composite image, which includes init process.
super.img Android super image file.
dtbo-<name>.img
vbmeta-<name>.img 		configuration dependent
<name> is: imx8mn-var-som-1.x-symphony - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V1.x on a Symphony-Board)
imx8mn-var-som-symphony - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V2.x on a Symphony-Board V2.x)

imx8mn-var-som-1.x-symphony-m7 - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V1.x on a Symphony-Board) with Cortex M7

imx8mn-var-som-symphony-m7 - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V2.x on a Symphony-Board V2.x) with Cortex M7

imx8mn-var-som-1.x-symphony-1.x - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V1.x on a Symphony-Board V1.x)

imx8mn-var-som-1.x-symphony-1.x-m7 - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V1.x on a Symphony-Board V1.x) with Cortex M7

imx8mn-var-som-symphony-1.x - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V2.x on a Symphony-Board V1.x)

imx8mn-var-som-symphony-1.x-m7 - Supports LVDS / SD / WIFI (VAR-SOM-MX8M-NANO V2.x on a Symphony-Board V1.x) with Cortex M7

dtbo-imx8mn-var-som-wbe-symphony-m7.img - VAR-SOM-MX8M-NANO V2.x with WBE on Symphony-Board V2.x with M7 support

dtbo-imx8mn-var-som-wbe-symphony.img - VAR-SOM-MX8M-NANO V2.x with WBE on Symphony-Board V2.x

dtbo-imx8mn-var-som-wbe-symphony-1.x-m7.img - VAR-SOM-MX8M-NANO V2.x with WBE on Symphony-Board V1.x with M7 support

dtbo-imx8mn-var-som-wbe-symphony-1.x.img - VAR-SOM-MX8M-NANO V2.x with WBE on Symphony-Board V1.x

dtbo-imx8mn-var-som-symphony-m7.img - VAR-SOM-MX8M-NANO V2.x on Symphony-Board V2.x with M7 support

dtbo-imx8mn-var-som-symphony.img - VAR-SOM-MX8M-NANO V2.x on Symphony-Board V2.x

dtbo-imx8mn-var-som-symphony-1.x-m7.img - VAR-SOM-MX8M-NANO V2.x on Symphony-Board V1.x with M7 support

dtbo-imx8mn-var-som-symphony-1.x.img - VAR-SOM-MX8M-NANO V2.x on Symphony-Board V1.x

dtbo-imx8mn-var-som-1.x-symphony-m7.img - VAR-SOM-MX8M-NANO V1.x on Symphony-Board V2.x with M7 support

dtbo-imx8mn-var-som-1.x-symphony.img - VAR-SOM-MX8M-NANO V1.x on Symphony-Board V2.x

dtbo-imx8mn-var-som-1.x-symphony-1.x-m7.img - VAR-SOM-MX8M-NANO V1.x on Symphony-Board V1.x with M7 support

dtbo-imx8mn-var-som-1.x-symphony-1.x.img - VAR-SOM-MX8M-NANO V1.x on Symphony-Board V1.x

Boot options

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

Flash and boot Android from SD card

Create a bootable SD card

Partition and format SD card, and copy all images

sudo ./var-mksdcard.sh -f <name> /dev/sdX;sync

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
  • Power up the board - it will boot into Linux from the SD card

Flash and boot Android from eMMC

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_mx8mn
simg2img system.img system_raw.img
simg2img vendor.img vendor_raw.img

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 install_android.sh script)

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

Flashing Android with USB Fastboot

Install android tools on host machine
sudo apt-get install android-tools-adb android-tools-fastboot

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 0 in the U-Boot command line.

On the Host PC:

sudo `which fastboot` flash bootloader_a out/target/product/som_mx8mn/bootloader-imx8mn-var-som-dual.img
sudo `which fastboot` flash bootloader_b out/target/product/som_mx8mn/bootloader-imx8mn-var-som-dual.img
sudo `which fastboot` flash dtbo_a out/target/product/som_mx8mn/dtbo-<name>.img
sudo `which fastboot` flash dtbo_b out/target/product/som_mx8mn/dtbo-<name>.img
sudo `which fastboot` flash boot_a out/target/product/som_mx8mn/boot.img
sudo `which fastboot` flash boot_b out/target/product/som_mx8mn/boot.img
sudo `which fastboot` flash init_boot_a out/target/product/som_mx8mn/init_boot.img
sudo `which fastboot` flash init_boot_b out/target/product/som_mx8mn/init_boot.img
sudo `which fastboot` flash vendor_boot_a out/target/product/som_mx8mn/vendor_boot.img
sudo `which fastboot` flash vendor_boot_b out/target/product/som_mx8mn/vendor_boot.img
sudo `which fastboot` flash super out/target/product/som_mx8mn/super.img
sudo `which fastboot` flash vbmeta_a out/target/product/som_mx8mn/vbmeta-<name>.img --disable-verity
sudo `which fastboot` flash vbmeta_b out/target/product/som_mx8mn/vbmeta-<name>.img --disable-verity
sudo `which fastboot` reboot

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

Update Android firmware

Generate OTA packages

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

cd ~/var_imx-android-15.0.0_1.2.0/android_build
source build/envsetup.sh 
lunch som_mx8mn-userdebug
./imx-make.sh bootloader kernel -j4
make 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 the device (typically /data/ota_package folder)

  • Open payload_properties.txt on an editor to copy its content, lets suppose it's like in the NXP manual:
 FILE_HASH=0fSBbXonyTjaAzMpwTBgM9AVtlBeyOigpCCgkoOfHKY=
 FILE_SIZE=379074366
 METADATA_HASH=Icrs3NqoglzyppyCZouWKbo5f08IPokhlUfHDmz77WQ/de8Dgp9zFXt8Fo+Hxccp465uTOvKNsteWU=
 METADATA_SIZE=46866
  • Input the following command on the board's console to update:
 su
 update_engine_client --payload=file:///data/ota_package/payload.bin --update --headers="FILE_HASH=0fSBbXonyTjaAzMpwTBgM9AVtlBeyOigpCCgkoOfHKY=
 FILE_SIZE=379074366
 METADATA_HASH=Icrs3NqoglzyppyCZouWKbo5f08IPokhlUfHDmz77WQ/de8Dgp9zFXt8Fo+Hxccp465uTOvKNsteWU=
 METADATA_SIZE=46866"

Make sure that the -- header equals to the exact content of payload_properties.txt without "space" or "return" character.

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.

For further details, please see Chapter 7 "Over-The-Air (OTA) Update" of the official NXP "Android User Guide".

Manual operations

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-android-15.0.0_1.2.0/android_build
source build/envsetup.sh
lunch som_mx8mn-userdebug

make bootimage

Toolchain setup for manual build

export ARCH=arm64
export CROSS_COMPILE=~/var_imx-android-15.0.0_1.2.0/android_build/prebuilts/gcc/linux-x86/aarch64/gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu/bin/aarch64-none-linux-gnu-

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

Flashing Using NXP MFGTools - UUU (Universal Update Utility)

To flash Android OS without using a recovery SD card, UUU (MFG Tools 3.0) can be used. Please refer to Flashing Android OS using UUU - USB Boot.

Running a M7 demo

When booting from Recovery SD card, please select one of the following options to install Android from the Linux shell:

imx8mn-var-som-symphony-m7.img - (VAR-SOM-MX8M-NANO V2.x M7 LVDS on Symphony-Board)
imx8mn-var-som-1.x-symphony-m7.img - (VAR-SOM-MX8M-NANO V1.x M7 LVDS on Symphony-Board)

Running a demo from Linux

Boot Android to the shell

Increase kernel loglevel while debugging:

sysctl kernel.printk=7
Check the state of the m7, it should be running already by U-Boot

cat /sys/class/remoteproc/remoteproc0/state
If the state is 'running', stop the m7

echo stop > /sys/class/remoteproc/remoteproc0/state
Load new firmware (.elf file must already exist in /vendor/firmware directory), e.g. for PMSG Ping-Pong FreeRTOS RTOS API Demo:

echo cm_rpmsg_lite_pingpong_rtos_linux_remote.elf.debug > /sys/class/remoteproc/remoteproc0/firmware OR
echo cm_rpmsg_lite_pingpong_rtos_linux_remote.elf.ddr_debug > /sys/class/remoteproc/remoteproc0/firmware
as an alternative, for RPMSG String Echo FreeRTOS RTOS API Demo:

cm_rpmsg_lite_str_echo_rtos_imxcm7.elf.debug > /sys/class/remoteproc/remoteproc0/firmware OR
echo cm_rpmsg_lite_str_echo_rtos_imxcm7.elf.ddr_debug > /sys/class/remoteproc/remoteproc0/firmware
Note: elf.debug uses TCM and elf.ddr_debug uses DDR

Change the state to running

echo start > /sys/class/remoteproc/remoteproc0/state

Run demo module

From device shell

su
cd /vendor
insmod imx_rpmsg_pingpong.ko
as an alternative:

su
cd /vendor
insmod imx_rpmsg_tty.ko

Running a demo from U-Boot

If you need to flash a demo image to the mcu_os partition, please refer to the section "Flashing Android with USB Fastboot". Android comes with pre-compiled demo binaries for Cortex-M7. By default, rpmsg_lite_pingpong_rtos_linux_remote.bin will be burned to the mcu_os partition.

Note: The bootmcu command supports demos built to run only from TCM.

cm_rpmsg_lite_pingpong_rtos_linux_remote.bin.debug - TCM - RPMSG Ping-Pong FreeRTOS RTOS API Demo
cm_rpmsg_lite_str_echo_rtos.bin.debug - TCM - RPMSG String Echo FreeRTOS RTOS API Demo
Run this command:

fastboot flash mcu_os <bin file> from above

When booting, press any key to stop autoboot and enter the U-Boot shell

From U-Boot shell execute the following commands

u-boot=> bootmcu 
run command: 'bootaux 0x7e0000'
## Starting auxiliary core stack = 0x20020000, pc = 0x0000051D...
u-boot=> run bootcmd
Follow steps as described in "Run demo module"

Building Android with Trusty support enabled

Set PRODUCT_IMX_TRUSTY to true in ~/var_imx-android-15.0.0_1.2.0/android_build/device/variscite/imx8m/som_mx8mn/SharedBoardConfig.mk or pass this flag to the make command

PRODUCT_IMX_TRUSTY=true ./imx-make.sh -j4 2>&1 | tee build1-1.log
Follow the instructions from "Build Android Images" section

The images from "Images created by the Android build" section will only be partially different for the bootloader.

Image
Description
spl-imx8mn-var-som-trusty-dual.bin U-Boot SPL with Trusty related configurations for eMMC boot
for Android build with Trusty OS support enabled
to burn only to eMMC
bootloader-imx8mn-var-som-trusty-dual.img An image containing U-Boot proper, ATF and Trusty OS for eMMC boot
for Android build with Trusty OS support enabled
to burn only to eMMC

Follow the instructions from Flashing Android OS using UUU - USB Boot to burn images to eMMC.

Use command list file emmc_burn_android_imx8mn_var_som_symphony_trusty.lst, e.g.:

sudo ./uuu emmc_burn_android_imx8mn_var_som_symphony_trusty.lst