Android: Getting up and running on the iMX6

Published

Getting Android up and running on the iMX6 platform using an open source graphics stack has been impossible up until recently, but now you can. Here's a guide through the steps.

Since the hardware very much matters this is going to be divided into a few parts, the common steps and the hardware specific ones.

This post is a bit of a living document and will be changed over time, and if you have any questions about it, please reach out through email (robert.foss at collabora.com) or irc (tomeu or robertfoss on #dri-devel on freenode).

Changelog:
2017-04-27: build_android.sh, setup_sdcard.sh: Added -b [device] support to build_android.sh and setup_sdcard.sh
2017-05-02: build_android.sh: Don't write to SD-card without -b option
2017-05-04: Switch git repo urls to shared repository
2017-05-09: Add compiler installation to apt-get
2017-05-09: Re-ordered some instructions
2017-05-10: Add java installation to apt-get
2017-05-19: Change paths to android-etnaviv instead of client
2017-05-19: Change kernel branch
2017-05-19: Add -d, device flag and info about it
2017-05-19: Add sabrelite board info

Common steps

# Install mkimage tool from u-boot and a suitable compiler
sudo apt install u-boot-tools gcc-arm-linux-gnueabihf openjdk-8-jdk

mkdir /opt/android
repo init -u https://android.googlesource.com/platform/manifest -b android-7.1.1_r28
cd /opt/android/.repo
git clone https://customer-git.collabora.com/git/android-etnaviv/android_manifest.git local_manifests -b android-etnaviv
repo sync -j10

mkdir /opt/imx6_android
cd /opt/imx6_android

# Fetch Kconfig, bootloaders and some scripts
git clone https://customer-git.collabora.com/git/android-etnaviv/android-etnaviv.git .

# Fetch the Linux Kernel
git clone https://customer-git.collabora.com/git/android-etnaviv/linux.git -b android-etnaviv

# This will destroy all data on /dev/mmcblk0 and
# create boot/system/cache/data partitions
./setup_sdcard.sh -b /dev/mmcblk0

Hardware: iMX6 Sabre

Build Android and Linux

# Build android, the kernel, and flash it onto an SD-card
# Run build_android with the correct -d flag
./build_android.sh -b /dev/mmcblk0 -d imx6q-sabre
./build_android.sh -b /dev/mmcblk0 -d imx6qp-sabre

Start Android

The SD-card can now be put into the SD3 slot and the device can be restarted.

Hardware: iMX6 Sabrelite

Build Android and Linux

# Build android, the kernel, and flash it onto an SD-card
# Run build_android with the correct -d flag
./build_android.sh -b /dev/mmcblk0 -d imx6q-sabrelite

Start Android

The micro-sd card can now be put into the micro-sd slot and the device can be restarted.

Hardware: RDU2

Build Android and Linux

# Build android, the kernel, and flash it onto an SD-card
# Run build_android with the correct -d flag
./build_android.sh -b /dev/mmcblk0 -d imx6q-zii-rdu2
./build_android.sh -b /dev/mmcblk0 -d imx6qp-zii-rdu2

Install the bootloader

# Depending if you have a >=13" version of the RDU2
# use the imx6qp, if <13" then use the imx6q

IMX6_TYPE=imx6q
IMX6_TYPE=imx6qp
BAREBOX="zodiac/barebox-zii-${IMX6_TYPE}-rdu2.img"

# Flash bootloader to SD-card
dd if=${BAREBOX} of=/dev/mmcblk0 bs=1k
sync

# Put SD-card in the middle-most slot on the RDU2

# Install lrzsz, since it is used for a ymodem upload
sudo apt install lrzsz

# Connect to serial device /dev/ttyUSB2 and
# /dev/ttyUSB3 with minicom
# The numbering assumes the RDU2 is the only serial
# serial device connected
sudo minicom -s
    +------------------------------------------+
    | A -    Serial Device      : /dev/ttyUSB3
    | B - Lockfile Location     : /var/lock
    | C -   Callin Program      :
    | D -  Callout Program      :
    | E -    Bps/Par/Bits       : 115200 8N1
    | F - Hardware Flow Control : No
    | G - Software Flow Control : No
    |
    |    Change which setting?
    +------------------------------------------+

# Connect to Quark console on /dev/ttyUSB3
# Set boot SD-card as boot source 
#HostBoot s 0
reset

# Restart device, connect to barebox loaded just loaded
# from the SD-card on /dev/ttyUSB2
pic_setwdt 0 60
loady

# Using the minicom quickly initiate a ymodem file
# of the same barebox image you wrote to the SD-card
# Be quick, the upload will timeout after a few seconds

# Write the bootloader to SPI NOR
erase /dev/m25p0.barebox
# Depending on your RDU2 type flash one of the following
cp barebox-zii-imx6q-rdu2.img /dev/m25p0.barebox
# Or
cp barebox-zii-imx6qp-rdu2.img /dev/m25p0.barebox

# Connect to the Quark console on /dev/ttyUSB3 again
# Set SPI NOR as the boot source
#HostBoot s 2
reset

# Connect to the barebox console on /dev/ttyUSB2 again
# Edit configuration to automatically boot from mmc:
sedit /env/config
export global.boot.default=/env/boot/mmc
export global.bootm.image=/mnt/mmc1.0/android_zImage
export global.bootm.initrd=/mnt/mmc1.0/android_ramdisk.img.gz
export global.bootm.oftree=/mnt/mmc1.0/imx6qp-zii-rdu2.dtb
export global.linux.bootargs.base="console=ttymxc0,115200 console=tty0 rw rootwait ip=dhcp buildvariant=userdebug debug ignore_loglevel root=/dev/mmcblk0p2 rootfstype=ext4 rootwait init=/init printk.devkmsg=on verbose enforcing=0 androidboot.selinux=permissive drm.debug=0x00"

sedit /env/boot/mmc
#!/bin/sh
detect mmc1
mkdir -p /mnt/mmc1.0
automount -d /mnt/mmc1.0 'mount /dev/mmc1.0 /mnt/mmc1.0'
bootm

pic_setwdt 0 60     # Disable watchdog

exit

Start Android

The SD-card created in the common steps can now be put into the middlemost slot and the device can be restarted.

Thanks

This work is built on efforts by a lot people:

This post has been a part of work undertaken by my employer Collabora.

Tags: android · aosp · imx6 · sabre · rdu2 · vivante · etnaviv · linux · collabora