VAR-SOM-MX6 Android GS

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VAR-SOM-MX6 Android-JB-4.2.2 110 r2 DevelopersGuide


This is the second release for VAR-SOM-MX6 Android-JB-4.2.2 110. It includes full Buletooth support on all platforms. Camera support added to the DL and Solo platforms.

The defintion is splited into 3 platforms : Q, DL and Solo to enable better tuning  for som based parameters.


The objective of this document is to guide Android developers to get access to Android JellyBean release sources for VAR-SOM-MX6, setting up host environment for compilation and deployment.

This document contains instructions to:

  • Hardware and software requirement.
  • Setup the hardware.
  • Setup the toolchain.
  • Download & build the sources.
  • Install the binaries on the VAR-SOM-MX6 SOM.

Document Reference

This release is based on Freescale Rev jb4.2.2_1.1.0-GA, 07/2013 release. Please download and read the documents android_jb4.2.2_1.1.0-ga_doc.tar.gz.

  • Android User's Guide
  • Android Quick Start Guide
  • Android Release Notes
  • Android Frequently Asked Questions

Supported hardware and features

Board support

i.MX6 Quad
i.MX6 Dual
i.MX6 Dual lite
i.MX6 Solo

Software platform

Freescale Android-JB-4.2.2 110

Nand Recovery NAND-recovery SD V23 - can be downloaded from FTP
NAND Flash size support
0.5,1.0,2.0 GB
Wired Network
10/100/1000 Mbps Ethernet
Wireless Network
802.11 b/g/n
USB host
Host and Device
x3, up to 3.6 Mbps.
Display HDMI 720P,1080P LVDS0 (On board LVDS to RGB bridge, EVK supports 800x480 resolution) LVDS1 external display
Audio Line IN/ Line out
Camera ov5640 camera sensor. CB402 board can be ordered seperately at :

Variscite Android release for Freescale i.MX6 version Android-JB-4.2.2 110.

Hardware Requirements

VAR-SOM-MX6 evaluation kit.

Host (PC) setup requirements

The host development environment for Android is based on Ubuntu, please install Ubuntu version 12.04 64bit LTS

We recommend you to have a Linux "Ubuntu 12.04 64bit LTS" Host machine.


This DevKit Release was built with 64-bit Ubuntu 12.04. We highly recomend to use this version as your build system.
The host installation would need few more Android specific dependencies, these can be installed dynamically over network using below commands.

For 64-bit Ubuntu 12.04

The complete Android host requirments:

The following command installs the required packages for setting up the android build host:

$ sudo apt-get install libgl1-mesa-dri
$ sudo apt-get install git gnupg flex bison gperf build-essential \
  zip curl libc6-dev libncurses5-dev:i386 x11proto-core-dev \
  libx11-dev:i386 libreadline6-dev:i386 libgl1-mesa-glx:i386 \
  libgl1-mesa-dev g++-multilib mingw32 tofrodos \
  python-markdown libxml2-utils xsltproc zlib1g-dev:i386
$ sudo ln -s /usr/lib/i386-linux-gnu/mesa/ /usr/lib/i386-linux-gnu/

Installing the JDK

The Sun JDK is no longer in Ubuntu's main package repository. In order to download it, you need to add the appropriate repository and indicate to the system which JDK should be used.

Please folow the link for the java install:

Additional packages

In addition to the packages requested on the Android website, the following packages are also required:

$ sudo apt-get install uuid uuid-dev
$ sudo apt-get install zlib1g-dev liblz-dev
$ sudo apt-get install liblzo2-2 liblzo2-dev
The build machine should have at least 30GB of free space to complete the build process.
Please refer to the AOSP documentation for latest information and instructions for setting up other Ubuntu versions

Obtain source code

Variscite provides an Android Release Package for the VAR-SOM-MX6. The Linux kernel and U-Boot are available through GITHUB.

The Android JB installer Package for the VAR-SOM-MX6 can be obtained from Variscite's FTP, under:

  • VAR-SOM-MX6-Android-JB422_110_R3-ReleaseNotes.pdf - Android package release notes.
  • android_jb4.2.2_1.1.0-ga.tar.gz - Freescale's i.MX6 JB4.2.2_110 original patch files.
  • android_jb4.2.2_1.1.0-ga_doc.tar.gz - Freescale i.MX6 JB4.2.2_110 documents
  • repo.tar.gz - A copy of repo tool.
  • var_jb422_110_r3.tar.bz2 - Variscite's VAR-SOM-MX6 SOM patch files

Unpack Freescale's Android Release Package

$ mkdir ~/var_jb_422_110
$ cd ~/var_jb_422_110
$ tar xvf ~/Downloads/android_jb4.2.2_1.1.0-ga.tar.gz 
$ tar xvf android_jb4.2.2_1.1.0-ga_source.tar.gz
$ rm android_jb4.2.2_1.1.0-ga_source.tar.gz
$ rm android_jb4.2.2_1.1.0-ga_tool.tar.gz 

Download Google Android JB4.2.2

The Android source code is maintained in more than 100 different gits in the Android repository (
To get the Android source code from Google repo, follow the steps below:

Assuming you have unzipped the Android release package to ~/var_jb_422_110/android_jb4.2.2_1.1.0-ga_source/.

$ cd ~/var_jb_422_110
$ mkdir jb_422_110_build
$ cd jb_422_110_build
$ mkdir ~/bin
$ curl > ~/bin/repo
$ chmod a+x ~/bin/repo
$ repo init -u -b android-4.2.2_r1
$ repo sync #--> can take a while to complete.
The repo tool which was used by Variscite is available on FTP site.

Download Variscite's u-boot and Linux kernel

clone jb4.2.2_1.1.0-ga kernel source code from Variscite's open source git:

$ cd ~/var_jb_422_110/jb_422_110_build
$ git clone git:// kernel_imx
$ cd kernel_imx
$ git checkout -b jb4.2.2_1.1.0-ga-var13 remotes/origin/jb4.2.2_1.1.0-ga-var13

clone the U-Boot git repository from Varicite's open source git:

$ cd ~/var_jb_422_110/jb_422_110_build/bootable/bootloader
$ git clone git:// uboot-imx
$ cd uboot-imx
$ git checkout -b jb4.2.2_1.1.0-ga.var13 remotes/origin/jb4.2.2_1.1.0-ga.var13
Ig you have a SOM with 0.5GB of ram please apply patch 0001-Check-0.1-GB-ram-and-set-mem-size.patch available on FTP site.

Patching the AFS sources with Freescale i.MX6 support

The patch script ( requires some basic utilities like awk/sed.
Apply all Android patches by using the following steps:
Assuming you have unzipped the Android release package to ~/var_jb_422_110/android_jb4.2.2_1.1.0-ga_source/.

$ cd ~/var_jb_422_110/jb_422_110_build
$ cd ../android_jb4.2.2_1.1.0-ga_source/code/
$ tar xvf jb4.2.2_1.1.0-ga.tar.gz 
$ cd -
$ source ../android_jb4.2.2_1.1.0-ga_source/code/jb4.2.2_1.1.0-ga/
$ help
Now you should see that the "c_patch" function is available
$ c_patch ../android_jb4.2.2_1.1.0-ga_source/code/jb4.2.2_1.1.0-ga imx_jb4.2.2_1.1.0-ga

Here "../android_jb4.2.2_1.1.0-ga_source/code/jb4.2.2_1.1.0-ga" is the location of the patches (i.e. directory created when you unzip release package)
"imx_jb4.2.2_1.1.0-ga" is the branch which will be created automatically for you to hold all patches (only in those existing Google gits).

If everything is OK, "c_patch" will generate the following output to indicate successful patch:
Success: Now you can build the Android code for FSL i.MX platform
The patch script ( requires some basic utilities like awk/sed. If they are not
available on your Linux computer, install them first.

Apply VAR-SOM-MX6 patches

After you setup your build machine,unpack Variscite's release Package:

$ cd ~/var_jb_422_110/jb_422_110_build
$ tar xvf ~/Downloads/var_jb422_110_r3.tar.bz2
$ variscite/install

Build Android Images

Build the Android Filesystem


If you would like to enable “Fastboot” edit bootable/bootloader/uboot-imx/include/configs/mx6q_var_som_nand_android.h and

  1. Uncomment the “#if 0” block starting at line 29.
  2. Modify the fbparts line change 448m@48m(android_root) to 448m@64m(android_root)
  • Change to Android top level directory.
$ cd ~/var_jb_422_110/jb_422_110_build
  • Execute the following commands
$ source build/

Select one of the below targets, based on your target platform:

$ lunch var_som_mx6q-user
$ lunch var_som_mx6dl-user
$ lunch var_som_mx6solo-user


$ make -j6

The above make will build the u-boot and Linux images for Variscite SOM's. You need to run it again.

$ make -j6

If you exit your system and want to re build your Android you need to run the above commands again.
"$ cd ~/var_jb_422_110/jb_422_110_build"
"$ source build/"
"$ lunch var_som_mx6q-user or $ lunch var_som_mx6dl-user or $ lunch var_som_mx6solo-user"

Generate UBI images

To generate UBI images to be installed on the NAND-flash, follow the below steps:

For Quad platform:

$ chmod 644 out/target/product/var_som_mx6q/system/build.prop
$ rm out/target/product/var_som_mx6q/userdata.img
$ make -j4 PRODUCT-var_som_mx6q-user BUILD_TARGET_FS=ubifs

For Dual Lite platform:

$ chmod 644 out/target/product/var_som_mx6dl/system/build.prop
$ rm out/target/product/var_som_mx6dl/userdata.img
$ make -j4 PRODUCT-var_som_mx6dl-user BUILD_TARGET_FS=ubifs

For Solo platform:

$ chmod 644 out/target/product/var_som_mx6solo/system/build.prop
$ rm out/target/product/var_som_mx6solo/userdata.img
$ make -j4 PRODUCT-var_som_mx6solo-user BUILD_TARGET_FS=ubifs
  • The above commands will build the Android file-system, kernel, related modules and U-Boot.
  • Android rootfs components (root and system directories) will be located in 'out/target/product/var_som_mx6'.
  • The UBI build must be run only after the first build.

Build boot.img

We use boot.img and booti as default commands to boot rather than the uramdisk and uImage.
You can use this command to generate boot.img under android environment:

$ source build/
$ lunch var_som_mx6q-user
$ make bootimage

Comment for build error:

If this is the first time you build on a 64bit machine you may encounter some error releated to lzo library and other. has detail information how to fix this.

Toolchain setup for manual build kernel and u-boot

Setup the toolchain path to point to arm-eabi- tools in prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin

$ export CROSS_COMPILE=~/var_jb_422_110/jb_422_110_build/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/arm-eabi-

Manual build Bootloader 

Change directory to u-boot

$ cd ~/var_jb_422_110/jb_422_110_build/bootable/bootloader/uboot-imx 

Execute following commands:

$ make ARCH=arm distclean
$ make ARCH=arm mx6q_var_som_android_config # VAR-SOM-MXQ/D, boot from MMC
$ make ARCH=arm mx6solo_var_som_android_config # VAR-SOM-MXSolo, boot from MMC
$ make ARCH=arm mx6dl_var_som_android_config # VAR-SOM-MXDL, boot from MMC
$ make ARCH=arm mx6q_var_som_nand_android_config # VAR-SOM-MXQ/D, boot from NAND
$ make ARCH=arm mx6solo_var_som_nand_android_config # VAR-SOM-MXSolo, boot from NAND
$ make ARCH=arm mx6dl_var_som_nand_android_config # VAR-SOM-MXDL, boot from NAND
$ make ARCH=arm 

This command will generate the u-boot Image 'u-boot.bin'

Manual build Android Linux Kernel and modules

Change directory to kernel

$ cd ~/var_jb_422_110/jb_422_110_build/kernel_imx 

Execute following commands

$ make ARCH=arm distclean
$ make ARCH=arm var_som_mx6_android_defconfig
$ make ARCH=arm uImage
$ make ARCH=arm modules

This will generate uImage(kernel image) in kernel/arch/arm/boot folder


The Android can either be booted from MMC/SD device or UBIFS on NAND. 

Boot From MMC/SD Card

This section will guide you through the process of installing and boot VAR-SOM-MX6 from SD/MMC device.

Create bootable SD card

Variscite provides a script that can be used to partition the SD card and to install the required images on it.

Please download from the FTP site.

If you buid an image for UBIFS you need to re run your build:

$ make clean
$ make -j6
$ make -j6

Connect the SD-Card(2GB>) to the Linux machine, using a memory card reader to the Linux machine.

  • Note the name allocated for this device. Type "dmesg". The SD card name should show up near the end, usually something like "SDC" (/dev/sdc) or "SDD" (/dev/sdd) or "MMC" . replace "/dev/mmcblk0" with the right one.
  • Run the following command:

To create SD card for VAR-SOM-MX6Q device:

$ cd ~/var_jb_422_110/jb_422_110_build
$ chmod a+x
$ sudo ./  /dev/mmcblk0 mx6q

To create SD card for VAR-SOM-MX6DL device:

$ cd ~/var_jb_422_110/jb_422_110_build
$ chmod a+x
$ sudo ./ /dev/mmcblk0 mx6dl

To create SD card for VAR-SOM-MX6Solo device:

$ cd ~/var_jb_422_110/jb_422_110_build
$ chmod a+x
$ sudo  ./ /dev/mmcblk0 mx6solo

Boot Android from SD card

  • Insert the SD card you just created into the MMC/SD slot on the custom board.
  • Press and hold the boot-select button and power-on the SOM.

Boot From NAND Flash

Flashing the U-Boot, boot image and Android UBI root file system into NAND can be done from target Linux shell.

The images  can be found at Android build machine under: "out/target/product/var_som_mx6".

Boot the target device using Variscite's pre-build NAND recovery SD image, then follow the instructions below:

Flashing U-Boot to NAND

We recommend using our nand-recovery utility to flash the Android. You can update the relevant files in /opt/recovery/Android and use it to flash your images.

# flash_eraseall /dev/mtd0 
# kobs-ng init <u-boot-mx6XXX.bin> --search_exponent=1 -v

Flashing the Boot Image to NAND

# flash_eraseall /dev/mtd3 
# nandwrite -p /dev/mtd3 <boot.img>

Flashing the Android UBI Root File-System to NAND

# flash_eraseall /dev/mtd5 2>/dev/null
# ubiformat /dev/mtd5 -f <android_root.img> -s 2048 -O 2048

Flashing Android with Fastboot

  1. Connect a USB OTG cable from the target board OTG port to a you host machine USB HOST port.
  2. Power up the board and hit return to stop the boot
  3. type fastboot in the u-boot prompt.

On the target:

$ sudo `which fastboot` flash boot out/target/product/var_som_mx6q/boot.img
$ sudo `which fastboot` flash recovery out/target/product/var_som_mx6q/recovery.img
$ sudo `which fastboot` flash android_root out/target/product/var_som_mx6q/android_root.img
$ sudo `which fastboot` reboot

Display Options

Selecting the display type is done by setting the bootcmd with the required display type.

The bootcmd is embedded into boot.img. To set the bootargs edit the file '~/imx-android-jb4.2.2_1.0.0-ga-var11/device/variscite/var_som_mx6/' as follows:

  • HDMI
BOARD_KERNEL_CMDLINE := console=ttymxc0,115200 init=/init video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24,bpp=32 video=mxcfb1:off video=mxcfb2:off arm_freq=1000 fbmem=48M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
  • Variscite's LCD (Capacitive and resistive)
BOARD_KERNEL_CMDLINE := console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,bpp=32 video=mxcfb1:off video=mxcfb2:off arm_freq=1000 fbmem=24M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale

Android ADB Setup

Android Debug Bridge (adb) is a versatile tool that let you manage the state of the Android-powered device.

For more information about how to setup ADB adb, see TI ADB Setup page at

NOTE: When using adb over USB on Windows Machine, edit android_winusb.inf to match VAR-SOM-MX6 vendor and product ids, under [Google.NTx86] section add:

%SingleAdbInterface%        = USB_Install, USB\VID_18D1&PID_0D02
%CompositeAdbInterface%     = USB_Install, USB\VID_18D1&PID_0D02&MI_00