iMX6 Rex Android 4.4.2

Android version 4.4.2 is a mobile operating system (OS) based on the Linux kernel and currently developed by Google.

This document describes installation procedure for binary Freescale Android 4.4.2 image. Supported peripherals on iMX6 Rex Pro Module:

• HDMI / LVDS 640x480 LCD output
• Resistive touchscreen
• USB flash as external storage
• SD card as external storage
• Video playback
• Audio playback

Initial steps

Install Prerequisites

sudo apt-get install wget
sudo apt-get install e2fsprogs
sudo apt-get install util-linux

Create working directory

mkdir -pv ~/workdir/imx6/android/
cd ~/workdir/imx6/android/

Download installation files

git clone https://github.com/voipac/imx6_rex_bin_kk442
cd imx6_rex_bin_kk442/

SD card partition layout

This will be the final SD card partitioning layout at the end of installation procedure:

Partition type/index	Name	Start offset	Size	File system	Content
N/A	BOOT Loader	1 KB	1 MB	N/A	Not used
Primary 1	Boot	8 MB	8 MB	boot.img format, kernel + ramdisk	boot.img
Primary 2	Recovery	Follow Boot	8 MB	boot.img format, kernel + ramdisk	recovery.img
Logic 5 (Extended 3)	SYSTEM	Follow Recovery	512 MB	EXT4. Mount as /system	system.img
Logic 6 (Extended 3)	CACHE	Follow SYSTEM	512 MB	EXT4. Mount as /cache	Android cache for image store of OTA
Logic 7 (Extended 3)	Device	Follow CACHE	8 MB	EXT4. Mount as /vender	To Store MAC address files
Logic 8 (Extended 3)	Misc	Follow Device	4 MB	N/A	For recovery store bootloader message, reserve
Primary 4	DATA	Follow Misc	Total - Other images	EXT4. Mount at /data	Application data storage for the system application and for internal media partition in /mnt/sdcard/ dir

Install Bootloader

Download the image file

wget http://downloads.voipac.com/files/iMX6_Rex_Development_Kit/module/software/android/Android_kk442/binaries/u-boot-0x27800000_imx6q_20160410.bin

Flash the bootloader into SPI memory

mw.b 0x10800000 0xFF 0x80000
tftp 0x10800000 u-boot-0x27800000_imx6q_20160410.bin
sf probe 3:2
sf erase 0x0 0x80000
sf write 0x10800000 0x0 0x80000

Install Android

Extract system.img

7z x system.img.7z.001

Creating SD card

Note: Unmounted SD card during this process is essential otherwise the fsl-sdcard-partition script may fail to create a proper Android SD card.

For installation SD card partition script is used:

• This script requires boot.img, recovery.img and system.img files in the same directory as script itself
• /dev/mmcblk0 is the path to the SD card

Note: The script is working correctly only with /dev/mmcblk0 devices (USB to SD adaptors will not work).

chmod a+x fsl-sdcard-partition.sh 
sudo ./fsl-sdcard-partition.sh -f /dev/mmcblk0

Configure Bootloader

LVDS Display (LDB-ETV570)

Temporary boot settings

setenv machid 12a9
setenv bootargs console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,LDB-ETV570,if=RGB666 video=mxcfb1:off video=mxcfb2:off fbmem=10M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
booti mmc1

Persistent boot settings

setenv machid 12a9
setenv bootargs console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,LDB-ETV570,if=RGB666 video=mxcfb1:off video=mxcfb2:off fbmem=10M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
setenv bootcmd booti mmc1
saveenv
reset

Persistent boot settings (touch screen calibration)

setenv machid 12a9
setenv bootargs tsdev=tsc2007 console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,LDB-ETV570,if=RGB666 video=mxcfb1:off video=mxcfb2:off fbmem=10M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
setenv bootcmd booti mmc1
saveenv
reset

Triggering new touch screen calibration

rm /data/calibration 
reboot

HDMI Monitor

Temporary boot settings

setenv machid 12a9
setenv bootargs console=ttymxc0,115200 init=/init video=mxcfb0:dev=hdmi,1280x720M@60,if=RGB24,bpp=32 video=mxcfb1:off video=mxcfb2:off fbmem=28M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
booti mmc1

Persistent boot settings

setenv machid 12a9
setenv bootargs console=ttymxc0,115200 init=/init video=mxcfb0:dev=hdmi,1280x720M@60,if=RGB24,bpp=32 video=mxcfb1:off video=mxcfb2:off fbmem=28M vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
setenv bootcmd booti mmc1
saveenv
reset