From Variscite Wiki
VAR-SOM-MX6 - Yocto V4.1 Dora R2


This is the second release of VAR-SOM-MX6 - Yocto V4.1 Dora. We updated the kernel with features and cleanup update u-boot and added support for Bluetooth and camera on the Dual lite and Solo SOM versions.
We also added 2 packages that enable Eclipse/Yocto application debug. A debug application note will come soon.

Supported hardware and features

Board support

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

Software platform

Yocto Dora release.
Freescale release version 4.1
Meta freescale community release for Dora

Nand Recovery NAND-recovery SD V22 - 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
CAN bus
USB host
Host and Device
x3, up to 3.6 Mbps. Minicom avilable to use with the port
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

Variscite Yocto Dora release 2 for Freescale i.MX6 version 4.1.

Installing required packages

Follow the link below and install all the required packages on your machine.

For example, if your building machine is an Ubuntu machine:

sudo apt-get install gawk wget git-core diffstat unzip texinfo build-essential chrpath libsdl1.2-dev xterm

Variscite Yocto build is tested with Ubuntu 12.04 lts.

Get Yocto Dora for i.MX6 with Variscite VAR-SOM-MX6 support

Method 1

This method use a complete image of Yocto and Variscite BSP support. You will not have the git database using this method.

$ cd ~
$ tar xvf var_yocto_rel_v3.0.tar.bz2

This will install an entire source tree. No need to apply any patch.

Method 2 using "Repo"

This method use a "repo" to fetch Yocto and apply Variscite patch for BSP support. Install the `repo` utility:

$ mkdir ~/bin
$ curl > ~/bin/repo
$ chmod a+x ~/bin/repo
$ export PATH=~/bin:$PATH
we uploaded as a reference the repo we used.

Get Yocto Dora from github.

$ cd ~
$ mkdir var-som-mx6-dora-v3
$ cd var-som-mx6-dora-v3
$ repo init -u -b dora
$ repo sync

Download var_yocto_v3.2.tar.bz2 from Variscite's FTP.

$ tar xvf var_yocto_v3.0.tar.bz2
$ variscite/install
This method will keep the git repositories. It will enable you to track Variscite and your changes.

Setup and Customize your Yocto build

Setup the environment and build folder
choose based on your platform:

$ MACHINE=varsommx6q . setup-environment build_mx6q
$ MACHINE=varsommx6dual . setup-environment build_mx6dual
$ MACHINE=varsommx6solo  . setup-environment build_mx6solo
If you close your terminal and want to build Yocto you should change directory to ~var-som-mx6-dora-v3 and run the above command again. build_mx6q is your build directory and all bitbake commands should run from it

local.conf customizations

Edit you local.conf file:

$ gedit conf/local.conf 

Change your parallel build and download directory:

Parallel build

Set the build parameters to fully utilize your host machine BB_NUMBER_THREADS = '4'
PARALLEL_MAKE = '-j 6' BB_NUMBER_THREADS should be your host machine's number of threads minus 2 or same. PARALLEL_MAKE should be the number of threads your host machine has plus two.

Download directory.

Recommended to save download time and space. DL_DIR = "/home/<uname>/yocto_dl"

Build your image

$ bitbake fsl-image-gui 

Other image build options:

image name
A console-only image that fully supports the target device hardware.
Builds contents core-image-base plus Freescale test applications and multimedia components.
Builds contents of core-image-sato with Freescale test applications and multimedia with hardware accelerated X11

The resulted images are in tmp/deploy/images/varsommx6q.
Looking at tmp/deploy/images/varsommx6q you will find 6 main files that are linked to the actual file

Image Name
How to use
Not in Use

Flash into SD-card and use boot select to boot from.

$ sudo dd if=tmp/deploy/images/varsommx6q/fsl-image-gui-varsommx6q.sdcard of=/dev/devxxx bs=1024k

devxxx = mmcblk0 or sdX. Do dmesg after you insert an SD-Card into your build system to figure out the device name


Used to create an NFS root file system on the host.

$ sudo mkdir ../rootfs
$ sudo rm -rf ../rootfs/*
# sudo tar xvf tmp/deploy/images/varsommx6q/fsl-image-gui-varsommx6q.tar.bz2 -C ../rootfs

See apendix for setting an NFS server


The best practice is to use Variscite's NAND-recovery SD-Card. update the Yocto folder on the SD-Card
/opt/recover/Yocto and replace u-boot, uImage and the UBI files with the files on tmp/deploy/images.

You can also look at /sbin/ for the excat procedure to flash the nand.

U-Boot options

By default all images are built for NAND-based U-Boot. If you want to change the setting to build SD-Card images, change the board file.

under ~/var_yocto/sources/meta-fsl-arm-extra/conf/machine you will find Variscite board definitions.


Edit you specifc board and change UBOOT_MACHINE according to the folowing table.

Built for
VAR-SOM-MXQ/D,  boot from MMC
VAR-SOM-MXSolo, boot from MMC
VAR-SOM-MXDL,    boot from MMC
VAR-SOM-MXQ/D,  boot from NAND
VAR-SOM-MXSolo, boot from NAND
VAR-SOM-MXDL,    boot from NAND


Build the toolchain by:

$ bitbake meta-ide-support
$ bitbake meta-toolchain

The output will be located at tmp/deploy/sdk/. On a 64 bit Ubuntu you will get:

Install the tools by running:

$ tmp/deploy/sdk/

The toolchain name depend on your build machine and may change.

Build Linux out of Yocto tree

Prepare the Linux kernel

$ bitbake -c cleansstate linux-variscite
$ bitbake -c devshell linux-variscite 

This will open a new shell at ...tmp/work/varsommx6q-poky-linux-gnueabi/linux-variscite/3.0.35-r0/git#

Copy the Linux kernel to a new folder

$ mkdir ~/var-som-mx6-dora-v3/linux-imx
$ cp -a * ~/var-som-mx6-dora-v3/linux-imx
$ exit

change dir into the new Linux kernel folder

$ cd ~/var-som-mx6-dora-v3/linux-imx

Set the tools path:

$ export PATH=/opt/poky/1.5.1/sysroots/x86_64-pokysdk-linux/usr/bin:/opt/poky/1.5.1/sysroots/x86_64-pokysdk-linux/usr/bin/cortexa9hf-vfp-neon-poky-linux-gnueabi:$PATH

Clean the Linux kernel:

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- mrproper

Configure the Linux kernel:

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- var_som_mx6_defconfig

Change configuration if required:

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- menuconfig

Build the Linux kernel:

$ make -j6 ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- uImage
$ make -j6 ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- modules

The best practice of testing the new Linux kernel is using TFTP&NFS. Described in the apendix.

$ cp arch/arm/boot/uImage /tftpboot

Install the Linux modules into the rootfs file system

$ sudo make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- modules_install INSTALL_MOD_PATH=../rootfs

Build U-Boot out of Yocto tree

Prepare the U-Boot boot loader

$ bitbake -c cleansstate u-boot-variscite
$ bitbake -c devshell u-boot-variscite 

This will open a new shell at ...tmp/work/varsommx6q-poky-linux-gnueabi/linux-variscite/3.0.35-r0/git#

Copy the U-Boot boot loader to a new folder

$ mkdir ~/var-som-mx6-dora/uboot-imx
$ cp -a * ~/var-som-mx6-dora/uboot-imx
$ exit

change dir into the new u-boot folder

$ cd ~/var-som-mx6-dora/uboot-imx

set the tools path if required

$ export PATH=/opt/poky/1.5.1/sysroots/x86_64-pokysdk-linux/usr/bin:/opt/poky/1.5.1/sysroots/x86_64-pokysdk-linux/usr/bin/cortexa9hf-vfp-neon-poky-linux-gnueabi:$PATH

Clean the U-Boot

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- mrproper

Configure the U-Boot boot loader

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- mx6q_var_som_nand_config

Build the U-Boot boot loader

$ make -j6 ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- 

Use our NAND-recovery sd-card to burn your u-boot to the NAND-Flash.

In case you build an sd-card version use

sudo dd if=u-boot.bin of=/dev/mmcblk0 bs=512 seek=2 skip=2 conv=fsync

Set the /dev/mmcblk0 according to you host sd-card device.

Creating a recovery SD-Card

we use Ubuntu 12.04 mount convention and a laptop media name. "/media/var_som_mx6_rf" and "/dev/mmcblk0" are widely used in this section.
You should be aware of this and change the media name to you host machine name.

Create a new folder:

$ mkdir ~/my_recovery_sd
$ cd ~/my_recovery_sd

Insert Variscite recovery SD-Card version 19 into your host machine.

Copy the recovery folder from the SD-Card into your local folder:

$ sudo cp -a /media/var_som_mx6_rf/opt/recovery ./
$ sudo cp /media/var_som_mx6_rf/sbin/ ./

Update your local folder with the files you created during the Yocto build:

$ sudo cp ~/var-som-mx6-dora/build_mx6q/tmp/deploy/images/varsommx6q/fsl-image-gui-varsommx6q.ubi recovery/Yocto/rootfs.ubi.img
$ sudo cp ~/var-som-mx6-dora/build_mx6q/tmp/deploy/images/varsommx6q/fsl-image-gui-varsommx6q.tar.bz2 recovery/Yocto/rootfs.tar.bz2
$ sudo cp ~/var-som-mx6-dora/build_mx6q/tmp/deploy/images/varsommx6q/uImage recovery/Yocto/uImage
$ sudo cp ~/var-som-mx6-dora/build_mx6q/tmp/deploy/images/varsommx6q/u-boot.bin recovery/Yocto/u-boot.bin 

Copy the SD-Card image from your Yocto build folder to the local recovery folder:

$ sudo cp ~/var-som-mx6-dora/build_mx6q/tmp/deploy/images/varsommx6dual/fsl-image-gui-varsommx6dual.sdcard ./

Build U-Boot for SD-Card. Follow the "Build U-Boot out of Yocto tree" section.

Configure U-Boot with:

$ make ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- mx6q_var_som_config

Build U-Boot:

$ make -j6 ARCH=arm CROSS_COMPILE=arm-poky-linux-gnueabi- 

Copy U-Boot from your U-Boot build folder to the local recovery folder:

$ cp u-boot.bin ~/my_recovery_sd

From ~/my_recovery_sd folder

Unmount your SD-Card.

Build the SD-Card. First flash the SD-Card image and U-Boot.

$ sudo dd if=fsl-image-gui-varsommx6q.sdcard of=/dev/mmcblk0 bs=1M
$ sudo dd if=u-boot.bin of=/dev/mmcblk0 bs=512 seek=2 skip=2 conv=fsync
$ sync

Set the SD-Card label:

$ Sudo apt-get install gparted
$ sudo gparted
Set the label to var_som_mx6_rf

Mount the SD-Card. You can simply remove it and inster it again to your host machine.

Copy all files from the recovery folder on your host machibe into the SD-Card:

$ sudo cp -a recovery/ /media/var_som_mx6_rf/opt/
$ sudo cp /media/var_som_mx6_rf/sbin/
$ sudo rm /media/var_som_mx6_rf/var/lib/alsa/asound.state 

If you want you can back up your new SD-Card image:

Un mount the SD-Card

$ sudo dd of=mx6qd-som-nand-recovery-sd.v19.img if=/dev/mmcblk0 bs=1M 

I used "/dev/mmcblk0" as the SD-Card device name. You should replace it with your own SD-Card device name.

Useful Bitbake commands

Bitbake Cheat Sheet

Useful bitbake commands

i.MX Yocto Project: ltib versus bitbake