VAR-SOM-MX7 Yocto Morty build

VAR-SOM-MX7 - Yocto Morty 2.2.1 based on FSL Community BSP 2.2 with L4.1.15_2.0.0-ga Linux release

Installing required packages

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

www.yoctoproject.org/docs/latest/yocto-project-qs/yocto-project-qs.html

Please make sure you host PC is running Ubuntu 16.04 64-bit and install the following packages:

sudo apt-get install gawk wget git-core diffstat unzip texinfo gcc-multilib build-essential chrpath socat libsdl1.2-dev
sudo apt-get install autoconf libtool libglib2.0-dev libarchive-dev
sudo apt-get install python-git xterm sed cvs subversion coreutils texi2html
sudo apt-get install docbook-utils python-pysqlite2 help2man make gcc g++ desktop-file-utils libgl1-mesa-dev
sudo apt-get install libglu1-mesa-dev mercurial automake groff curl lzop asciidoc u-boot-tools dos2unix mtd-utils
sudo apt-get install pv

Documentation

• Yocto Project Core - Morty 2.2.1 (released on 02/24/2017)

Documentation is available from www.yoctoproject.org

• FSL Community BSP Release Notes 2.2 documentation

Documentation is available from http://freescale.github.io

• Kernel documentation from fsl-yocto-L4.1.15_2.0.0-ga release

Documentation is available for download from fsl-yocto-imx-4.1.15_2.0.0-docs

Download Yocto Morty based on Freescale Community BSP

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

$ mkdir ~/bin (this step may not be needed if the bin folder already exists)
$ curl http://commondatastorage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
$ chmod a+x ~/bin/repo
$ export PATH=~/bin:$PATH

$ mkdir ~/var-fslc-yocto
$ cd ~/var-fslc-yocto
$ repo init -u https://github.com/varigit/variscite-bsp-platform.git -b morty
$ repo sync -j4

Setup and build Yocto

Supported images

The following images are provided by Variscite for evaluation purpose

• fsl-image-gui: Default Variscite demo image with a GUI without any QT content. This image recipe works on all backends for X11,DirectFB, Frame Buffer and Wayland and the content is limited to fit 512MB NAND.
• fsl-image-qt5: Extends fsl-image-gui image with QT5.7.1 support and various QT samples for X11, Frame Buffer and Wayland backends

The following images are provided by FSL Community BSP:

• fsl-image-machine-test: A console-only image that includes gstreamer packages, Freescale’s multimedia packages (VPU and GPU), and test and benchmark applications.
• fsl-image-mfgtool-initramfs: Small image to be used with Manufacturing Tool (mfg-tool) in a production environment.
• fsl-image-multimedia/fsl-image-multimedia-full: A console-only image that includes gstreamer packages and Freescale’s multimedia packages (VPU and GPU)

See the list of Yocto Project’s reference images in Yocto Project Reference Manual

Supported distros

The following distros can be used:

• fslc-x11: Distro for X11 without wayland. This distro include x11 feature and doesn’ has wayland support.
• fslc-framebuffer: Distro for Framebuffer graphical backend. This distro doesn’t include x11 and wayland features.
• fslc-wayland: Distro for Wayland without X11. This distro include wayland feature but doesn’t has x11 support.
• fslc-xwayland: Distro for Wayland with X11. This distro include both wayland and x11 features.

Note: Also standard Poky distros can be used

Build X11 GUI demo image

$ cd ~/var-fslc-yocto
$ MACHINE=imx7-var-som DISTRO=fslc-x11 . setup-environment build_x11

Optional steps: local.conf customization

launch bitbake:

Without Qt content:
$ bitbake fsl-image-gui

Or with Qt content:
$ bitbake fsl-image-qt5

NOTE: Some of the blitter-based I.MX GStreamer plugins do not work with X11 and Wayland backends. To get the most of the I.MX GPU/VPU acceleration use the fslc-framebuffer backend

Build console-only demo image with Freescale’s multimedia packages (VPU and GPU)

$ cd ~/var-fslc-yocto
$ MACHINE=imx7-var-som DISTRO=fslc-framebuffer . setup-environment build_fb

Optional steps: local.conf customization

Without Qt content:
$ bitbake fsl-image-gui

Or with Qt content:
$ bitbake fsl-image-qt5

local.conf customization

Change the downloads directory

Create a /opt/yocto_downloads directory and set its permissions:

$ sudo mkdir /opt/yocto_downloads
$ sudo chmod 777 /opt/yocto_downloads/

Direct downloads to it, by replacing 'DL_DIR ?= "${BSPDIR}/downloads/"' with 'DL_DIR = "/opt/yocto_downloads/"' in conf/local.conf:

$ sed -i 's/DL_DIR ?= "${BSPDIR}\/downloads/DL_DIR = "\/opt\/yocto_downloads/g' conf/local.conf

Add Eclipse debug and Qt creator support to your images

Append the following to the conf/local.conf file in your Yocto build directory, to add Eclipse debug and Qt creator support to your images:

EXTRA_IMAGE_FEATURES = " \
    debug-tweaks \
    tools-debug \
    eclipse-debug \
    "

IMAGE_INSTALL_append = " \
    tcf-agent \
    openssh-sftp-server \
    "

Use systemd instead of SysV init

Append the following to the conf/local.conf file in your Yocto build directory, to use systemd instead of SysV init in your images:

DISTRO_FEATURES_append = " systemd"
VIRTUAL-RUNTIME_init_manager = "systemd"
DISTRO_FEATURES_BACKFILL_CONSIDERED = "sysvinit"
VIRTUAL-RUNTIME_initscripts = ""
IMX_DEFAULT_DISTRO_FEATURES_append = " systemd"

Create a read-only root file system

Append the following to the conf/local.conf file in your Yocto build directory, to create a read-only rootfs:

EXTRA_IMAGE_FEATURES += "read-only-rootfs"

Build Results

The resulted images are located at tmp/deploy/images/imx7-var-som:

File Name	Description
fsl-image-gui-imx7-var-som.sdcard	This image is for SD card boot. It can be flashed as-is on an SD card that can then be used to boot your system. For detailed information refer to the Create a bootable SD card section below.
fsl-image-gui-imx7-var-som.tar.bz2	Tarball with rootfs files. Can be used to create an NFS root file system on the host. See the Setup TFTP/NFS Yocto system section for more info. Also used to create our extended SD card. See the Create a bootable SD card section below.
fsl-image-gui-imx7-var-som.ubi	A complete UBI image containing a UBIFS volume, for writing to NAND flash.
zImage	Linux kernel image, same binary for SD card/eMMC/NAND flash.
u-boot.imx-sd	U-Boot built for SD card/eMMC.
u-boot.imx-nand	U-Boot built for NAND flash.
zImage-imx7d-var-som-emmc.dtb	Device tree blob for SOMs with eMMC.
zImage-imx7d-var-som-nand.dtb	Device tree blob for SOMs with NAND flash.

Create a bootable SD card

SD card structure

The first unallocated 4MiB are saved for U-Boot. It can be replaced using the dd command as described in the Build U-Boot from source code section.
The first partition is formatted with FAT16 and contains the Linux image and device tree blobs. You can copy them as described in the Build the Linux kernel from source code section.
The second partition is formatted with ext4 and contains the file system (including the kernel modules).

Yocto pre-built bootable SD card

The Yocto build products contains many files as explained in Build Results section above including a ".sdcard" file. For example, fsl-image-gui-imx7-var-som.sdcard, depending on your build.
This is a complete image to be flashed directly to an SD card.
Example usage:

$ cd ~/var-imx-yocto-krogoth/build_x11
$ sudo umount /dev/sdX*
$ sudo dd if=tmp/deploy/images/imx7-var-som/fsl-image-gui-imx7-var-som.sdcard of=/dev/sdX bs=1M && sync
Replace sdX with the right device name.

Drawbacks of the native .sdcard yocto-built image:

• The second partition size doesn't use the entire SD card.
• The second partition is not labeled as rootfs.
• The NAND and eMMC flashing scripts are not included.

Create an extended SD card

Variscite provides the var-create-yocto-sdcard.sh script which creates our NAND/eMMC recovery SD card - an SD card based on the fsl-image-gui filesystem, which copies the NAND flash burning scripts and relevant binaries for your convenience.
Later, you will be able to follow either the more automatic VAR-SOM-MX7 Yocto Recovery SD card guide or the more manual Flashing the internal storage device guide to burn your images to NAND flash or eMMC.

Note:
This is essentially the same as our pre-built Recovery SD image, with the following main difference:
The pre-built image's rootfs partition size is 3700MiB, which is also the default size when using the script, but the script also has an option to set the rootfs partition size to fill the whole free space of the used SD card. Anyway, you can always resize the partition later with an external tool such as gparted.
Naturally, the pre-built image is more straight forward and easier to use, while the script method is easier to customize.

Usage:

• Follow the Setup and build Yocto guide, and bitbake fsl-image-gui.
• Plug-in the SD card to your Linux HOST PC, run dmesg and see which device is added (i.e. /dev/sdX or /dev/mmcblkX)

$ sudo MACHINE=imx7-var-som ~/var-imx-yocto-krogoth/sources/meta-variscite-imx/scripts/var_mk_yocto_sdcard/var-create-yocto-sdcard.sh <options> /dev/sdX
(Replace /dev/sdX with your actual device)

options:
  -h            Display help message
  -s            Only show partition sizes to be written, without actually write them
  -a            Automatically set the rootfs partition size to fill the SD card
  -r            Select alternative rootfs for recovery images (default: build_x11/tmp/deploy/images/imx7-var-som/fsl-image-gui-imx7-var-som.*)

If you don't use the '-a' option, a default rootfs size of 3700MiB will be used.
The '-r' option allows you to create a bootable SD card with an alternative image for the installation to NAND flash or eMMC.
Example: "-r tmp/deploy/images/imx7-var-som/fsl-image-qt5-imx7-var-som" -- selects the "Qt5 image with X11" recovery image

Boot board with a bootable SD card

Setting the BOOT SELECT DIP switches

Make sure the BOOT SELECT DIP switches on the carrier board are set correctly before you power on the board.

SW1-SW2
 0 - 0 : Boot from SD card
 1 - 0 : Boot from eMMC
 0 - 1 : Boot from NAND flash
 1 - 1 : Illegal

Note: The VAR-SOM-MX7 SOM comes with either NAND or eMMC, but not both.

Automatic Device Tree selection in U-Boot

As shown in the Build Results table above, we have different kernel device trees, corresponding to our different H/W configurations (sometimes they are renamed without the "zImage-" prefix).
We implemented a script in U-Boot's environment, which sets the fdt_file environment variable based on the detected hardware.

Enable/Disable Automatic Device Tree selection

To enable the automatic device tree selection in U-Boot (already enabled by default):

$ setenv fdt_file=undefined
$ saveenv

To disable the automatic device tree selection in U-Boot, set the device tree file manually:

$ setenv fdt_file=YOUR_DTB_FILE
$ saveenv

Flash images to NAND/eMMC

Please refer to VAR-SOM-MX7 NAND flash burning

QT5/Embedded runtime

Environment Variables

The QT5/Embedded require environment variables to run correctly. VAR-SOM-MX7 support QT Embedded over Linux Frame Buffer. For example /etc/profile.d/tslib.sh can be edited. The following example enable touch, mouse and keyboard:

export TSLIB_TSEVENTTYPE='INPUT'
export TSLIB_TSDEVICE='/dev/input/touchscreen0'
export TSLIB_CALIBFILE='/etc/pointercal'
export TSLIB_CONFFILE='/etc/ts.conf'
export TSLIB_CONSOLEDEVICE='none'
export TSLIB_FBDEVICE='/dev/fb0'
export TSLIB_PLUGINDIR='/usr/lib/ts'

export QT_QPA_PLATFORM=linuxfb:fb=/dev/fb0:size=800x480:mmSize=800x480
export QT_QPA_EVDEV_TOUCHSCREEN_PARAMETERS='/dev/input/touchscreen0'
export QT_QPA_GENERIC_PLUGINS='tslib:/dev/input/touchscreen0,evdevmouse:/dev/input/event5,evdevkeyboard:/dev/input/event3'

Running Application

$ cd /usr/share/qt5/examples/
$ touch/dials/dials --platform linuxfb
$ gui/rasterwindow/rasterwindow --platform linuxfb
$ touch/fingerpaint/fingerpaint  --platform linuxfb
$ widgets/mainwindows/mainwindow/mainwindow --platform linuxfb

UBIFS

The UBIFS image we create by default is for 512MiB NAND flash.
You can change the size by editing ~/var-imx-yocto-krogoth/sources/meta-variscite-imx/conf/machine/imx7-var-som.conf and comment/uncomment the relevant section.

Update Yocto Meta-Variscite

From time to time we will post updates to meta-variscite that will include new features and bug fixes.
Follow the instructions below to update your tree:

$ cd ~/var-imx-yocto-krogoth/sources/meta-variscite-imx/
$ git fetch origin
$ git checkout Krogoth-imx-4.1.15-var01
$ git pull

Setup your enviroment:
$ cd ~/var-imx-yocto-krogoth

For X11 image:
$ MACHINE=imx7-var-som DISTRO=fsl-imx-x11 source var-setup-release.sh -b build_x11

For FB image:
$ MACHINE=imx7-var-som DISTRO=fsl-imx-fb source var-setup-release.sh -b build_fb

In order to update the kernel and U-Boot:
$ bitbake -c cleanall u-boot-variscite linux-variscite cryptodev-module

For GUI image:
$ bitbake -c clean fsl-image-gui

For Qt5 image:
$ bitbake -c clean fsl-image-qt5

and build your image:

For GUI image:
$ bitbake fsl-image-gui

For Qt5 image:
$ bitbake fsl-image-qt5

Useful Bitbake commands

Bitbake Cheat Sheet

Useful bitbake commands

i.MX Yocto Project: ltib versus bitbake