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About the hardware

Connector Interfaces

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Use the following as a reference for the connector interfaces on the phyBOARD-i.MX7 that will be used in this Quickstart.

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DevelopmentHostSetup DevelopmentHostSetup

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Building Images from Source

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This section explains how to build your BSP from sourcessource.

Development Host Setup

Host Debian Packages

Yocto development requires certain packages to be installed. Run the following commands to ensure you have the packages installed:

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

Verify that the preferred shell for your Host PC is ''bash'' and not ''dash'':

sudo dpkg-reconfigure dash 
# Respond "No" to the prompt asking "Install dash as /bin/sh?"

Repo Tool

Download and install the repo tool. This tool is used to obtain Yocto source from Git.

cd /opt
sudo mkdir bin

# /opt/ directory has root permission, change the permissions so your user account can access this folder. In the following replace <user> with your specific username
sudo chown -R <user>: bin

cd bin
curl http://commondatastorage.googleapis.com/git-repo-downloads/repo > ./repo
chmod a+x repo

Add the repo directory in your PATH, using export from the command line or permanently by including it in .bashrc:

export PATH=/opt/bin/:$PATH

Git Setup

If you have not yet configured your Git environment on this machine, please execute the following commands to set your user name and email address. See here for more information on getting started with Git.

git config --global user.email "your@email.com" 
git config --global user.name "Your Name"

Server Setup (Optional)

Building With Bitbake

Yocto Build Steps

BSP Directory Setup

Create a directory which will house your BSP development. In this example the BSP directory is /opt/PHYTEC_BSPs/. This is not a requirement and if another location is preferred (ex. ~/PHYTEC_BSPs) feel free to modify. We recommend using /opt over your HOME directory to avoid errors attributed to ~ syntax as well as the sudo requirement for the root filesystem and automation package building. We also recommend creating a package download directory (yocto_dl) separate from the yocto tree (yocto_imx7), as it makes resetting the build environment easier and subsequent build times much faster.

sudo mkdir /opt/PHYTEC_BSPs
cd /opt/

# /opt/ directory has root permission, change the permissions so your user account can access this folder. In the following replace <user> with your specific username
sudo chown -R <user>: PHYTEC_BSPs

cd PHYTEC_BSPs
mkdir yocto_imx7
mkdir yocto_dl
cd yocto_imx7
export YOCTO_DIR=`pwd`

At this point you will now be able to navigate to the Yocto directory using the $YOCTO_DIR environment variable.

Download the BSP Meta Layers

Download the manifest file for BSP-Yocto-FSL-iMX7-PD17.2.x:

cd $YOCTO_DIR 
repo init -u https://stash.phytec.com/scm/pub/manifests-phytec.git -b imx7 -m BSP-Yocto-FSL-iMX7-PD17.2.0.xml

Download the Yocto meta layers specified in the manifest file:

repo sync

Start the Build

Run the Yocto build directory setup. The TEMPLATECONF variable is used to set the source of the local configuration files (conf/bblayers.conf and conf/local.conf), which are located in the meta-phytec layer:

cd $YOCTO_DIR
TEMPLATECONF=$YOCTO_DIR/sources/meta-phytec/meta-phytec-fsl/conf MACHINE=<Yocto Machine> source sources/poky/oe-init-build-env build

Add the the new download directory to build/conf/local.conf:

DL_DIR ?= "/opt/PHYTEC_BSPs/yocto_dl"

Maximize build efficiency by modifying the BB_NUMBER_THREADS variable to suit your host development system. This sets the maximum number of tasks that BitBake should run in parallel. Also set the variable PARALLEL_MAKE to specify the number of threads that make can run. By default, these are set to 4 in build/conf/local.conf:

# Parallelism options - based on cpu count 
BB_NUMBER_THREADS ?= "4" 
PARALLEL_MAKE ?= "-j 4"

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ACCEPT_FSL_EULA = "1"

The setup is complete and you now have everything to complete a build. This BSP has been tested with the fsl-image-gui image. It is suggested that you start with this image to verify functionality before building other images. Alternate images are located in various meta layers at meta*/recipes*/images/*.bb. They can be found using the command bitbake-layers show-recipes "*-image*" in $YOCTO_DIR/build/.

The following will start a build from scratch including installation of the toolchain as well as the bootloader, Linux kernel, and root filesystem images.

cd $YOCTO_DIR/build
MACHINE=<Yocto Machine> bitbake fsl-image-gui

Built Images

All images generated by bitbake are deployed to $YOCTO_DIR/build/tmp/deploy/images/<Yocto Machine>:

• SD Image: fsl-image-gui-<Yocto Machine>.sdcard
• Bootloader: u-boot.imx
• Kernel: zImage
• Kernel device tree file: zImage-<Yocto Machine>.dtb
  • device tree used when FreeRTOS is running on M4: zImage-<Yocto Machine>-m4.dtb
• Root Filesystem: fsl-image-gui-<Yocto Machine>.ext4

Source Locations:

• Kernel:  $YOCTO_DIR/build/tmp/work/<Yocto Machine>-poky-linux-gnueabi/linux-phytec-fsl/4.1.15+git_v4.1.15-phy1-r0/git/  
  • The device tree file to modify within the linux kernel source is: arch/arm/boot/dts/<Yocto Machine>.dts and its dependencies

• U-Boot:$YOCTO_DIR/build/tmp/work//<Yocto Machine>-poky-linux-gnueabi/u-boot-phytec/2016.03+git_v2016.03-phy1-r0/git/ 

  • Board file is located at: board/phytec/mx7d_phyboard_zeta/mx7d_phyboard_zeta.c

• Toolchain: $YOCTO_DIR/build/tmp/sysroots/x86_64-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-

Build Time Optimizations

The build time will vary depending on the package selection and Host performance. Beyond the initial build, after making modifications to the BSP, a full build is not required. Use the following as a reference to take advantage of optimized build options and reduce the build time.

To rebuild Barebox:

bitbake u-boot-phytec -f -c compile && bitbake u-boot-phytec

To rebuild the Linux kernel:

bitbake linux-phytec-fsl -f -c compile && bitbake linux-phytec-fsl

The Yocto project's Bitbake User Manual provides useful information regarding build options: http://www.yoctoproject.org/docs/2.1.1/bitbake-user-manual/bitbake-user-manual.html

BSP Documentation

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