How to Install Yocto Project

21-08-2024 661 words 4 minutes

Contents

Yocto Project

Yocto Project is an open-source collaboration project that helps developers create custom Linux-based systems. This guide will walk you through setting up Yocto with STM32MP1 support.

Basic Dependencies

First, update your system and install the essential dependencies:

sudo apt update
sudo apt upgrade
sudo apt install -y build-essential bc chrpath cpio diffstat gawk git texinfo wget python3 python3-pip
sudo locale-gen en_US.UTF-8

Additional Dependencies

You will also need some additional dependencies for Yocto:

sudo apt install -y libssl-dev
sudo apt install -y rpcbind
sudo systemctl start rpcbind
sudo systemctl enable rpcbind

Clone Poky

Clone the Yocto Poky build system:

mkdir -p ~/Projects/yocto
cd ~/Projects/yocto
git clone -b kirkstone https://github.com/yoctoproject/poky.git 
cd poky

Image showing the process of cloning Poky — Cloning Poky

Clone STM32MP Layers

For STM32MP support, clone the meta layer:

cd ~/Projects/yocto
git clone -b kirkstone https://github.com/STMicroelectronics/meta-st-stm32mp.git

Image showing the process of cloning STM32MP layers — Cloning STM32MP Layers

Clone meta-openembedded

You’ll also need the meta-openembedded layer for additional package support:

cd ~/Projects/yocto
git clone -b kirkstone https://github.com/openembedded/meta-openembedded.git

Image showing the process of cloning meta-openembedded — Cloning meta-openembedded

Note: I am using the kirkstone branch (Yocto Project 4.0) for this setup. Branches are also known by their code names or series versions. For more details on available branches and their status, check the Yocto Project releases page

Note: Using git clone -b kirkstone [URL] directly checks out the kirkstone branch during cloning, making the process faster by avoiding the download of unnecessary data. If you’ve already cloned the repository, you can switch to the kirkstone branch afterward with git checkout kirkstone.

Configure the Build Environment

Initialize the build environment:

cd ~/Projects/yocto
source poky/oe-init-build-env build-mp1
cd build-mp1

Image showing the process of initializing the build environment for STM32MP1 — Initializing the Build Environment for STM32MP1

Configure BBLayers and Local Conf

Edit the bblayers.conf file to include necessary layers:

nano conf/bblayers.conf

Add the following layers:


BBLAYERS ?= " \
  /home/user/Projects/yocto/poky/meta \
  /home/user/Projects/yocto/poky/meta-poky \
  /home/user/Projects/yocto/poky/meta-yocto-bsp \
  /home/user/Projects/yocto/meta-openembedded/meta-oe \
  /home/user/Projects/yocto/meta-openembedded/meta-python \
  /home/user/Projects/yocto/meta-st-stm32mp \
"

Save and close the file (in nano, press Ctrl+O, then Enter, then Ctrl+X).

Image showing the bblayers.conf configuration — Editing bblayers.conf

Modify the local.conf file to target the STM32MP1 machine:

nano conf/local.conf

Set the machine:

#MACHINE ??= “qemux86-64”
MACHINE = "stm32mp1"

Image showing the process of setting the STM32MP1 machine in local.conf — Setting the STM32MP1 Machine

If your system has less than 8GB of RAM, add the following to limit memory usage:

XZ_DEFAULTS = "--memlimit=1500MiB"

Alias Python Command

Yocto Project tools rely on the python command, so you might need to alias python to python3.

Follow these steps: Edit .bashrc File Open your .bashrc file with nano:

nano ~/.bashrc

Add Alias

Scroll to the bottom of the file and add the following line:

alias python=python3

Save and exit by pressing Ctrl+O, Enter, and then Ctrl+X.

Update Shell

Apply the changes to your current shell session:

source ~/.bashrc

Verify Python Version

Ensure python points to python3:

python --version

It should display something like Python 3.12.3

Install Python Packages

Before continuing, you will need to install Python packages manually:

Download the packages:

👉 pyasyncore-1.0.4.tar.gz

👉 pyinotify-0.9.6.tar.gz

Install the packages:

tar -zxvf pyasyncore-1.0.4.tar.gz
cd pyasyncore-1.0.4
sudo python3 setup.py install

tar -zxvf pyinotify-0.9.6.tar.gz
cd pyinotify-0.9.6
sudo python3 setup.py install

Run Bitbake

You can now configure and build your project using bitbake:

Check the layers:

bitbake-layers show-layers

Image showing the layers configuration using bitbake — Checking Layers

To configure the kernel:

bitbake -c menuconfig virtual/kernel

Image showing Bitbake running processes in terminal — Running Processes for Bitbake

Image showing the Bitbake menuconfig command — the Bitbake Command

Troubleshooting Bitbake Reconnection Issues

If you encounter the error:

NOTE: Reconnecting to bitbake server…

NOTE: Previous bitbake instance shutting down?, waiting to retry… First, check if any Bitbake processes are still running by running:

ps aux | grep bitbake

If you find processes like this:

ombhatt    44968  0.6  2.5 411496 206820 ?       S    18:01   0:42 python3 /home/ombhatt/Projects/yocto/poky/bitbake/bin/bitbake -c menuconfig virtual/kernel
ombhatt    44969  0.0  0.5 105948 40592 ?        S    18:01   0:00 python3 /home/ombhatt/Projects/yocto/poky/bitbake/bin/bitbake -c menuconfig virtual/kernel

Terminate them using:

kill -9 44968
kill -9 44969

After terminating any running Bitbake processes, try running that bitbake command again

To build a minimal image:

bitbake core-image-minimal

Clean Up

If you need to clean the build:

bitbake -c cleanall core-image-minimal
rm -rf tmp

List Images

To view the available images:

ls tmp/deploy/images/stm32mp1

For more detailed steps, refer to Yocto’s official documentation & Bootlin Yocto Slides 👉 PDF .