Yocto Project my own quick start

This page is an excerpt from Yocto Project Quick Start Copyright © 2010-2020 Linux Foundation

The required packages

Packages and package installation vary depending on your development system. In general, you need to have root access and then install the required packages. The next few sections show you how to get set up with the right packages for Ubuntu.

If you have different distributions, please refer to the Yocto Project Documentation

You must install essential host packages on your build host. The following command installs the host packages based on an Ubuntu distribution:

$ sudo apt install gawk wget git diffstat unzip texinfo gcc build-essential chrpath \
socat cpio python3 python3-pip python3-pexpect xz-utils debianutils iputils-ping \
python3-git python3-jinja2 python3-subunit zstd liblz4-tool file locales libacl1

$ sudo locale-gen en_US.UTF-8

Development Code - branch 5.0 'scarthgap' LTS

Yocto Project code can be found in the Yocto Project Source Repositories. To check out current development code using git:

$ cd $HOME/yocto
$ git clone git://git.yoctoproject.org/poky -b scarthgap

poky/
├── bitbake
├── contrib
├── documentation
├── LICENSE
├── LICENSE.GPL-2.0-only
├── LICENSE.MIT
├── MAINTAINERS.md
├── MEMORIAM
├── meta
├── meta-poky
├── meta-selftest
├── meta-skeleton
├── meta-yocto-bsp
├── oe-init-build-env
├── README.hardware.md -> meta-yocto-bsp/README.hardware.md
├── README.md -> README.poky.md
├── README.OE-Core.md
├── README.poky.md -> meta-poky/README.poky.md
├── README.qemu.md
├── scripts
└── SECURITY.md

In addition you can install an optional but frequently essential metalayer

$ cd $HOME/yocto/poky
$ git clone git://git.openembedded.org/meta-openembedded -b scarthgap

Initializing the Build Environment

From the parent directory your Source Directory, initialize your environment and provide a meaningful Build Directory name:

$ cd $HOME/yocto/poky
$ source oe-init-build-env

At this point, the build directory has been created for you and it is now your current working directory. This is the default tree you should have to build.

poky/
├── bitbake
├── build          <----- run bitbake inside here
├── contrib
├── documentation
├── LICENSE
├── LICENSE.GPL-2.0-only
├── LICENSE.MIT
├── meta
├── meta-poky
├── meta-selftest
├── meta-skeleton
├── meta-yocto-bsp
├── oe-init-build-env
├── README.hardware -> meta-yocto-bsp/README.hardware
├── README.OE-Core
├── README.poky -> meta-poky/README.poky
├── README.qemu
└── scripts

Edit the configuration files

Edit $HOME/yocto/poky/build/conf/bblayers.conf

# POKY_BBLAYERS_CONF_VERSION is increased each time build/conf/bblayers.conf
# changes incompatibly
POKY_BBLAYERS_CONF_VERSION = "2"

BBPATH = "${TOPDIR}"
BBFILES ?= ""

BBLAYERS ?= " \
 /home/koan/yocto/poky/meta \
 /home/koan/yocto/poky/meta-poky \
 /home/koan/yocto/poky/meta-yocto-bsp \
 /home/koan/yocto/poky/meta-openembedded/meta-oe \
 "

Remember also to edit the file $HOME/yocto/poky/build/conf/local.conf and check the following variables:

MACHINE ?= "qemuarm"
DISTRO ?= "poky"
PACKAGE_CLASSES ?= "package_ipk"
INHERIT += "rm_work"

Building the Image

At this point, you need to select an image to build. If this is your first build using the Yocto Project, you should try the smallest and simplest image:

$ bitbake core-image-minimal  

Now you just wait for the build to finish.

Starting the QEMU Emulator

Before you start the QEMU emulator, be sure you have already to set up the emulation environment.

The following command setup the emulation environment and launch QEMU.

$ runqemu qemuarm

Or if you prefer, open a new shell terminal, setup the environment again and run

$ runqemu qemuarm nographic

Building cross-compiler

If you want you can create a re-distribuible cross-compiler targeted at your MACHINE.

$ bitbake meta-toolchain