Short introduction to Yocto

The RITY SDK is using Yocto as foundation. This section will provide some basic knowledge to get started with Yocto.

Building instructions

This section will explain the building instruction from the Building the RITY SDK section. This section is assuming that the SDK source code has already been downloaded.

cd rity
export TEMPLATECONF=${PWD}/src/meta-rity/meta/conf/
source src/poky/oe-init-build-env
DISTRO=rity-demo bitbake rity-demo-image

Loading the Yocto build environment

In order to be able to use the Yocto tools, you must first load the yocto environment settings. To do this you need to run the following command:

export TEMPLATECONF=${PWD}/src/meta-rity/meta/conf/
source src/poky/oe-init-build-env

Setting TEMPLATECONF is only needed the first time you will run the source command. Sourcing the oe-init-build-env script will add the Yocto tools in your PATH variable.

The first time you source the oe-init-build-env script, it will create the following files.

rity
└── build
    └── conf
        ├── bblayers.conf
        ├── local.conf
        └── templateconf.cfg

The file templateconf.cfg contains the value of the TEMPLATECONF variable. The bblayers.conf and local.conf files are copied over from the sample files present in the path pointed to by the TEMPLATECONF variable.

Building an image

The command to build an image is:

DISTRO=rity-demo bitbake MACHINE=<machine> rity-demo-image

bitbake is the tool used to build images and packages. Setting the DISTRO and MACHINE variables on the command line allows to override their values set in local.conf.

The image will be stored in build/tmp/deploy/images/<machine>.

Configuration files

local.conf

local.conf contains your local build configuration.

Instead of setting the DISTRO and MACHINE variable on the bitbake command line, you can also set them in local.conf.

Please refer to the official Yocto Documentation to read more about local.conf.

bblayers.conf

The bblayers.conf file is mostly used to specify the path to all the Yocto meta layer that bitbake will parse.

Please refer to the official Yocto Documentation to read more about bblayers.conf.