Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By : Alex Gonzalez
Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By: Alex Gonzalez

Overview of this book

The Yocto Project has become the de facto distribution build framework for reliable and robust embedded systems with a reduced time to market.You'll get started by working on a build system where you set up Yocto, create a build directory, and learn how to debug it. Then, you'll explore everything about the BSP layer, from creating a custom layer to debugging device tree issues. In addition to this, you’ll learn how to add a new software layer, packages, data, scripts, and configuration files to your system. You will then cover topics based on application development, such as using the Software Development Kit and how to use the Yocto project in various development environments. Toward the end, you will learn how to debug, trace, and profile a running system. This second edition has been updated to include new content based on the latest Yocto release.
Table of Contents (7 chapters)

Configuring the Linux kernel


The Linux kernel contains a set of default machine configurations. For ARM, these are under the arch/arm/configs directory on the Linux source. The Yocto Project, however, uses a copy of this configuration file inside the BSP layer metadata. This enables the use of different configuration files for different purposes.

In this recipe, we will see how to configure the Linux kernel and add the resulting configuration file to our BSP layer.

Getting ready

Before configuring the kernel, we need to provide a default configuration for our machine, which is the one the Yocto project uses to configure a kernel. When defining a new machine in your BSP layer, you need to provide a defconfig file.

The Wandboard's defconfig file is stored under sources/meta-freescale-3rdparty/recipes-kernel/linux/linux-wandboard/defconfig.

This will be the base defconfig file for our custom hardware, so we copy it to our BSP layer:

$ cd /opt/yocto/fsl-community-bsp/sources$ mkdir -p meta-bsp-custom...