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 (13 chapters)
Title Page
Packt Upsell

Reducing the Linux kernel image size

Before or in parallel with the root filesystem customization, embedded projects usually require an image size optimization that will reduce the boot time and memory usage.

Smaller images mean less storage space, less transmission time, and less programming time, which saves money both in manufacturing and field updates.

By default, the compressed Linux kernel image (zImage) for the Wandboard is around 6.2 MB. This recipe will show how we can reduce that.

How to do it...

An example of a minimal kernel configuration for a Wandboard that is able to boot from a microSD card root filesystem is the arch/arm/configs/wandboard-custom-minimal_defconfig file:

# CONFIG_SWAP is not set                                                         
CONFIG_HIGH_RES_TIMERS=y                                         ...