Book Image

Mastering Embedded Linux Programming

By : Chris Simmonds
Book Image

Mastering Embedded Linux Programming

By: Chris Simmonds

Overview of this book

Mastering Embedded Linux Programming takes you through the product cycle and gives you an in-depth description of the components and options that are available at each stage. You will begin by learning about toolchains, bootloaders, the Linux kernel, and how to configure a root filesystem to create a basic working device. You will then learn how to use the two most commonly used build systems, Buildroot and Yocto, to speed up and simplify the development process. Building on this solid base, the next section considers how to make best use of raw NAND/NOR flash memory and managed flash eMMC chips, including mechanisms for increasing the lifetime of the devices and to perform reliable in-field updates. Next, you need to consider what techniques are best suited to writing applications for your device. We will then see how functions are split between processes and the usage of POSIX threads, which have a big impact on the responsiveness and performance of the final device The closing sections look at the techniques available to developers for profiling and tracing applications and kernel code using perf and ftrace.
Table of Contents (22 chapters)
Mastering Embedded Linux Programming
About the Author
About the Reviewers

The art of cross compiling

Having a working cross toolchain is the starting point of a journey, not the end of it. At some point, you will want to begin cross compiling the various tools, applications, and libraries that you need on your target. Many of them will be open source packages, each of which has its own method of compiling, and each with its own peculiarities. There are some common build systems, including:

  • Pure makefiles where the toolchain is controlled by the make variable CROSS_COMPILE

  • The GNU build system known as Autotools

  • CMake (

I will cover only the first two here since these are the ones needed for even a basic embedded Linux system. For CMake, there are some excellent resources on the CMake website referenced in the preceding point.

Simple makefiles

Some important packages are very simple to cross compile, including the Linux kernel, the U-Boot bootloader, and Busybox. For each of these, you only need to put the toolchain prefix in the make variable CROSS_COMPILE...