Book Image

Mastering Embedded Linux Programming - Third Edition

By : Frank Vasquez, Chris Simmonds
5 (3)
Book Image

Mastering Embedded Linux Programming - Third Edition

5 (3)
By: Frank Vasquez, Chris Simmonds

Overview of this book

If you’re looking for a book that will demystify embedded Linux, then you’ve come to the right place. Mastering Embedded Linux Programming is a fully comprehensive guide that can serve both as means to learn new things or as a handy reference. The first few chapters of this book will break down the fundamental elements that underpin all embedded Linux projects: the toolchain, the bootloader, the kernel, and the root filesystem. After that, you will learn how to create each of these elements from scratch and automate the process using Buildroot and the Yocto Project. As you progress, the book will show you how to implement an effective storage strategy for flash memory chips and install updates to a device remotely once it’s deployed. You’ll also learn about the key aspects of writing code for embedded Linux, such as how to access hardware from apps, the implications of writing multi-threaded code, and techniques to manage memory in an efficient way. The final chapters demonstrate how to debug your code, whether it resides in apps or in the Linux kernel itself. You’ll also cover the different tracers and profilers that are available for Linux so that you can quickly pinpoint any performance bottlenecks in your system. By the end of this Linux book, you’ll be able to create efficient and secure embedded devices using Linux.
Table of Contents (27 chapters)
1
Section 1: Elements of Embedded Linux
10
Section 2: System Architecture and Design Decisions
18
Section 3: Writing Embedded Applications
22
Section 4: Debugging and Optimizing Performance

Filesystems for NOR and NAND flash memory

To use raw flash chips for mass storage, you have to use a filesystem that understands the peculiarities of the underlying technology. There are three such filesystems:

  • JFFS2 (Journaling Flash File System 2): This was the first flash filesystem for Linux and is still in use today. It works for NOR and NAND memory, but is notoriously slow during mount.
  • YAFFS2 (Yet Another Flash File System 2): This is similar to JFFS2, but specifically for NAND flash memory. It was adopted by Google as the preferred raw flash filesystem on Android devices.
  • UBIFS (Unsorted Block Image File System): This works in conjunction with the UBI block driver to create a reliable flash filesystem. It works well with both NOR and NAND memory, and since it generally offers better performance than JFFS2 or YAFFS2, it should be the preferred solution for new designs.

All of these use MTD as the common interface to flash memory.

JFFS2

The Journaling...