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

OTA updates

Updating over-the-air (OTA) means having the ability to push software to a device or group of devices via a network, usually without any end user interaction with the device. For this to happen, we need a central server to control the update process and a protocol for downloading the update to the update client. In a typical implementation, the client polls the update server from time to time to check if there are any updates pending. The polling interval needs to be long enough that the poll traffic does not take a significant portion of the network bandwidth, but short enough that the updates can be delivered in a timely fashion. An interval of tens of minutes to several hours is often a good compromise. The poll messages from the device contain some sort of unique identifier, such as a serial number or MAC address, and the current software version. From this, the update server can see if an update is needed. The poll messages may also contain other status information...