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
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Chapter 7. Creating a Storage Strategy

The mass storage options for embedded devices have a great impact on the rest of the system in terms of robustness, speed, and methods of in-field updates.

Most devices employ flash memory in some form or other. Flash memory has become much less expensive over the past few years as storage capacities have increased from tens of megabytes to tens of gigabytes.

In this chapter, I will begin with a detailed look at the technology behind flash memory and how different memory organization affects the low level driver software that has to manage it, including the Linux memory technology device layer, MTD.

For each flash technology, there are different choices of filesystem. I will describe those most commonly found on embedded devices and complete the survey with a section giving a summary of choices for each type of flash.

The last sections consider techniques to make the best use of flash memory, look at how to update devices in the field, and draw everything...