Description

Leading embedded systems developer Rudolf Streif gives readers a solid grounding in the basics, then guides them through more advanced topics -- ranging from building board support packages to managing compliance. Students master the Yocto Project toolbox by working through the entire development lifecycle on a realistic project: a distributed home automation system consisting of multiple embedded devices with diverse functionality, all communicating via networking infrastructure.

Features

• Master the entire Yocto Project lifecycle: laying out system components, building the core OS stack, customization, configuration, application development, and deployment
• Maintain a common software base across multiple devices, while supporting different architectures and configurations
• Learn from a realistic, start-to-finish case study: a distributed home automation system containing multiple embedded and networked devices
• Perfect for engineers in many fast-growing Linux embedded systems markets: "hard" embedded, mobile, medical, IVI, aerospace, military, space systems, and beyond

Table of Contents

Foreword xv

Preface xvii

Acknowledgments xxi

About the Author xxiii

 

Chapter 1: Linux for Embedded Systems 1

1.1 Why Linux for Embedded Systems? 1

1.2 Embedded Linux Landscape 3

1.3 A Custom Linux Distribution–Why Is It Hard? 8

1.4 A Word about Open Source Licensing 9

1.5 Organizations, Relevant Bodies, and Standards 11

1.6 Summary 13

1.7 References 14

 

Chapter 2: The Yocto Project 15

2.1 Jumpstarting Your First Yocto Project Build 15

2.2 The Yocto Project Family 26

2.3 A Little Bit of History 28

2.4 Yocto Project Terms 31

2.5 Summary 33

2.6 References 34

 

Chapter 3: OpenEmbedded Build System 35

3.1 Building Open Source Software Packages 35

3.2 OpenEmbedded Workflow 39

3.3 OpenEmbedded Build System Architecture 45

3.4 Summary 56

3.5 References 57

 

Chapter 4: BitBake Build Engine 59

4.1 Obtaining and Installing BitBake 59

4.2 Running BitBake 61

4.3 BitBake Metadata 70

4.4 Metadata Syntax 71

4.5 Source Download 86

4.6 HelloWorld–BitBake Style 95

4.7 Dependency Handling 99

4.8 Version Selection 102

4.9 Variants 103

4.10 Default Metadata 103

4.11 Summary 107

4.12 References 108

 

Chapter 5: Troubleshooting 109

5.1 Logging 110

5.2 Task Execution 116

5.3 Analyzing Metadata 119

5.4 Development Shell 120

5.5 Dependency Graphs 121

5.6 Debugging Layers 122

5.7 Summary 124

 

Chapter 6: Linux System Architecture 127

6.1 Linux or GNU/Linux? 127

6.2 Anatomy of a Linux System 128

6.3 Bootloader 129

6.4 Kernel 134

6.5 User Space 141

6.6 Summary 143

6.7 References 144

 

Chapter 7: Building a Custom Linux Distribution 145

7.1 Core Images–Linux Distribution Blueprints 146

7.2 Building Images from Scratch 160

7.3 Image Options 161

7.4 Distribution Configuration 169

7.5 External Layers 181

7.6 Hob 181

7.7 Summary 184

 

Chapter 8: Software Package Recipes 185

8.1 Recipe Layout and Conventions 185

8.2 Writing a New Recipe 196

8.3 Recipe Examples 212

8.4 Devtool 218

8.5 Summary 224

8.6 References 224

 

Chapter 9: Kernel Recipes 225

9.1 Kernel Configuration 226

9.2 Kernel Patches 231

9.3 Kernel Recipes 233

9.4 Out-of-Tree Modules 251

9.5 Device Tree 257

9.6 Summary 258

9.7 References 259

 

Chapter 10: Board Support Packages 261

10.1 Yocto Project BSP Philosophy 261

10.2 Building with a BSP 265

10.3 Inside a Yocto Project BSP 277

10.4 Creating a Yocto Project BSP 282

10.5 Tuning 289

10.6 Creating Bootable Media Images 290

10.7 Summary 299

10.8 References 299

 

Chapter 11: Application Development 301

11.1 Inside a Yocto Project ADT 302

11.2 Setting Up a Yocto Project ADT 304

11.3 Building Applications 315

11.4 Eclipse Integration 317

11.5 Application Development Using an Emulated Target 331

11.6 Summary 333

11.7 References 334

 

Chapter 12: Licensing and Compliance 335

12.1 Managing Licenses 335

12.2 Managing Source Code 341

12.3 Summary 343

12.4 References 344

 

Chapter 13: Advanced Topics 345

13.1 Toaster 345

13.2 Build History 358

13.3 Source Mirrors 366

13.4 Autobuilder 368

13.5 Summary 374

13.6 References 375

 

Appendix A: Open Source Licenses 377

A.1 MIT License (MIT) 377

A.2 GNU General Public License (GPL) Version 2 378

A.3 GNU General Public License (GPL) Version 3 384

A.4 Apache License Version 2.0 397

 

Appendix B: Metadata Reference 403

 

Index 429 

Author

Rudolf J. Streif has more than twenty years of experience in software engineering as a developer and as a manager leading cross-functional engineering teams with more than one hundred members. He previously served as the Linux Foundation's Director of Embedded Solutions, coordinating the Foundation's efforts for Linux in embedded. Rudolf developed the Linux Foundation's training course on the Yocto Project, which he delivered multiple times to companies and in a crash course variant during Linux Foundation events. He lives in El Cajon, California.