Comprehensive Real-World Guidance for Every Embedded Developer and Engineer
This book brings together indispensable knowledge for building efficient, high-value, Linux-based embedded products: information that has never been assembled in one place before. Drawing on years of experience as an embedded Linux consultant and field application engineer, Christopher Hallinan offers solutions for the specific technical issues you're most likely to face, demonstrates how to build an effective embedded Linux environment, and shows how to use it as productively as possible.
Hallinan begins by touring a typical Linux-based embedded system, introducing key concepts and components, and calling attention to differences between Linux and traditional embedded environments. Writing from the embedded developer's viewpoint, he thoroughly addresses issues ranging from kernel building and initialization to bootloaders, device drivers to file systems.
Hallinan thoroughly covers the increasingly popular BusyBox utilities; presents a step-by-step walkthrough of porting Linux to custom boards; and introduces real-time configuration via CONFIG_RT--one of today's most exciting developments in embedded Linux. You'll find especially detailed coverage of using development tools to analyze and debug embedded systems--including the art of kernel debugging.
• Compare leading embedded Linux processors
• Understand the details of the Linux kernel initialization process
• Learn about the special role of bootloaders in embedded Linux systems, with specific emphasis on U-Boot
• Use embedded Linux file systems, including JFFS2--with detailed guidelines for building Flash-resident file system images
• Understand the Memory Technology Devices subsystem for flash (and other) memory devices
• Master gdb, KGDB, and hardware JTAG debugging
• Learn many tips and techniques for debugging within the Linux kernel
• Maximize your productivity in cross-development environments
• Prepare your entire development environment, including TFTP, DHCP, and NFS target servers
• Configure, build, and initialize BusyBox to support your unique requirements
4.5. Chapter Summary
4.5. Chapter Summary
• The Linux kernel is more than 10 years old and has become a mainstream, well-supported operating system for many architectures.
• The Linux open source home is found at www.kernel.org. Virtually every release version of the kernel is available there, going all the way back to Linux 1.0.
• We leave it to other great books to describe the theory and operation of the Linux kernel. Here we discussed how it is built and identified the components that make up the image. Breaking up the kernel into understandable pieces is the key to learning how to navigate this large software project.
• This chapter covered the kernel build system and the process of modifying the build system to facilitate modifications.
• Several kernel configuration editors exist. We chose one and examined how it is driven and how to modify the menus and menu items within. These concepts apply to all the graphical front ends.
• The kernel itself comes with an entire directory structure full of useful kernel documentation. This is a helpful resource for understanding and navigating the kernel and its operation.
• This chapter concluded with a brief introduction to the options available for obtaining an embedded Linux distribution.