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| Foreword | |
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| Preface | |
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| Acknowledgments | |
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| About the Author | |
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| Introduction | |
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| Why Linux? | |
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| Embedded Linux Today | |
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| Open Source and the GPL | |
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| Free Versus Freedom | |
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| Standards and Relevant Bodies | |
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| Linux Standard Base | |
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| Open Source Development Labs | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Your First Embedded Experience | |
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| Embedded or Not? | |
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| BIOS Versus Bootloader | |
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| Anatomy of an Embedded System | |
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| Typical Embedded Linux Setup | |
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| Starting the Target Board | |
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| Booting the Kernel | |
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| Kernel Initialization: Overview | |
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| First User Space Process: init | |
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| Storage Considerations | |
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| Flash Memory | |
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| NAND Flash | |
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| Flash Usage | |
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| Flash File Systems | |
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| Memory Space | |
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| Execution Contexts | |
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| Process Virtual Memory | |
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| Cross-Development Environment | |
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| Embedded Linux Distributions | |
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| Commercial Linux Distributions | |
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| Do-It-Yourself Linux Distributions | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Processor Basics | |
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| Stand-alone Processors | |
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| IBM 970FX | |
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| Intel Pentium M | |
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| Freescale MPC7448 | |
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| Companion Chipsets | |
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| Integrated Processors: Systems on Chip | |
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| PowerPC | |
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| AMCC PowerPC | |
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| Freescale PowerPC | |
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| MIPS | |
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| Broadcom MIPS | |
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| AMD MIPS | |
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| Other MIPS | |
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| ARM | |
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| TI ARM | |
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| Freescale ARM | |
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| Intel ARM XScale | |
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| Other ARM | |
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| Other Architectures | |
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| Hardware Platforms | |
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| CompactPCI | |
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| ATCA | |
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| Chapter Summary | |
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| Suggestions For Additional Reading | |
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| The Linux Kernel-A Different Perspective | |
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| Background | |
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| Kernel Versions | |
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| Kernel Source Repositories | |
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| Linux Kernel Construction | |
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| Top-Level Source Directory | |
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| Compiling the Kernel | |
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| The Kernel Proper: vmlinux | |
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| Kernel Image Components | |
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| Subdirectory Layout | |
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| Kernel Build System | |
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| The Dot-Config | |
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| Configuration Editor(s) | |
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| Makefile Targets | |
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| Kernel Configuration | |
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| Custom Configuration Options | |
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| Kernel Makefiles | |
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| Kernel Documentation | |
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| Obtaining a Linux Kernel | |
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| What Else Do I Need? | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Kernel Initialization | |
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| Composite Kernel Image: Piggy and Friends | |
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| The Image Object | |
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| Architecture Objects | |
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| Bootstrap Loader | |
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| Boot Messages | |
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| Initialization Flow of Control | |
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| Kernel Entry Point: head.o | |
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| Kernel Startup: main.c | |
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| Architecture Setup | |
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| Kernel Command Line Processing | |
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| The_setup Macro | |
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| Subsystem Initialization | |
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| The*_initcall Macros | |
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| The init Thread | |
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| Initialization via initcalls | |
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| Final Boot Steps | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| System Initialization | |
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| Root File System | |
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| FHS: File System Hierarchy Standard | |
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| File System Layout | |
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| Minimal File System | |
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| The Root FS Challenge | |
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| Trial-and-Error Method | |
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| Automated File System Build Tools | |
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| Kernel's Last Boot Steps | |
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| First User Space Program | |
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| Resolving Dependencies | |
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| Customized Initial Process | |
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| The Init Process | |
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| inittab | |
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| Example Web Server Startup Script | |
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| Initial RAM Disk | |
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| Initial RAM Disk Purpose | |
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| Booting with initrd | |
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| Bootloader Support for initrd | |
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| initrd Magic: linuxrc | |
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| The initrd Plumbing | |
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| Building an initrd Image | |
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| Using initramfs | |
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| Shutdown | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Bootloaders | |
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| Role of a Bootloader | |
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| Bootloader Challenges | |
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| DRAM Controller | |
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| Flash Versus RAM | |
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| Image Complexity | |
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| Execution Context | |
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| A Universal Bootloader: Das U-Boot | |
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| System Configuration: U-Boot | |
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| U-Boot Command Sets | |
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| Network Operations | |
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| Storage Subsystems | |
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| Booting from Disk: U-Boot | |
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| Porting U-Boot | |
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| EP405 U-Boot Port | |
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| U-Boot Makefile Configuration Target | |
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| EP405 Processor Initialization | |
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| Board-Specific Initialization | |
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| Porting Summary | |
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| U-Boot Image Format | |
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| Other Bootloaders | |
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| Lilo | |
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| GRUB | |
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| Still More Bootloaders | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Device Driver Basics | |
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| Device Driver Concepts | |
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| Loadable Modules | |
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| Device Driver Architecture | |
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| Minimal Device Driver Example | |
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| Module Build Infrastructure | |
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| Installing Your Device Driver | |
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| Loading Your Module | |
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| Module Utilities | |
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| insmod | |
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| Module Parameters | |
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| lsmod | |
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| modprobe | |
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| depmod | |
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| rmmod | |
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| modinfo | |
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| Driver Methods | |
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| Driver File System Operations | |
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| Device Nodes and mknod | |
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| Bringing It All Together | |
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| Device Drivers and the GPL | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| File Systems | |
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| Linux File System Concepts | |
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| Partitions | |
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| ext2 | |
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| Mounting a File System | |
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| Checking File System Integrity | |
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| ext3 | |
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| ReiserFS | |
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| JFFS2 | |
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| cramfs | |
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| Network File System | |
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| Root File System on NFS | |
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| Pseudo File Systems | |
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| Proc File System | |
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| sysfs | |
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| Other File Systems | |
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| Building a Simple File System | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| MTD Subsystem | |
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| Enabling MTD Services | |
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| Building MTD | |
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| MTD Basics | |
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| Configuring MTD | |
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| MTD Partitions | |
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| Redboot Partition Table Partitioning | |
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| Kernel Command Line Partitioning | |
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| Mapping Driver | |
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| Flash Chip Drivers | |
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| Board-Specific Initialization | |
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| MTD Utilities | |
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| JFFS2 Root File System | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| BusyBox | |
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| Introduction to BusyBox | |
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| BusyBox is Easy | |
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| BusyBox Configuration | |
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| Cross-Compiling BusyBox | |
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| BusyBox Operation | |
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| BusyBox Init | |
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| Example rcS Initialization Script | |
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| BusyBox Target Installation | |
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| BusyBox Commands | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Embedded Development Environment | |
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| Cross-Development Environment | |
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| "Hello World"-Embedded | |
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| Host System Requirements | |
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| Hardware Debug Probe | |
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| Hosting Target Boards | |
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| TFTP Server | |
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| BOOTP/DHCP Server | |
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| NFS Server | |
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| Target NFS Root Mount | |
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| U-Boot NFS Root Mount Example | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Development Tools | |
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| GNU Debugger (GDB) | |
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| Debugging a Core Dump | |
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| Invoking GDB | |
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| Debug Session in GDB | |
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| Data Display Debugger | |
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| cbrowser/cscope | |
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| Tracing and Profiling Tools | |
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| strace | |
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| strace Variations | |
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| ltrace | |
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| ps | |
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| top | |
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| mtrace | |
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| dmalloc | |
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| Kernel Oops | |
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| Binary Utilities | |
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| readelf | |
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| Examining Debug Info Using readelf | |
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| objdump | |
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| objcopy | |
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| Miscellaneous Binary Utilities | |
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| strip | |
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| addr2line | |
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| strings | |
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| ldd | |
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| nm | |
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| prelink | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Kernel Debugging Techniques | |
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| Challenges to Kernel Debugging | |
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| Using KGDB for Kernel Debugging | |
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| KGDB Kernel Configuration | |
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| Target Boot with KGDB Support | |
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| Useful Kernel Breakpoints | |
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| Debugging the Linux Kernel | |
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| gdb Remote Serial Protocol | |
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| Debugging Optimized Kernel Code | |
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| gdb User-Defined Commands | |
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| Useful Kernel gdb Macros | |
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| Debugging Loadable Modules | |
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| printk Debugging | |
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| Magic SysReq Key | |
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| Hardware-Assisted Debugging | |
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| Programming Flash Using a JTAG Probe | |
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| Debugging with a JTAG Probe | |
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| When It Doesn't Boot | |
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| Early Serial Debug Output | |
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| Dumping the printk Log Buffer | |
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| KGDB on Panic | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Debugging Embedded Linux Applications | |
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| Target Debugging | |
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| Remote (Cross) Debugging | |
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| gdbserver | |
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| Debugging with Shared Libraries | |
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| Shared Library Events in GDB | |
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| Debugging Multiple Tasks | |
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| Debugging Multiple Processes | |
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| Debugging Multithreaded Applications | |
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| Debugging Bootloader/Flash Code | |
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| Additional Remote Debug Options | |
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| Debugging via Serial Port | |
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| Attaching to a Running Process | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Porting Linux | |
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| Linux Source Organization | |
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| The Architecture Branch | |
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| Custom Linux for Your Board | |
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| Prerequisites and Assumptions | |
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| Customizing Kernel Initialization | |
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| Static Kernel Command Line | |
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| Platform Initialization | |
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| Early Variable Access | |
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| Board Information Structure | |
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| Machine-Dependent Calls | |
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| Putting It All Together | |
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| Other Architectures | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| Linux and Real Time | |
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| What Is Real Time? | |
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| Soft Real Time | |
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| Hard Real Time | |
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| Linux Scheduling | |
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| Latency | |
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| Kernel Preemption | |
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| Impediments to Preemption | |
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| Preemption Models | |
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| SMP Kernel | |
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| Sources of Preemption Latency | |
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| Real-Time Kernel Patch | |
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| Real-Time Features | |
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| O(1) Scheduler | |
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| Creating a Real-Time Process | |
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| Critical Section Management | |
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| Debugging the Real-Time Kernel | |
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| Soft Lockup Detection | |
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| Preemption Debugging | |
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| Debug Wakeup Timing | |
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| Wakeup Latency History | |
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| Interrupt Off Timing | |
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| Interrupt Off History | |
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| Latency Tracing | |
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| Debugging Deadlock Conditions | |
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| Runtime Control of Locking Mode | |
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| Chapter Summary | |
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| Suggestions for Additional Reading | |
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| GNU Public License | |
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| U-Boot Configurable Commands | |
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| BusyBox Commands | |
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| SDRAM Interface Considerations | |
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| SDRAM Basics | |
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| SDRAM Refresh | |
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| Clocking | |
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| SDRAM Setup | |
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| Summary | |
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| Suggestions for Additional Reading | |
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| Open Source Resources | |
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| Sample BDI-2000 Configuration File | |
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| Index | |