Yocto Project Linux Kernel Development Manual

Table of Contents

• 1 Introduction
  • 1.1 Overview
  • 1.2 Kernel Modification Workflow
• 2 Common Tasks
  • 2.1 Preparing the Build Host to Work on the Kernel
    • 2.1.1 Getting Ready to Develop Using devtool
    • 2.1.2 Getting Ready for Traditional Kernel Development
  • 2.2 Creating and Preparing a Layer
  • 2.3 Modifying an Existing Recipe
    • 2.3.1 Creating the Append File
    • 2.3.2 Applying Patches
    • 2.3.3 Changing the Configuration
    • 2.3.4 Using an “In-Tree”  defconfig File
  • 2.4 Using devtool to Patch the Kernel
  • 2.5 Using Traditional Kernel Development to Patch the Kernel
  • 2.6 Configuring the Kernel
    • 2.6.1 Using  menuconfig
    • 2.6.2 Creating a  defconfig File
    • 2.6.3 Creating Configuration Fragments
    • 2.6.4 Validating Configuration
    • 2.6.5 Fine-Tuning the Kernel Configuration File
  • 2.7 Expanding Variables
  • 2.8 Working with a “Dirty” Kernel Version String
  • 2.9 Working With Your Own Sources
  • 2.10 Working with Out-of-Tree Modules
    • 2.10.1 Building Out-of-Tree Modules on the Target
    • 2.10.2 Incorporating Out-of-Tree Modules
  • 2.11 Inspecting Changes and Commits
    • 2.11.1 What Changed in a Kernel?
    • 2.11.2 Showing a Particular Feature or Branch Change
  • 2.12 Adding Recipe-Space Kernel Features
• 3 Working with Advanced Metadata (yocto-kernel-cache)
  • 3.1 Overview
  • 3.2 Using Kernel Metadata in a Recipe
  • 3.3 Kernel Metadata Syntax
    • 3.3.1 Configuration
    • 3.3.2 Patches
    • 3.3.3 Features
    • 3.3.4 Kernel Types
    • 3.3.5 BSP Descriptions
      • 3.3.5.1 Description Overview
      • 3.3.5.2 Example
  • 3.4 Kernel Metadata Location
    • 3.4.1 Recipe-Space Metadata
    • 3.4.2 Metadata Outside the Recipe-Space
  • 3.5 Organizing Your Source
    • 3.5.1 Encapsulating Patches
    • 3.5.2 Machine Branches
    • 3.5.3 Feature Branches
  • 3.6 SCC Description File Reference
• 4 Advanced Kernel Concepts
  • 4.1 Yocto Project Kernel Development and Maintenance
  • 4.2 Yocto Linux Kernel Architecture and Branching Strategies
  • 4.3 Kernel Build File Hierarchy
  • 4.4 Determining Hardware and Non-Hardware Features for the Kernel Configuration Audit Phase
• 5 Kernel Maintenance
  • 5.1 Tree Construction
  • 5.2 Build Strategy
• 6 Kernel Development FAQ
  • 6.1 Common Questions and Solutions
    • 6.1.1 How do I use my own Linux kernel .config file?
    • 6.1.2 How do I create configuration fragments?
    • 6.1.3 How do I use my own Linux kernel sources?
    • 6.1.4 How do I install/not-install the kernel image on the rootfs?
    • 6.1.5 How do I install a specific kernel module?
    • 6.1.6 How do I change the Linux kernel command line?

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