One to four chapters experience

Chapter I.
The first chapter is a brief overview of Android system porting and driver development, and it is understood that the process of customizing the Android system for certain devices is called porting.
The first section reviews the detailed knowledge of the 4-tier architecture of Android, and I remember some of it. The second section describes the main work of Android porting, and Android porting can be divided into two parts: application porting and system porting. In this paper, the methods and reasons of system transplantation are described in detail, and the main work is: porting Linux driver and porting Hal; Section three describes two ways to view the Linux kernel, and the fourth section describes the definition rules for the Linux kernel version number, a complete kernel version number consisting of 5 parts: Major version, minor version, Revision number, fine-tuning version number, special tuning description for specific Linux systems; The fifth section summarizes the work of learning Linux drivers: Preparing a Linux system, preparing a development version, learning Gun C, learning about hardware knowledge, and constantly practicing The sixth section briefly reviews the Linux device driver, and the seventh section further understands the driver by manipulating the LEDs.
Linux drivers are only related to the Linux kernel, regardless of the Linux system used by the user, the only way to determine whether the Linux kernel is the same is to look at their kernel version number, only those five parts are exactly the same, it can be explained that the two cores are exactly the same. The biggest difference between Andorra driver development and Linux driver development is that there is one more HAL in the Android driver development process.
Chapter II
The second chapter is mainly about the construction of the Android Bottom development environment, which is basically the same as the building of the learning environment.
Build an application development environment: The first step: Install the JDK; Step two: Install the Android SDK; step three: Install Eclipse; step Fourth: Install and configure ADT; step Fifth: Create an AVD.
Install Android NDK development environment: First step: Download Android ndk; Step two: Install the CDT; step three: Compile the Android NDK program on the command line; step Fourth: Example of importing the Android Ndk; Step Fifth: Configure Android The NDK's integrated development environment.
Installs the cross-compilation environment.
Through this chapter of learning the team has previously learned a variety of environment to build more familiar and skilled, but also to the environment in the process of building a variety of problems encountered more effective solutions and higher efficiency.
Chapter III
In the third chapter, we mainly introduce the way to use Git as a source code management software.
The first section describes a few issues that git installation can encounter.
The second section describes how to view the git documentation. The help document for the specified command can be viewed directly under Linux with the Man command. After installing Git-doc, Git's text format and HTML-formatted documents are installed.
The third section explains the source code submission and acquisition, through a complete example of how to create a repository, submit source code, create a branch, upload source code to a remote server, and get source code from a remote server. The first step is to create the repository: Git init; the second step: Submit the file to the local repository, you are the owner of this local repository, access to the local repository does not require any permissions; step three: Create a local branch: Git branch, developers can create a branch of a beautiful wardrobe, The code that modifies the branch is not the main branch; Fourth step: Switch local branch: git checkout, use git checkout to switch between different local branches, and fifth step: Create an open source project on GitHub, with the files created by its hosting, Upload source code to github:git push, sixth step: Download source from GitHub: Git clone.
Git is an essential tool in the learning process for readers who want to delve deeper into the underlying technology. The best way to learn a new technology is to read the source code of interest directly, so that you can really understand the author's ideas, in the same way, to really understanding the Linux kernel is to directly read the Linux kernel source code.

Fourth Chapter
The fourth chapter mainly introduces how to download and compile the Android source code and the Linux kernel source code.
The first section is a set of Android source code download, compilation and testing. Studying the Android source code does not necessarily need to know every detail, just focus on the source of the code we need to know.
Configure Android Source code download Environment: 1th Step: Create a directory for downloading script files; step 2nd: Download the repo script file; Step 3rd: Create a directory to hold the Android source code; 4th Step: Initialize; 5th step: Start downloading Android source code.
From the structure of the Android source code can be seen, in addition to the makefile file, the rest of the directory, these directories have saved the Android source code of different sub-projects.
There are two ways to download a subproject in the Android source code: 1, use the Repo Sync command, 2, use the git clone command. The steps to compile the Android source code are as follows: 1: Initialize the compilation environment, 2, select the target, 3, compile the Android source code. To install the cross-compiler step: 1, preparation, 2, unzip the compiler, 3, verify that the cross-compiler is installed successfully, 4, install LIBNCURSES5.
Android Drive migration is primarily the porting of the Linux kernel, the migration of the Linux kernel is primarily a driver-driven migration, so in order to develop and test Linux drivers, the Android application development environment and the Linux kernel development environment are required.

One to four chapters experience