【作者】 刘红丹；

【导师】 马光胜；

【作者基本信息】 哈尔滨工程大学 ， 计算机应用技术， 2007， 硕士

【摘要】 随着计算机技术和微电子的的迅速发展，嵌入式系统已经被广泛地应用到许多领域，如科学研究、工程设计、军事技术以及各种商业应用等。嵌入式系统被定义为以应用为中心，以计算机技术为基础、软硬件可裁剪、适应于特定应用系统对功能、可靠性、成本、体积、功耗等严格要求的专业计算机系统。在目前的各种嵌入式处理器中，由于ARM芯片的低功耗、低成本等显著优点，因而获得众多的半导体厂商的大力支持，在32位嵌入式应用领域获得了巨大的成功。另一方面，Linux操作系统具有开放源代码、功能强大且易于移植等特点而成为嵌入式操作系统的首选，因此在ARM芯片上构建嵌入式Linux系统成为嵌入式领域的一个热点。本文首先总结了ARM的体系结构和特点，并选择了基于ARM920T内核的AT91RM9200开发板作为移植平台。然后介绍了嵌入式Linux系统的启动程序的实现原理，并实现了U-Boot的移植。在对Linux内核结构进行了分析后，给出Linux内核的详细的移植实现。之后在综合分析现有的Linux裁剪方法的基础上，考虑到嵌入式系统是针对具体应用的专用系统，在设计时其硬件平台和软件设计的目标已经非常明确，不会轻易变动，提出了面向应用的裁剪方法，此方法属于代码级的裁剪，能够有效去除无用代码。运用面向应用的裁剪方法在针对嵌入式Linux下的通用CD播放器的系统裁剪实验中，获得了比普通裁剪方法更高的裁剪率，从而证实该方法能更有效的减小嵌入式Linux系统的体积。本文最后详细给出了在Fedora Core 4操作系统中的SkyEye仿真平台上实现嵌入式Linux系统的过程，包括SkyEye平台的硬件仿真配置、在Fedora Core 4中嵌入式开发环境的建立以及根文件系统的构建等，最终所移植裁剪的嵌入式系统能够成功的运行。更多还原

【Abstract】 With the rapid development of computer technology and micro-electronics, embedded system is widely applied to many fields, such as scientific research, engineering design, military technology, and kinds of business applications. Embedded system is defined as a professional computer system based on computer technology which aims at applications. Its software and hardware can bu cut down. It also meets the specifical requirement, such as function, reliability, cost, volume, power dissipation. At the present time, because of lower power dissipation and lower cost of ARM’s strong suit, many manufacturers use it. ARM is more successful than other embedded processor of 32-bits. On the other hand, linux is open-sourced, easy to port and has powerful function so that it turns into the first choice of embedded system. Therefore building embedded linux system is popular.Firstly, the thesis summarizes the features of the ARM architecture. The AT91RM9200 board that based on ARM920T is choosen to be the aim platform. Afterward the Bootloader of embedded linux system is introduced. U-Boot is then ported to the aim platform. Then the thesis makes a detailed analysis at the linux kernel, and ports the kernel to the aim platform. After comprehensive analysis of the current methods to reduce Linux and considering that embedded system is the application-special system that the hardware and software are fixed in design period and almost never changed, an application-oriented method is put forward. This method is code-level so that it could remove the unused code. It is then tested in the experiment about an embedded Linux CD player system. Through the test we get the conclusion that there will be a higher reduction rate using this method than others, thus it can be more effectively to reduce the size of embedded Linux system.At last the process of building an embedded linux system on SkyEye simulator in Fedora Core 4 system is discussed, including configuring SkyEye simulator, building the embedded cross-compile environment in Fedora Core 4 system and making the root filesystem. Ultimately the embedded system ported and reduced before runs successfully.更多还原