【作者】 丰大强；

【导师】 吴少刚；

【作者基本信息】 中国石油大学 ， 计算机应用技术， 2009， 硕士

【摘要】 随着信息技术的发展,嵌入式操作系统的研究与开发已成为新的发展方向。嵌入式操作系统WindowsCE以其操作方式简便、界面友好和支持多种文件格式等优点,广泛应用于嵌入式领域。本文基于龙芯2E处理器,实现Windows CE在龙芯平台上的移植和优化。WindowsCE移植与优化流程中,BSP(BoardSupportPackage,板级支持包)的开发是工作重点,同时,也是本课题研究的主要工作。BSP是介于硬件平台与WindowsCE操作系统之间的一层软件系统,是操作系统的一部分。BSP的主要功能是将WindowsCE操作系统与硬件平台交互的接口抽象出来,作为单独的一层函数,操作系统访问底层硬件时不再直接访问硬件平台。BSP主要由:OEM抽象层(OEMAbstractionLayer,OAL)、引导程序(BootLoader)、设备驱动程序及配置文件4部分构成。开发BSP的主要工作是Boot Loader与OAL的设计与实现。Windows CE操作系统下Boot Loader的基本功能是初始化硬件平台、加载操作系统映像文件。Windows CE操作系统下OAL的主要功能是把操作系统内核对硬件的访问功能抽象出来,形成一些接口函数或库。当操作系统需要访问硬件时,可直接调用这些抽象出来的接口函数或库。在开发环境中编译生成Windows CE操作系统的映像文件,还需编写必要的.BIB、.REG、Source及DIRS等配置文件;然后进行平台定制,根据龙芯硬件平台的特点定制操作系统必要的模块;最终在开发环境中编译、链接生成最终的操作系统映像文件。本课题结合龙芯2E处理器体系结构及Windows CE操作系统页式管理的特点,对龙芯2E平台的缓存管理进行了实现与优化。优化后的系统及应用程序整体性能提高了约20%,基于龙芯2E平台缓存功能的实现和优化取得了比较理想的效果。本文设计实现的Windows CE嵌入式操作系统已稳定、高效的运行在龙芯2E开发板上,对于龙芯处理器在嵌入式领域的扩展具有广泛的应用价值和指导意义。更多还原

【Abstract】 With the development of information technology, the research and development of embeddedoperating system has become the new direction.Owning the advantages of simple operation, friendlyinterface and supporting a variety of file formats, the embedded operating system Windows CE has beenused in embedded system field widely.This paper achieves the transplantation and optimization ofWindowsCEonLoongsonplatformbasedontheLoongson2Eprocessor.In the process of the Windows CE transplantation and Optimization, developing the BSP (BoardSupportPackage)isthepivotandalsothe mainworkoftheresearchatthesame time.TheBSPisalayerof software systemwhich is between the hardware platformand the Windows CE operating system, and isapartoftheoperatingsystem.OneofthemainfunctionsofBSPistoabstractouttheinterfaceswheretheWindows CE operating system interacts with the hardware platform as a single layer of functions so thatthe operating system may not access the hardware platform directly when accessing the bottomhardware.The BSPis mainlycomposed of 4 parts, the OEM Abstraction Layer (OAL), the Boot Loader,the Device Drivers and the Configuration Files.The main task of developing BSP is the design andimplementation of the BootLoader and the OAL.The basic function ofBoot Loader in the Windows CEoperatingsystemistoinitializethehardwareplatformandloadtheoperatingsystemimagefiles.Themainfunction of OAL in Windows CE operating system is to abstract out the way that the operating systemkernel accesses the hardware so as to form a number of interface functions and libraries, which can bedirectly called when the operating system needs to access the hardware.To generate the Windows CEoperating system image file in developing environment through compiling, needs to write thenecessary .BIB, .REG, Source and DIRS configuration files, then to customize the platform, necessarymodules of the operating system according to the features of the Loongson’s hardware platform, andeventually to generate the final operating system image file in the developing environment throughcompilingandlinking.Combined with the Loongson 2E processor architecture and the page management feature of Windows CE, this paper achieves the implementation and optimization on the platform of Loongson 2Eprocessor cache management.The overall performance of the optimized system and application programhas been improved by about 20% and satisfactory result has been got by the implementation andoptimizationofLoongson2Eplatformcachemanagement.In this paper, Windows CE embedded operating system has operated stably and efficiently on theLoongson 2E develop board, which has wide application value and directive significance for expansion ofLoongsonprocessinembeddedsystemfield.更多还原