一种面向Microsoft Windows的AMBA设备PCI虚拟化机制

A PCI Virtualization Mechanism for AMBA Devices in Microsoft Windows

PKUnity-86是基于x86处理器和AMBA开放总线架构的系统芯片,既能快速集成各种标准IP核,又支持Microsoft Windows和x86应用程序.如何使AMBA设备支持工业标准的PCI设备枚举和访问,是支持Microsoft Windows的首要问题.本文提出一种硬件VPCI机制,通过为AMBA设备实现虚拟的PCI配置空间,对配置、存储和I/O交易进行转发,Microsoft Windows就能无差别地识别位于PCI总线的标准PCI设备和位于AMBA总线上的AMBA设备,复用标准PCI设备驱动程序以访问相应的AMBA设备.在Bochs模拟器上,基于该PCI虚拟化机制的PKUnity-86系统芯片成功启动Microsoft Windows 98和Windows XP和运行典型的x86应用程序.VPCI的硬件开销仅为标准PCI的13.7%,性能优于标准PCI;读和写PCI配置空间的性能分别是AMD VSA的7.31和6.73倍.

PKUnity-86 is a system-on-chip that integrates AMBA system bus architecture with a x86 processor.A tremendous amount of standard intellectual properties from embedded world can be leveraged,as well as Microsoft Windows and x86 applications.How to identify and access AMBA devices is principal for Microsoft Windows compatibility.The paper implements a centralized PCI virtualization mechanism called VPCI,which routes configuration memory and I/O transactions to make Microsoft Window identify PCI devices on PCI bus and AMBA devices on AMBA.Standard Windows PCI device drivers can be reused directly.In Bochs simulator PKUnity-86 system-on-chip that adapts this VPCI mechanism boots up Microsoft Windows 98 and Window XP,and run typical x86 applications.The VPCI achieves better performance than standard PCI with only 13.7% hardware cost.The performance of read and write configuration space is 7.31 and 6.73 times that of AMD VSA.