读取PCI/PCIE配置空间

PCI及PCIE配置空间的读取有两种方式:

1.通过IO端口0xCF8/CFC

_outpd(0xCF8,(1 << 31) | (Bus << 16) | (Dev << 11) | (Fun << 8) | Reg )

然后就可以通过读取0xCFC-0xCFF来获取BIT0~BIT32的值

_inp(0xCFC)_inp(0xCFD)_inp(0xCFE)_inp(0xCFF)_inpw(0xCFC)_inpw(0xCFE)_inpd(0xCFC)

2.通过内存地址直接读取

Intel Chipset的PciexBaseAddress一般从Bus0 Dev0 Fun0 Reg60~64读取

address = PciexBaseAddress | (Bus << 20) | (Dev << 15) | (Fun << 12) | Reg;