Bitfields for PCI Configuration Base Address:
Bit(s)	Description	)
 0	address type (0 = memory space, 1 = I/O space)
---memory address---
 2-1	address type
	00 anywhere in first 4GB
	01 below 1MB
	10 anywhere in 64-bit address space
	11 reserved
 3	prefetchable
 31-4	bits 31-4 of base memory address if addressable in first 1MB or 4GB
 63-4	bits 63-4 of base memory address if addressable in 64-bit memory
	(bits 63-32 are stored in the following base address DWORD)
---I/O address---
 1	reserved
 31-2	bits 31-2 of base I/O port
SeeAlso: #00878,#00902