Format of PCI Configuration Data for Intel 82371AB (PIIX4), Power Management:
Offset	Size	Description	)
 00h 64 BYTEs	header (see #00878)
		(vendor ID 8086h, device ID 7113h)
 40h	DWORD	base address of power-management I/O ports
		(same format as PCI base addresses; low bit hardwired to 1)
 44h	DWORD	initial counts of device 0-11 idle timers
 48h	DWORD	!!!intel\29056201.pdf p.117
 4Ch	DWORD	general-purpose input control
 50h  3 BYTEs	"device resource D"
 53h	BYTE	unused???
 54h	DWORD	device activity event selection A
 58h	DWORD	device activity event selection B
 5Ch	DWORD	"device resource A"
 60h	DWORD	"device resource B"
 64h	DWORD	"device resource C"
 68h  3 BYTEs	"device resource E"
 6Bh  5 BYTEs	unused???
 70h  3 BYTEs	"device resource G"
 73h	BYTE	unused???
 74h	DWORD	"device resource H"
 78h	DWORD	"device resource I"
 7Ch	DWORD	"device resource J"
 80h	BYTE	miscellaneous power management
 81h 15 BYTEs	unused???
 90h	DWORD	base address for SMBus I/O ports
		(same format as PCI base addresses; low bit hardwired to 1)
 94h	...
 D2h	BYTE	SMBus host configuration
 D3h	BYTE	SMBus slave command
 D4h	BYTE	SMBus slave shadow port 1 address
 D5h	BYTE	SMBus slave shadow port 2 address
 D6h	BYTE	SMBus revision
 D7h
SeeAlso: #00873,#01100,#01103,#01104