Compaq 850 manual PCI Configuration, LPC Bridge Configuration Registers ICH, Function 0, Device

Chapter 4 System Support

4.2.7 PCI CONFIGURATION

PCI bus operations require the configuration of certain parameters such as PCI IRQ routing, DMA channel configuration, RTC control, port decode ranges, and power management options. These parameters are handled by the LPC I/F bridge function (PCI function #0, device 31) of the ICH component and configured through the PCI configuration space registers listed in Table 4-3. Configuration is provided by BIOS at power-up but re-configurable by software.

Table 4-3.LPC Bridge Configuration Registers (ICH, Function 0)

Table 4-3.

LPC Bridge Configuration Registers

(ICH, Function 0, Device 31)

PCI			PCI
Config.		Reset	Config.		Reset
Addr.	Register	Value	Addr.	Register	Value
00, 01h	Vendor ID	8086h	8Ah	Device 31 Error Status	00h
02, 03h	Device ID	2410h	90, 91h	PCI DMA Configuration	0000h
04, 05h	Command	000Fh	A0-CFh	Power Management
06, 07h	Status	0280h	D0-D3h	General Control	0’s
08h	Revision ID	00h	D4-D7h	General Status	F00h
0A-0Bh	Class Code	0106h	D8h	RTC Configuration	00h
0Eh	Header Type	80h	E0h	LPC COM Port Dec. Range	00h
40-43h	ACPI Base Address	1	E1h	LPC FDD & LPT Dec. Rge	00h
44h	ACPI Control	00h	E2h	LPC Audio Dec. Range	80h
4E, 4Fh	BIOS Control	0000h	E3h	FWH Decode Enable	FFh
54h	TCO Control	00h	E4, E5h	LPC I/F Decode Range 1	0000h
58-5Bh	GPIO Base Address	1	E6, E7h	LPC I/F Enables	0000h
5Ch	GPIO Control	00h	E8h	FWH Select	00
60-63h	INTA-D Routing Cntrl.	80h [1]	EC, EDh	LPC I/F Decode Range 2	0000h
64h	Serial IRQ Control	10h	EE, EFh	Reserved	--
65-87h	Reserved	--	F0h	Reserved	--
88h	Dev. 31 Error Config.	00h	F2h	Function Disable Register	00h

NOTE:

[1] Value for each byte.

Assume unmarked locations/gaps as reserved.

4-8Compaq Deskpro EXS and Workstation 300 Personal Computers

Featuring the Intel Pentium 4 Processor

First Edition - December 2000