Register Description
R
44
Intel
®
82925X/82925XE MCH Datasheet
Bit Access
&
Default
Description
15:11 R/W
00h
Device Number:
This field selects one agent on the PCI bus selected by the Bus
Number. When the Bus Number field is “00”, the MCH decodes the Device
Number field. The MCH is always Device Number 0 for the Host bridge entity,
Device Number 1 for the Host-PCI Express entity. Therefore, when the
Bus Number =0 and the Device Number equals 0, 1, or 2 the internal MCH
devices are selected.
This field is mapped to byte 6 [7:3] of the request header format during PCI
Express Configuration cycles and A [15:11] during the DMI configuration cycles.
10:8 R/W
000b
Function Number:
This field allows the configuration registers of a particular
function in a multi-function device to be accessed. The MCH ignores configuration
cycles to its internal devices if the function number is not equal to 0 or 1.
This field is mapped to byte 6 [2:0] of the request header format during PCI
Express Configuration cycles and A[10:8] during the DMI configuration cycles.
7:2 R/W
00h
Register Number:
This field selects one register within a particular Bus, Device,
and Function as specified by the other fields in the Configuration Address
Register.
This field is mapped to byte 7 [7:2] of the request header format during PCI
Express Configuration cycles and A[7:2] during the DMI Configuration cycles.
1:0
Reserved
3.4.2
CONFIG_DATA—Configuration Data Register
I/O Address:
0CFCh
Default Value:
00000000h
Access: R/W
Size: 32
bits
CONFIG_DATA is a 32-bit read/write window into configuration space. The portion of
configuration space that is referenced by CONFIG_DATA is determined by the contents of
CONFIG_ADDRESS.
Bit Access
&
Default
Description
31:0 R/W
0000 0000h
Configuration Data Window (CDW):
If bit 31 of CONFIG_ADDRESS is 1, any
I/O access to the CONFIG_DATA register will produce a configuration
transaction using the contents of CONFIG_ADDRESS to determine the bus,
device, function, and offset of the register to be accessed.
§
Summary of Contents for 82925X
Page 78: ...Host Bridge DRAM Controller Registers D0 F0 R 78 Intel 82925X 82925XE MCH Datasheet...
Page 98: ...EPBAR Registers Egress Port Register Summary R 98 Intel 82925X 82925XE MCH Datasheet...
Page 108: ...DMIBAR Registers Direct Media Interface DMI RCRB R 108 Intel 82925X 82925XE MCH Datasheet...
Page 156: ...Host PCI Express Graphics Bridge Registers D1 F0 R 156 Intel 82925X 82925XE MCH Datasheet...
Page 172: ...System Address Map R 172 Intel 82925X 82925XE MCH Datasheet...
Page 192: ...Electrical Characteristics R 192 Intel 82925X 82925XE MCH Datasheet...
