450NX Datasheet, PDF (68/248 Pages) Intel Corporation – Intel 450NX PCIset

3. Register Descriptions
3.4.8
GAPEN: Gap Enables
Address Offset: 60h
Default Value: 0Eh
Size:
8 bits
Attribute: Read/Write
This register controls the enabling of the two programmable memory gaps, and several fixed-
size/fixed-location spaces. This register applies to both host-initiated transactions and PCI-
initiated inbound transactions, and is therefore duplicated in both the MIOC and PXB
Configuration Spaces. Software must ensure that both sets are programmed identically to
achieve correct functioning. See the MIOC Configuration Space for a detailed description.
3.4.9
HDR: Header Type Register
Address Offset: 0Eh
Default Value: 00h
Size:
8 bits
Attribute: Read Only
Bits Description
7
Multi-function Device.
Selects whether this is a multi-function device, that may have alternative
configuration layouts. This bit is hardwired to 0.
6:0 Configuration Layout.
This field identifies the format of the 10h through 3Fh space. This field is hardwired
to 00h, which represents the default PCI configuration layout.
3.4.10 HXGB: High Expansion Gap Base
Address Offset: 58-5Ah
Default Value: 000000h
Size:
24 bits
Attribute: Read/Write
This register defines the starting address of the High Expansion Gap (HXG). This register
applies to both host-initiated transactions and PCI-initiated inbound transactions, and is
therefore duplicated in both the MIOC and PXB Configuration Spaces. Software must ensure
that both sets are programmed identically to achieve correct functioning. See the MIOC
Configuration Space for a detailed description.
3.4.11 HXGT: High Expansion Gap Top
Address Offset: 5C-5Eh
Default Value: 000000h
Size:
24 bits
Attribute: Read/Write
This register defines the highest address of the High Expansion Gap (HXG), above. HXGT
applies to both host-initiated transactions and PCI-initiated inbound transactions, and is
therefore duplicated in both the MIOC and PXB Configuration Spaces. Software must ensure
that both sets are programmed identically to achieve correct functioning. See the MIOC
Configuration Space for a detailed description.
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Intel® 450NX PCIset