Intel
®
81341 and 81342—Address Translation Unit (PCI Express)
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
346
Order Number: 315037-002US
3.16.57 PCI Express Capabilities Register - PCIE_CAP
This register controls various modes and features of ATU and Message Unit when
operating in the PCI Express mode.
Table 191. PCI Express Capabilities Register PCIE_CAP
Bit
Default
Description
15:14
00
2
Preserved
13:9
00000
Interrupt Message Number - 81341 and 81342 uses a single interrupt message.
This register is hardcoded to 0.
8
Endpoint: 0
Root
Complex: 1
Slot Implemented - Indicates that the PCI Express Link associated with this port is connected to a slot.
Only valid for root complex and switch downstream ports.
Hard-wired to 0
Set to 1 for root complex this bit is initialized via strapping options.
7:4
0000
or
0100
Device/Port Type - Indicates the type of PCI Express logical device.
0000b - PCI Express Endpoint device
0100b - Root Port of PCI Express Root Complex these bits are initialized via strapping options.
3:0
1H
Capability Version - Indicates PCI-SIG defined PCI Express capability structure version number
81341 and 81342 supports version 1h.
PCI
IOP
Attributes
Attributes
15
12
8
4
0
pr
pr
pr
pr
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
ro
Attribute Legend:
RV = Reserved
PR = Preserved
RS = Read/Set
RW = Read/Write
RC = Read Clear
RO = Read Only
NA = Not Accessible
Internal Bus Address Offset
+0D2H