Intel
®
81341 and 81342—Address Translation Unit (PCI Express)
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
376
Order Number: 315037-002US
3.16.92 Outbound I/O Base Address Register - OIOBAR
The OIOBAR register locates the 64 KB I/O cycle address window in the 81341 and
81342’s 64 Gbyte internal address space. When A[35:16] of the internal bus address
matches the value in OIOBAR, the ATU claims the transaction and forward it over to the
PCI interface as an I/O cycle.
Note:
In translating the internal bus address A[35:0] for the PCI bus I/O cycle, A[15:0] is
forwarded over to the PCI bus unmodified while A[31:16] is replaced with the bits
31:16 from the
“Outbound I/O Window Translate Value Register - OIOWTVR”
.
Table 226. Outbound I/O Base Address Register - OIOBAR
Bit
Default
Description
31:12
0 FFFDH
Outbound I/O Base Address - This value represents bits 35 to 16 of the internal bus address used to
claim an outbound I/O cycle request for the ATU.
11:3
000H
Reserved
2:0
000
Outbound I/O Function Number Mapping - The Function number in this field is used as part of the
Requestor ID for outbound I/O transactions.
PCI
IOP
Attributes
Attributes
28
24
20
16
12
8
4
0
31
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rv
rw
rw
rw
rw
rw
rw
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
+300H