Intel
®
81341 and 81342—Peripheral Registers
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
1042
Order Number: 315037-002US
21.6.2.1 Address Translation Unit (PCI-X)
A subset of the ATU registers are accessible through both inbound PCI configuration
cycles and the 81341 and 81342 core CPU (Register offsets 000H through 0FFH). The
balance of the registers are accessible only via the internal bus.
The Internal Bus Address Offset to PMMRBAR of any ATU Register can be derived by
adding the 4 KB address aligned Internal Bus Memory Mapped Register Range Offset
(
Table 666, “81341 and 81342 ATUX Configuration Space Base Address Offset” on
) to the Register Offset (
Table 667, “Address Translation Unit Registers —
For example, when INTERFACE_SEL_PCIX# is asserted, the offset to PMMRBAR of the
ATU Command Register would be (4 C000H+004H) or 4 C004H.
Note:
The 4 KB Address Aligned Range Offset can be different depending on two configuration
straps as described in
.
Table 666. 81341 and 81342 ATUX Configuration Space Base Address Offset
INTERFACE_SEL_PCIX#
ATUX Base Address Offset (Relative to PMMRBAR)
PCI Attributes
Asserted
+4 0000H
Deasserted
+4 4000H
Local Attributes
Asserted
+4 8000H
Deasserted
+4 C000H