Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
445
Messaging Unit—Intel
®
81341 and 81342
4.9.24
MU Upper Base Address Register - MUUBAR
The MU Upper Base Address Register (MUUBAR) contains the upper 4-bit of the 36-bit
local memory base address of the MU address space as depicted in
. For
example, the MU address space as viewed from Host I/O Interface interface. The MU
base address is required to be located on a 8-KByte boundary. The lower 32-bits of the
MU Base Address are located in the MU Upper Address Register (MUBAR). Refer to
Section 4.9.23, “MU Base Address Register - MUBAR” on page 444
.
Note:
The default values of MUBAR/MUBAR are programmed to match the default values
programmed in the Inbound ATU Translate Value Register 0 - IATVR0/Inbound ATU
Upper Translate Value Register 0 - IAUTVR0. This allows the MU registers to be mapped
in the first 8-KByte of the PCI Window 0 Address space.
Table 288. MU Upper Base Address Register - MUUBAR
Bit
Default
Description
31:04
0000000H Reserved
03:00
0H
MU Upper Base Address - Local memory address of the MU (including MSI-X) registers as viewed from
Host I/O Interface. The MU occupies a 8-KByte space from Host I/O Interface.
PCI
IOP
Attributes
Attributes
28
24
20
16
12
8
4
0
31
rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rv rw rw rw rw
na
na na na na na na na na na na na na na na na
na na na
na na na na na na na na na na na na
na
Attribute Legend:
RV = Reserved
PR = Preserved
RS = Read/Set
RW = Read/Write
RC = Read Clear
RO = Read Only
NA = Not Accessible
MUUBAR
internal bus address offset
4088H