Intel
®
81341 and 81342—Address Translation Unit (PCI-X)
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
144
Order Number: 315037-002US
2.13
Register Definitions
Every PCI device implements its own separate configuration address space and
configuration registers. The PCI Local Bus Specification, Revision 2.3 requires that
configuration space be 256 bytes, and the first 64 bytes must adhere to a predefined
header format.
shows the PCI configuration registers,
listed by internal bus address offset.
shows the entire ATU configuration space
(including header and extended registers) and the corresponding section that describes
each register. Note that all configuration read and write transactions is accepted on the
internal bus as 32-bit transactions. Refer to
Chapter 21.0, “Peripheral Registers”
.
2.13.1
PCI Configuration Registers
The ATU is programmed via a Type 0 configuration command on the PCI interface. See
Section 2.2.1.4, “Inbound Configuration Cycle Translation” on page 69
. ATU
configuration space is function number zero of the 81341 and 81342 single-function
PCI device.
Beyond the required 64 byte header format, ATU configuration space implements
extended register space in support of the units functionality. Refer to the PCI Local Bus
Specification, Revision 2.3 for details on accessing and programming configuration
register space.
The ATU unit includes six extended capability configuration spaces beginning at
configuration offsets 90H, 98H, A0H, B0H, D0H, and E8H. The extended configuration
spaces can be accessed by a device on the PCI interface through a mechanism defined
in the PCI Local Bus Specification, Revision 2.3.
Figure 16. ATU Interface Configuration Header Format
ATU Device ID
Vendor ID
00H
Status
Command
04H
ATU Class Code
Revision ID
08H
ATUBISTR
Header Type
Latency Timer
Cacheline Size
0CH
Inbound ATU Base Address 0
10H
Inbound ATU Upper Base Address 0
14H
Inbound ATU Base Address 1
18H
Inbound ATU Upper Base Address 1
1CH
Inbound ATU Base Address 2
20H
Inbound ATU Upper Base Address 2
24H
Reserved
28H
ATU Subsystem ID
ATU Subsystem Vendor ID
2CH
Expansion ROM Base Address
30H
Reserved
Capabilities Pointer
34H
Reserved
38H
Maximum Latency
Minimum Grant
Interrupt Pin
Interrupt Line
3CH