XIO2000AI TAOS [TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS], XIO2000AI Datasheet - Page 63

• Manufacturer Part Number: XIO2000AI
• Description: PCI Express to PCI Bus Translation Bridge
• Manufacturer: TAOS [TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS]

4.5
4.6
4.7
4.8
April 2007 Revised October 2008
31:24
23:16
15:8
BIT
7:0
Class Code and Revision ID Register
This read-only register categorizes the base class, subclass, and programming interface of the bridge. The
base class is 06h, identifying the device as a bridge. The subclass is 04h, identifying the function as a
PCI-to-PCI bridge, and the programming interface is 00h. Furthermore, the TI device revision is indicated in
the lower byte (03h). See Table 4−4 for a complete description of the register contents.
Cache Line Size Register
This read/write cache line size register is used by the bridge to determine how much data to prefetch when
handling delayed read transactions. The value in this register must be programmed to a power of 2. Any written
odd value (bit 0 = 1b) or value greater than 32 DWORDs is treated as 0 DWORDs.
Primary Latency Timer Register
This read-only register has no meaningful context for a PCI Express device and returns the value 00h when
read.
Header Type Register
This read-only register indicates that this function has a type one PCI header. Bit 7 of this register is 0b
indicating that the bridge is a single-function device.
RESET STATE
RESET STATE
RESET STATE
RESET STATE
RESET STATE
BIT NUMBER
BIT NUMBER
BIT NUMBER
BIT NUMBER
BIT NUMBER
FIELD NAME
BASECLASS
SUBCLASS
PCI register offset:
Register type:
Default value:
PCI register offset:
Register type:
Default value:
PCI register offset:
Register type:
Default value:
PCI register offset:
Register type:
Default value:
CHIPREV
PGMIF
ACCESS
Table 4−4. Class Code and Revision ID Register Description
31
15
0
0
7
0
7
0
7
0
R
R
R
R
30
14
0
0
6
0
6
0
6
0
Base class. This field returns 06h when read, which classifies the function as a bridge device.
Subclass. This field returns 04h when read, which classifies the function as a PCI-to-PCI bridge.
Programming interface. This field returns 00h when read.
Silicon revision. This field returns the silicon revision of the function.
29
13
0
0
5
0
5
0
5
0
08h
Read-only
0604 0003
0Ch
Read/Write
00h
0Dh
Read-only
00h
0Eh
Read-only
01h
28
12
0
0
4
0
4
0
4
0
27
11
0
0
3
0
3
0
3
0
26
10
1
0
2
0
2
0
2
0
25
1
9
0
1
0
1
0
1
0
24
0
8
0
DESCRIPTION
0
0
0
0
0
1
23
0
7
0
22
0
6
0
21
0
5
0
Classic PCI Configuration Space
20
0
4
0
19
0
3
0
SCPS155C
18
1
2
0
17
0
1
1
16
0
0
1
53