XIO2000AI TAOS [TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS], XIO2000AI Datasheet - Page 123

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

5.22 VC Resource Control Register (VC0)
April 2007 Revised October 2008
30:27
26:24
23:20
19:17
15:8
BIT
7:0
31
16
The VC resource control register for VC0 allows software to control VC0 and the associated port and
arbitration schemes supported by the bridge. See Table 5−18 for a complete description of the register
contents.
PORT_ARB_SELECT
RESET STATE
RESET STATE
LOAD_PORT_TABLE
BIT NUMBER
BIT NUMBER
PCI Express extended register offset:
Register type:
Default value:
FIELD NAME
TC_VC_MAP
VC_EN
VC_ID
RSVD
RSVD
RSVD
Table 5−18. VC Resource Control Register (VC0) Description
31
15
1
0
ACCESS
30
14
RW
0
0
R
R
R
R
R
R
R
29
13
0
0
VC enable. This field is internally hardwired to 1b to indicate that this VC resource is always
enabled.
Reserved. Returns 0h when read.
Virtual channel ID. This field is internally hardwired to 000b to indicate that this VC resource
is always used for VC0.
Reserved. Returns 0h when read.
Port arbitration select. This read-only field returns 000b when read, because only
hardware-fixed, round-robin arbitration is supported for this VC.
Load port arbitration table. This read-only bit returns 0b when read, because no port
arbitration table is supported for this VC.
Reserved. Returns 00h when read.
TC/VC map. This field indicates all of the traffic classes that are mapped to this VC. A 1b in
any bit position indicates that the corresponding traffic class is enabled for this VC. A 0b
indicates that the corresponding traffic class is mapped to a different VC. The following table
is used:
Bit 0 = Traffic class 0 (This bit is read-only and returns a value of 1b)
Bit 1 = Traffic class 1
Bit 2 = Traffic class 2
Bit 3 = Traffic class 3
Bit 4 = Traffic class 4
Bit 5 = Traffic class 5
Bit 6 = Traffic class 6
Bit 7 = Traffic class 7
The default value of FFh indicates that all eight traffic classes are initially mapped to VC0.
28
12
0
0
27
11
0
0
26
10
0
0
Read-only, Read/Write
164h
8000 00FFh
25
0
9
0
24
0
8
0
DESCRIPTION
23
0
7
1
PCI Express Extended Configuration Space
22
0
6
1
21
0
5
1
20
0
4
1
19
0
3
1
SCPS155C
18
0
2
1
17
0
1
1
16
0
0
1
113