KSZ8895MQ_12 MICREL [Micrel Semiconductor], KSZ8895MQ_12 Datasheet - Page 75

• Manufacturer Part Number: KSZ8895MQ_12
• Description: Integrated 5-Port 10/100 Managed Ethernet Switch with MII/RMII interface
• Manufacturer: MICREL [Micrel Semiconductor]

Micrel, Inc.
Advanced Control Registers (Continued)
The registers 128, 129 can be used to map from 802.1p priority field 0-7 to switch’s four priority queues 0-3, 0x3 is highest priority
queues as priority 3, 0x0 is lowest priority queues as priority 0.
March 2012
Address
Register 128 (0x80): Global Control 12
7 – 6
5 – 4
3 – 2
1 – 0
Register 129 (0x81): Global Control 13
7 – 6
5 – 4
3 – 2
1 – 0
Register 130 (0x82): Global Control 14
7 – 6
5
4
3 – 2
1
Tag_0x3
Tag_0x2
Tag_0x1
Tag_0x0
Tag_0x7
Tag_0x6
Tag_0x5
Tag_0x4
Pri_2Q[1:0]
(Note that program
Prio_2Q[1:0] = 01 is not
supported and should be
avoided)
Reserved
Reserved
Reserved
Reserved
Name
Description
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x3.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x2.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x1.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x0.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x7.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x6.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x5.
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x4.
When the 2 Queues configuration is selected, these
Pri_2Q[1:0] bits are used to map the 2-bit result of
IEEE 802.1p from register 128/129 or TOS/DiffServ
from register 144- 159 mapping (for 4 Queues) into
two queues low/high priorities.
2-bit result of IEEE 802.1p or TOS/DiffServ
00 (0) = map to Low priority queue
01 (1) = Prio_2Q[0] map to Low/High priority queue
10 (2) = Prio_2Q[1] map to Low/High priority queue
11 (3) = map to High priority queue
Pri_2Q[1:0] =
00: Result 0,1,2 are low priority. 3 is high priority.
10: Result 0,1 are low priority. 2,3 are high priority
(default).
11: Result 0 is low priority. 1,2,3 are high priority.
N/A Do not change.
N/A Do not change.
N/A Do not change.
N/A Do not change.
75
Mode
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
KSZ8895MQ/RQ/FMQ
RO
RO
RO
RO
M9999-032612-1.5
Default
0x1
0x1
0x0
0x0
0x3
0x3
0x2
0x2
10
01
0
0
0