KSZ8795CLX
TABLE 4-4:
Address
6
PORT REGISTERS (CONTINUED)
Name
Description
Mode
Default
DiffServ Priority
Classification Enable
1 = Enable DiffServ priority classification for
ingress packets on port.
R/W
0
0 = Disable DiffServ function.
5
802.1p Priority
Classification Enable
1 = Enable 802.1p priority classification for ingress
packets on port.
0 = Disable 802.1p priority classification for ingress
packets on port.
R/W
R/W
0
4 – 3
Port-Based Priority
Classification Enable
00 = Ingress packets on Port will be classified as
priority 0 queue if “Diffserv” or “802.1p” classifica-
tion is not enabled or fails to classify.
00
01 = Ingress packets on port will be classified as
priority 1 queue if “Diffserv” or “802.1p” classifica-
tion is not enabled or fails to classify.
10 = Ingress packets on port will be classified as
priority 2 queue if “Diffserv” or “802.1p” classifica-
tion is not enabled or fails to classify.
11 = Ingress packets on port will be classified as
priority 3 queue if “Diffserv” or “802.1p” classifica-
tion is not enabled or fails to classify.
Note: “DiffServ”, “802.1p” and port priority can be
enabled at the same time. The OR’ed result of
802.1p and DSCP overwrites the Port priority.
2
Tag insertion
Tag Removal
1 = When packets are output on the port, the switch
will add 802.1q tags to packets without 802.1q tags
when received. The switch will not add tags to
packets already tagged. The tag inserted is the
ingress port’s “Port VID.”
R/W
0
0 = Disable tag insertion.
1
0
1 = When packets are output on the port, the switch
will remove 802.1q tags from packets with 802.1q
tags when received. The switch will not modify
packets received without tags.
R/W
R/W
0
0
0 = Disable tag removal.
Two Queues Split Enable This Bit[0] in Registers16/32/48/64/80 should be in
combination with Registers177/193/209/225/241
Bit[1] for Ports 1 5. This will select the split of 1, 2,
and 4 queues:
For Port 1, Register 177 Bit[1], Register 16 Bit[0]:
11 = Reserved
10 = The port output queue is split into four priority
queues or if map 802.1p to priority 0 3 mode.
01 = The port output queue is split into two priority
queues or if map 802.1p to priority 0 3 mode.
00 = Single output queue on the port. There is no
priority differentiation even though packets are
classified into high or low priority.
DS00002112A-page 54
2016 Microchip Technology Inc.
MICREL [ MICREL SEMICONDUCTOR ]
