Specifications

Micrel, Inc.
KSZ8895MQ/RQ/FMQ
Advanced Control Registers (Continued)
Address Name Description Mode Default
4–0
Unknown IP multicast packet
forward port map
00000 = filter unknown IP multiicast packet
00001 = forward unknown IP multicast packet to
port 1.
00010 = forward unknown IP multicast packet to
port 2.
00011 = forward unknown IP multicast packet to
port 1, port 2
……
11111 = broadcast unknown IP multicast packet to
all ports
R/W 00000
Register 135 (0x87): Global Control 19
7 Reserved N/A Do not change. RO 0
6 Reserved N/A Do not change. RO 0
5–4 Ingress Rate Limit Period
The unit period for calculating Ingress Rate Limit
00 = 16 ms
01 = 64 ms
1x = 256 ms
R/W 01
3
Queue-based Egress Rate
Limit Enabled
Enable Queue-based Egress Rate Limit
0 = port-base Egress Rate Limit (default)
1 = queue-based Egress Rate Limit
R/W 0
2
Insertion Source Port PVID
Tag Selection Enable
1 = enable source port PVID tag insertion or non-
insertion option on the egress port for each source
port PVID based on the ports registers control 8.
0 = disable, all packets from any ingress port will be
inserted PVID based on port register control 0 bit 2.
R/W 0
1–0 Reserved N/A Do not change RO 00
Register 144 (0x90): TOS Priority Control Register 0
The Ipv4/Ipv6 TOS priority control registers implement a fully decoded 64 bit differentiated services code point (DSCP) register used to
determine priority from the 6 bit TOS field in the IP header. The most significant 6 bits of the TOS field are fully decoded into 64
possibilities, and the singular code that results is mapped to the value in the corresponding bit in the DSCP register.
7–6 DSCP[7:6]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits[7:2] of the frame’s IP TOS/DiffServ/Traffic
Class value is 0x03
R/W 00
5–4 DSCP[5:4]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits[7:2] of the frame’s IP TOS/DiffServ/Traffic
Class value is 0x02
R/W 00
3–2 DSCP[3:2]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits[7:2] of the frame’s IP TOS/DiffServ/Traffic
Class value is 0x01
R/W 00
March 12, 2014
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Revision 1.7