Datasheet

KSZ8795CLX
DS00002112B-page 40  2016-2017 Microchip Technology Inc.
Advanced VLAN features are also supported in KSZ8795CLX, such as “VLAN ingress filtering” and “discard non PVID”
defined in bits [6:5] of the Port Control 2 Register. These features can be controlled on a per port basis.
3.6.9 RATE LIMITING SUPPORT
The KSZ8795CLX provides a fine resolution hardware rate limiting based on both bps (bit per second) and pps (packet
per second).
For bps, the rate step is 64 Kbps when the rate limit is less than 1Mbps rate for 100BT or 10BT, and 640 Kbps for 1000.
The rate step is 1Mbps when the rate limit is more than 1Mbps rate for 100BT or 10BT, 10 Mbps for 1000.
For pps, the rate step is 128 pps (besides the 1st one which is 64 pps) when the rate limit is less than 1Mbps rate for
100BT or 10BT, and 1280 pps (except the 1st one of 640 pps) for 1000. The rate step is 1Mbps when the rate limit is
more than 1.92 Kpps rate for 100BT or 10BT, 19.2 Kpps for 1000 (refer to Tab le 3-1 8).
The pps limiting is bounded by the bps rate for each pps setting. The mapping is shown in the 2nd column of Ta b l e 3-18 .
Yes 1 No Yes Send to the destination port defined in
the Dynamic MAC Address Table
Bits[58:56].
Yes 1 Yes Don’t Care Send to the destination port(s) defined
in the Static MAC Address Table
bits[52:48].
TABLE 3-17: FID+SA LOOK-UP IN VLAN MODE
FID+SA Found in Dynamic MAC
Table?
Action
No The FID+SA will be learned into the dynamic table.
Yes Time stamp will be updated.
TABLE 3-18: 10/100/1000 MBPS RATE SELECTION FOR THE RATE LIMIT
Item
Bps Bound
of pps
(Egress Only)
10 Mbps 100 Mbps 1000 Mbps
7d’0 7d’0 19.2 Kpps 10 Mbps 19.2 Kpps 100 Mbps 1.92 Mpps 1000 Mbps
7d’1 -
7d’10
7d’3, 6, (8x)10 1.92 Kpps
x code
1Mbps
x code
1.92 Kpps
x code
1Mbps
x code
19.2 Kpps
x code
10 Mbps
x code
7d’11 -
7d’100
7d’11 - 7d’100 — 10 Mbps 1.92 Kpps
x code
1Mbps
x code
19.2 Kpps
x code
10 Mbps
x code
7d’101 7d’102 64 pps 64 Kbps 64 pps 64 Kbps 640 pps 640 Kbps
7d’102 7d’104 128 pps 128 Kbps 128 pps 128 Kbps 1280 pps 1280 Kbps
7d’103 7d’108 256 pps 192 Kbps 256 pps 192 Kbps 2560 pps 1920 Kbps
7d’104 7d’112 384 pps 256 Kbps 384 pps 256 Kbps 3840 pps 2560 Kbps
7d’105 7d’001 512 pps 320 Kbps 512 pps 320 Kbps 5120 pps 3200 Kbps
7d’106 7d’001 640 pps 384 Kbps 640 pps 384 Kbps 6400 pps 3840 Kbps
7d’107 7d’001 768 pps 448 Kbps 768 pps 448 Kbps 7680 pps 4480 Kbps
7d’108 7d’002 896 pps 512 Kbps 896 pps 512 Kbps 8960 pps 5120 Kbps
7d’109 7d’002 1024 pps 576 Kbps 1024 pps 576 Kbps 10240 pps 5760 Kbps
7d’110 7d’002 1152 pps 640 Kbps 1152 pps 640 Kbps 11520 pps 6400 Kbps
7d’111 7d’002 1280 pps 704 Kbps 1280 pps 704 Kbps 12800 pps 7040 Kbps
7d’112 7d’002 1408 pps 768 Kbps 1408 pps 768 Kbps 14080 pps 7680 Kbps
7d’113 7d’003 1536 pps 832 Kbps 1536 pps 832 Kbps 15360 pps 8320 Kbps
TABLE 3-16: FID+DA LOOK-UP IN VLAN MODE (CONTINUED)
DA Found in
Static MAC
Table?
Use FID Flag? FID Match?
FID+DA Found in
Dynamic MAC
Table?
Action