Data Sheet

System Manageability—Ethernet Controller I210
645
10.4.2.3 MC-to-OS Filtering
When OS-to-MC is enabled, as with regular MC transmit traffic, the port (OS or network) to which the
packet is sent is fixed according to the source MAC address of the packet.
After that, the MC traffic will be filtered according to the L2 Host filters of the selected port (as
described in Section 7.1.1). According to the results of the filtering the packet can be forwarded to the
OS, the network or both.
The following rules apply to the forwarding of OS packets:
If MC to net is disabled, all the traffic from the MC is sent to the Host.
If MC to host is disabled, all the traffic from the MC is sent to the network.
The packet will be forwarded only according to the destination MAC address and VLAN tag.
Unicast packets that matches one of the exact filters (RAH/RAL) are sent only to the Host. Other
packets that passes the L2 Host filtering will be sent to both the Host and the network. Packets that do
not pass the L2 filtering are sent only to the network.
10.4.2.4 Queuing of packets received from the MC.
Packets received from the MC are queued in the default queue.
10.4.2.5 Offloads of packets received from the MC.
Packets received from the MC and forwarded to the OS do not pass the same path as regular network
packets. Thus parts of the offloads provided for the network packets are not available for the MC
packets. Packet received from the MC are identified by the RDESC.STATUS.MC bit.
The following list describes which offloads are available for MC packets:
• CRC is checked and removed on the MC packets. The RDESC.STATUS.Strip CRC will always be set
for these packets.
• The RSS type and RSS hash are not calculated for MC packets and are always set to zero.
• The header of MC packets is never split.
• A fragmented MC packet will not be detected by the hardware.
• The MC packets are not detected as time sync packet. The RDESC.STATUS.TS will always be clear
for these packets.
• The L3 and L4 checksum are not performed on these packets. The L4I, IPCS, UDPCS, and UDPV
fields will always be cleared for these packets.
• In systems where the double VLAN feature is enabled (CTRL_EXT.EXT_VLAN is set), the VEXT bit is
valid for MC packets.
Note: In systems that uses double VLAN, the MC is expected to send all packets (apart from NC-SI
commands) with the outer VLAN included. Failing to do so may cause corruptions to the
packet received by the OS
•The RDESC.ERRORS field is always cleared for these packets.
Note: Traffic sent from the MC will not cause a PME event, even if it matches one of the wake-up
filters set by the port.