82598EB Datasheet, PDF (217/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - Receive Functionality
3.5.2.1.1.1 Unicast Filter
The entire MAC address is checked against the 16 host unicast addresses and four management unicast
addresses (if enabled). The 16 host unicast addresses are controlled by the host interface (the BMC
must not change them). The other four addresses are dedicated to management functions and are only
accessed by the BMC. The destination address of incoming packets must exactly match one of the pre-
configured host address filters or the manageability address filters. These addresses can be unicast or
multicast. Those filters are configured through Receive Address Low – RAL (0x05400 + 8*n[n=0..15];
RW), Receive Address High – RAH (0x05404 + 8*n[n=0..15]; RW), Manageability MAC Address Low –
MMAL (0x5910 + 8*n[n=0..3]; RW) and Manageability MAC Address High – MMAH (0x5914 +
8*n[n=0..3]; RW) registers.
Promiscuous Unicast – Receive all unicasts. Promiscuous unicast mode can be set/cleared only through
the host interface (not by the BMC), and it is usually used when the 82598 is used as a sniffer.
3.5.2.1.1.2 Multicast Filter (Partial)
The 12-bit portion of an incoming packet multicast address must exactly match Multicast Filter Address
in order to pass the Multicast Filter. Those 12 bits out of the 48 bits of Destination Address can be
selected by the MO field. These entries can be configured only by the host interface and cannot be
controlled by the BMC.
Promiscuous Multicast – Receive all multicasts. Promiscuous multicast mode can be set/cleared only
through the host interface (not by the BMC), and it is usually used when the 82598 is used as a sniffer.
3.5.2.1.2 VLAN Filtering
Figure 3-22 shows VLAN filtering. A receive packet that successfully passed L2 layer filtering is then
subjected to VLAN header filtering:
1. If the packet does not have a VLAN header, it passes to the next filtering stage.
2. If the packet has a VLAN header and it passes a valid manageability VLAN filter, then is passes to
the next filtering stage.
3. If the packet has a VLAN header, it did not match step 2, and no host VLAN filters are enabled, the
packet is forwarded to the next filtering stage.
4. If the packet has a VLAN header, it did not match step 2, and it matches an enabled host VLAN
filter, the packet is forwarded to the next filtering stage.
5. Otherwise, the packet is dropped.
The 82598 provides exact VLAN filtering for VLAN tags for host traffic and VLAN tags for manageability
traffic. See VLAN Filter Table Array – VFTA (0x0A000-0x0A9FC; RW) for detailed information on
programming VLAN filters.
The BMC configures the 82598 with eight different manageability VIDs via the Management VLAN TAG
Value [7:0] – MAVTV[7:0] registers and enables each filter in the MFVAL register.
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