Data Sheet

Inline Functions—Ethernet Controller I210
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•The RCTL.LPE bit is set to 1b and the packet is bigger than RLPML.RLPML bytes.
Note: Even when the RCTL.LPE bit is set, the maximum supported received-packet size is 9.5 KB
(9728 bytes).
7.1.2 Receive Queues Assignment
The following filter mechanisms determines the destination of a receive packet. These are described
briefly in this section and in full details in separate sections:
•RSS — Receive Side Scaling distributes packet processing between several processor cores by
assigning packets into different descriptor queues. RSS assigns to each received packet an RSS
index. Packets are routed to a queue out of a set of Rx queues based on their RSS index and other
considerations. See Section 7.1.2.7 for details on RSS.
• L2 Ether-type filters — These filters identify packets by their L2 Ether-type and assign them to
receive queues. Examples of possible uses are LLDP packets and 802.1X packets. See
Section 7.1.2.3 for mode details. The I210 incorporates 4 Ether-type filters.
• 2-tuple filters — These filters identify packets with specific TCP/UDP destination port and/or L4
protocol. Each filter consists of a 2-tuple (protocol and destination TCP/UDP port) and routes
packets into one of the Rx queues. The I210 has 8 such filters. See Section 7.1.2.4 for details.
• TCP SYN filters — The I210 might route TCP packets with their SYN flag set into a separate queue.
SYN packets are often used in SYN attacks to load the system with numerous requests for new
connections. By filtering such packets to a separate queue, security software can monitor and act
on SYN attacks. The I210 has one such filter. See Section 7.1.2.6 for more details.
• Flex Filters - These filters can be either used as WoL filters when the I210 is in D3 state or for
queueing in normal operating mode (D0 state). Filters enable queueing according to a match of any
128 Byte sequence at the beginning of a packet. Each one of the 128 bytes can be either compared
or masked using a dedicated mask field. The I210 has 8 such filters. See Section 7.1.2.5 for details.
• VLAN priority filters — These filters identify packets by their L2 VLAN priority and assign them to
receive queues. See Section 7.1.2.7 for mode details. The I210 incorporates 8 VLAN priority filters.
• MAC address filters — These filters identify packets by their L2 MAC address and assign them to
receive queues. See Section 7.1.2.8 for mode details. The I210 incorporates 16 MAC address
filters.
A received packet is allocated to a queue as described in the following sections.
7.1.2.1 Queuing Method
When the MRQC.Multiple Receive Queues Enable field equals 010b (multiple receive queues as defined
by filters and RSS for 4 queues) or 000b (multiple receive queues as defined by filters (2-tuple filters,
L2 Ether-type filters, SYN filter and Flex Filters), the received packet is assigned to a queue in the
following manner (Each filter identifies one of 4 receive queues):
1. Queue by MAC address filters (if a match)
2. Queue by L2 Ether-type filters (if a match)
3. If RFCTL.SYNQFP is 0b (2-tuple filter and Flex filter have priority), then:
a. Queue by Flex filter (if a match)
b. Queue by 2-tuple filter
c. Queue by SYN filter (if a match)
4. If RFCTL.SYNQFP is 1b (SYN filter has priority), then:
a. Queue by SYN filter (if a match)