Data Sheet

Inline Functions—Ethernet Controller I210
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VLAN priority filters are configured via the VLANPQF registers as follows:
• Queue En — Enables forwarding of packets for each VLAN priority to a specific queue.
• Rx Queue field — Contains the destination queue for each VLAN priority packet.
7.1.2.8 VLAN Tag Filters
The I210 can forward packets according to their VLAN tag to separate queues. The I210 supports the
configuration of the destination queue per VLAN tag.
VLAN tag filters are configured via the VLANTAGQF registers as follows:
• VLAN tag value - The VLAN tag value to be filtered
• Queue En — Enables forwarding of packets for each filtered VLAN tag to a specific queue.
• Rx Queue field — Contains the destination queue for each filtered VLAN tag packet.
7.1.2.9 MAC Address Filters
The I210 can forward packets according to their MAC address to separate queues. The I210 supports
the configuration of the destination queue per MAC address.
MAC Address filters are configured via the RAL/H registers as follows:
• MAC address value - The MAC address value to be filtered
• Queue En — Enables forwarding of packets for each filtered MAC address to a specific queue.
• Rx Queue field — Contains the destination queue for each filtered MAC address.
7.1.2.10 Receive-Side Scaling (RSS)
RSS is a mechanism to distribute received packets into several descriptor queues. Software then
assigns each queue to a different processor, sharing the load of packet processing among several
processors.
The I210 uses RSS as one ingredient in its packet assignment policy (the others are the various filters
for Qav). The RSS output is a RSS index. The I210’s global assignment uses these bits (or only some of
the LSB bits) as part of the queue number.
RSS is enabled by the MRQC register. The RSS hash is reported only on the advanced receive descriptor
and it multiplexed with UDP fragmentation parameters. Selection between these two status indications
is done by the RXCSUM.PCSD bit setting.
When RSS is enabled, the I210 provides software with the following information as required by
Microsoft* RSS specification or for device driver assistance:
• A Dword result of the Microsoft* RSS hash function, to be used by the stack for flow classification,
is written into the receive packet descriptor (required by Microsoft* RSS).
•A 4-bit RSS Type field conveys the hash function used for the specific packet (required by
Microsoft* RSS).
Figure 7-6 shows the process of computing an RSS output:
1. The receive packet is parsed into the header fields used by the hash operation (such as IP
addresses, TCP port, etc.).