Data Sheet

Ethernet Controller I210 —Inline Functions
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7.1.2.2 Queue Configuration Registers
Configuration registers (CSRs) that control queue operation are replicated per queue (total of 4 copies
of each register). Each of the replicated registers correspond to a queue such that the queue index
equals the serial number of the register (such as register 0 corresponds to queue 0, etc.). Registers
included in this category are:
• RDBAL and RDBAH — Rx Descriptor Base
• RDLEN — RX Descriptor Length
• RDH — RX Descriptor Head
• RDT — RX Descriptor Tail
• RXDCTL — Receive Descriptor Control
• RXCTL — Rx DCA Control
• SRRCTL — Split and Replication Receive Control
• PSRTYPE — Packet Split Receive Type
7.1.2.3 L2 Ether-type Filters
These filters identify packets by L2 Ether-type and assign them to a receive queue. The following
usages have been identified:
• IEEE 802.1X packets — Extensible Authentication Protocol over LAN (EAPOL).
• Time sync packets (such as IEEE 1588) — Identifies Sync or Delay_Req packets
• IEEE802.1AB LLDP (Link Layer Discovery Protocol) packets.
• IEEE1722 (Layer 2 Transport Protocol for Time Sensitive Applications) packets
• IEEE1722 Layer 2 transport protocol for timed sensitive applications.
The I210 incorporates 4 Ether-type filters.
The Packet Type field in the Rx descriptor captures the filter number that matched the L2 Ether-type.
See Section 7.1.4.2 for decoding of the Packet Type field.
The Ether-type filters are configured via the ETQF register as follows:
•The EType field contains the 16-bit Ether-type compared against all L2 type fields in the Rx packet.
•The Filter Enable bit enables identification of Rx packets by Ether-type according to this filter. If this
bit is cleared, the filter is ignored for all purposes.
• The Etype Length and Etype Length Enable are used to enable parsing beyond the Ethertype
defined by the ETQF entry, the Etype Length points to the following Ethertype in the packet to
support extended Rx parsing.
•The Rx Queue field contains the absolute destination queue for the packet.
•The 1588 Time Stamp field indicates that the packet should be time stamped according to the IEEE
1588 specification.
•The Queue Enable field enables forwarding Rx packets based on the Ether-type defined in this
register. Refer to Section 7.1.2.1 on the impact and order of ETQF on the I210 queue selection
algorithm.
• The Ethertype length field contains the size of the Ethertype in bytes.
• The Ethertype length Enable field enables the parsing of the Rx packets based on the Ethertype
defined in this register.