25G Ethernet Intel® Stratix® 10 FPGA IP User Guide

ID 683154
Date 9/15/2021
Public
Document Table of Contents

3. 25G Ethernet Intel FPGA IP Parameters

The 25G Ethernet Intel FPGA IP parameter editor provides the parameters you can set to configure the 25G Ethernet Intel FPGA IP core and design example.

The 25G Ethernet Intel FPGA IP parameter editor includes an Example Design tab. For information about that tab, refer to the 25G Ethernet Intel® Stratix® 10 FPGA IP Design Example User Guide.

Table 13.  IP Core Parameters
Parameter Range Default Setting Description
General Options
Device Family Stratix 10 Stratix 10 Selects the device family.
Ready Latency 0, 3 0

Selects the readyLatency value on the TX client interface. readyLatency is an Avalon® streaming interface property that defines the number of clock cycles of delay from when the IP core asserts the l1_tx_ready signal to the clock cycle in which the IP core can accept data on the TX client interface. Refer to the Avalon® Interface Specifications.

Selecting a latency of 3 eases timing closure at the expense of increased latency for the datapath.

If you set the readyLatency to 3 and turn on standard flow control, data might be delayed in the IP core while the IP core is backpressured.

Core Variant MAC+PCS+PMA, MAC+PCS MAC+PCS+PMA Selects the primary blocks to include in the IP core variation.
  • MAC+PCS+PMA—When enabled, the IP core generates with capability of MAC, PCS, and PMA protocol layers.
  • MAC+PCS—When enabled, the IP core generates with the capability of MAC and PCS only.
PCS/PMA Options
Enable RS-FEC Enabled, Disabled Disabled When enabled, the IP core implements Reed-Solomon forward error correction (FEC).
Flow Control Options
Enable flow control Enabled, Disabled Disabled When enabled, the IP core implements flow control. When either link partner experiences congestion, the respective transmit control sends pause frames. Register settings in Table 28 and Table 29 control flow control behavior, including whether the IP core implements standard flow control or priority-based flow control.

If you turn on standard flow control and set the readyLatency to 3, data might be delayed in the IP core while the IP core is backpressured.

Number of queues 1-8 8 Specifies the number of queues used in managing flow control.
MAC Options
Enable link fault generation Enabled, Disabled Disabled When enabled, the IP core implements link fault signaling as defined in the IEEE 802.3-2012 IEEE Standard for Ethernet. The MAC includes a Reconciliation Sublayer (RS) to manage local and remote faults. When enabled, the local RS TX logic can transmit remote fault sequences in case of a local fault and can transmit IDLE control words in case of a remote fault.
Enable preamble passthrough Enabled, Disabled Disabled When enabled, the IP core is in RX and TX preamble pass-through mode. In RX preamble pass-through mode, the IP core passes the preamble and Start Frame Delimiter (SFD) to the client instead of stripping them out of the Ethernet packet. In TX preamble pass-through mode, the client specifies the preamble and provides the SFD to be sent in the Ethernet frame.
Enable TX CRC passthrough Enabled, Disabled Disabled When enabled, TX MAC does not insert the CRC-32 checksum in the out-going frame. In pass-through mode, the client must provide frames with at least 64 bytes, including the Frame Check Sequence (FCS). When disabled, the TX MAC computes and inserts a 32-bit FCS in the TX MAC frame.

This parameter is not available if you turn on Enable IEEE 1588 .

Enable MAC statistics counters Enabled, Disabled Enabled When enabled, the IP core includes statistics counters that characterize TX and RX traffic.
IEEE 1588 Options
Enable IEEE 1588 Enabled, Disabled Disabled If enabled, the IP core supports the IEEE Standard 1588-2008 Precision Clock Synchronization Protocol, by providing the hooks to implement the Precise Timing Protocol (PTP).

This parameter is not available if you turn on Enable TX CRC passthrough.

Time of day format Enable 96-bit timestamp format, Enable 64-bit timestamp format, Enable both formats Enable both formats Specifies the interface to the Time of Day module. If you select Enable both formats, the IP core includes both the 64-bit interface and the 96-bit interface.

This parameter is available only in variations with Enable IEEE 1588 turned on. The IP core provides the Time of Day interface; the IP core does not include Time of Day and synchronizer modules to connect to this interface.

Fingerprint width 132 4 Specifies the number of bits in the fingerprint that the IP core handles.

This parameter is available only in variations with Enable IEEE 1588 turned on.

10G/25G Rate Switching
Enable 10G/25G dynamic rate switching Enabled, Disabled Disabled If enabled, the IP core supports dynamic reconfiguration between the 10 Gbps and the 25 Gbps data rates.
Configuration, Debug and Extension Options
Enable Native PHY Debug Master Endpoint (NPDME) Enabled, Disabled Disabled

If enabled, the Transceiver Native PHY IP includes an embedded Native PHY Debug Master Endpoint (NPDME) that connects internally to the Avalon® memory-mapped slave interface. The NPDME can access the reconfiguration space of the transceiver. It can perform certain test and debug functions via JTAG using the System Console.

Reference clock frequency 644.531250, 322.265625 644.531250 Specifies the frequency of the transceiver CDR reference clock input in MHz.
Enable auto adaptation triggering for RX PMA CTLE/DFE mode Enabled, Disabled Enabled If enabled, additional logic is instantiated to automatically request adaptation once RX data is unlocked.

If disabled, refer to Adaptation Control - Start section of the L- and H-Tile Transceiver PHY User Guide for more information about how to start adaptation.