Low Latency 100-Gbps Ethernet IP Core User Guide

ID 683160
Date 4/15/2021
Public
Document Table of Contents

2.4. IP Core Parameters

The LL 100GbE parameter editor provides the parameters you can set to configure the LL 100GbE IP core and simulation and hardware design examples.

LL 100GbE IP core variations that target an Arria 10 device include an Example Design tab. For information about that tab, refer to the Low Latency 100G Ethernet Design Example User Guide.

Table 10.   LL 100GbE Parameters: Main TabDescribes the parameters for customizing the LL 100GbE IP core on the Main tab of the LL 100GbE parameter editor.

Parameter

Type

Range

Default Setting

Parameter Description

General Options
Device family

String

  • Stratix V
  • Arria 10

According to the setting in the project or IP Catalog settings.

Selects the device family.

Data interface

String

  • Custom–ST
  • Avalon–ST
Avalon–ST

Selects the Avalon® streaming interface or the narrower, custom streaming client interface to the MAC.

If you select the custom streaming client interface, the Flow control mode and Enable 1588 PTP parameters are not available.

PCS/PMA Options

Enable CAUI4 PCS

Boolean

  • True
  • False
False

If this parameter is turned on, the IP core is a 100GbE CAUI-4 variation, with four 25.78125 Gbps transceiver PHY links. If this parameter is turned off, the IP core is configured with the regular 100 Gbps PHY link option of 10 x 10.3125 Gbps.

This parameter is available only in variations that target an Arria 10 device.

Enable RS-FEC for CAUI4

Boolean

  • True
  • False
False If this parameter is turned on, the IP core implements Reed-Solomon forward error correction (FEC).

This parameter is available only in CAUI-4 variations. CAUI-4 variations must target an Arria 10 device.

Enable SyncE

Boolean

  • True
  • False

False

Exposes the RX recovered clock as an output signal. This feature supports the Synchronous Ethernet standard described in the ITU-T G.8261, G.8262, and G.8264 recommendations.

This parameter is available only in variations that target an Arria 10 device.

PHY reference frequency

Integer (encoding)

  • 322.265625 MHz
  • 644.53125 MHz

644.53125 MHz

Sets the expected incoming PHY clk_ref reference frequency. The input clock frequency must match the frequency you specify for this parameter (± 100ppm).

Use external TX MAC PLL Boolean
  • True
  • False
False If you turn this option on, the IP core is configured to expect an input clock to drive the TX MAC. The input clock signal is clk_txmac_in.

Flow Control Options

Flow control mode

String

  • No flow control
  • Standard flow control
  • Priority-based flow control

No flow control

Configures the flow control mechanism the IP core implements. Standard flow control is Ethernet standard flow control.

If you select the custom streaming client interface, the IP core must be configured with no flow control, and this parameter is not available.

Number of PFC queues

Integer

1–8

8

Number of distinct priority queues for priority-based flow control. This parameter is available only if you set Flow control mode to Priority-based flow control.

Average interpacket gap

String

  • Disable deficit idle counter
  • 8
  • 12

12

If you set the value of this parameter to 8 or to 12, the IP core includes a deficit idle counter (DIC), which maintains an average interpacket gap (IPG) of 8 or 12, as you specify. If you set the value of this parameter to Disable deficit idle counter, the IP core is configured without the DIC, and does not maintain the required minimum average IPG. The Ethernet standard requires a minimum average IPG of 12. Turning off the DIC increases bandwidth.

MAC Options

Enable 1588 PTP

Boolean

  • True
  • False

False

If turned on, the IP core supports the IEEE Standard 1588-2008 Precision Clock Synchronization Protocol, by providing the hooks to implement the Precise Timing Protocol (PTP).

If you select the custom streaming client interface, the IP core must be configured without 1588 support, and this parameter is not available.

Enable 96b Time of Day Format Boolean
  • True
  • False
True Include the 96-bit interface to the TOD module. If you turn on this parameter, the TOD module that is generated with the IP core has a matching 96-bit timestamp interface.

If Enable 1588 PTP is turned on, you must turn on at least one of Enable 96b Time of Day Format and Enable 64b Time of Day Format. You can turn on both Enable 96b Time of Day Format and Enable 64b Time of Day Format to generate a TOD interface for each format.

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

Enable 64b Time of Day Format Boolean
  • True
  • False
False Include the 64-bit interface to the TOD module. If you turn on this parameter, the TOD module that is generated with the IP core has a matching 64-bit timestamp interface.

If Enable 1588 PTP is turned on, you must turn on at least one of Enable 96b Time of Day Format and Enable 64b Time of Day Format. You can turn on both Enable 96b Time of Day Format and Enable 64b Time of Day Format to generate a TOD interface for each format.

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

Timestamp fingerprint width Integer 1–16 1 Specifies the number of bits in the fingerprint that the IP core handles.

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

Enable link fault generation

Boolean

  • True
  • False

False

If turned on, the IP core includes the link fault signaling modules and relevant signals. If turned off, the IP core is configured without these modules and without these signals. Turning on link fault signaling provides your design a tool to improve reliability, but increases resource utilization.

Enable TX CRC insertion

Boolean

  • True
  • False

True

If turned on, the IP core inserts a 32-bit Frame Check Sequence (FCS), which is a CRC-32 checksum, in outgoing Ethernet frames. If turned off, the IP core does not insert the CRC-32 sequence in outgoing Ethernet communication. Turning on TX CRC insertion improves reliability but increases resource utilization and latency through the IP core.

If you turn on flow control, the IP core must be configured with TX CRC insertion, and this parameter is not available.

Enable preamble passthrough

Boolean

  • True
  • False

False

If turned on, 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 SFD to the client instead of stripping them out of the Ethernet packet. In TX preamble pass-through mode, the client specifies the preamble to be sent in the Ethernet frame.

Enable alignment EOP on FCS word

Boolean

  • True
  • False

True

If turned on, the IP core aligns the 32-bit Frame Check Sequence (FCS) error signal with the assertion of the EOP by delaying the RX data bus to match the latency of the FCS computation. If turned off, the IP core does not delay the RX data bus to match the latency of the FCS computation. If the parameter is turned off, the FCS error signal, in the case of an FCS error, is asserted in a later clock cycle than the relevant assertion of the EOP signal.

Intel recommends that you turn on this option. Otherwise, the latency between the EOP indication and assertion of the FCS error signal is non-deterministic.

You must turn on this parameter if your design relies on the rx_inc_octetsOK signal..

Enable TX statistics

Boolean

  • True
  • False

True

If turned on, the IP core includes built–in TX statistics counters. If turned off, the IP core is configured without TX statistics counters. In any case, the IP core is configured with TX statistics counter increment output vectors.

Enable RX statistics

Boolean

  • True
  • False

True

If turned on, the IP core includes built–in RX statistics counters. If turned off, the IP core is configured without RX statistics counters. In any case, the IP core is configured with RX statistics counter increment output vectors.

Configuration, Debug and Extension Options

Enable Native PHY Debug Master Endpoint (NPDME)

Boolean

  • True
  • False

False

If turned on, the IP core turns on the following features in the Arria 10 PHY IP core that is included in the LL 100GbE IP core:

  • Enable Native PHY Debug Master Endpoint (NPDME)
  • Enable capability registers

If turned off, the IP core is configured without these features.

This parameter is available only in variations that target an Arria 10 device. For information about these Arria 10 features, refer to the Arria 10 Transceiver PHY User Guide.

Table 11.   LL 100GbE PHY Parameter SettingsLists the PHY parameters that are configured automatically based on parameter values you select in the LL 100GbE parameter editor.

Parameter

LL 100GbE Standard Variations

LL 100GbE CAUI–4 Variations (Arria 10 Devices)

Lanes

10

4

Data rate per lane

10312.5 Mbps

25781.25 Mbps

Available PHY reference clock frequencies

322.265625 MHz

644.53125 MHz

322.265625 MHz

644.53125 MHz