Low Latency 100-Gbps Ethernet IP Core User Guide

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ID 683160
Date 4/15/2021
Public
Document Table of Contents
Document Table of Contents x
1. About the LL 100GbE IP Core 2. Getting Started 3. Functional Description 4. Debugging the Link A. Additional Information
1. About the LL 100GbE IP Core x
1.1. LL 100GbE IP Core Supported Features 1.2. IP Core Device Family and Speed Grade Support 1.3. IP Core Verification 1.4. Performance and Resource Utilization 1.5. Release Information
1.2. IP Core Device Family and Speed Grade Support x
1.2.1. LL 100GbE IP Core Device Family Support 1.2.2. LL 100GbE IP Core Device Speed Grade Support
1.3. IP Core Verification x
1.3.1. Simulation Environment 1.3.2. Compilation Checking 1.3.3. Hardware Testing
1.4. Performance and Resource Utilization x
1.4.1. Arria 10 Resource Utilization 1.4.2. Stratix V Resource Utilization
2. Getting Started x
2.1. Installation and Licensing for LL 100GbE IP Core for Stratix® V Devices 2.2. Installing and Licensing Intel® FPGA IP Cores 2.3. Specifying the IP Core Parameters and Options 2.4. IP Core Parameters 2.5. Files Generated for Stratix V Variations 2.6. Files Generated for Arria 10 Variations 2.7. Integrating Your IP Core in Your Design 2.8. IP Core Testbenches 2.9. Compiling the Full Design and Programming the FPGA 2.10. Initializing the IP Core
2.2. Installing and Licensing Intel® FPGA IP Cores x
2.2.1. Intel® FPGA IP Evaluation Mode
2.7. Integrating Your IP Core in Your Design x
2.7.1. Pin Assignments 2.7.2. External Transceiver Reconfiguration Controller Required in Stratix V Designs 2.7.3. Transceiver PLL Required in Arria 10 Designs 2.7.4. Handling Potential Jitter in Intel® Arria® 10 Devices 2.7.5. External Time-of-Day Module for Variations with 1588 PTP Feature 2.7.6. External TX MAC PLL 2.7.7. Placement Settings for the LL 100GbE Core
2.8. IP Core Testbenches x
2.8.1. Testbench Behavior 2.8.2. Simulating the LL 100GbE IP Core With the Testbenches
2.8.2. Simulating the LL 100GbE IP Core With the Testbenches x
2.8.2.1. Generating the LL 100GbE Testbench 2.8.2.2. Optimizing the IP Core Simulation With the Testbenches 2.8.2.3. Simulating with the Modelsim Simulator 2.8.2.4. Simulating with the NCSim Simulator 2.8.2.5. Simulating with the VCS Simulator 2.8.2.6. Testbench Output Example
3. Functional Description x
3.1. High Level System Overview 3.2. LL 100GbE IP Core Functional Description 3.3. Signals 3.4. Software Interface: Registers 3.5. Ethernet Glossary
3.2. LL 100GbE IP Core Functional Description x
3.2.1. LL 100GbE IP Core TX Datapath 3.2.2. LL 100GbE IP Core TX Data Bus Interfaces 3.2.3. LL 100GbE IP Core RX Datapath 3.2.4. LL 100GbE IP Core RX Data Bus Interfaces 3.2.5. Low Latency 100GbE CAUI–4 PHY 3.2.6. External Reconfiguration Controller 3.2.7. External Transceiver PLL 3.2.8. External TX MAC PLL 3.2.9. Congestion and Flow Control Using Pause Frames 3.2.10. Pause Control and Generation Interface 3.2.11. Pause Control Frame Filtering 3.2.12. Link Fault Signaling Interface 3.2.13. Statistics Counters Interface 3.2.14. 1588 Precision Time Protocol Interfaces 3.2.15. PHY Status Interface 3.2.16. Transceiver PHY Serial Data Interface 3.2.17. Control and Status Interface 3.2.18. Arria 10 Transceiver Reconfiguration Interface 3.2.19. Clocks 3.2.20. Resets
3.2.1. LL 100GbE IP Core TX Datapath x
3.2.1.1. Preamble, Start, and SFD Insertion 3.2.1.2. Address Insertion 3.2.1.3. Length/Type Field Processing 3.2.1.4. Frame Padding 3.2.1.5. Frame Check Sequence (CRC-32) Insertion 3.2.1.6. Inter-Packet Gap Generation and Insertion 3.2.1.7. TX RSFEC 3.2.1.8. Error Insertion Test and Debug Feature
3.2.2. LL 100GbE IP Core TX Data Bus Interfaces x
3.2.2.1. LL 100GbE IP Core User Interface Data Bus 3.2.2.2. LL 100GbE IP Core TX Data Bus with Adapters (Avalon-ST Interface) 3.2.2.3. LL 100GbE IP Core TX Data Bus Without Adapters (Custom Streaming Interface) 3.2.2.4. Bus Quantization Effects With Adapters 3.2.2.5. User Interface to Ethernet Transmission
3.2.2.5. User Interface to Ethernet Transmission x
3.2.2.5.1. Order of Transmission
3.2.3. LL 100GbE IP Core RX Datapath x
3.2.3.1. LL 100GbE IP Core RX Filtering 3.2.3.2. LL 100GbE IP Core Preamble Processing 3.2.3.3. LL 100GbE IP Core FCS (CRC-32) Removal 3.2.3.4. LL 100GbE IP Core CRC Checking 3.2.3.5. LL 100GbE IP Core Malformed Packet Handling 3.2.3.6. RX CRC Forwarding 3.2.3.7. Inter-Packet Gap 3.2.3.8. RX RSFEC 3.2.3.9. Pause Ignore 3.2.3.10. Control Frame Identification
3.2.4. LL 100GbE IP Core RX Data Bus Interfaces x
3.2.4.1. LL 100GbE IP Core User Interface Data Bus 3.2.4.2. LL 100GbE IP Core RX Data Bus with Adapters (Avalon-ST Interface) 3.2.4.3. LL 100GbE IP Core RX Data Bus Without Adapters (Custom Streaming Interface)
3.2.9. Congestion and Flow Control Using Pause Frames x
3.2.9.1. Conditions Triggering XOFF Frame Transmission 3.2.9.2. Conditions Triggering XON Frame Transmission
3.2.13. Statistics Counters Interface x
3.2.13.1. OctetOK Count Interface
3.2.14. 1588 Precision Time Protocol Interfaces x
3.2.14.1. Implementing a 1588 System That Includes a LL 100GbE Core 3.2.14.2. PTP Receive Functionality 3.2.14.3. PTP Transmit Functionality 3.2.14.4. External Time-of-Day Module for 1588 PTP Variations 3.2.14.5. PTP Timestamp and TOD Formats 3.2.14.6. 1588 PTP Interface Signals
3.3. Signals x
3.3.1. LL 100GbE IP Core Signals
3.4. Software Interface: Registers x
3.4.1. LL 100GbE IP Core Registers 3.4.2. LL 100GbE Hardware Design Example Registers
3.4.1. LL 100GbE IP Core Registers x
3.4.1.1. PHY Registers 3.4.1.2. Link Fault Signaling Registers 3.4.1.3. LL 100GbE IP Core MAC Configuration Registers 3.4.1.4. Pause Registers 3.4.1.5. TX Statistics Registers 3.4.1.6. RX Statistics Registers 3.4.1.7. 1588 PTP Registers 3.4.1.8. TX Reed-Solomon FEC Registers 3.4.1.9. RX Reed-Solomon FEC Registers
3.4.2. LL 100GbE Hardware Design Example Registers x
3.4.2.1. Packet Client Registers
4. Debugging the Link x
4.1. Creating a Signal Tap Debug File to Match Your Design Hierarchy
A. Additional Information x
A.1. LL 100GbE IP Core User Guide Archives A.2. LL 100GbE IP Core User Guide Revision History
1. About the LL 100GbE IP Core
2. Getting Started
3. Functional Description
4. Debugging the Link
A. Additional Information

3.2.19. Clocks

You must set the transceiver reference clock (clk_ref) frequency to a value that the IP core supports. The LL 100GbE IP core supports clk_ref frequencies of 644.53125 MHz ±100 ppm and 322.265625 MHz ± 100 ppm. The ±100ppm value is required for any clock source providing the transceiver reference clock.

Sync–E IP core variations are IP core variations for which you turn on Enable SyncE in the parameter editor. These variations provide the RX recovered clock as a top-level output signal. This option is available only for IP core variations that target an Arria 10 device.

The Synchronous Ethernet standard, described in the ITU-T G.8261, G.8262, and G.8264 recommendations, requires that the TX clock be filtered to maintain synchronization with the RX reference clock through a sequence of nodes. The expected usage is that user logic drives the TX PLL reference clock with a filtered version of the RX recovered clock signal, to ensure the receive and transmit functions remain synchronized. In this usage model, a design component outside the LL 100GbE IP core performs the filtering.

Table 27.  Clock InputsDescribes the input clocks that you must provide.

Signal Name

Description

clk_status

Clocks the control and status interface. The clock quality and pin chosen are not critical. clk_status is expected to be a 100–125 MHz clock.

reconfig_clk

Clocks the Arria 10 transceiver reconfiguration interface. The clock quality and pin chosen are not critical. reconfig_clk is expected to be a 100 MHz clock; the allowed frequency range depends on Arria 10 transceiver requirements and is not IP core specific.

clk_ref

In IP core variations that target an Arria 10 device, clk_ref is the reference clock for the transceiver RX CDR PLL. In other IP core variations, clk_ref is the reference clock for the transceiver TX PLL and the RX CDR PLL.

The frequency of this input clock must match the value you specify for PHY reference frequency in the IP core parameter editor, with a ±100 ppm accuracy per the IEEE 802.3ba-2010 High Speed Ethernet Standard..

In addition, clk_ref must meet the jitter specification of the IEEE 802.3ba-2010 High Speed Ethernet Standard.

The PLL and clock generation logic use this reference clock to derive the transceiver and PCS clocks. The input clock should be a high quality signal on the appropriate dedicated clock pin. Refer to the relevant device datasheet for transceiver reference clock phase noise specifications.

clk_txmac_in If you turn on Use external TX MAC PLL in the LL 100GbE parameter editor, this clock drives the TX MAC. The port is expected to receive the clock from the external TX MAC PLL and drives the internal clock clk_txmac. The required TX MAC clock frequency is 390.625 MHz. User logic must drive clk_txmac_in from a PLL whose input is the PHY reference clock, clk_ref.

tx_serial_clk[9:0]

tx_serial_clk[3:0] (CAUI-4)

These input clocks are present only in variations that target an Arria 10 device. They are part of the external PLL interface to these variations. Each clock targets a single transceiver PHY link. You must drive these clocks from one or more TX transceiver PLLs that you configure separately from the LL 100GbE IP core.

Table 28.  Clock OutputsDescribes the output clocks that the IP core provides. In most cases these clocks participate in internal clocking of the IP core as well.

Signal Name

Description

clk_txmac

The TX clock for the IP core is clk_txmac. The TX MAC clock frequency is 390.625 MHz.

If you turn on Use external TX MAC PLL in the LL 100GbE parameter editor, the clk_txmac_in input clock drives clk_txmac.

clk_rxmac

The RX clock for the IP core is clk_rxmac. The RX MAC clock frequency is 390.625 MHz.

This clock is only reliable when rx_pcs_ready has the value of 1. The IP core generates clk_rxmac from a recovered clock that relies on the presence of incoming RX data.

clk_rx_recover RX recovered clock. This clock is available only if you turn on Enable SyncE in the LL 100GbE parameter editor.

The RX recovered clock frequency is 322.265625 MHz in standard variations and 402.83203 MHz in CAUI-4 variations..

The expected usage is that you drive the TX transceiver PLL reference clock with a filtered version of clk_rx_recover, to ensure the receive and transmit functions remain synchronized in your Synchronous Ethernet system. To do so you must instantiate an additional component in your design. The IP core does not provide filtering.

Figure 33. Clock Generation Circuitry Provides a high-level view of the clock generation circuitry and clock distribution to the transceiver. In Arria 10 variations, the TX transceiver PLL is configured outside the LL 100GbE IP core, and clk_ref drives the RX CDR PLL. In Arria 10 variations, you can connect a separate reference clock for the external TX transceiver PLL.
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