Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs

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ID 813663
Date 9/01/2025
Public
Document Table of Contents
Document Table of Contents x
1. Low Latency Ethernet 10G MAC IP Overview 2. Getting Started 3. Functional Description 4. Parameter Settings for the Low Latency Ethernet 10G MAC IP Core 5. Interface Signals 6. Configuration Registers 7. Debug Checklist 8. Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs Archives 9. Document Revision History for the Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs
1. Low Latency Ethernet 10G MAC IP Overview x
1.1. Features 1.2. Release Information 1.3. Low Latency Ethernet 10G MAC Operating Modes 1.4. Device Family Support 1.5. Performance and Resource Utilization
1.5. Performance and Resource Utilization x
1.5.1. Resource Utilization 1.5.2. TX and RX Latency
2. Getting Started x
2.1. Introduction to Altera IP Cores 2.2. Installing and Licensing IP Cores 2.3. Specifying the IP Parameters and Options ( Quartus® Prime Pro Edition) 2.4. Generated File Structure 2.5. Simulating IP Cores 2.6. Upgrading the Low Latency Ethernet 10G MAC IP Core 2.7. Low Latency Ethernet 10G MAC IP Design Examples
2.6. Upgrading the Low Latency Ethernet 10G MAC IP Core x
2.6.1. Design Considerations
2.6.1. Design Considerations x
2.6.1.1. Timing Constraints
2.6.1.1. Timing Constraints x
2.6.1.1.1. Pseudo-Static CSR Fields 2.6.1.1.2. Clock Crosser 2.6.1.1.3. Dual Clock FIFO
2.7. Low Latency Ethernet 10G MAC IP Design Examples x
2.7.1. Low Latency Ethernet 10G MAC IP Design Example for Agilex™ 3 and Agilex™ 5 Devices
3. Functional Description x
3.1. Architecture 3.2. Interfaces 3.3. Frame Types 3.4. TX Datapath 3.5. RX Datapath 3.6. Flow Control 3.7. Reset Requirements 3.8. XGMII Error Handling (Link Fault) 3.9. IEEE 1588v2
3.4. TX Datapath x
3.4.1. Padding Bytes Insertion 3.4.2. Address Insertion 3.4.3. CRC-32 Insertion 3.4.4. XGMII Encapsulation 3.4.5. Inter-Packet Gap Generation and Insertion 3.4.6. XGMII Transmission 3.4.7. Unidirectional Feature 3.4.8. TX Promiscuous (Transparent) Mode 3.4.9. TX Timing Diagrams
3.5. RX Datapath x
3.5.1. XGMII Decapsulation 3.5.2. CRC Checking 3.5.3. Address Checking 3.5.4. Frame Type Checking 3.5.5. Length Checking 3.5.6. CRC and Padding Bytes Removal 3.5.7. Overflow Handling 3.5.8. RX Promiscuous (Transparent) Mode 3.5.9. RX Timing Diagrams
3.5.5. Length Checking x
3.5.5.1. Frame Length 3.5.5.2. Payload Length
3.6. Flow Control x
3.6.1. IEEE 802.3 Flow Control 3.6.2. Priority-Based Flow Control
3.6.1. IEEE 802.3 Flow Control x
3.6.1.1. Pause Frame Reception 3.6.1.2. Pause Frame Transmission
3.6.2. Priority-Based Flow Control x
3.6.2.1. PFC Frame Reception 3.6.2.2. PFC Frame Transmission
3.9. IEEE 1588v2 x
3.9.1. Architecture 3.9.2. TX Datapath 3.9.3. RX Datapath 3.9.4. Frame Format
3.9.4. Frame Format x
3.9.4.1. PTP Packet in IEEE 802.3 3.9.4.2. PTP Packet over UDP/IPv4 3.9.4.3. PTP Packet over UDP/IPv6
5. Interface Signals x
5.1. Clock and Reset Signals 5.2. Speed Selection Signal 5.3. Error Correction Signals 5.4. Unidirectional Signals 5.5. Avalon® Memory-Mapped Interface Programming Signals 5.6. Avalon® Streaming Data Interfaces 5.7. Avalon® Streaming Flow Control Signals 5.8. Avalon® Streaming Status Interface 5.9. PHY-side Interfaces 5.10. IEEE 1588v2 Interfaces
5.6. Avalon® Streaming Data Interfaces x
5.6.1. Avalon® Streaming TX Data Interface Signals 5.6.2. Avalon® Streaming RX Data Interface Signals 5.6.3. Avalon® Streaming Data Interface Clocks
5.8. Avalon® Streaming Status Interface x
5.8.1. Avalon® Streaming Interface TX Status Signals 5.8.2. Avalon® Streaming Interface RX Status Signals
5.9. PHY-side Interfaces x
5.9.1. XGMII TX Signals 5.9.2. XGMII RX Signals 5.9.3. GMII TX Signals 5.9.4. GMII RX Signals 5.9.5. MII TX Signals 5.9.6. MII RX Signals
5.10. IEEE 1588v2 Interfaces x
5.10.1. IEEE 1588v2 Egress TX Signals 5.10.2. IEEE 1588v2 Ingress RX Signals 5.10.3. IEEE 1588v2 Interface Clocks
6. Configuration Registers x
6.1. Register Map 6.2. Register Access Definition 6.3. Primary MAC Address 6.4. MAC Reset Control Register 6.5. TX Configuration and Status Registers 6.6. Flow Control Registers 6.7. Unidirectional Control Registers 6.8. RX Configuration and Status Registers 6.9. ECC Registers 6.10. Statistics Registers 6.11. Timestamp Registers
6.11. Timestamp Registers x
6.11.1. Calculating PHY Total Latency 6.11.2. Calculating Deterministic Latency 6.11.3. PTP Register Configuration
7. Debug Checklist x
7.1. Pre-Debugging Process 7.2. Clock Frequency 7.3. Recommended Reset Handling 7.4. Recommended Signals for Signal Tap
1. Low Latency Ethernet 10G MAC IP Overview
2. Getting Started
3. Functional Description
4. Parameter Settings for the Low Latency Ethernet 10G MAC IP Core
5. Interface Signals
6. Configuration Registers
7. Debug Checklist
8. Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs Archives
9. Document Revision History for the Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs

3.6.2. Priority-Based Flow Control

Follow these steps to use the priority-based flow control (PFC):

  1. Turn on the Priority-based flow control (PFC) parameter and specify the number of priority levels using the Number of PFC priorities parameter. You can specify between 2 to 8 PFC priority levels.
  2. Set the following registers.
    • On the TX datapath:
      • Set tx_pauseframe_enable to 0 to disable the IEEE 802.3 flow control.
      • Set tx_pfc_priority_enable[n] to 1 to enable the PFC for priority queue n.
    • On the RX datapath:
      • Set the IGNORE_PAUSE bit in the rx_frame_control register to 1 to disable the IEEE 802.3 flow control.
      • Set the rx_pfc_control[7:0] register bits to 0 to enable the PFC. Most of the rest of the bits are unused.
  3. Connect the avalon_st_tx_pfc_gen_data signal to the corresponding RX client logic and the avalon_st_rx_pfc_pause_data signal to the corresponding TX client logic.
  4. You have the option to configure the MAC RX to forward the PFC frame to the client by setting the rx_pfc_control[16] register to 1. By default, the MAC RX drops the PFC frame after processing it.
You must handle the XON/XOFF requests in the following manner:
  1. Assert the XOFF, which runs at the clock frequency of 312.5 MHz, for at least 1 clock cycle, which runs at the clock frequency of 312.5 MHz to ensure that the PFC frame can transfer successfully.
  2. Assert the XON, which runs at the clock frequency of 312.5 MHz, for at least 25 clock cycle to ensure that the PFC frame can transfer successfully.

Section Content
PFC Frame Reception
PFC Frame Transmission

Level Two Title