F-Tile Low Latency 100G Ethernet Intel® FPGA IP User Guide

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ID 792946
Date 12/04/2023
Public
Document Table of Contents
Document Table of Contents x
1. About the F-Tile Low Latency 100G Ethernet Intel® FPGA IP User Guide 2. About this IP 3. Getting Started 4. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Parameters 5. Functional Description 6. Reset 7. Interfaces and Signal Descriptions 8. Control, Status, and Statistics Register Descriptions 9. Document Revision History for the F-Tile Low Latency 100G Ethernet Intel® FPGA IP User Guide
2. About this IP x
2.1. Release Information 2.2. Features 2.3. Device Family Support
3. Getting Started x
3.1. Installing and Licensing Intel FPGA IP Cores 3.2. Specifying the IP Core Parameters and Options 3.3. Simulating the IP Core 3.4. Generated File Structure 3.5. Integrating Your IP Core in Your Design 3.6. Compiling the Full Design and Programming the FPGA
3.1. Installing and Licensing Intel FPGA IP Cores x
3.1.1. Intel FPGA IP Evaluation Mode
3.5. Integrating Your IP Core in Your Design x
3.5.1. Pin Assignments 3.5.2. Adding the F-Tile Reference and System PLL Clocks Intel FPGA IP 3.5.3. Placement Settings for the 100G Ethernet Intel FPGA IP Core
5. Functional Description x
5.1. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Functional Description 5.2. User Interface to Ethernet Transmission
5.1. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Functional Description x
5.1.1. F-Tile Low Latency 100G Ethernet Intel® FPGA IP TX MAC Datapath 5.1.2. 100 GbE TX PCS 5.1.3. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Core RX MAC Datapath 5.1.4. Link Fault Signaling Interface 5.1.5. 100 GbE RX PCS 5.1.6. Flow Control
5.1.1. F-Tile Low Latency 100G Ethernet Intel® FPGA IP TX MAC Datapath x
5.1.1.1. Frame Padding 5.1.1.2. Preamble Insertion 5.1.1.3. Inter-Packet Gap Generation and Insertion 5.1.1.4. Frame Check Sequence (CRC32) Insertion
5.1.3. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Core RX MAC Datapath x
5.1.3.1. IP Core Preamble Processing 5.1.3.2. IP Core Malformed Packet Handling 5.1.3.3. Length/Type Field Processing
5.1.3.3. Length/Type Field Processing x
5.1.3.3.1. Length Checking 5.1.3.3.2. RX CRC Checking and Dynamic Forwarding
5.1.6. Flow Control x
5.1.6.1. TX Pause/PFC Flow Control Frame Transmission Request 5.1.6.2. XON/XOFF Pause Frames
5.2. User Interface to Ethernet Transmission x
5.2.1. Order of Transmission 5.2.2. Bit Order For TX and RX Datapaths
7. Interfaces and Signal Descriptions x
7.1. TX MAC Interface to User Logic 7.2. RX MAC Interface to User Logic 7.3. Transceivers 7.4. Transceiver Reconfiguration Signals 7.5. Avalon Memory-Mapped Management Interface 7.6. Miscellaneous Status and Debug Signals 7.7. Flow Control Signals 7.8. Clock Signals 7.9. Reset Signals
8. Control, Status, and Statistics Register Descriptions x
8.1. TX MAC Registers 8.2. RX MAC Registers 8.3. Pause/PFC Flow Control Registers 8.4. Statistics Registers 8.5. Hard IP Registers
8.4. Statistics Registers x
8.4.1. Statistics Registers
1. About the F-Tile Low Latency 100G Ethernet Intel® FPGA IP User Guide
2. About this IP
3. Getting Started
4. F-Tile Low Latency 100G Ethernet Intel® FPGA IP Parameters
5. Functional Description
6. Reset
7. Interfaces and Signal Descriptions
8. Control, Status, and Statistics Register Descriptions
9. Document Revision History for the F-Tile Low Latency 100G Ethernet Intel® FPGA IP User Guide

8.4. Statistics Registers

The 100G Ethernet Intel FPGA IP statistics registers count Ethernet traffic and errors. The 64-bit statistics registers are designed to roll over, to ensure timing closure on the FPGA. However, these registers should never roll over if the link is functioning properly. The statistics registers check the size of frames, which includes the following fields:

  • Size of the destination address
  • Size of the source address
  • Size of the data
  • Four bytes of CRC

The statistics counters module is a synthesis option. The statistics registers are counters that are implemented inside the CSR. When you turn on the Enable MAC statistics counters parameter in the 100G Ethernet Intel FPGA IP parameter editor, the counters are implemented in the CSR. When you turn off the Enable MAC statistics counters parameter in the 100G Ethernet Intel FPGA IP parameter editor, the counters are not implemented in the CSR, and read access to the counters returns undefined results.

After system power-up, the statistics counters have random values. You must clear these registers and confirm the system is stable before using their values. To clear the registers, use any of the following methods:

  1. Assert csr_rst_n to clear both the TX and RX statistic counters.
  2. Assert i_tx_rst_n to clear the TX statistic counters.
  3. Assert i_rx_rst_n to clear the RX statistic counters.
  4. Write 1'b1 to bit[0] of the CNTR_TX_CONFIG (0x845) to clear the TX statistic counters.
  5. Write 1'b1 to bit[0] of the CNTR_RX_CONFIG (0x945) to clear the RX statistic counters.

The configuration register at offset 0x845 allows you to clear all TX statistics counters. The configuration register at offset 0x945 allows you to clear all RX statistics counters. If you exclude these registers, you can monitor the statistics counter increment vectors that the IP core provides at the client side interface and maintain your own counters.

Reading the value of a statistics register does not affect its value.

To ensure that the counters you read are consistent, you should issue a shadow request to create a snapshot of all TX or RX statistics registers, by setting bit [2] of the configuration register at offset 0x845 or 0x945, respectively. Until you reset this bit, the counters continue to increment but the readable values remain constant. You can read bit [1] of the status register at offset 0x846 or 0x946, respectively, to confirm your shadow request has been granted or released.


Section Content
Statistics Registers

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