F-Tile Ethernet Intel® FPGA Hard IP User Guide

ID 683023
Date 10/04/2021
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

4.4.10. Routing Delay Adjustment for Advanced Timestamp Accuracy Mode

In hardware, the existing fabric routing delays can impact the accuracy by a few hundred picoseconds. Follow the steps below to generate the routing delay information and apply the delay information to the TX/RX TAM adjust calculations described in the PTP TX/RX Client Flow sections.
For hardware run with Timestamp accuracy mode set to Advanced, use the eth_f_ptp_report_dl_path_delay.tcl script to generate the routing delay information.
  1. Copy <generated HDL directory>/ex_<speed>/eth_f_<version>/synth/eth_f_ptp_report_dl_path_delay.tcl to your Intel® Quartus® Prime software <proj dir> folder.
  2. Run full compilation.
  3. In your <proj dir> folder, run the following command:
    quartus_sta -t eth_f_ptp_report_dl_path_delay.tcl <project_name>
  4. The generated TX and RX routing delay adjustment information is available in these views:
    • In the Command Prompt window:
      Info: PTP DL Path Routing delay adjustment summary:
      Info: Average TX Routing delay adjustment for IP_INST[0].hw_ip_top|dut|eth_f_0 lane[0] = 0.702833333 ns
      Info: Average TX Routing delay adjustment for IP_INST[0].hw_ip_top|dut|eth_f_0 lane[1] = 0.8525 ns
      Info: Average RX Routing delay adjustment for IP_INST[0].hw_ip_top|dut|eth_f_0 lane[0] = 0.730833333 ns
      Info: Average RX Routing delay adjustment for IP_INST[0].hw_ip_top|dut|eth_f_0 lane[1] = 0.803 ns
      Info (23030): Evaluation of Tcl script eth_f_ptp_report_dl_path_delay.tcl was successful
    • In the generated ptp_hw_adv_adj.tcl script:
      #Average Routing Delay Adjustment (ns)
      #IPO: IP_INST[0] hw_ip_top|dut|eth_f_0
      set IPO_TX0_ROUTING_ADJ 0x846166666667
      set IPO_TX1_ROUTING_ADJ 0.70025
      set IPO_RX0_ROUTING_ADJ 0.665416666667
      set IPO_RX1_ROUTING_ADJ 0.681833333333
    • In ptp_hw_adv_adj.csv file:

  5. Use the generated routing delay values in the tx/rx_tam_adjust calculation specified in PTP TX Client Flow and PTP RX Client Flow.
    Note: If you modify your project and rerun the compilation, you also must regenerate the routing delay information by following the steps above.