F-Tile Ethernet Intel® FPGA Hard IP User Guide

ID 683023
Date 10/04/2021
Public

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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.