Description
Due to a design problem with the HPS EMAC 1 and HPS EMAC 2, the timestamp data output signals will not show data when enabling the Precision Time Protocol(PTP). This happens when using the Intel® Quartus® Prime Pro Edition Software version 17.1 and later, the behavior will occur as follows:
- HPS EMAC1 timestamp data output (a10_hps_emac1_ptp_tstmp_data) shows up on HPS EMAC2 timestamp data output signal (a10_hps_emac2_ptp_tstmp_data).
- HPS EMAC2 timestamp data output (a10_hps_emac2_ptp_tstmp_data) shows up on HPS EMAC1 timestamp data output signal (a10_hps_emac1_ptp_tstmp_data).
- HPS EMAC0 is not affected.
Resolution
To work around this problem:
- When enabling EMAC1 in the system, whether connected to the HPS IO or to the FPGA, and you want to use PTP timestamp data for EMAC1 in the FPGA fabric, you must enable EMAC2 PTP FPGA Interface and export and use the HPS EMAC2 timestamp data output signal (a10_hps_emac2_ptp_tstmp_data) within the fabric, to get the true timestamp data associated with EMAC1.
- When enabling EMAC2 in the system, whether connected to the HPS IO or to the FPGA, and you want to use PTP timestamp data for EMAC2 in the FPGA fabric, you must enable EMAC1 PTP FPGA Interface and export and use the HPS EMAC1 timestamp data output signal (a10_hps_emac1_ptp_tstmp_data) within the fabric, to get the true timestamp data associated with EMAC2.