[Linuxptp-users] Question about hardware receive filter mode

[Ledda W. E. <Wil...@it...>]

Hi all,
I was querying timestamp capabilities of an interface with ethtool -T and I found the following

Hardware Receive Filter Modes:
                none                  (HWTSTAMP_FILTER_NONE)
                all                   (HWTSTAMP_FILTER_ALL)
                ptpv1-l4-sync         (HWTSTAMP_FILTER_PTP_V1_L4_SYNC)
                ptpv1-l4-delay-req    (HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ)
                ptpv2-l4-sync         (HWTSTAMP_FILTER_PTP_V2_L4_SYNC)
                ptpv2-l4-delay-req    (HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ)
                ptpv2-l2-sync         (HWTSTAMP_FILTER_PTP_V2_L2_SYNC)
                ptpv2-l2-delay-req    (HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ)
                ptpv2-event           (HWTSTAMP_FILTER_PTP_V2_EVENT)
                ptpv2-sync            (HWTSTAMP_FILTER_PTP_V2_SYNC)
                ptpv2-delay-req       (HWTSTAMP_FILTER_PTP_V2_DELAY_REQ)


I'm curios to understand the meaning of the different filters in particular those related to PTP. Can I found some benefit from  them? I mean... if an interface with those filter is "better" than one that doesn't has them?

Thank you

William