The ingress logic does not parse the ingress packets to search for 1588
(PTP) frames. Instead, it takes a timestamp for every received frame and outputs this value
to the user logic. The feature is always enabled, but the timestamp output can be ignored if
you do not require this function. The timestamp can be extracted from the
rx_ptp_tstamp_out_<N> signal, where N corresponds to the bus
rx_ptp_tstamp_outshould be ignored for short packets.