Found some more erratas concerning the PTP timer.
Depending on the selected clock - you need a delay between issue "capture" in this register - and reading HW_ENET_MAC_ATIME.
A delay from 2-3 clock cycles (as selected) is needed.
Without proper delay, read out ATIME gives corrupted values.
IRQs/event concurrency issue:
Having multiple ATIME IRQs sources (capture pps, 1ms tick, 250us periodic), firing around "0" of the interval - we observed that
comparator firing near "0" hangs up.
Running at 40Mhz with an increment of 25ns - we see that comparator events <25ns with a concurrent capture irq pending are stalled.
Workaround -> avoid comparator values < clockrate and raceconditions with simultaneous capture.