We have a project where after some unknown event happens, the FEC stops triggering the RXF interrupt. It could be minutes, could be days before the event happens. Wiresharking hasn't shown anything suspicious. Tx is still working, in fact, our clue that there is a problem is that the device is refreshing its ARP table on its 20 minute boundary but doesn't listen to the response.
Things I've checked when this occurs:
EBERR is 0
RXF is 0
RXB is usually 1, but that mask is not set
ETHR_EN is 1
RDAR is 1
Also, not every device seems to do this. Out of 100 devices probably 5-10 exhibit this behavior.
Any help in how to trouble shoot this would be great.