Don't both systems measure time (32-bit integer) as the number of seconds since a particular epoch date?
If so, provided you know the difference between them. If memory serves, the Unix epoch is 00:00:00 Jan 01 1970 and the Amiga epoch is 00:00:00 Jan 01 1978
I would assume, if you evaluate the amiga epoch date as a unix datestamp you have a displacement you can use to convert an amiga 32-bit datestamp to a unix one and vice versa.