The Ethernet Statistics User Guide (UG170 January 18, 2006) describes how to connect the 1-Gigabit Ethernet MAC Core to the Statistics Core on pages 63-64. This user guide is available to register users of the Ethernet Statistics Lounge:
There is a paragraph which states the following:
The 1-Gigabit Ethernet MAC Core already contains its own optional statistics block which provides an equivalent to counters 0 through to 33 as provided in the example design for the Ethernet Statistics Core.
This is no longer the case for v7.0 of the GEMAC Core. In v7.0 the Statistics gathering option was removed. (Versions 1.0 to 6.0 of the 1-Gig MAC did have their own statistics block).