Description
Yes, both the 10G MAC, and 10G PCS support 16K byte frames:
With reference to the 10-Gbps Ethernet MAC MegaCore Function User Guide (PDF), note that rx_frame_maxlength is a 16bit register, so although in theory 64Kbytes is supported, in reality greater than 16Kbyte frames would cause FIFO overflow.
The theoretical max frame length for the MAC is 64Kbytes.
However the PCS (or the XAUI in this case) is only rated to support 16K frames with a clock tolerance of /-100ppm, which matches the IEEE 802.3 specification. In order for the PCS to be able to run frames up to 64Kbytes, the reference clock tolerance must be divided by 4. So the clock must be at /-25ppm.
But for 16Kbyte frames, the standard /-100ppm is fine.