I dug more on the subject, and I think I found what Marvell's PHY/MAC
doesn't like.
Hi Richard
What PHY is being used?
After analyzing the ethernet frame on the Davicom PHY's output (pin
TX+), I find out that the FCS errors occurs when the ethernet preamble
is longer than 56bits. (something like 58 or 60 bits)
Some Marvell PHYs have a register bit which might be of interest: Page
2, register 16, bit 6.
0 = Pad odd nibble preambles in copper receive packets.
1 = Pass as is and do not pad odd nibble preambles in
Andrew