The i.MX6 includes a 10/100/1000 Ethernet. In Linux this is the eth0 interface. The MAC address uses the Technologic Systems 00:d0:69:00:00:00, and the last 3 octets are assigned from our pool. The MAC address is burned into the CPU's fuses during production, and will be read back automatically by software in Linux or U-Boot. Each board is also assigned 1 additional sequential mac address which is used on some carrier boards that add a second ethernet.
Freescale has a published erratum regarding the maximum Ethernet speed. The default kernel can achieve about 400 Mb/s.