CONFIG_MII Must be defined if CONFIG_FEC_MXC is defined.CONFIG_FEC_XCV_TYPE Defaults to MII100 for 100 Base-tx. RGMII selects 1000 Base-tx reduced pin count interface. RMII selects 100 Base-tx reduced pin count interface.CONFIG_FEC_MXC_SWAP_PACKET Forced on iff MX28. Swaps the bytes order of all words(4 byte units) in the packet. This should not be specified by a board file. It is cpu specific.CONFIG_PHYLIB fec_mxc supports PHYLIB and should be used for new boards.CONFIG_FEC_MXC_NO_ANEG Relevant only if PHYLIB not used. Skips auto-negotiation restart.CONFIG_FEC_MXC_PHYADDR Optional, selects the exact phy address that should be connected and function fecmxc_initialize will try to initialize it.
Reading the ethaddr from the SoC eFuses:if CONFIG_FEC_MXC is defined and the U-Boot environment does not contain theethaddr variable, then its value gets read from the corresponding eFuses inthe SoC. See the README files of the specific SoC for details.