Hi software@newcelio.com,
I will suggest to use the lwip_tcpecho_sa, this has an example that don't use the freertos.
Also the I think you could take the functions need it for the initialization like the debug console ones and the related to the Ethernet feature from the board.h and I think all the functions refers to the chip library at some point.
Also, if you're using a different PHY you could try modifying the board files to match the commands need it fro your PHY. I think that will be easier than do it from 0.
Unfortunately, there isn't an easier way to do this.
Best Regards,
Alexis Andalon