two tse_mac for DE2-115

Hi all,

I use a DE2-115 from terasic which has two ethernet ports and I want to use them simultaneously. My question is

If I use ONE CPU, TWO TSE_MAC in the sopc design, for instance, tse_mac0 and tse_mac1, how should I choose which port I will be using in the Nios simple socket server template? (In system.h, there are configurations for tse_mac0 and tse_mac1 both, but it it turns out that I can only make port0 work)

Or should I make two cpu for this kind of design?

P.S My data go directly from the physical layer, so the nios is only used to intialize the chip.