Linux/AM3354: how to set my-own mac address?

Part Number:AM3354

Tool/software: Linux

Hi,

I'm using ti-processor-sdk-linux-rt-am335x-evm-04.03.00.05.

I don't know whether it's appropriate to ask this issue on this site. But I want some advice from Linux experts.
ASIX USB-to-Ether bridge is on my board. I want to set my-own MAC address to ASIX device permanently.
How to do this correctly?

1. Write MAC address to /etc/network/interfaces
2. u-boot env parameter(eth2addr?)
3. and more other method

I tried to write MAC address to /etc/network/interfaces. But not working... My description is below:

auto eth2
iface eth2 inet static
        address 192.168.3.100
        netmask 255.255.255.0
        hwaddress ether xx:xx:xx:xx:xx:xx

Thanks in advance.
Nishihashi