Hi

I have to admit, that I don't know right now, where this big endian/little endian change is made. Perhaps some boot-strapping pin? Not sure, would have to look in the manual. Martijn? Could you jump in here?

first lines in cpu/ixp/start.S reset: /* disable mmu, set big-endian */

For the 2 IXP4xx boards I used (ixdpg425 and pdnb3) I can say, that they "just work" with the current U-Boot implementation in big endian mode. And here

The NPEs won't work when the cpu is run in little endian mode, according to the datasheet.

best regards, Martijn de Gouw