Running MMU less Linux on Cortex-R4
I'm sorry but I can't help you so much..

I had experience only with uClinux on an ARM7 NXPLCP2468 supplied with this board http://www.embeddedartists.com/products/kits/lpc2468_kit.php .

My experience is that this kind of block appear often on this kind of linux, and aren't always predictable.
I've made some test with simple calculus of mathematical function like FFT written in c and compiled with gcc, but I got so many problem, kernel panic and so on.
In conclusion, I'm switched to Linux running on an ARM9.

My suggestion is to put a lot of ram on your board and read with attention all the note about the difference between uClinux and Linux.