[U-Boot] Problem with disable the datacache

Hi

I have a problem with disabling the data cache on my PPC. The target family is mpc83xx and i had tried to chance something in the start.S file for the ppc. But if i instead of the asm function dcache_enable use dcache_disable my target newer get running. So if anyone can help with informations about how to disable the data cache for a ppc it could be greath.

Kind Regards LSkov