Physical Memory map holes in PPC

Benjamin Herrenschmidt benh at
Fri Apr 23 16:31:30 EST 2004

> I have looked through the boot memory allocator code for PPC and I dont find
> a similar memory map. They use a phys_avail array for boot memory allocation
> which is initialized to a single region from PPC_MEMSTART to total_memory.
> >From this it appears that there are no "holes" in physical memory map for
> PPC.

Most ppc32 don't, though it's fairly dependant on a given board. ppc64
do have holes, though at this point, it's not simple to get to them, the
data structure representing the physical memory map beeing marked __init...


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