[PATCH] ppc: Add support for bigger page sizes than 4KB on PPC44x

[Paul Mackerras]

Stefan Roese writes:

> This patch adds support for the PAGE_SIZE set equal to 64 KB on
> PPC32 platforms.

If I'm reading the patch right, with 64k pages you're using 8kB pgd
arrays and 256-byte pte arrays, so you're only using 1/256th of each
PTE page.  In fact each PTE page could map 512MB (assuming 8 byte
ptes), and the pgd array could be a tiny 8-entry thing, which we could
kmalloc.  I think that would use memory more efficiently.

Paul.