REGION_SHIFT       16 arch/powerpc/include/asm/book3s/64/hash-4k.h #define REGION_SHIFT		(MAX_EA_BITS_PER_CONTEXT - 2)
REGION_SHIFT       16 arch/powerpc/include/asm/book3s/64/hash-64k.h #define REGION_SHIFT		MAX_EA_BITS_PER_CONTEXT
REGION_SHIFT       63 arch/powerpc/include/asm/nohash/64/pgtable.h #define REGION_SHIFT		60UL