RADIX_PTE_FRAG_SIZE_SHIFT   16 arch/powerpc/include/asm/book3s/64/radix-4k.h #define RADIX_PTE_FRAG_SIZE_SHIFT  (RADIX_PTE_INDEX_SIZE + 3)
RADIX_PTE_FRAG_SIZE_SHIFT   17 arch/powerpc/include/asm/book3s/64/radix-64k.h #define RADIX_PTE_FRAG_SIZE_SHIFT  (RADIX_PTE_INDEX_SIZE + 3)