powerpc/mm: Split the various pgtable-* headers based on MMU type

This patch moves the definition of the PTE format for each MMU type
to separate files instead of all in one file. This improves overall
maintainability and will make it easier to add new types.

On 64-bit, additionally, I've separated the headers relative to the
format of the page table tree (3 vs. 4 levels for 64K vs 4K pages)
from the headers specific to the PTE format for hash based processors,
this will make it easier to add support for Book3 "E" 64-bit
implementations.

There are still some type-related ifdef's in the generic headers,
we might remove them in the long run, but this patch shouldn't result
in any code change, -hopefully- just definitions being moved around.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/pte-hash64.h b/arch/powerpc/include/asm/pte-hash64.h
new file mode 100644
index 0000000..6276663
--- /dev/null
+++ b/arch/powerpc/include/asm/pte-hash64.h
@@ -0,0 +1,47 @@
+#ifndef _ASM_POWERPC_PTE_HASH64_H
+#define _ASM_POWERPC_PTE_HASH64_H
+#ifdef __KERNEL__
+
+/*
+ * Common bits between 4K and 64K pages in a linux-style PTE.
+ * These match the bits in the (hardware-defined) PowerPC PTE as closely
+ * as possible. Additional bits may be defined in pgtable-hash64-*.h
+ */
+#define _PAGE_PRESENT	0x0001 /* software: pte contains a translation */
+#define _PAGE_USER	0x0002 /* matches one of the PP bits */
+#define _PAGE_FILE	0x0002 /* (!present only) software: pte holds file offset */
+#define _PAGE_EXEC	0x0004 /* No execute on POWER4 and newer (we invert) */
+#define _PAGE_GUARDED	0x0008
+#define _PAGE_COHERENT	0x0010 /* M: enforce memory coherence (SMP systems) */
+#define _PAGE_NO_CACHE	0x0020 /* I: cache inhibit */
+#define _PAGE_WRITETHRU	0x0040 /* W: cache write-through */
+#define _PAGE_DIRTY	0x0080 /* C: page changed */
+#define _PAGE_ACCESSED	0x0100 /* R: page referenced */
+#define _PAGE_RW	0x0200 /* software: user write access allowed */
+#define _PAGE_BUSY	0x0800 /* software: PTE & hash are busy */
+
+/* Strong Access Ordering */
+#define _PAGE_SAO	(_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT)
+
+#define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
+
+#define _PAGE_WRENABLE	(_PAGE_RW | _PAGE_DIRTY)
+
+/* PTEIDX nibble */
+#define _PTEIDX_SECONDARY	0x8
+#define _PTEIDX_GROUP_IX	0x7
+
+#define PAGE_PROT_BITS	(_PAGE_GUARDED | _PAGE_COHERENT | \
+			 _PAGE_NO_CACHE | _PAGE_WRITETHRU |		\
+			 _PAGE_4K_PFN | _PAGE_RW | _PAGE_USER |		\
+			 _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_EXEC)
+
+
+#ifdef CONFIG_PPC_64K_PAGES
+#include <asm/pte-hash64-64k.h>
+#else
+#include <asm/pte-hash64-4k.h>
+#endif
+
+#endif /* __KERNEL__ */
+#endif /*  _ASM_POWERPC_PTE_HASH64_H */