MIPS: Tidy EntryLo bit definitions, add PFN

Tidy up the definition of the EntryLo RI & XI bits using BITS_PER_LONG
rather than #ifdef'ing on CONFIG_64BIT, and add a definition for the
offset to the PFN field for use by a later patch.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11217/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/mipsregs.h

@@ -132,15 +132,9 @@
 #define R3K_ENTRYLO_N		(_ULCAST_(1) << 11)
 
 /* MIPS32/64 EntryLo bit definitions */
-#ifdef CONFIG_64BIT
-/* as read by dmfc0 */
-#define MIPS_ENTRYLO_XI		(_ULCAST_(1) << 62)
-#define MIPS_ENTRYLO_RI		(_ULCAST_(1) << 63)
-#else
-/* as read by mfc0 */
-#define MIPS_ENTRYLO_XI		(_ULCAST_(1) << 30)
-#define MIPS_ENTRYLO_RI		(_ULCAST_(1) << 31)
-#endif
+#define MIPS_ENTRYLO_PFN_SHIFT	6
+#define MIPS_ENTRYLO_XI		(_ULCAST_(1) << (BITS_PER_LONG - 2))
+#define MIPS_ENTRYLO_RI		(_ULCAST_(1) << (BITS_PER_LONG - 1))
 
 /*
  * Values for PageMask register