sh: Try PMB mapping based on physical address, not mapping size

We should favour PMB mappings when the physical address cannot be
reached with 29-bits.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/ioremap_32.c b/arch/sh/mm/ioremap_32.c
index c325061..a86eaa9 100644
--- a/arch/sh/mm/ioremap_32.c
+++ b/arch/sh/mm/ioremap_32.c
@@ -83,7 +83,7 @@
 	 *
 	 * PMB entries are all pre-faulted.
 	 */
-	if (unlikely(size >= 0x1000000)) {
+	if (unlikely(phys_addr >= P1SEG)) {
 		unsigned long mapped = pmb_remap(addr, phys_addr, size, flags);
 
 		if (likely(mapped)) {