powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M

Add the ability for a classic ppc kernel to be loaded at an address
of 32MB.  This done by fixing a few places that assume we are loaded
at address 0, and by changing several uses of KERNELBASE to use
PAGE_OFFSET, instead.

Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index 578294c..666a5e8 100644
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -48,7 +48,7 @@
 
 #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
 /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
-#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
+#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET))
 #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
 #endif
 #endif
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index cd56097..8cba46f 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -269,7 +269,7 @@
 }
 
 /*
- * Map in a big chunk of physical memory starting at KERNELBASE.
+ * Map in a big chunk of physical memory starting at PAGE_OFFSET.
  */
 void __init mapin_ram(void)
 {
@@ -278,7 +278,7 @@
 	int ktext;
 
 	s = mmu_mapin_ram();
-	v = KERNELBASE + s;
+	v = PAGE_OFFSET + s;
 	p = memstart_addr + s;
 	for (; s < total_lowmem; s += PAGE_SIZE) {
 		ktext = ((char *) v >= _stext && (char *) v < etext);
diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index 9d97db7..45d9253 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -95,16 +95,16 @@
 			break;
 	}
 
-	setbat(2, KERNELBASE, 0, bl, _PAGE_RAM);
-	done = (unsigned long)bat_addrs[2].limit - KERNELBASE + 1;
+	setbat(2, PAGE_OFFSET, 0, bl, _PAGE_RAM);
+	done = (unsigned long)bat_addrs[2].limit - PAGE_OFFSET + 1;
 	if ((done < tot) && !bat_addrs[3].limit) {
 		/* use BAT3 to cover a bit more */
 		tot -= done;
 		for (bl = 128<<10; bl < max_size; bl <<= 1)
 			if (bl * 2 > tot)
 				break;
-		setbat(3, KERNELBASE+done, done, bl, _PAGE_RAM);
-		done = (unsigned long)bat_addrs[3].limit - KERNELBASE + 1;
+		setbat(3, PAGE_OFFSET+done, done, bl, _PAGE_RAM);
+		done = (unsigned long)bat_addrs[3].limit - PAGE_OFFSET + 1;
 	}
 
 	return done;