Change the temp map to ROM to align addresses to page size.

With a page size of BOOKE_PAGESZ_16M, both the real and effective
addresses must be multiples of 16MB.  The hardware silently truncates
them so the code happens to work.  This patch clarifies the situation
by establishing addresses that the hardware doesn't need to truncate.
Signed-off-by: NAndrew Klossner <andrew@cesa.opbu.xerox.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>

cpu/mpc85xx/start.S

@@ -188,11 +188,12 @@ _start_e500:
 	lis     r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_16M)@h
 	ori     r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_16M)@l
 
-	lis     r8,FSL_BOOKE_MAS2(TEXT_BASE, (MAS2_I|MAS2_G))@h
-	ori     r8,r8,FSL_BOOKE_MAS2(TEXT_BASE, (MAS2_I|MAS2_G))@l
+	/* Align the mapping to 16MB */
+	lis     r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xff000000, (MAS2_I|MAS2_G))@h
+	ori     r8,r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xff000000, (MAS2_I|MAS2_G))@l
 
-	lis     r9,FSL_BOOKE_MAS3(0xff800000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@h
-	ori     r9,r9,FSL_BOOKE_MAS3(0xff800000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@l
+	lis     r9,FSL_BOOKE_MAS3(0xff000000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@h
+	ori     r9,r9,FSL_BOOKE_MAS3(0xff000000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@l
 
 	mtspr   MAS0,r6
 	mtspr   MAS1,r7