---

yaml
---
r: 204472
b: refs/heads/master
c: aec9222
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5c8974538afd97990d3730ef6fea731a34ef1f85
+refs/heads/master: aec9222551353890190af810a4c93ed7050bfa19

trunk/arch/mips/bcm47xx/prom.c

@@ -126,6 +126,7 @@ static __init void prom_init_cmdline(void)
 static __init void prom_init_mem(void)
 {
 	unsigned long mem;
+	unsigned long max;
 
 	/* Figure out memory size by finding aliases.
 	 *
@@ -134,21 +135,26 @@ static __init void prom_init_mem(void)
 	 * want to reuse the memory used by CFE (around 4MB). That means cfe_*
 	 * functions stop to work at some point during the boot, we should only
 	 * call them at the beginning of the boot.
+	 *
+	 * BCM47XX uses 128MB for addressing the ram, if the system contains
+	 * less that that amount of ram it remaps the ram more often into the
+	 * available space.
+	 * Accessing memory after 128MB will cause an exception.
+	 * max contains the biggest possible address supported by the platform.
+	 * If the method wants to try something above we assume 128MB ram.
 	 */
+	max = ((unsigned long)(prom_init) | ((128 << 20) - 1));
 	for (mem = (1 << 20); mem < (128 << 20); mem += (1 << 20)) {
+		if (((unsigned long)(prom_init) + mem) > max) {
+			mem = (128 << 20);
+			printk(KERN_DEBUG "assume 128MB RAM\n");
+			break;
+		}
 		if (*(unsigned long *)((unsigned long)(prom_init) + mem) ==
 		    *(unsigned long *)(prom_init))
 			break;
 	}
 
-	/* Ignoring the last page when ddr size is 128M. Cached
-	 * accesses to last page is causing the processor to prefetch
-	 * using address above 128M stepping out of the ddr address
-	 * space.
-	 */
-	if (mem == 0x8000000)
-		mem -= 0x1000;
-
 	add_memory_region(0, mem, BOOT_MEM_RAM);
 }