1 files changed, 55 insertions, 13 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 5ea4fb718b9..d1da9217427 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -308,7 +308,22 @@ static void __init cacheid_init(void)
  * already provide the required functionality.
  */
 extern struct proc_info_list *lookup_processor_type(unsigned int);
-extern struct machine_desc *lookup_machine_type(unsigned int);
+
+static void __init early_print(const char *str, ...)
+{
+	extern void printascii(const char *);
+	char buf[256];
+	va_list ap;
+
+	va_start(ap, str);
+	vsnprintf(buf, sizeof(buf), str, ap);
+	va_end(ap);
+
+#ifdef CONFIG_DEBUG_LL
+	printascii(buf);
+#endif
+	printk("%s", buf);
+}
 
 static void __init feat_v6_fixup(void)
 {
@@ -426,21 +441,29 @@ void cpu_init(void)
 
 static struct machine_desc * __init setup_machine(unsigned int nr)
 {
-	struct machine_desc *list;
+	extern struct machine_desc __arch_info_begin[], __arch_info_end[];
+	struct machine_desc *p;
 
 	/*
 	 * locate machine in the list of supported machines.
 	 */
-	list = lookup_machine_type(nr);
-	if (!list) {
-		printk("Machine configuration botched (nr %d), unable "
-		       "to continue.\n", nr);
-		while (1);
-	}
+	for (p = __arch_info_begin; p < __arch_info_end; p++)
+		if (nr == p->nr) {
+			printk("Machine: %s\n", p->name);
+			return p;
+		}
 
-	printk("Machine: %s\n", list->name);
+	early_print("\n"
+		"Error: unrecognized/unsupported machine ID (r1 = 0x%08x).\n\n"
+		"Available machine support:\n\nID (hex)\tNAME\n", nr);
 
-	return list;
+	for (p = __arch_info_begin; p < __arch_info_end; p++)
+		early_print("%08x\t%s\n", p->nr, p->name);
+
+	early_print("\nPlease check your kernel config and/or bootloader.\n");
+
+	while (true)
+		/* can't use cpu_relax() here as it may require MMU setup */;
 }
 
 static int __init arm_add_memory(unsigned long start, unsigned long size)
@@ -703,7 +726,7 @@ static struct init_tags {
 	{ tag_size(tag_core), ATAG_CORE },
 	{ 1, PAGE_SIZE, 0xff },
 	{ tag_size(tag_mem32), ATAG_MEM },
-	{ MEM_SIZE, PHYS_OFFSET },
+	{ MEM_SIZE },
 	{ 0, ATAG_NONE }
 };
 
@@ -802,6 +825,8 @@ void __init setup_arch(char **cmdline_p)
 	struct machine_desc *mdesc;
 	char *from = default_command_line;
 
+	init_tags.mem.start = PHYS_OFFSET;
+
 	unwind_init();
 
 	setup_processor();
@@ -814,8 +839,25 @@ void __init setup_arch(char **cmdline_p)
 
 	if (__atags_pointer)
 		tags = phys_to_virt(__atags_pointer);
-	else if (mdesc->boot_params)
-		tags = phys_to_virt(mdesc->boot_params);
+	else if (mdesc->boot_params) {
+#ifdef CONFIG_MMU
+		/*
+		 * We still are executing with a minimal MMU mapping created
+		 * with the presumption that the machine default for this
+		 * is located in the first MB of RAM.  Anything else will
+		 * fault and silently hang the kernel at this point.
+		 */
+		if (mdesc->boot_params < PHYS_OFFSET ||
+		    mdesc->boot_params >= PHYS_OFFSET + SZ_1M) {
+			printk(KERN_WARNING
+			       "Default boot params at physical 0x%08lx out of reach\n",
+			       mdesc->boot_params);
+		} else
+#endif
+		{
+			tags = phys_to_virt(mdesc->boot_params);
+		}
+	}
 
 #if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
 	/*