MIPS: kexec: Fix random crashes while loading crashkernel

Fixed compilation errors in case of non-KEXEC kernel
Rearranging code so that crashk_res gets updated.
- crashk_res is updated after mips_parse_crashkernel(),
   after resource_init(), which is after arch_mem_init().
- The reserved memory is actually treated as Usable memory,
   Unless we load the crash kernel, everything works.
Signed-off-by: Prem Mallappa <pmallappa@caviumnetworks.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/5805/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/setup.c

@@ -552,6 +552,52 @@ static void __init arch_mem_addpart(phys_t mem, phys_t end, int type)
 	add_memory_region(mem, size, type);
 }
 
+#ifdef CONFIG_KEXEC
+static inline unsigned long long get_total_mem(void)
+{
+	unsigned long long total;
+
+	total = max_pfn - min_low_pfn;
+	return total << PAGE_SHIFT;
+}
+
+static void __init mips_parse_crashkernel(void)
+{
+	unsigned long long total_mem;
+	unsigned long long crash_size, crash_base;
+	int ret;
+
+	total_mem = get_total_mem();
+	ret = parse_crashkernel(boot_command_line, total_mem,
+				&crash_size, &crash_base);
+	if (ret != 0 || crash_size <= 0)
+		return;
+
+	crashk_res.start = crash_base;
+	crashk_res.end	 = crash_base + crash_size - 1;
+}
+
+static void __init request_crashkernel(struct resource *res)
+{
+	int ret;
+
+	ret = request_resource(res, &crashk_res);
+	if (!ret)
+		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
+			(unsigned long)((crashk_res.end -
+					 crashk_res.start + 1) >> 20),
+			(unsigned long)(crashk_res.start  >> 20));
+}
+#else /* !defined(CONFIG_KEXEC)		*/
+static void __init mips_parse_crashkernel(void)
+{
+}
+
+static void __init request_crashkernel(struct resource *res)
+{
+}
+#endif /* !defined(CONFIG_KEXEC)  */
+
 static void __init arch_mem_init(char **cmdline_p)
 {
 	extern void plat_mem_setup(void);
@@ -608,6 +654,8 @@ static void __init arch_mem_init(char **cmdline_p)
 				BOOTMEM_DEFAULT);
 	}
 #endif
+
+	mips_parse_crashkernel();
 #ifdef CONFIG_KEXEC
 	if (crashk_res.start != crashk_res.end)
 		reserve_bootmem(crashk_res.start,
@@ -620,52 +668,6 @@ static void __init arch_mem_init(char **cmdline_p)
 	paging_init();
 }
 
-#ifdef CONFIG_KEXEC
-static inline unsigned long long get_total_mem(void)
-{
-	unsigned long long total;
-
-	total = max_pfn - min_low_pfn;
-	return total << PAGE_SHIFT;
-}
-
-static void __init mips_parse_crashkernel(void)
-{
-	unsigned long long total_mem;
-	unsigned long long crash_size, crash_base;
-	int ret;
-
-	total_mem = get_total_mem();
-	ret = parse_crashkernel(boot_command_line, total_mem,
-				&crash_size, &crash_base);
-	if (ret != 0 || crash_size <= 0)
-		return;
-
-	crashk_res.start = crash_base;
-	crashk_res.end	 = crash_base + crash_size - 1;
-}
-
-static void __init request_crashkernel(struct resource *res)
-{
-	int ret;
-
-	ret = request_resource(res, &crashk_res);
-	if (!ret)
-		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
-			(unsigned long)((crashk_res.end -
-				crashk_res.start + 1) >> 20),
-			(unsigned long)(crashk_res.start  >> 20));
-}
-#else /* !defined(CONFIG_KEXEC)	 */
-static void __init mips_parse_crashkernel(void)
-{
-}
-
-static void __init request_crashkernel(struct resource *res)
-{
-}
-#endif /* !defined(CONFIG_KEXEC)  */
-
 static void __init resource_init(void)
 {
 	int i;
@@ -678,11 +680,6 @@ static void __init resource_init(void)
 	data_resource.start = __pa_symbol(&_etext);
 	data_resource.end = __pa_symbol(&_edata) - 1;
 
-	/*
-	 * Request address space for all standard RAM.
-	 */
-	mips_parse_crashkernel();
-
 	for (i = 0; i < boot_mem_map.nr_map; i++) {
 		struct resource *res;
 		unsigned long start, end;