arc: use common of_flat_dt_match_machine

Convert arc to use the common of_flat_dt_match_machine function.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/include/asm/mach_desc.h

@@ -51,22 +51,12 @@ struct machine_desc {
 /*
  * Current machine - only accessible during boot.
  */
-extern struct machine_desc *machine_desc;
+extern const struct machine_desc *machine_desc;
 
 /*
  * Machine type table - also only accessible during boot
  */
-extern struct machine_desc __arch_info_begin[], __arch_info_end[];
-#define for_each_machine_desc(p)			\
-	for (p = __arch_info_begin; p < __arch_info_end; p++)
-
-static inline struct machine_desc *default_machine_desc(void)
-{
-	/* the default machine is the last one linked in */
-	if (__arch_info_end - 1 < __arch_info_begin)
-		return NULL;
-	return __arch_info_end - 1;
-}
+extern const struct machine_desc __arch_info_begin[], __arch_info_end[];
 
 /*
  * Set of macros to define architecture features.
@@ -81,6 +71,6 @@ __attribute__((__section__(".arch.info.init"))) = {	\
 #define MACHINE_END				\
 };
 
-extern struct machine_desc *setup_machine_fdt(void *dt);
+extern const struct machine_desc *setup_machine_fdt(void *dt);
 
 #endif

arch/arc/kernel/devtree.c

@@ -18,6 +18,19 @@
 #include <asm/clk.h>
 #include <asm/mach_desc.h>
 
+static const void * __init arch_get_next_mach(const char *const **match)
+{
+	static const struct machine_desc *mdesc = __arch_info_begin;
+	const struct machine_desc *m = mdesc;
+
+	if (m >= __arch_info_end)
+		return NULL;
+
+	mdesc++;
+	*match = m->dt_compat;
+	return m;
+}
+
 /**
  * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
  * @dt:		virtual address pointer to dt blob
@@ -25,66 +38,24 @@
  * If a dtb was passed to the kernel, then use it to choose the correct
  * machine_desc and to setup the system.
  */
-struct machine_desc * __init setup_machine_fdt(void *dt)
+const struct machine_desc * __init setup_machine_fdt(void *dt)
 {
-	struct machine_desc *mdesc = NULL, *mdesc_best = NULL;
-	unsigned int score, mdesc_score = ~1;
+	const struct machine_desc *mdesc;
 	unsigned long dt_root;
-	const char *model, *compat;
 	void *clk;
-	char manufacturer[16];
 	unsigned long len;
 
 	if (!early_init_dt_scan(dt))
 		return NULL;
 
-	dt_root = of_get_flat_dt_root();
-
-	/*
-	 * The kernel could be multi-platform enabled, thus could have many
-	 * "baked-in" machine descriptors. Search thru all for the best
-	 * "compatible" string match.
-	 */
-	for_each_machine_desc(mdesc) {
-		score = of_flat_dt_match(dt_root, mdesc->dt_compat);
-		if (score > 0 && score < mdesc_score) {
-			mdesc_best = mdesc;
-			mdesc_score = score;
-		}
-	}
-	if (!mdesc_best) {
-		const char *prop;
-		long size;
-
-		pr_err("\n unrecognized device tree list:\n[ ");
-
-		prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
-		if (prop) {
-			while (size > 0) {
-				printk("'%s' ", prop);
-				size -= strlen(prop) + 1;
-				prop += strlen(prop) + 1;
-			}
-		}
-		printk("]\n\n");
-
+	mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach);
+	if (!mdesc)
 		machine_halt();
-	}
-
-	/* compat = "<manufacturer>,<model>" */
-	compat =  mdesc_best->dt_compat[0];
-
-	model = strchr(compat, ',');
-	if (model)
-		model++;
-
-	strlcpy(manufacturer, compat, model ? model - compat : strlen(compat));
-
-	pr_info("Board \"%s\" from %s (Manufacturer)\n", model, manufacturer);
 
+	dt_root = of_get_flat_dt_root();
 	clk = of_get_flat_dt_prop(dt_root, "clock-frequency", &len);
 	if (clk)
 		arc_set_core_freq(of_read_ulong(clk, len/4));
 
-	return mdesc_best;
+	return mdesc;
 }

arch/arc/kernel/setup.c

@@ -31,7 +31,7 @@
 int running_on_hw = 1;	/* vs. on ISS */
 
 char __initdata command_line[COMMAND_LINE_SIZE];
-struct machine_desc *machine_desc;
+const struct machine_desc *machine_desc;
 
 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */