sparc64: Refactor OBP cpu scanning code using an iterator.

With feedback from Sam Ravnborg.
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/prom.h

@@ -86,6 +86,7 @@ extern int of_node_to_nid(struct device_node *dp);
 #endif
 
 extern void prom_build_devicetree(void);
+extern void of_populate_present_mask(void);
 
 /* Dummy ref counting routines - to be implemented later */
 static inline struct device_node *of_node_get(struct device_node *node)

arch/sparc/kernel/prom_64.c

@@ -374,52 +374,78 @@ static const char *get_mid_prop(void)
 	return (tlb_type == spitfire ? "upa-portid" : "portid");
 }
 
-struct device_node *of_find_node_by_cpuid(int cpuid)
+static void *of_iterate_over_cpus(void *(*func)(struct device_node *, int, int), int arg)
 {
 	struct device_node *dp;
-	const char *mid_prop = get_mid_prop();
+	const char *mid_prop;
 
+	mid_prop = get_mid_prop();
 	for_each_node_by_type(dp, "cpu") {
-		int id = of_getintprop_default(dp, mid_prop, -1);
+		int cpuid = of_getintprop_default(dp, mid_prop, -1);
 		const char *this_mid_prop = mid_prop;
+		void *ret;
 
-		if (id < 0) {
+		if (cpuid < 0) {
 			this_mid_prop = "cpuid";
-			id = of_getintprop_default(dp, this_mid_prop, -1);
+			cpuid = of_getintprop_default(dp, this_mid_prop, -1);
 		}
-
-		if (id < 0) {
+		if (cpuid < 0) {
 			prom_printf("OF: Serious problem, cpu lacks "
 				    "%s property", this_mid_prop);
 			prom_halt();
 		}
-		if (cpuid == id)
-			return dp;
+#ifdef CONFIG_SMP
+		if (cpuid >= NR_CPUS) {
+			printk(KERN_WARNING "Ignoring CPU %d which is "
+			       ">= NR_CPUS (%d)\n",
+			       cpuid, NR_CPUS);
+			continue;
+		}
+#endif
+		ret = func(dp, cpuid, arg);
+		if (ret)
+			return ret;
 	}
 	return NULL;
 }
 
-void __init of_fill_in_cpu_data(void)
+static void *check_cpu_node(struct device_node *dp, int cpuid, int id)
 {
-	struct device_node *dp;
-	const char *mid_prop;
+	if (id == cpuid)
+		return dp;
+	return NULL;
+}
+
+struct device_node *of_find_node_by_cpuid(int cpuid)
+{
+	return of_iterate_over_cpus(check_cpu_node, cpuid);
+}
+
+static void *record_one_cpu(struct device_node *dp, int cpuid, int arg)
+{
+	ncpus_probed++;
+#ifdef CONFIG_SMP
+	set_cpu_present(cpuid, true);
+	set_cpu_possible(cpuid, true);
+#endif
+	return NULL;
+}
 
+void __init of_populate_present_mask(void)
+{
 	if (tlb_type == hypervisor)
 		return;
 
-	mid_prop = get_mid_prop();
 	ncpus_probed = 0;
-	for_each_node_by_type(dp, "cpu") {
-		int cpuid = of_getintprop_default(dp, mid_prop, -1);
-		const char *this_mid_prop = mid_prop;
-		struct device_node *portid_parent;
+	of_iterate_over_cpus(record_one_cpu, 0);
+}
+
+static void *fill_in_one_cpu(struct device_node *dp, int cpuid, int arg)
+{
+	struct device_node *portid_parent = NULL;
 	int portid = -1;
 
-		portid_parent = NULL;
-		if (cpuid < 0) {
-			this_mid_prop = "cpuid";
-			cpuid = of_getintprop_default(dp, this_mid_prop, -1);
-			if (cpuid >= 0) {
+	if (of_find_property(dp, "cpuid", NULL)) {
 		int limit = 2;
 
 		portid_parent = dp;
@@ -433,30 +459,14 @@ void __init of_fill_in_cpu_data(void)
 				break;
 		}
 	}
-		}
 
-		if (cpuid < 0) {
-			prom_printf("OF: Serious problem, cpu lacks "
-				    "%s property", this_mid_prop);
-			prom_halt();
-		}
-
-		ncpus_probed++;
-
-#ifdef CONFIG_SMP
-		if (cpuid >= NR_CPUS) {
-			printk(KERN_WARNING "Ignoring CPU %d which is "
-			       ">= NR_CPUS (%d)\n",
-			       cpuid, NR_CPUS);
-			continue;
-		}
-#else
+#ifndef CONFIG_SMP
 	/* On uniprocessor we only want the values for the
 	 * real physical cpu the kernel booted onto, however
 	 * cpu_data() only has one entry at index 0.
 	 */
 	if (cpuid != real_hard_smp_processor_id())
-			continue;
+		return NULL;
 	cpuid = 0;
 #endif
 
@@ -517,11 +527,16 @@ void __init of_fill_in_cpu_data(void)
 		cpu_data(cpuid).proc_id = -1;
 	}
 
-#ifdef CONFIG_SMP
-		set_cpu_present(cpuid, true);
-		set_cpu_possible(cpuid, true);
-#endif
-	}
+	return NULL;
+}
+
+void __init of_fill_in_cpu_data(void)
+{
+	if (tlb_type == hypervisor)
+		return;
+
+	of_populate_present_mask();
+	of_iterate_over_cpus(fill_in_one_cpu, 0);
 
 	smp_fill_in_sib_core_maps();
 }