powerpc/mm: Consolidate numa_enable check and min_common_depth check

If we fail to parse min_common_depth from device tree we boot with
numa disabled. Reflect the same by updating numa_enabled variable
to false. Also, switch all min_common_depth failure check to
if (!numa_enabled) check.

This helps us to avoid checking for both in different code paths.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/numa.c

@@ -232,7 +232,7 @@ static int associativity_to_nid(const __be32 *associativity)
 {
 	int nid = NUMA_NO_NODE;
 
-	if (min_common_depth == -1 || !numa_enabled)
+	if (!numa_enabled)
 		goto out;
 
 	if (of_read_number(associativity, 1) >= min_common_depth)
@@ -648,8 +648,14 @@ static int __init parse_numa_properties(void)
 
 	min_common_depth = find_min_common_depth();
 
-	if (min_common_depth < 0)
+	if (min_common_depth < 0) {
+		/*
+		 * if we fail to parse min_common_depth from device tree
+		 * mark the numa disabled, boot with numa disabled.
+		 */
+		numa_enabled = false;
 		return min_common_depth;
+	}
 
 	dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
 
@@ -765,7 +771,7 @@ void __init dump_numa_cpu_topology(void)
 	unsigned int node;
 	unsigned int cpu, count;
 
-	if (min_common_depth == -1 || !numa_enabled)
+	if (!numa_enabled)
 		return;
 
 	for_each_online_node(node) {
@@ -830,7 +836,7 @@ static void __init find_possible_nodes(void)
 	struct device_node *rtas;
 	u32 numnodes, i;
 
-	if (min_common_depth <= 0 || !numa_enabled)
+	if (!numa_enabled)
 		return;
 
 	rtas = of_find_node_by_path("/rtas");
@@ -1032,7 +1038,7 @@ int hot_add_scn_to_nid(unsigned long scn_addr)
 	struct device_node *memory = NULL;
 	int nid;
 
-	if (!numa_enabled || (min_common_depth < 0))
+	if (!numa_enabled)
 		return first_online_node;
 
 	memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");