2 files changed, 92 insertions, 33 deletions

diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
index 32adf7280720..3033c1b30745 100644
--- a/arch/powerpc/include/asm/topology.h
+++ b/arch/powerpc/include/asm/topology.h
@@ -87,6 +87,9 @@ static inline int pcibus_to_node(struct pci_bus *bus)
         .balance_interval       = 1,                                    \
 }
 
+extern int __node_distance(int, int);
+#define node_distance(a, b) __node_distance(a, b)
+
 extern void __init dump_numa_cpu_topology(void);
 
 extern int sysfs_add_device_to_node(struct sys_device *dev, int nid);
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 80d110635d24..f78f19e0a2a4 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -42,6 +42,12 @@ EXPORT_SYMBOL(node_data);
 
 static int min_common_depth;
 static int n_mem_addr_cells, n_mem_size_cells;
+static int form1_affinity;
+
+#define MAX_DISTANCE_REF_POINTS 4
+static int distance_ref_points_depth;
+static const unsigned int *distance_ref_points;
+static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
 
 /*
  * Allocate node_to_cpumask_map based on number of available nodes
@@ -204,6 +210,39 @@ static const u32 *of_get_usable_memory(struct device_node *memory)
         return prop;
 }
 
+int __node_distance(int a, int b)
+{
+        int i;
+        int distance = LOCAL_DISTANCE;
+
+        if (!form1_affinity)
+                return distance;
+
+        for (i = 0; i < distance_ref_points_depth; i++) {
+                if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
+                        break;
+
+                /* Double the distance for each NUMA level */
+                distance *= 2;
+        }
+
+        return distance;
+}
+
+static void initialize_distance_lookup_table(int nid,
+                const unsigned int *associativity)
+{
+        int i;
+
+        if (!form1_affinity)
+                return;
+
+        for (i = 0; i < distance_ref_points_depth; i++) {
+                distance_lookup_table[nid][i] =
+                        associativity[distance_ref_points[i]];
+        }
+}
+
 /* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
  * info is found.
  */
@@ -225,6 +264,10 @@ static int of_node_to_nid_single(struct device_node *device)
         /* POWER4 LPAR uses 0xffff as invalid node */
         if (nid == 0xffff || nid >= MAX_NUMNODES)
                 nid = -1;
+
+        if (nid > 0 && tmp[0] >= distance_ref_points_depth)
+                initialize_distance_lookup_table(nid, tmp);
+
 out:
         return nid;
 }
@@ -251,26 +294,10 @@ int of_node_to_nid(struct device_node *device)
 }
 EXPORT_SYMBOL_GPL(of_node_to_nid);
 
-/*
- * In theory, the "ibm,associativity" property may contain multiple
- * associativity lists because a resource may be multiply connected
- * into the machine.  This resource then has different associativity
- * characteristics relative to its multiple connections.  We ignore
- * this for now.  We also assume that all cpu and memory sets have
- * their distances represented at a common level.  This won't be
- * true for hierarchical NUMA.
- *
- * In any case the ibm,associativity-reference-points should give
- * the correct depth for a normal NUMA system.
- *
- * - Dave Hansen <haveblue@us.ibm.com>
- */
 static int __init find_min_common_depth(void)
 {
-        int depth, index;
-        const unsigned int *ref_points;
+        int depth;
         struct device_node *rtas_root;
-        unsigned int len;
         struct device_node *chosen;
         const char *vec5;
 
@@ -280,18 +307,28 @@ static int __init find_min_common_depth(void)
                 return -1;
 
         /*
-         * this property is 2 32-bit integers, each representing a level of
-         * depth in the associativity nodes.  The first is for an SMP
-         * configuration (should be all 0's) and the second is for a normal
-         * NUMA configuration.
+         * This property is a set of 32-bit integers, each representing
+         * an index into the ibm,associativity nodes.
+         *
+         * With form 0 affinity the first integer is for an SMP configuration
+         * (should be all 0's) and the second is for a normal NUMA
+         * configuration. We have only one level of NUMA.
+         *
+         * With form 1 affinity the first integer is the most significant
+         * NUMA boundary and the following are progressively less significant
+         * boundaries. There can be more than one level of NUMA.
          */
-        index = 1;
-        ref_points = of_get_property(rtas_root,
-                        "ibm,associativity-reference-points", &len);
+        distance_ref_points = of_get_property(rtas_root,
+                                        "ibm,associativity-reference-points",
+                                        &distance_ref_points_depth);
+
+        if (!distance_ref_points) {
+                dbg("NUMA: ibm,associativity-reference-points not found.\n");
+                goto err;
+        }
+
+        distance_ref_points_depth /= sizeof(int);
 
-        /*
-         * For form 1 affinity information we want the first field
-         */
 #define VEC5_AFFINITY_BYTE      5
 #define VEC5_AFFINITY           0x80
         chosen = of_find_node_by_path("/chosen");
@@ -299,19 +336,38 @@ static int __init find_min_common_depth(void)
                 vec5 = of_get_property(chosen, "ibm,architecture-vec-5", NULL);
                 if (vec5 && (vec5[VEC5_AFFINITY_BYTE] & VEC5_AFFINITY)) {
                         dbg("Using form 1 affinity\n");
-                        index = 0;
+                        form1_affinity = 1;
                 }
         }
 
-        if ((len >= 2 * sizeof(unsigned int)) && ref_points) {
-                depth = ref_points[index];
+        if (form1_affinity) {
+                depth = distance_ref_points[0];
         } else {
-                dbg("NUMA: ibm,associativity-reference-points not found.\n");
-                depth = -1;
+                if (distance_ref_points_depth < 2) {
+                        printk(KERN_WARNING "NUMA: "
+                                "short ibm,associativity-reference-points\n");
+                        goto err;
+                }
+
+                depth = distance_ref_points[1];
         }
-        of_node_put(rtas_root);
 
+        /*
+         * Warn and cap if the hardware supports more than
+         * MAX_DISTANCE_REF_POINTS domains.
+         */
+        if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
+                printk(KERN_WARNING "NUMA: distance array capped at "
+                        "%d entries\n", MAX_DISTANCE_REF_POINTS);
+                distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
+        }
+
+        of_node_put(rtas_root);
         return depth;
+
+err:
+        of_node_put(rtas_root);
+        return -1;
 }
 
 static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)