drivers/of/of_numa.c

   1 /*
   2  * OF NUMA Parsing support.
   3  *
   4  * Copyright (C) 2015 - 2016 Cavium Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/of.h>
  20 #include <linux/of_address.h>
  21 #include <linux/nodemask.h>
  22
  23 #include <asm/numa.h>
  24
  25 /* define default numa node to 0 */
  26 #define DEFAULT_NODE 0
  27
  28 /*
  29  * Even though we connect cpus to numa domains later in SMP
  30  * init, we need to know the node ids now for all cpus.
  31 */
  32 static void __init of_numa_parse_cpu_nodes(void)
  33 {
  34         u32 nid;
  35         int r;
  36         struct device_node *cpus;
  37         struct device_node *np = NULL;
  38
  39         cpus = of_find_node_by_path("/cpus");
  40         if (!cpus)
  41                 return;
  42
  43         for_each_child_of_node(cpus, np) {
  44                 /* Skip things that are not CPUs */
  45                 if (of_node_cmp(np->type, "cpu") != 0)
  46                         continue;
  47
  48                 r = of_property_read_u32(np, "numa-node-id", &nid);
  49                 if (r)
  50                         continue;
  51
  52                 pr_debug("NUMA: CPU on %u\n", nid);
  53                 if (nid >= MAX_NUMNODES)
  54                         pr_warn("NUMA: Node id %u exceeds maximum value\n",
  55                                 nid);
  56                 else
  57                         node_set(nid, numa_nodes_parsed);
  58         }
  59 }
  60
  61 static int __init of_numa_parse_memory_nodes(void)
  62 {
  63         struct device_node *np = NULL;
  64         struct resource rsrc;
  65         u32 nid;
  66         int i, r;
  67
  68         for_each_node_by_type(np, "memory") {
  69                 r = of_property_read_u32(np, "numa-node-id", &nid);
  70                 if (r == -EINVAL)
  71                         /*
  72                          * property doesn't exist if -EINVAL, continue
  73                          * looking for more memory nodes with
  74                          * "numa-node-id" property
  75                          */
  76                         continue;
  77
  78                 if (nid >= MAX_NUMNODES) {
  79                         pr_warn("NUMA: Node id %u exceeds maximum value\n", nid);
  80                         r = -EINVAL;
  81                 }
  82
  83                 for (i = 0; !r && !of_address_to_resource(np, i, &rsrc); i++)
  84                         r = numa_add_memblk(nid, rsrc.start, rsrc.end + 1);
  85
  86                 if (!i || r) {
  87                         of_node_put(np);
  88                         pr_err("NUMA: bad property in memory node\n");
  89                         return r ? : -EINVAL;
  90                 }
  91         }
  92
  93         return 0;
  94 }
  95
  96 static int __init of_numa_parse_distance_map_v1(struct device_node *map)
  97 {
  98         const __be32 *matrix;
  99         int entry_count;
 100         int i;
 101
 102         pr_info("NUMA: parsing numa-distance-map-v1\n");
 103
 104         matrix = of_get_property(map, "distance-matrix", NULL);
 105         if (!matrix) {
 106                 pr_err("NUMA: No distance-matrix property in distance-map\n");
 107                 return -EINVAL;
 108         }
 109
 110         entry_count = of_property_count_u32_elems(map, "distance-matrix");
 111         if (entry_count <= 0) {
 112                 pr_err("NUMA: Invalid distance-matrix\n");
 113                 return -EINVAL;
 114         }
 115
 116         for (i = 0; i + 2 < entry_count; i += 3) {
 117                 u32 nodea, nodeb, distance;
 118
 119                 nodea = of_read_number(matrix, 1);
 120                 matrix++;
 121                 nodeb = of_read_number(matrix, 1);
 122                 matrix++;
 123                 distance = of_read_number(matrix, 1);
 124                 matrix++;
 125
 126                 numa_set_distance(nodea, nodeb, distance);
 127                 pr_debug("NUMA:  distance[node%d -> node%d] = %d\n",
 128                          nodea, nodeb, distance);
 129
 130                 /* Set default distance of node B->A same as A->B */
 131                 if (nodeb > nodea)
 132                         numa_set_distance(nodeb, nodea, distance);
 133         }
 134
 135         return 0;
 136 }
 137
 138 static int __init of_numa_parse_distance_map(void)
 139 {
 140         int ret = 0;
 141         struct device_node *np;
 142
 143         np = of_find_compatible_node(NULL, NULL,
 144                                      "numa-distance-map-v1");
 145         if (np)
 146                 ret = of_numa_parse_distance_map_v1(np);
 147
 148         of_node_put(np);
 149         return ret;
 150 }
 151
 152 int of_node_to_nid(struct device_node *device)
 153 {
 154         struct device_node *np;
 155         u32 nid;
 156         int r = -ENODATA;
 157
 158         np = of_node_get(device);
 159
 160         while (np) {
 161                 struct device_node *parent;
 162
 163                 r = of_property_read_u32(np, "numa-node-id", &nid);
 164                 /*
 165                  * -EINVAL indicates the property was not found, and
 166                  *  we walk up the tree trying to find a parent with a
 167                  *  "numa-node-id".  Any other type of error indicates
 168                  *  a bad device tree and we give up.
 169                  */
 170                 if (r != -EINVAL)
 171                         break;
 172
 173                 parent = of_get_parent(np);
 174                 of_node_put(np);
 175                 np = parent;
 176         }
 177         if (np && r)
 178                 pr_warn("NUMA: Invalid \"numa-node-id\" property in node %s\n",
 179                         np->name);
 180         of_node_put(np);
 181
 182         if (!r) {
 183                 if (nid >= MAX_NUMNODES)
 184                         pr_warn("NUMA: Node id %u exceeds maximum value\n",
 185                                 nid);
 186                 else
 187                         return nid;
 188         }
 189
 190         return NUMA_NO_NODE;
 191 }
 192 EXPORT_SYMBOL(of_node_to_nid);
 193
 194 int __init of_numa_init(void)
 195 {
 196         int r;
 197
 198         of_numa_parse_cpu_nodes();
 199         r = of_numa_parse_memory_nodes();
 200         if (r)
 201                 return r;
 202         return of_numa_parse_distance_map();
 203 }