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 r = 0;
  67
  68         for (;;) {
  69                 np = of_find_node_by_type(np, "memory");
  70                 if (!np)
  71                         break;
  72
  73                 r = of_property_read_u32(np, "numa-node-id", &nid);
  74                 if (r == -EINVAL)
  75                         /*
  76                          * property doesn't exist if -EINVAL, continue
  77                          * looking for more memory nodes with
  78                          * "numa-node-id" property
  79                          */
  80                         continue;
  81                 else if (r)
  82                         /* some other error */
  83                         break;
  84
  85                 r = of_address_to_resource(np, 0, &rsrc);
  86                 if (r) {
  87                         pr_err("NUMA: bad reg property in memory node\n");
  88                         break;
  89                 }
  90
  91                 pr_debug("NUMA:  base = %llx len = %llx, node = %u\n",
  92                          rsrc.start, rsrc.end - rsrc.start + 1, nid);
  93
  94                 r = numa_add_memblk(nid, rsrc.start,
  95                                     rsrc.end - rsrc.start + 1);
  96                 if (r)
  97                         break;
  98         }
  99         of_node_put(np);
 100
 101         return r;
 102 }
 103
 104 static int __init of_numa_parse_distance_map_v1(struct device_node *map)
 105 {
 106         const __be32 *matrix;
 107         int entry_count;
 108         int i;
 109
 110         pr_info("NUMA: parsing numa-distance-map-v1\n");
 111
 112         matrix = of_get_property(map, "distance-matrix", NULL);
 113         if (!matrix) {
 114                 pr_err("NUMA: No distance-matrix property in distance-map\n");
 115                 return -EINVAL;
 116         }
 117
 118         entry_count = of_property_count_u32_elems(map, "distance-matrix");
 119         if (entry_count <= 0) {
 120                 pr_err("NUMA: Invalid distance-matrix\n");
 121                 return -EINVAL;
 122         }
 123
 124         for (i = 0; i + 2 < entry_count; i += 3) {
 125                 u32 nodea, nodeb, distance;
 126
 127                 nodea = of_read_number(matrix, 1);
 128                 matrix++;
 129                 nodeb = of_read_number(matrix, 1);
 130                 matrix++;
 131                 distance = of_read_number(matrix, 1);
 132                 matrix++;
 133
 134                 numa_set_distance(nodea, nodeb, distance);
 135                 pr_debug("NUMA:  distance[node%d -> node%d] = %d\n",
 136                          nodea, nodeb, distance);
 137
 138                 /* Set default distance of node B->A same as A->B */
 139                 if (nodeb > nodea)
 140                         numa_set_distance(nodeb, nodea, distance);
 141         }
 142
 143         return 0;
 144 }
 145
 146 static int __init of_numa_parse_distance_map(void)
 147 {
 148         int ret = 0;
 149         struct device_node *np;
 150
 151         np = of_find_compatible_node(NULL, NULL,
 152                                      "numa-distance-map-v1");
 153         if (np)
 154                 ret = of_numa_parse_distance_map_v1(np);
 155
 156         of_node_put(np);
 157         return ret;
 158 }
 159
 160 int of_node_to_nid(struct device_node *device)
 161 {
 162         struct device_node *np;
 163         u32 nid;
 164         int r = -ENODATA;
 165
 166         np = of_node_get(device);
 167
 168         while (np) {
 169                 struct device_node *parent;
 170
 171                 r = of_property_read_u32(np, "numa-node-id", &nid);
 172                 /*
 173                  * -EINVAL indicates the property was not found, and
 174                  *  we walk up the tree trying to find a parent with a
 175                  *  "numa-node-id".  Any other type of error indicates
 176                  *  a bad device tree and we give up.
 177                  */
 178                 if (r != -EINVAL)
 179                         break;
 180
 181                 parent = of_get_parent(np);
 182                 of_node_put(np);
 183                 np = parent;
 184         }
 185         if (np && r)
 186                 pr_warn("NUMA: Invalid \"numa-node-id\" property in node %s\n",
 187                         np->name);
 188         of_node_put(np);
 189
 190         if (!r) {
 191                 if (nid >= MAX_NUMNODES)
 192                         pr_warn("NUMA: Node id %u exceeds maximum value\n",
 193                                 nid);
 194                 else
 195                         return nid;
 196         }
 197
 198         return NUMA_NO_NODE;
 199 }
 200 EXPORT_SYMBOL(of_node_to_nid);
 201
 202 int __init of_numa_init(void)
 203 {
 204         int r;
 205
 206         of_numa_parse_cpu_nodes();
 207         r = of_numa_parse_memory_nodes();
 208         if (r)
 209                 return r;
 210         return of_numa_parse_distance_map();
 211 }