text: /*
   * OF NUMA Parsing support.
   *
   * Copyright (C) 2015 - 2016 Cavium Inc.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #include <linux/of.h>
  #include <linux/of_address.h>
  #include <linux/nodemask.h>
  
  #include <asm/numa.h>
  
  /* define default numa node to 0 */
  #define DEFAULT_NODE 0
  
  /*
   * Even though we connect cpus to numa domains later in SMP
   * init, we need to know the node ids now for all cpus.
  */
  static void __init of_numa_parse_cpu_nodes(void)
  {
  	u32 nid;
  	int r;
  	struct device_node *cpus;
  	struct device_node *np = NULL;
  
  	cpus = of_find_node_by_path("/cpus");
  	if (!cpus)
  		return;
  
  	for_each_child_of_node(cpus, np) {
  		/* Skip things that are not CPUs */
  		if (of_node_cmp(np->type, "cpu") != 0)
  			continue;
  
  		r = of_property_read_u32(np, "numa-node-id", &nid);
  		if (r)
  			continue;
  
  		pr_debug("NUMA: CPU on %u\n", nid);
  		if (nid >= MAX_NUMNODES)
  			pr_warn("NUMA: Node id %u exceeds maximum value\n",
  				nid);
  		else
  			node_set(nid, numa_nodes_parsed);
  	}
  }
  
  static int __init of_numa_parse_memory_nodes(void)
  {
  	struct device_node *np = NULL;
  	struct resource rsrc;
  	u32 nid;
  	int r = 0;
  
  	for (;;) {
  		np = of_find_node_by_type(np, "memory");
  		if (!np)
  			break;
  
  		r = of_property_read_u32(np, "numa-node-id", &nid);
  		if (r == -EINVAL)
  			/*
  			 * property doesn't exist if -EINVAL, continue
  			 * looking for more memory nodes with
  			 * "numa-node-id" property
  			 */
  			continue;
  		else if (r)
  			/* some other error */
  			break;
  
  		r = of_address_to_resource(np, 0, &rsrc);
  		if (r) {
  			pr_err("NUMA: bad reg property in memory node\n");
  			break;
  		}
  
  		pr_debug("NUMA:  base = %llx len = %llx, node = %u\n",
  			 rsrc.start, rsrc.end - rsrc.start + 1, nid);
  
  		r = numa_add_memblk(nid, rsrc.start,
  				    rsrc.end - rsrc.start + 1);
  		if (r)
  			break;
  	}
  	of_node_put(np);
  
  	return r;
  }
  
  static int __init of_numa_parse_distance_map_v1(struct device_node *map)
  {
  	const __be32 *matrix;
  	int entry_count;
  	int i;
  
  	pr_info("NUMA: parsing numa-distance-map-v1\n");
  
  	matrix = of_get_property(map, "distance-matrix", NULL);
  	if (!matrix) {
  		pr_err("NUMA: No distance-matrix property in distance-map\n");
  		return -EINVAL;
  	}
  
  	entry_count = of_property_count_u32_elems(map, "distance-matrix");
  	if (entry_count <= 0) {
  		pr_err("NUMA: Invalid distance-matrix\n");
  		return -EINVAL;
  	}
  
  	for (i = 0; i + 2 < entry_count; i += 3) {
  		u32 nodea, nodeb, distance;
  
  		nodea = of_read_number(matrix, 1);
  		matrix++;
  		nodeb = of_read_number(matrix, 1);
  		matrix++;
  		distance = of_read_number(matrix, 1);
  		matrix++;
  
  		numa_set_distance(nodea, nodeb, distance);
  		pr_debug("NUMA:  distance[node%d -> node%d] = %d\n",
  			 nodea, nodeb, distance);
  
  		/* Set default distance of node B->A same as A->B */
  		if (nodeb > nodea)
  			numa_set_distance(nodeb, nodea, distance);
  	}
  
  	return 0;
  }
  
  static int __init of_numa_parse_distance_map(void)
  {
  	int ret = 0;
  	struct device_node *np;
  
  	np = of_find_compatible_node(NULL, NULL,
  				     "numa-distance-map-v1");
  	if (np)
  		ret = of_numa_parse_distance_map_v1(np);
  
  	of_node_put(np);
  	return ret;
  }
  
  int of_node_to_nid(struct device_node *device)
  {
  	struct device_node *np;
  	u32 nid;
  	int r = -ENODATA;
  
  	np = of_node_get(device);
  
  	while (np) {
  		struct device_node *parent;
  
  		r = of_property_read_u32(np, "numa-node-id", &nid);
  		/*
  		 * -EINVAL indicates the property was not found, and
  		 *  we walk up the tree trying to find a parent with a
  		 *  "numa-node-id".  Any other type of error indicates
  		 *  a bad device tree and we give up.
  		 */
  		if (r != -EINVAL)
  			break;
  
  		parent = of_get_parent(np);
  		of_node_put(np);
  		np = parent;
  	}
  	if (np && r)
  		pr_warn("NUMA: Invalid \"numa-node-id\" property in node %s\n",
  			np->name);
  	of_node_put(np);
  
  	if (!r) {
  		if (nid >= MAX_NUMNODES)
  			pr_warn("NUMA: Node id %u exceeds maximum value\n",
  				nid);
  		else
  			return nid;
  	}
  
  	return NUMA_NO_NODE;
  }
  EXPORT_SYMBOL(of_node_to_nid);
  
  int __init of_numa_init(void)
  {
  	int r;
  
  	of_numa_parse_cpu_nodes();
  	r = of_numa_parse_memory_nodes();
  	if (r)
  		return r;
  	return of_numa_parse_distance_map();
  }
  