of_numa.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * OF NUMA Parsing support.
  4 *
  5 * Copyright (C) 2015 - 2016 Cavium Inc.
  6 */
  7
  8#define pr_fmt(fmt) "OF: NUMA: " fmt
  9
 10#include <linux/of.h>
 11#include <linux/of_address.h>
 12#include <linux/nodemask.h>
 13#include <linux/numa_memblks.h>
 14
 15#include <asm/numa.h>
 16
 17/*
 18 * Even though we connect cpus to numa domains later in SMP
 19 * init, we need to know the node ids now for all cpus.
 20*/
 21static void __init of_numa_parse_cpu_nodes(void)
 22{
 23	u32 nid;
 24	int r;
 25	struct device_node *np;
 26
 27	for_each_of_cpu_node(np) {
 28		r = of_property_read_u32(np, "numa-node-id", &nid);
 29		if (r)
 30			continue;
 31
 32		pr_debug("CPU on %u\n", nid);
 33		if (nid >= MAX_NUMNODES)
 34			pr_warn("Node id %u exceeds maximum value\n", nid);
 35		else
 36			node_set(nid, numa_nodes_parsed);
 37	}
 38}
 39
 40static int __init of_numa_parse_memory_nodes(void)
 41{
 42	struct device_node *np = NULL;
 43	struct resource rsrc;
 44	u32 nid;
 45	int i, r = -EINVAL;
 46
 47	for_each_node_by_type(np, "memory") {
 48		r = of_property_read_u32(np, "numa-node-id", &nid);
 49		if (r == -EINVAL)
 50			/*
 51			 * property doesn't exist if -EINVAL, continue
 52			 * looking for more memory nodes with
 53			 * "numa-node-id" property
 54			 */
 55			continue;
 56
 57		if (nid >= MAX_NUMNODES) {
 58			pr_warn("Node id %u exceeds maximum value\n", nid);
 59			r = -EINVAL;
 60		}
 61
 62		for (i = 0; !r && !of_address_to_resource(np, i, &rsrc); i++) {
 63			r = numa_add_memblk(nid, rsrc.start, rsrc.end + 1);
 64			if (!r)
 65				node_set(nid, numa_nodes_parsed);
 66		}
 67
 68		if (!i || r) {
 69			of_node_put(np);
 70			pr_err("bad property in memory node\n");
 71			return r ? : -EINVAL;
 72		}
 73	}
 74
 75	return r;
 76}
 77
 78static int __init of_numa_parse_distance_map_v1(struct device_node *map)
 79{
 80	const __be32 *matrix;
 81	int entry_count;
 82	int i;
 83
 84	pr_info("parsing numa-distance-map-v1\n");
 85
 86	matrix = of_get_property(map, "distance-matrix", NULL);
 87	if (!matrix) {
 88		pr_err("No distance-matrix property in distance-map\n");
 89		return -EINVAL;
 90	}
 91
 92	entry_count = of_property_count_u32_elems(map, "distance-matrix");
 93	if (entry_count <= 0) {
 94		pr_err("Invalid distance-matrix\n");
 95		return -EINVAL;
 96	}
 97
 98	for (i = 0; i + 2 < entry_count; i += 3) {
 99		u32 nodea, nodeb, distance;
100
101		nodea = of_read_number(matrix, 1);
102		matrix++;
103		nodeb = of_read_number(matrix, 1);
104		matrix++;
105		distance = of_read_number(matrix, 1);
106		matrix++;
107
108		if ((nodea == nodeb && distance != LOCAL_DISTANCE) ||
109		    (nodea != nodeb && distance <= LOCAL_DISTANCE)) {
110			pr_err("Invalid distance[node%d -> node%d] = %d\n",
111			       nodea, nodeb, distance);
112			return -EINVAL;
113		}
114
115		node_set(nodea, numa_nodes_parsed);
116
117		numa_set_distance(nodea, nodeb, distance);
118
119		/* Set default distance of node B->A same as A->B */
120		if (nodeb > nodea)
121			numa_set_distance(nodeb, nodea, distance);
122	}
123
124	return 0;
125}
126
127static int __init of_numa_parse_distance_map(void)
128{
129	int ret = 0;
130	struct device_node *np;
131
132	np = of_find_compatible_node(NULL, NULL,
133				     "numa-distance-map-v1");
134	if (np)
135		ret = of_numa_parse_distance_map_v1(np);
136
137	of_node_put(np);
138	return ret;
139}
140
141int of_node_to_nid(struct device_node *device)
142{
143	struct device_node *np;
144	u32 nid;
145	int r = -ENODATA;
146
147	np = of_node_get(device);
148
149	while (np) {
150		r = of_property_read_u32(np, "numa-node-id", &nid);
151		/*
152		 * -EINVAL indicates the property was not found, and
153		 *  we walk up the tree trying to find a parent with a
154		 *  "numa-node-id".  Any other type of error indicates
155		 *  a bad device tree and we give up.
156		 */
157		if (r != -EINVAL)
158			break;
159
160		np = of_get_next_parent(np);
161	}
162	if (np && r)
163		pr_warn("Invalid \"numa-node-id\" property in node %pOFn\n",
164			np);
165	of_node_put(np);
166
167	/*
168	 * If numa=off passed on command line, or with a defective
169	 * device tree, the nid may not be in the set of possible
170	 * nodes.  Check for this case and return NUMA_NO_NODE.
171	 */
172	if (!r && nid < MAX_NUMNODES && node_possible(nid))
173		return nid;
174
175	return NUMA_NO_NODE;
176}
177
178int __init of_numa_init(void)
179{
180	int r;
181
182	of_numa_parse_cpu_nodes();
183	r = of_numa_parse_memory_nodes();
184	if (r)
185		return r;
186	return of_numa_parse_distance_map();
187}