xref: /openbmc/linux/drivers/of/of_numa.c (revision 837dae1b)
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 		r = of_property_read_u32(np, "numa-node-id", &nid);
162 		/*
163 		 * -EINVAL indicates the property was not found, and
164 		 *  we walk up the tree trying to find a parent with a
165 		 *  "numa-node-id".  Any other type of error indicates
166 		 *  a bad device tree and we give up.
167 		 */
168 		if (r != -EINVAL)
169 			break;
170 
171 		np = of_get_next_parent(np);
172 	}
173 	if (np && r)
174 		pr_warn("NUMA: Invalid \"numa-node-id\" property in node %s\n",
175 			np->name);
176 	of_node_put(np);
177 
178 	if (!r)
179 		return nid;
180 
181 	return NUMA_NO_NODE;
182 }
183 EXPORT_SYMBOL(of_node_to_nid);
184 
185 int __init of_numa_init(void)
186 {
187 	int r;
188 
189 	of_numa_parse_cpu_nodes();
190 	r = of_numa_parse_memory_nodes();
191 	if (r)
192 		return r;
193 	return of_numa_parse_distance_map();
194 }
195