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

source code of linux/drivers/of/of_numa.c