xref: /openbmc/linux/drivers/base/topology.c (revision 56b5b1c7)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * driver/base/topology.c - Populate sysfs with cpu topology information
4  *
5  * Written by: Zhang Yanmin, Intel Corporation
6  *
7  * Copyright (C) 2006, Intel Corp.
8  *
9  * All rights reserved.
10  */
11 #include <linux/mm.h>
12 #include <linux/cpu.h>
13 #include <linux/module.h>
14 #include <linux/hardirq.h>
15 #include <linux/topology.h>
16 
17 #define define_id_show_func(name)					\
18 static ssize_t name##_show(struct device *dev,				\
19 			   struct device_attribute *attr, char *buf)	\
20 {									\
21 	return sysfs_emit(buf, "%d\n", topology_##name(dev->id));	\
22 }
23 
24 #define define_siblings_read_func(name, mask)					\
25 static ssize_t name##_read(struct file *file, struct kobject *kobj,		\
26 			   struct bin_attribute *attr, char *buf,		\
27 			   loff_t off, size_t count)				\
28 {										\
29 	struct device *dev = kobj_to_dev(kobj);                                 \
30 										\
31 	return cpumap_print_bitmask_to_buf(buf, topology_##mask(dev->id),	\
32 					   off, count);                         \
33 }										\
34 										\
35 static ssize_t name##_list_read(struct file *file, struct kobject *kobj,	\
36 				struct bin_attribute *attr, char *buf,		\
37 				loff_t off, size_t count)			\
38 {										\
39 	struct device *dev = kobj_to_dev(kobj);					\
40 										\
41 	return cpumap_print_list_to_buf(buf, topology_##mask(dev->id),		\
42 					off, count);				\
43 }
44 
45 define_id_show_func(physical_package_id);
46 static DEVICE_ATTR_RO(physical_package_id);
47 
48 #ifdef TOPOLOGY_DIE_SYSFS
49 define_id_show_func(die_id);
50 static DEVICE_ATTR_RO(die_id);
51 #endif
52 
53 #ifdef TOPOLOGY_CLUSTER_SYSFS
54 define_id_show_func(cluster_id);
55 static DEVICE_ATTR_RO(cluster_id);
56 #endif
57 
58 define_id_show_func(core_id);
59 static DEVICE_ATTR_RO(core_id);
60 
61 define_siblings_read_func(thread_siblings, sibling_cpumask);
62 static BIN_ATTR_RO(thread_siblings, 0);
63 static BIN_ATTR_RO(thread_siblings_list, 0);
64 
65 define_siblings_read_func(core_cpus, sibling_cpumask);
66 static BIN_ATTR_RO(core_cpus, 0);
67 static BIN_ATTR_RO(core_cpus_list, 0);
68 
69 define_siblings_read_func(core_siblings, core_cpumask);
70 static BIN_ATTR_RO(core_siblings, 0);
71 static BIN_ATTR_RO(core_siblings_list, 0);
72 
73 #ifdef TOPOLOGY_CLUSTER_SYSFS
74 define_siblings_read_func(cluster_cpus, cluster_cpumask);
75 static BIN_ATTR_RO(cluster_cpus, 0);
76 static BIN_ATTR_RO(cluster_cpus_list, 0);
77 #endif
78 
79 #ifdef TOPOLOGY_DIE_SYSFS
80 define_siblings_read_func(die_cpus, die_cpumask);
81 static BIN_ATTR_RO(die_cpus, 0);
82 static BIN_ATTR_RO(die_cpus_list, 0);
83 #endif
84 
85 define_siblings_read_func(package_cpus, core_cpumask);
86 static BIN_ATTR_RO(package_cpus, 0);
87 static BIN_ATTR_RO(package_cpus_list, 0);
88 
89 #ifdef TOPOLOGY_BOOK_SYSFS
90 define_id_show_func(book_id);
91 static DEVICE_ATTR_RO(book_id);
92 define_siblings_read_func(book_siblings, book_cpumask);
93 static BIN_ATTR_RO(book_siblings, 0);
94 static BIN_ATTR_RO(book_siblings_list, 0);
95 #endif
96 
97 #ifdef TOPOLOGY_DRAWER_SYSFS
98 define_id_show_func(drawer_id);
99 static DEVICE_ATTR_RO(drawer_id);
100 define_siblings_read_func(drawer_siblings, drawer_cpumask);
101 static BIN_ATTR_RO(drawer_siblings, 0);
102 static BIN_ATTR_RO(drawer_siblings_list, 0);
103 #endif
104 
105 static struct bin_attribute *bin_attrs[] = {
106 	&bin_attr_core_cpus,
107 	&bin_attr_core_cpus_list,
108 	&bin_attr_thread_siblings,
109 	&bin_attr_thread_siblings_list,
110 	&bin_attr_core_siblings,
111 	&bin_attr_core_siblings_list,
112 #ifdef TOPOLOGY_CLUSTER_SYSFS
113 	&bin_attr_cluster_cpus,
114 	&bin_attr_cluster_cpus_list,
115 #endif
116 #ifdef TOPOLOGY_DIE_SYSFS
117 	&bin_attr_die_cpus,
118 	&bin_attr_die_cpus_list,
119 #endif
120 	&bin_attr_package_cpus,
121 	&bin_attr_package_cpus_list,
122 #ifdef TOPOLOGY_BOOK_SYSFS
123 	&bin_attr_book_siblings,
124 	&bin_attr_book_siblings_list,
125 #endif
126 #ifdef TOPOLOGY_DRAWER_SYSFS
127 	&bin_attr_drawer_siblings,
128 	&bin_attr_drawer_siblings_list,
129 #endif
130 	NULL
131 };
132 
133 static struct attribute *default_attrs[] = {
134 	&dev_attr_physical_package_id.attr,
135 #ifdef TOPOLOGY_DIE_SYSFS
136 	&dev_attr_die_id.attr,
137 #endif
138 #ifdef TOPOLOGY_CLUSTER_SYSFS
139 	&dev_attr_cluster_id.attr,
140 #endif
141 	&dev_attr_core_id.attr,
142 #ifdef TOPOLOGY_BOOK_SYSFS
143 	&dev_attr_book_id.attr,
144 #endif
145 #ifdef TOPOLOGY_DRAWER_SYSFS
146 	&dev_attr_drawer_id.attr,
147 #endif
148 	NULL
149 };
150 
151 static const struct attribute_group topology_attr_group = {
152 	.attrs = default_attrs,
153 	.bin_attrs = bin_attrs,
154 	.name = "topology"
155 };
156 
157 /* Add/Remove cpu_topology interface for CPU device */
158 static int topology_add_dev(unsigned int cpu)
159 {
160 	struct device *dev = get_cpu_device(cpu);
161 
162 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
163 }
164 
165 static int topology_remove_dev(unsigned int cpu)
166 {
167 	struct device *dev = get_cpu_device(cpu);
168 
169 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
170 	return 0;
171 }
172 
173 static int __init topology_sysfs_init(void)
174 {
175 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
176 				 "base/topology:prepare", topology_add_dev,
177 				 topology_remove_dev);
178 }
179 
180 device_initcall(topology_sysfs_init);
181