xref: /openbmc/linux/drivers/base/topology.c (revision 3c8c1539)
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 define_id_show_func(die_id);
49 static DEVICE_ATTR_RO(die_id);
50 
51 define_id_show_func(core_id);
52 static DEVICE_ATTR_RO(core_id);
53 
54 define_siblings_read_func(thread_siblings, sibling_cpumask);
55 static BIN_ATTR_RO(thread_siblings, 0);
56 static BIN_ATTR_RO(thread_siblings_list, 0);
57 
58 define_siblings_read_func(core_cpus, sibling_cpumask);
59 static BIN_ATTR_RO(core_cpus, 0);
60 static BIN_ATTR_RO(core_cpus_list, 0);
61 
62 define_siblings_read_func(core_siblings, core_cpumask);
63 static BIN_ATTR_RO(core_siblings, 0);
64 static BIN_ATTR_RO(core_siblings_list, 0);
65 
66 define_siblings_read_func(die_cpus, die_cpumask);
67 static BIN_ATTR_RO(die_cpus, 0);
68 static BIN_ATTR_RO(die_cpus_list, 0);
69 
70 define_siblings_read_func(package_cpus, core_cpumask);
71 static BIN_ATTR_RO(package_cpus, 0);
72 static BIN_ATTR_RO(package_cpus_list, 0);
73 
74 #ifdef CONFIG_SCHED_BOOK
75 define_id_show_func(book_id);
76 static DEVICE_ATTR_RO(book_id);
77 define_siblings_read_func(book_siblings, book_cpumask);
78 static BIN_ATTR_RO(book_siblings, 0);
79 static BIN_ATTR_RO(book_siblings_list, 0);
80 #endif
81 
82 #ifdef CONFIG_SCHED_DRAWER
83 define_id_show_func(drawer_id);
84 static DEVICE_ATTR_RO(drawer_id);
85 define_siblings_read_func(drawer_siblings, drawer_cpumask);
86 static BIN_ATTR_RO(drawer_siblings, 0);
87 static BIN_ATTR_RO(drawer_siblings_list, 0);
88 #endif
89 
90 static struct bin_attribute *bin_attrs[] = {
91 	&bin_attr_core_cpus,
92 	&bin_attr_core_cpus_list,
93 	&bin_attr_thread_siblings,
94 	&bin_attr_thread_siblings_list,
95 	&bin_attr_core_siblings,
96 	&bin_attr_core_siblings_list,
97 	&bin_attr_die_cpus,
98 	&bin_attr_die_cpus_list,
99 	&bin_attr_package_cpus,
100 	&bin_attr_package_cpus_list,
101 #ifdef CONFIG_SCHED_BOOK
102 	&bin_attr_book_siblings,
103 	&bin_attr_book_siblings_list,
104 #endif
105 #ifdef CONFIG_SCHED_DRAWER
106 	&bin_attr_drawer_siblings,
107 	&bin_attr_drawer_siblings_list,
108 #endif
109 	NULL
110 };
111 
112 static struct attribute *default_attrs[] = {
113 	&dev_attr_physical_package_id.attr,
114 	&dev_attr_die_id.attr,
115 	&dev_attr_core_id.attr,
116 #ifdef CONFIG_SCHED_BOOK
117 	&dev_attr_book_id.attr,
118 #endif
119 #ifdef CONFIG_SCHED_DRAWER
120 	&dev_attr_drawer_id.attr,
121 #endif
122 	NULL
123 };
124 
125 static const struct attribute_group topology_attr_group = {
126 	.attrs = default_attrs,
127 	.bin_attrs = bin_attrs,
128 	.name = "topology"
129 };
130 
131 /* Add/Remove cpu_topology interface for CPU device */
132 static int topology_add_dev(unsigned int cpu)
133 {
134 	struct device *dev = get_cpu_device(cpu);
135 
136 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
137 }
138 
139 static int topology_remove_dev(unsigned int cpu)
140 {
141 	struct device *dev = get_cpu_device(cpu);
142 
143 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
144 	return 0;
145 }
146 
147 static int __init topology_sysfs_init(void)
148 {
149 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
150 				 "base/topology:prepare", topology_add_dev,
151 				 topology_remove_dev);
152 }
153 
154 device_initcall(topology_sysfs_init);
155