xref: /openbmc/linux/drivers/base/topology.c (revision f220d3eb)
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 sprintf(buf, "%d\n", topology_##name(dev->id));	\
22 }
23 
24 #define define_siblings_show_map(name, mask)				\
25 static ssize_t name##_show(struct device *dev,				\
26 			   struct device_attribute *attr, char *buf)	\
27 {									\
28 	return cpumap_print_to_pagebuf(false, buf, topology_##mask(dev->id));\
29 }
30 
31 #define define_siblings_show_list(name, mask)				\
32 static ssize_t name##_list_show(struct device *dev,			\
33 				struct device_attribute *attr,		\
34 				char *buf)				\
35 {									\
36 	return cpumap_print_to_pagebuf(true, buf, topology_##mask(dev->id));\
37 }
38 
39 #define define_siblings_show_func(name, mask)	\
40 	define_siblings_show_map(name, mask);	\
41 	define_siblings_show_list(name, mask)
42 
43 define_id_show_func(physical_package_id);
44 static DEVICE_ATTR_RO(physical_package_id);
45 
46 define_id_show_func(core_id);
47 static DEVICE_ATTR_RO(core_id);
48 
49 define_siblings_show_func(thread_siblings, sibling_cpumask);
50 static DEVICE_ATTR_RO(thread_siblings);
51 static DEVICE_ATTR_RO(thread_siblings_list);
52 
53 define_siblings_show_func(core_siblings, core_cpumask);
54 static DEVICE_ATTR_RO(core_siblings);
55 static DEVICE_ATTR_RO(core_siblings_list);
56 
57 #ifdef CONFIG_SCHED_BOOK
58 define_id_show_func(book_id);
59 static DEVICE_ATTR_RO(book_id);
60 define_siblings_show_func(book_siblings, book_cpumask);
61 static DEVICE_ATTR_RO(book_siblings);
62 static DEVICE_ATTR_RO(book_siblings_list);
63 #endif
64 
65 #ifdef CONFIG_SCHED_DRAWER
66 define_id_show_func(drawer_id);
67 static DEVICE_ATTR_RO(drawer_id);
68 define_siblings_show_func(drawer_siblings, drawer_cpumask);
69 static DEVICE_ATTR_RO(drawer_siblings);
70 static DEVICE_ATTR_RO(drawer_siblings_list);
71 #endif
72 
73 static struct attribute *default_attrs[] = {
74 	&dev_attr_physical_package_id.attr,
75 	&dev_attr_core_id.attr,
76 	&dev_attr_thread_siblings.attr,
77 	&dev_attr_thread_siblings_list.attr,
78 	&dev_attr_core_siblings.attr,
79 	&dev_attr_core_siblings_list.attr,
80 #ifdef CONFIG_SCHED_BOOK
81 	&dev_attr_book_id.attr,
82 	&dev_attr_book_siblings.attr,
83 	&dev_attr_book_siblings_list.attr,
84 #endif
85 #ifdef CONFIG_SCHED_DRAWER
86 	&dev_attr_drawer_id.attr,
87 	&dev_attr_drawer_siblings.attr,
88 	&dev_attr_drawer_siblings_list.attr,
89 #endif
90 	NULL
91 };
92 
93 static const struct attribute_group topology_attr_group = {
94 	.attrs = default_attrs,
95 	.name = "topology"
96 };
97 
98 /* Add/Remove cpu_topology interface for CPU device */
99 static int topology_add_dev(unsigned int cpu)
100 {
101 	struct device *dev = get_cpu_device(cpu);
102 
103 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
104 }
105 
106 static int topology_remove_dev(unsigned int cpu)
107 {
108 	struct device *dev = get_cpu_device(cpu);
109 
110 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
111 	return 0;
112 }
113 
114 static int topology_sysfs_init(void)
115 {
116 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
117 				 "base/topology:prepare", topology_add_dev,
118 				 topology_remove_dev);
119 }
120 
121 device_initcall(topology_sysfs_init);
122