xref: /openbmc/linux/drivers/base/topology.c (revision dea54fba)
1 /*
2  * driver/base/topology.c - Populate sysfs with cpu topology information
3  *
4  * Written by: Zhang Yanmin, Intel Corporation
5  *
6  * Copyright (C) 2006, Intel Corp.
7  *
8  * All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
18  * NON INFRINGEMENT.  See the GNU General Public License for more
19  * details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  *
25  */
26 #include <linux/mm.h>
27 #include <linux/cpu.h>
28 #include <linux/module.h>
29 #include <linux/hardirq.h>
30 #include <linux/topology.h>
31 
32 #define define_id_show_func(name)				\
33 static ssize_t name##_show(struct device *dev,			\
34 		struct device_attribute *attr, char *buf)	\
35 {								\
36 	return sprintf(buf, "%d\n", topology_##name(dev->id));	\
37 }
38 
39 #define define_siblings_show_map(name, mask)				\
40 static ssize_t name##_show(struct device *dev,				\
41 			   struct device_attribute *attr, char *buf)	\
42 {									\
43 	return cpumap_print_to_pagebuf(false, buf, topology_##mask(dev->id));\
44 }
45 
46 #define define_siblings_show_list(name, mask)				\
47 static ssize_t name##_list_show(struct device *dev,			\
48 				struct device_attribute *attr,		\
49 				char *buf)				\
50 {									\
51 	return cpumap_print_to_pagebuf(true, buf, topology_##mask(dev->id));\
52 }
53 
54 #define define_siblings_show_func(name, mask)	\
55 	define_siblings_show_map(name, mask);	\
56 	define_siblings_show_list(name, mask)
57 
58 define_id_show_func(physical_package_id);
59 static DEVICE_ATTR_RO(physical_package_id);
60 
61 define_id_show_func(core_id);
62 static DEVICE_ATTR_RO(core_id);
63 
64 define_siblings_show_func(thread_siblings, sibling_cpumask);
65 static DEVICE_ATTR_RO(thread_siblings);
66 static DEVICE_ATTR_RO(thread_siblings_list);
67 
68 define_siblings_show_func(core_siblings, core_cpumask);
69 static DEVICE_ATTR_RO(core_siblings);
70 static DEVICE_ATTR_RO(core_siblings_list);
71 
72 #ifdef CONFIG_SCHED_BOOK
73 define_id_show_func(book_id);
74 static DEVICE_ATTR_RO(book_id);
75 define_siblings_show_func(book_siblings, book_cpumask);
76 static DEVICE_ATTR_RO(book_siblings);
77 static DEVICE_ATTR_RO(book_siblings_list);
78 #endif
79 
80 #ifdef CONFIG_SCHED_DRAWER
81 define_id_show_func(drawer_id);
82 static DEVICE_ATTR_RO(drawer_id);
83 define_siblings_show_func(drawer_siblings, drawer_cpumask);
84 static DEVICE_ATTR_RO(drawer_siblings);
85 static DEVICE_ATTR_RO(drawer_siblings_list);
86 #endif
87 
88 static struct attribute *default_attrs[] = {
89 	&dev_attr_physical_package_id.attr,
90 	&dev_attr_core_id.attr,
91 	&dev_attr_thread_siblings.attr,
92 	&dev_attr_thread_siblings_list.attr,
93 	&dev_attr_core_siblings.attr,
94 	&dev_attr_core_siblings_list.attr,
95 #ifdef CONFIG_SCHED_BOOK
96 	&dev_attr_book_id.attr,
97 	&dev_attr_book_siblings.attr,
98 	&dev_attr_book_siblings_list.attr,
99 #endif
100 #ifdef CONFIG_SCHED_DRAWER
101 	&dev_attr_drawer_id.attr,
102 	&dev_attr_drawer_siblings.attr,
103 	&dev_attr_drawer_siblings_list.attr,
104 #endif
105 	NULL
106 };
107 
108 static struct attribute_group topology_attr_group = {
109 	.attrs = default_attrs,
110 	.name = "topology"
111 };
112 
113 /* Add/Remove cpu_topology interface for CPU device */
114 static int topology_add_dev(unsigned int cpu)
115 {
116 	struct device *dev = get_cpu_device(cpu);
117 
118 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
119 }
120 
121 static int topology_remove_dev(unsigned int cpu)
122 {
123 	struct device *dev = get_cpu_device(cpu);
124 
125 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
126 	return 0;
127 }
128 
129 static int topology_sysfs_init(void)
130 {
131 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
132 				 "base/topology:prepare", topology_add_dev,
133 				 topology_remove_dev);
134 }
135 
136 device_initcall(topology_sysfs_init);
137