1 /* SPDX-License-Identifier: GPL-2.0 */
3 * include/linux/cpu.h - generic cpu definition
5 * This is mainly for topological representation. We define the
6 * basic 'struct cpu' here, which can be embedded in per-arch
7 * definitions of processors.
9 * Basic handling of the devices is done in drivers/base/cpu.c
11 * CPUs are exported via sysfs in the devices/system/cpu
17 #include <linux/node.h>
18 #include <linux/compiler.h>
19 #include <linux/cpumask.h>
20 #include <linux/cpuhotplug.h>
24 struct attribute_group;
27 int node_id; /* The node which contains the CPU */
28 int hotpluggable; /* creates sysfs control file if hotpluggable */
32 extern void boot_cpu_init(void);
33 extern void boot_cpu_state_init(void);
34 extern void cpu_init(void);
35 extern void trap_init(void);
37 extern int register_cpu(struct cpu *cpu, int num);
38 extern struct device *get_cpu_device(unsigned cpu);
39 extern bool cpu_is_hotpluggable(unsigned cpu);
40 extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
41 extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
42 int cpu, unsigned int *thread);
44 extern int cpu_add_dev_attr(struct device_attribute *attr);
45 extern void cpu_remove_dev_attr(struct device_attribute *attr);
47 extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
48 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
51 struct device *cpu_device_create(struct device *parent, void *drvdata,
52 const struct attribute_group **groups,
53 const char *fmt, ...);
54 #ifdef CONFIG_HOTPLUG_CPU
55 extern void unregister_cpu(struct cpu *cpu);
56 extern ssize_t arch_cpu_probe(const char *, size_t);
57 extern ssize_t arch_cpu_release(const char *, size_t);
61 * These states are not related to the core CPU hotplug mechanism. They are
62 * used by various (sub)architectures to track internal state
64 #define CPU_ONLINE 0x0002 /* CPU is up */
65 #define CPU_UP_PREPARE 0x0003 /* CPU coming up */
66 #define CPU_DEAD 0x0007 /* CPU dead */
67 #define CPU_DEAD_FROZEN 0x0008 /* CPU timed out on unplug */
68 #define CPU_POST_DEAD 0x0009 /* CPU successfully unplugged */
69 #define CPU_BROKEN 0x000B /* CPU did not die properly */
72 extern bool cpuhp_tasks_frozen;
73 int cpu_up(unsigned int cpu);
74 void notify_cpu_starting(unsigned int cpu);
75 extern void cpu_maps_update_begin(void);
76 extern void cpu_maps_update_done(void);
78 #else /* CONFIG_SMP */
79 #define cpuhp_tasks_frozen 0
81 static inline void cpu_maps_update_begin(void)
85 static inline void cpu_maps_update_done(void)
89 #endif /* CONFIG_SMP */
90 extern struct bus_type cpu_subsys;
92 #ifdef CONFIG_HOTPLUG_CPU
93 extern void cpus_write_lock(void);
94 extern void cpus_write_unlock(void);
95 extern void cpus_read_lock(void);
96 extern void cpus_read_unlock(void);
97 extern void lockdep_assert_cpus_held(void);
98 extern void cpu_hotplug_disable(void);
99 extern void cpu_hotplug_enable(void);
100 void clear_tasks_mm_cpumask(int cpu);
101 int cpu_down(unsigned int cpu);
103 #else /* CONFIG_HOTPLUG_CPU */
105 static inline void cpus_write_lock(void) { }
106 static inline void cpus_write_unlock(void) { }
107 static inline void cpus_read_lock(void) { }
108 static inline void cpus_read_unlock(void) { }
109 static inline void lockdep_assert_cpus_held(void) { }
110 static inline void cpu_hotplug_disable(void) { }
111 static inline void cpu_hotplug_enable(void) { }
112 #endif /* !CONFIG_HOTPLUG_CPU */
114 /* Wrappers which go away once all code is converted */
115 static inline void cpu_hotplug_begin(void) { cpus_write_lock(); }
116 static inline void cpu_hotplug_done(void) { cpus_write_unlock(); }
117 static inline void get_online_cpus(void) { cpus_read_lock(); }
118 static inline void put_online_cpus(void) { cpus_read_unlock(); }
120 #ifdef CONFIG_PM_SLEEP_SMP
121 extern int freeze_secondary_cpus(int primary);
122 static inline int disable_nonboot_cpus(void)
124 return freeze_secondary_cpus(0);
126 extern void enable_nonboot_cpus(void);
127 #else /* !CONFIG_PM_SLEEP_SMP */
128 static inline int disable_nonboot_cpus(void) { return 0; }
129 static inline void enable_nonboot_cpus(void) {}
130 #endif /* !CONFIG_PM_SLEEP_SMP */
132 void cpu_startup_entry(enum cpuhp_state state);
134 void cpu_idle_poll_ctrl(bool enable);
136 /* Attach to any functions which should be considered cpuidle. */
137 #define __cpuidle __attribute__((__section__(".cpuidle.text")))
139 bool cpu_in_idle(unsigned long pc);
141 void arch_cpu_idle(void);
142 void arch_cpu_idle_prepare(void);
143 void arch_cpu_idle_enter(void);
144 void arch_cpu_idle_exit(void);
145 void arch_cpu_idle_dead(void);
147 int cpu_report_state(int cpu);
148 int cpu_check_up_prepare(int cpu);
149 void cpu_set_state_online(int cpu);
150 void play_idle(unsigned long duration_ms);
152 #ifdef CONFIG_HOTPLUG_CPU
153 bool cpu_wait_death(unsigned int cpu, int seconds);
154 bool cpu_report_death(void);
155 void cpuhp_report_idle_dead(void);
157 static inline void cpuhp_report_idle_dead(void) { }
158 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
160 #endif /* _LINUX_CPU_H_ */