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1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * include/linux/cpu.h - generic cpu definition 4 * 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. 8 * 9 * Basic handling of the devices is done in drivers/base/cpu.c 10 * 11 * CPUs are exported via sysfs in the devices/system/cpu 12 * directory. 13 */ 14#ifndef _LINUX_CPU_H_ 15#define _LINUX_CPU_H_ 16 17#include <linux/node.h> 18#include <linux/compiler.h> 19#include <linux/cpumask.h> 20#include <linux/cpuhotplug.h> 21 22struct device; 23struct device_node; 24struct attribute_group; 25 26struct cpu { 27 int node_id; /* The node which contains the CPU */ 28 int hotpluggable; /* creates sysfs control file if hotpluggable */ 29 struct device dev; 30}; 31 32extern void boot_cpu_init(void); 33extern void boot_cpu_state_init(void); 34extern void cpu_init(void); 35extern void trap_init(void); 36 37extern int register_cpu(struct cpu *cpu, int num); 38extern struct device *get_cpu_device(unsigned cpu); 39extern bool cpu_is_hotpluggable(unsigned cpu); 40extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); 41extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, 42 int cpu, unsigned int *thread); 43 44extern int cpu_add_dev_attr(struct device_attribute *attr); 45extern void cpu_remove_dev_attr(struct device_attribute *attr); 46 47extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 48extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 49 50extern ssize_t cpu_show_meltdown(struct device *dev, 51 struct device_attribute *attr, char *buf); 52extern ssize_t cpu_show_spectre_v1(struct device *dev, 53 struct device_attribute *attr, char *buf); 54extern ssize_t cpu_show_spectre_v2(struct device *dev, 55 struct device_attribute *attr, char *buf); 56extern ssize_t cpu_show_spec_store_bypass(struct device *dev, 57 struct device_attribute *attr, char *buf); 58 59extern __printf(4, 5) 60struct device *cpu_device_create(struct device *parent, void *drvdata, 61 const struct attribute_group **groups, 62 const char *fmt, ...); 63#ifdef CONFIG_HOTPLUG_CPU 64extern void unregister_cpu(struct cpu *cpu); 65extern ssize_t arch_cpu_probe(const char *, size_t); 66extern ssize_t arch_cpu_release(const char *, size_t); 67#endif 68 69/* 70 * These states are not related to the core CPU hotplug mechanism. They are 71 * used by various (sub)architectures to track internal state 72 */ 73#define CPU_ONLINE 0x0002 /* CPU is up */ 74#define CPU_UP_PREPARE 0x0003 /* CPU coming up */ 75#define CPU_DEAD 0x0007 /* CPU dead */ 76#define CPU_DEAD_FROZEN 0x0008 /* CPU timed out on unplug */ 77#define CPU_POST_DEAD 0x0009 /* CPU successfully unplugged */ 78#define CPU_BROKEN 0x000B /* CPU did not die properly */ 79 80#ifdef CONFIG_SMP 81extern bool cpuhp_tasks_frozen; 82int cpu_up(unsigned int cpu); 83void notify_cpu_starting(unsigned int cpu); 84extern void cpu_maps_update_begin(void); 85extern void cpu_maps_update_done(void); 86 87#else /* CONFIG_SMP */ 88#define cpuhp_tasks_frozen 0 89 90static inline void cpu_maps_update_begin(void) 91{ 92} 93 94static inline void cpu_maps_update_done(void) 95{ 96} 97 98#endif /* CONFIG_SMP */ 99extern struct bus_type cpu_subsys; 100 101#ifdef CONFIG_HOTPLUG_CPU 102extern void cpus_write_lock(void); 103extern void cpus_write_unlock(void); 104extern void cpus_read_lock(void); 105extern void cpus_read_unlock(void); 106extern void lockdep_assert_cpus_held(void); 107extern void cpu_hotplug_disable(void); 108extern void cpu_hotplug_enable(void); 109void clear_tasks_mm_cpumask(int cpu); 110int cpu_down(unsigned int cpu); 111 112#else /* CONFIG_HOTPLUG_CPU */ 113 114static inline void cpus_write_lock(void) { } 115static inline void cpus_write_unlock(void) { } 116static inline void cpus_read_lock(void) { } 117static inline void cpus_read_unlock(void) { } 118static inline void lockdep_assert_cpus_held(void) { } 119static inline void cpu_hotplug_disable(void) { } 120static inline void cpu_hotplug_enable(void) { } 121#endif /* !CONFIG_HOTPLUG_CPU */ 122 123/* Wrappers which go away once all code is converted */ 124static inline void cpu_hotplug_begin(void) { cpus_write_lock(); } 125static inline void cpu_hotplug_done(void) { cpus_write_unlock(); } 126static inline void get_online_cpus(void) { cpus_read_lock(); } 127static inline void put_online_cpus(void) { cpus_read_unlock(); } 128 129#ifdef CONFIG_PM_SLEEP_SMP 130extern int freeze_secondary_cpus(int primary); 131static inline int disable_nonboot_cpus(void) 132{ 133 return freeze_secondary_cpus(0); 134} 135extern void enable_nonboot_cpus(void); 136#else /* !CONFIG_PM_SLEEP_SMP */ 137static inline int disable_nonboot_cpus(void) { return 0; } 138static inline void enable_nonboot_cpus(void) {} 139#endif /* !CONFIG_PM_SLEEP_SMP */ 140 141void cpu_startup_entry(enum cpuhp_state state); 142 143void cpu_idle_poll_ctrl(bool enable); 144 145/* Attach to any functions which should be considered cpuidle. */ 146#define __cpuidle __attribute__((__section__(".cpuidle.text"))) 147 148bool cpu_in_idle(unsigned long pc); 149 150void arch_cpu_idle(void); 151void arch_cpu_idle_prepare(void); 152void arch_cpu_idle_enter(void); 153void arch_cpu_idle_exit(void); 154void arch_cpu_idle_dead(void); 155 156int cpu_report_state(int cpu); 157int cpu_check_up_prepare(int cpu); 158void cpu_set_state_online(int cpu); 159void play_idle(unsigned long duration_ms); 160 161#ifdef CONFIG_HOTPLUG_CPU 162bool cpu_wait_death(unsigned int cpu, int seconds); 163bool cpu_report_death(void); 164void cpuhp_report_idle_dead(void); 165#else 166static inline void cpuhp_report_idle_dead(void) { } 167#endif /* #ifdef CONFIG_HOTPLUG_CPU */ 168 169#endif /* _LINUX_CPU_H_ */