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 22 struct device; 23 struct device_node; 24 struct attribute_group; 25 26 struct 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 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); 36 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); 43 44 extern int cpu_add_dev_attr(struct device_attribute *attr); 45 extern void cpu_remove_dev_attr(struct device_attribute *attr); 46 47 extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 48 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 49 50 extern __printf(4, 5) 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); 58 #endif 59 60 /* 61 * These states are not related to the core CPU hotplug mechanism. They are 62 * used by various (sub)architectures to track internal state 63 */ 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 */ 70 71 #ifdef CONFIG_SMP 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); 77 78 #else /* CONFIG_SMP */ 79 #define cpuhp_tasks_frozen 0 80 81 static inline void cpu_maps_update_begin(void) 82 { 83 } 84 85 static inline void cpu_maps_update_done(void) 86 { 87 } 88 89 #endif /* CONFIG_SMP */ 90 extern struct bus_type cpu_subsys; 91 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); 102 103 #else /* CONFIG_HOTPLUG_CPU */ 104 105 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 */ 113 114 /* 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(); } 119 120 #ifdef CONFIG_PM_SLEEP_SMP 121 extern int freeze_secondary_cpus(int primary); 122 static inline int disable_nonboot_cpus(void) 123 { 124 return freeze_secondary_cpus(0); 125 } 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 */ 131 132 void cpu_startup_entry(enum cpuhp_state state); 133 134 void cpu_idle_poll_ctrl(bool enable); 135 136 /* Attach to any functions which should be considered cpuidle. */ 137 #define __cpuidle __attribute__((__section__(".cpuidle.text"))) 138 139 bool cpu_in_idle(unsigned long pc); 140 141 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); 146 147 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); 151 152 #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); 156 #else 157 static inline void cpuhp_report_idle_dead(void) { } 158 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 159 160 #endif /* _LINUX_CPU_H_ */ 161