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 ssize_t cpu_show_meltdown(struct device *dev, 51 struct device_attribute *attr, char *buf); 52 extern ssize_t cpu_show_spectre_v1(struct device *dev, 53 struct device_attribute *attr, char *buf); 54 extern ssize_t cpu_show_spectre_v2(struct device *dev, 55 struct device_attribute *attr, char *buf); 56 extern ssize_t cpu_show_spec_store_bypass(struct device *dev, 57 struct device_attribute *attr, char *buf); 58 59 extern __printf(4, 5) 60 struct device *cpu_device_create(struct device *parent, void *drvdata, 61 const struct attribute_group **groups, 62 const char *fmt, ...); 63 #ifdef CONFIG_HOTPLUG_CPU 64 extern void unregister_cpu(struct cpu *cpu); 65 extern ssize_t arch_cpu_probe(const char *, size_t); 66 extern 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 81 extern bool cpuhp_tasks_frozen; 82 int cpu_up(unsigned int cpu); 83 void notify_cpu_starting(unsigned int cpu); 84 extern void cpu_maps_update_begin(void); 85 extern void cpu_maps_update_done(void); 86 87 #else /* CONFIG_SMP */ 88 #define cpuhp_tasks_frozen 0 89 90 static inline void cpu_maps_update_begin(void) 91 { 92 } 93 94 static inline void cpu_maps_update_done(void) 95 { 96 } 97 98 #endif /* CONFIG_SMP */ 99 extern struct bus_type cpu_subsys; 100 101 #ifdef CONFIG_HOTPLUG_CPU 102 extern void cpus_write_lock(void); 103 extern void cpus_write_unlock(void); 104 extern void cpus_read_lock(void); 105 extern void cpus_read_unlock(void); 106 extern void lockdep_assert_cpus_held(void); 107 extern void cpu_hotplug_disable(void); 108 extern void cpu_hotplug_enable(void); 109 void clear_tasks_mm_cpumask(int cpu); 110 int cpu_down(unsigned int cpu); 111 112 #else /* CONFIG_HOTPLUG_CPU */ 113 114 static inline void cpus_write_lock(void) { } 115 static inline void cpus_write_unlock(void) { } 116 static inline void cpus_read_lock(void) { } 117 static inline void cpus_read_unlock(void) { } 118 static inline void lockdep_assert_cpus_held(void) { } 119 static inline void cpu_hotplug_disable(void) { } 120 static inline void cpu_hotplug_enable(void) { } 121 #endif /* !CONFIG_HOTPLUG_CPU */ 122 123 /* Wrappers which go away once all code is converted */ 124 static inline void cpu_hotplug_begin(void) { cpus_write_lock(); } 125 static inline void cpu_hotplug_done(void) { cpus_write_unlock(); } 126 static inline void get_online_cpus(void) { cpus_read_lock(); } 127 static inline void put_online_cpus(void) { cpus_read_unlock(); } 128 129 #ifdef CONFIG_PM_SLEEP_SMP 130 extern int freeze_secondary_cpus(int primary); 131 static inline int disable_nonboot_cpus(void) 132 { 133 return freeze_secondary_cpus(0); 134 } 135 extern void enable_nonboot_cpus(void); 136 #else /* !CONFIG_PM_SLEEP_SMP */ 137 static inline int disable_nonboot_cpus(void) { return 0; } 138 static inline void enable_nonboot_cpus(void) {} 139 #endif /* !CONFIG_PM_SLEEP_SMP */ 140 141 void cpu_startup_entry(enum cpuhp_state state); 142 143 void cpu_idle_poll_ctrl(bool enable); 144 145 /* Attach to any functions which should be considered cpuidle. */ 146 #define __cpuidle __attribute__((__section__(".cpuidle.text"))) 147 148 bool cpu_in_idle(unsigned long pc); 149 150 void arch_cpu_idle(void); 151 void arch_cpu_idle_prepare(void); 152 void arch_cpu_idle_enter(void); 153 void arch_cpu_idle_exit(void); 154 void arch_cpu_idle_dead(void); 155 156 int cpu_report_state(int cpu); 157 int cpu_check_up_prepare(int cpu); 158 void cpu_set_state_online(int cpu); 159 void play_idle(unsigned long duration_ms); 160 161 #ifdef CONFIG_HOTPLUG_CPU 162 bool cpu_wait_death(unsigned int cpu, int seconds); 163 bool cpu_report_death(void); 164 void cpuhp_report_idle_dead(void); 165 #else 166 static inline void cpuhp_report_idle_dead(void) { } 167 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 168 169 #endif /* _LINUX_CPU_H_ */ 170