1/*
2 * tick internal variable and functions used by low/high res code
3 */
4#include <linux/hrtimer.h>
5#include <linux/tick.h>
6
7#include "timekeeping.h"
8#include "tick-sched.h"
9
10#ifdef CONFIG_GENERIC_CLOCKEVENTS
11
12# define TICK_DO_TIMER_NONE	-1
13# define TICK_DO_TIMER_BOOT	-2
14
15DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
16extern ktime_t tick_next_period;
17extern ktime_t tick_period;
18extern int tick_do_timer_cpu __read_mostly;
19
20extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
21extern void tick_handle_periodic(struct clock_event_device *dev);
22extern void tick_check_new_device(struct clock_event_device *dev);
23extern void tick_shutdown(unsigned int cpu);
24extern void tick_suspend(void);
25extern void tick_resume(void);
26extern bool tick_check_replacement(struct clock_event_device *curdev,
27				   struct clock_event_device *newdev);
28extern void tick_install_replacement(struct clock_event_device *dev);
29extern int tick_is_oneshot_available(void);
30extern struct tick_device *tick_get_device(int cpu);
31
32extern int clockevents_tick_resume(struct clock_event_device *dev);
33/* Check, if the device is functional or a dummy for broadcast */
34static inline int tick_device_is_functional(struct clock_event_device *dev)
35{
36	return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
37}
38
39extern void clockevents_shutdown(struct clock_event_device *dev);
40extern void clockevents_exchange_device(struct clock_event_device *old,
41					struct clock_event_device *new);
42extern void clockevents_set_state(struct clock_event_device *dev,
43				 enum clock_event_state state);
44extern int clockevents_program_event(struct clock_event_device *dev,
45				     ktime_t expires, bool force);
46extern void clockevents_handle_noop(struct clock_event_device *dev);
47extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
48extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
49
50/* Broadcasting support */
51# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
52extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
53extern void tick_install_broadcast_device(struct clock_event_device *dev);
54extern int tick_is_broadcast_device(struct clock_event_device *dev);
55extern void tick_shutdown_broadcast(unsigned int cpu);
56extern void tick_suspend_broadcast(void);
57extern void tick_resume_broadcast(void);
58extern bool tick_resume_check_broadcast(void);
59extern void tick_broadcast_init(void);
60extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
61extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
62extern struct tick_device *tick_get_broadcast_device(void);
63extern struct cpumask *tick_get_broadcast_mask(void);
64# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
65static inline void tick_install_broadcast_device(struct clock_event_device *dev) { }
66static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
67static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
68static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
69static inline void tick_shutdown_broadcast(unsigned int cpu) { }
70static inline void tick_suspend_broadcast(void) { }
71static inline void tick_resume_broadcast(void) { }
72static inline bool tick_resume_check_broadcast(void) { return false; }
73static inline void tick_broadcast_init(void) { }
74static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
75
76/* Set the periodic handler in non broadcast mode */
77static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
78{
79	dev->event_handler = tick_handle_periodic;
80}
81# endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
82
83#else /* !GENERIC_CLOCKEVENTS: */
84static inline void tick_suspend(void) { }
85static inline void tick_resume(void) { }
86#endif /* !GENERIC_CLOCKEVENTS */
87
88/* Oneshot related functions */
89#ifdef CONFIG_TICK_ONESHOT
90extern void tick_setup_oneshot(struct clock_event_device *newdev,
91			       void (*handler)(struct clock_event_device *),
92			       ktime_t nextevt);
93extern int tick_program_event(ktime_t expires, int force);
94extern void tick_oneshot_notify(void);
95extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
96extern void tick_resume_oneshot(void);
97static inline bool tick_oneshot_possible(void) { return true; }
98extern int tick_oneshot_mode_active(void);
99extern void tick_clock_notify(void);
100extern int tick_check_oneshot_change(int allow_nohz);
101extern int tick_init_highres(void);
102#else /* !CONFIG_TICK_ONESHOT: */
103static inline
104void tick_setup_oneshot(struct clock_event_device *newdev,
105			void (*handler)(struct clock_event_device *),
106			ktime_t nextevt) { BUG(); }
107static inline void tick_resume_oneshot(void) { BUG(); }
108static inline int tick_program_event(ktime_t expires, int force) { return 0; }
109static inline void tick_oneshot_notify(void) { }
110static inline bool tick_oneshot_possible(void) { return false; }
111static inline int tick_oneshot_mode_active(void) { return 0; }
112static inline void tick_clock_notify(void) { }
113static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
114#endif /* !CONFIG_TICK_ONESHOT */
115
116/* Functions related to oneshot broadcasting */
117#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
118extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
119extern void tick_broadcast_switch_to_oneshot(void);
120extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
121extern int tick_broadcast_oneshot_active(void);
122extern void tick_check_oneshot_broadcast_this_cpu(void);
123bool tick_broadcast_oneshot_available(void);
124extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
125#else /* !(BROADCAST && ONESHOT): */
126static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
127static inline void tick_broadcast_switch_to_oneshot(void) { }
128static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
129static inline int tick_broadcast_oneshot_active(void) { return 0; }
130static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
131static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
132#endif /* !(BROADCAST && ONESHOT) */
133
134/* NO_HZ_FULL internal */
135#ifdef CONFIG_NO_HZ_FULL
136extern void tick_nohz_init(void);
137# else
138static inline void tick_nohz_init(void) { }
139#endif
140