xref: /openbmc/linux/kernel/time/tick-internal.h (revision 4f3db074)
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 
15 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
16 extern ktime_t tick_next_period;
17 extern ktime_t tick_period;
18 extern int tick_do_timer_cpu __read_mostly;
19 
20 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
21 extern void tick_handle_periodic(struct clock_event_device *dev);
22 extern void tick_check_new_device(struct clock_event_device *dev);
23 extern void tick_shutdown(unsigned int cpu);
24 extern void tick_suspend(void);
25 extern void tick_resume(void);
26 extern bool tick_check_replacement(struct clock_event_device *curdev,
27 				   struct clock_event_device *newdev);
28 extern void tick_install_replacement(struct clock_event_device *dev);
29 extern int tick_is_oneshot_available(void);
30 extern struct tick_device *tick_get_device(int cpu);
31 
32 extern int clockevents_tick_resume(struct clock_event_device *dev);
33 /* Check, if the device is functional or a dummy for broadcast */
34 static inline int tick_device_is_functional(struct clock_event_device *dev)
35 {
36 	return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
37 }
38 
39 extern void clockevents_shutdown(struct clock_event_device *dev);
40 extern void clockevents_exchange_device(struct clock_event_device *old,
41 					struct clock_event_device *new);
42 extern void clockevents_set_state(struct clock_event_device *dev,
43 				 enum clock_event_state state);
44 extern int clockevents_program_event(struct clock_event_device *dev,
45 				     ktime_t expires, bool force);
46 extern void clockevents_handle_noop(struct clock_event_device *dev);
47 extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
48 extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
49 
50 /* Broadcasting support */
51 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
52 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
53 extern void tick_install_broadcast_device(struct clock_event_device *dev);
54 extern int tick_is_broadcast_device(struct clock_event_device *dev);
55 extern void tick_shutdown_broadcast(unsigned int cpu);
56 extern void tick_suspend_broadcast(void);
57 extern void tick_resume_broadcast(void);
58 extern bool tick_resume_check_broadcast(void);
59 extern void tick_broadcast_init(void);
60 extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
61 extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
62 extern struct tick_device *tick_get_broadcast_device(void);
63 extern struct cpumask *tick_get_broadcast_mask(void);
64 # else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
65 static inline void tick_install_broadcast_device(struct clock_event_device *dev) { }
66 static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
67 static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
68 static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
69 static inline void tick_shutdown_broadcast(unsigned int cpu) { }
70 static inline void tick_suspend_broadcast(void) { }
71 static inline void tick_resume_broadcast(void) { }
72 static inline bool tick_resume_check_broadcast(void) { return false; }
73 static inline void tick_broadcast_init(void) { }
74 static 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 */
77 static 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: */
84 static inline void tick_suspend(void) { }
85 static inline void tick_resume(void) { }
86 #endif /* !GENERIC_CLOCKEVENTS */
87 
88 /* Oneshot related functions */
89 #ifdef CONFIG_TICK_ONESHOT
90 extern void tick_setup_oneshot(struct clock_event_device *newdev,
91 			       void (*handler)(struct clock_event_device *),
92 			       ktime_t nextevt);
93 extern int tick_program_event(ktime_t expires, int force);
94 extern void tick_oneshot_notify(void);
95 extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
96 extern void tick_resume_oneshot(void);
97 static inline bool tick_oneshot_possible(void) { return true; }
98 extern int tick_oneshot_mode_active(void);
99 extern void tick_clock_notify(void);
100 extern int tick_check_oneshot_change(int allow_nohz);
101 extern int tick_init_highres(void);
102 #else /* !CONFIG_TICK_ONESHOT: */
103 static inline
104 void tick_setup_oneshot(struct clock_event_device *newdev,
105 			void (*handler)(struct clock_event_device *),
106 			ktime_t nextevt) { BUG(); }
107 static inline void tick_resume_oneshot(void) { BUG(); }
108 static inline int tick_program_event(ktime_t expires, int force) { return 0; }
109 static inline void tick_oneshot_notify(void) { }
110 static inline bool tick_oneshot_possible(void) { return false; }
111 static inline int tick_oneshot_mode_active(void) { return 0; }
112 static inline void tick_clock_notify(void) { }
113 static 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)
118 extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
119 extern void tick_broadcast_switch_to_oneshot(void);
120 extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
121 extern int tick_broadcast_oneshot_active(void);
122 extern void tick_check_oneshot_broadcast_this_cpu(void);
123 bool tick_broadcast_oneshot_available(void);
124 extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
125 #else /* !(BROADCAST && ONESHOT): */
126 static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
127 static inline void tick_broadcast_switch_to_oneshot(void) { }
128 static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
129 static inline int tick_broadcast_oneshot_active(void) { return 0; }
130 static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
131 static 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
136 extern void tick_nohz_init(void);
137 # else
138 static inline void tick_nohz_init(void) { }
139 #endif
140