xref: /openbmc/linux/kernel/time/tick-internal.h (revision 8b235f2f)
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 static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev)
40 {
41 	return dev->state_use_accessors;
42 }
43 
44 static inline void clockevent_set_state(struct clock_event_device *dev,
45 					enum clock_event_state state)
46 {
47 	dev->state_use_accessors = state;
48 }
49 
50 extern void clockevents_shutdown(struct clock_event_device *dev);
51 extern void clockevents_exchange_device(struct clock_event_device *old,
52 					struct clock_event_device *new);
53 extern void clockevents_switch_state(struct clock_event_device *dev,
54 				     enum clock_event_state state);
55 extern int clockevents_program_event(struct clock_event_device *dev,
56 				     ktime_t expires, bool force);
57 extern void clockevents_handle_noop(struct clock_event_device *dev);
58 extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
59 extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
60 
61 /* Broadcasting support */
62 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
63 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
64 extern void tick_install_broadcast_device(struct clock_event_device *dev);
65 extern int tick_is_broadcast_device(struct clock_event_device *dev);
66 extern void tick_shutdown_broadcast(unsigned int cpu);
67 extern void tick_suspend_broadcast(void);
68 extern void tick_resume_broadcast(void);
69 extern bool tick_resume_check_broadcast(void);
70 extern void tick_broadcast_init(void);
71 extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
72 extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
73 extern struct tick_device *tick_get_broadcast_device(void);
74 extern struct cpumask *tick_get_broadcast_mask(void);
75 # else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
76 static inline void tick_install_broadcast_device(struct clock_event_device *dev) { }
77 static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
78 static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
79 static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
80 static inline void tick_shutdown_broadcast(unsigned int cpu) { }
81 static inline void tick_suspend_broadcast(void) { }
82 static inline void tick_resume_broadcast(void) { }
83 static inline bool tick_resume_check_broadcast(void) { return false; }
84 static inline void tick_broadcast_init(void) { }
85 static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
86 
87 /* Set the periodic handler in non broadcast mode */
88 static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
89 {
90 	dev->event_handler = tick_handle_periodic;
91 }
92 # endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
93 
94 #else /* !GENERIC_CLOCKEVENTS: */
95 static inline void tick_suspend(void) { }
96 static inline void tick_resume(void) { }
97 #endif /* !GENERIC_CLOCKEVENTS */
98 
99 /* Oneshot related functions */
100 #ifdef CONFIG_TICK_ONESHOT
101 extern void tick_setup_oneshot(struct clock_event_device *newdev,
102 			       void (*handler)(struct clock_event_device *),
103 			       ktime_t nextevt);
104 extern int tick_program_event(ktime_t expires, int force);
105 extern void tick_oneshot_notify(void);
106 extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
107 extern void tick_resume_oneshot(void);
108 static inline bool tick_oneshot_possible(void) { return true; }
109 extern int tick_oneshot_mode_active(void);
110 extern void tick_clock_notify(void);
111 extern int tick_check_oneshot_change(int allow_nohz);
112 extern int tick_init_highres(void);
113 #else /* !CONFIG_TICK_ONESHOT: */
114 static inline
115 void tick_setup_oneshot(struct clock_event_device *newdev,
116 			void (*handler)(struct clock_event_device *),
117 			ktime_t nextevt) { BUG(); }
118 static inline void tick_resume_oneshot(void) { BUG(); }
119 static inline int tick_program_event(ktime_t expires, int force) { return 0; }
120 static inline void tick_oneshot_notify(void) { }
121 static inline bool tick_oneshot_possible(void) { return false; }
122 static inline int tick_oneshot_mode_active(void) { return 0; }
123 static inline void tick_clock_notify(void) { }
124 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
125 #endif /* !CONFIG_TICK_ONESHOT */
126 
127 /* Functions related to oneshot broadcasting */
128 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
129 extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
130 extern void tick_broadcast_switch_to_oneshot(void);
131 extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
132 extern int tick_broadcast_oneshot_active(void);
133 extern void tick_check_oneshot_broadcast_this_cpu(void);
134 bool tick_broadcast_oneshot_available(void);
135 extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
136 #else /* !(BROADCAST && ONESHOT): */
137 static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
138 static inline void tick_broadcast_switch_to_oneshot(void) { }
139 static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
140 static inline int tick_broadcast_oneshot_active(void) { return 0; }
141 static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
142 static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
143 #endif /* !(BROADCAST && ONESHOT) */
144 
145 /* NO_HZ_FULL internal */
146 #ifdef CONFIG_NO_HZ_FULL
147 extern void tick_nohz_init(void);
148 # else
149 static inline void tick_nohz_init(void) { }
150 #endif
151 
152 #ifdef CONFIG_NO_HZ_COMMON
153 extern unsigned long tick_nohz_active;
154 #else
155 #define tick_nohz_active (0)
156 #endif
157 
158 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
159 extern void timers_update_migration(bool update_nohz);
160 #else
161 static inline void timers_update_migration(bool update_nohz) { }
162 #endif
163 
164 DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
165 
166 extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
167