1 /* linux/include/linux/clockchips.h
3 * This file contains the structure definitions for clockchips.
5 * If you are not a clockchip, or the time of day code, you should
6 * not be including this file!
8 #ifndef _LINUX_CLOCKCHIPS_H
9 #define _LINUX_CLOCKCHIPS_H
11 /* Clock event notification values */
12 enum clock_event_nofitiers {
14 CLOCK_EVT_NOTIFY_BROADCAST_ON,
15 CLOCK_EVT_NOTIFY_BROADCAST_OFF,
16 CLOCK_EVT_NOTIFY_BROADCAST_FORCE,
17 CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
18 CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
19 CLOCK_EVT_NOTIFY_SUSPEND,
20 CLOCK_EVT_NOTIFY_RESUME,
21 CLOCK_EVT_NOTIFY_CPU_DYING,
22 CLOCK_EVT_NOTIFY_CPU_DEAD,
25 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
27 #include <linux/clocksource.h>
28 #include <linux/cpumask.h>
29 #include <linux/ktime.h>
30 #include <linux/notifier.h>
32 struct clock_event_device;
35 /* Clock event mode commands */
36 enum clock_event_mode {
37 CLOCK_EVT_MODE_UNUSED = 0,
38 CLOCK_EVT_MODE_SHUTDOWN,
39 CLOCK_EVT_MODE_PERIODIC,
40 CLOCK_EVT_MODE_ONESHOT,
41 CLOCK_EVT_MODE_RESUME,
43 /* Legacy ->set_mode() callback doesn't support below modes */
47 * Clock event features
49 #define CLOCK_EVT_FEAT_PERIODIC 0x000001
50 #define CLOCK_EVT_FEAT_ONESHOT 0x000002
51 #define CLOCK_EVT_FEAT_KTIME 0x000004
53 * x86(64) specific misfeatures:
55 * - Clockevent source stops in C3 State and needs broadcast support.
56 * - Local APIC timer is used as a dummy device.
58 #define CLOCK_EVT_FEAT_C3STOP 0x000008
59 #define CLOCK_EVT_FEAT_DUMMY 0x000010
62 * Core shall set the interrupt affinity dynamically in broadcast mode
64 #define CLOCK_EVT_FEAT_DYNIRQ 0x000020
65 #define CLOCK_EVT_FEAT_PERCPU 0x000040
68 * Clockevent device is based on a hrtimer for broadcast
70 #define CLOCK_EVT_FEAT_HRTIMER 0x000080
73 * struct clock_event_device - clock event device descriptor
74 * @event_handler: Assigned by the framework to be called by the low
75 * level handler of the event source
76 * @set_next_event: set next event function using a clocksource delta
77 * @set_next_ktime: set next event function using a direct ktime value
78 * @next_event: local storage for the next event in oneshot mode
79 * @max_delta_ns: maximum delta value in ns
80 * @min_delta_ns: minimum delta value in ns
81 * @mult: nanosecond to cycles multiplier
82 * @shift: nanoseconds to cycles divisor (power of two)
83 * @mode: operating mode assigned by the management code
85 * @retries: number of forced programming retries
86 * @set_mode: legacy set mode function, only for modes <= CLOCK_EVT_MODE_RESUME.
87 * @set_mode_periodic: switch mode to periodic, if !set_mode
88 * @set_mode_oneshot: switch mode to oneshot, if !set_mode
89 * @set_mode_shutdown: switch mode to shutdown, if !set_mode
90 * @set_mode_resume: resume clkevt device, if !set_mode
91 * @broadcast: function to broadcast events
92 * @min_delta_ticks: minimum delta value in ticks stored for reconfiguration
93 * @max_delta_ticks: maximum delta value in ticks stored for reconfiguration
94 * @name: ptr to clock event name
95 * @rating: variable to rate clock event devices
96 * @irq: IRQ number (only for non CPU local devices)
97 * @bound_on: Bound on CPU
98 * @cpumask: cpumask to indicate for which CPUs this device works
99 * @list: list head for the management code
100 * @owner: module reference
102 struct clock_event_device {
103 void (*event_handler)(struct clock_event_device *);
104 int (*set_next_event)(unsigned long evt,
105 struct clock_event_device *);
106 int (*set_next_ktime)(ktime_t expires,
107 struct clock_event_device *);
113 enum clock_event_mode mode;
114 unsigned int features;
115 unsigned long retries;
118 * Mode transition callback(s): Only one of the two groups should be
120 * - set_mode(), only for modes <= CLOCK_EVT_MODE_RESUME.
121 * - set_mode_{shutdown|periodic|oneshot|resume}().
123 void (*set_mode)(enum clock_event_mode mode,
124 struct clock_event_device *);
125 int (*set_mode_periodic)(struct clock_event_device *);
126 int (*set_mode_oneshot)(struct clock_event_device *);
127 int (*set_mode_shutdown)(struct clock_event_device *);
128 int (*set_mode_resume)(struct clock_event_device *);
130 void (*broadcast)(const struct cpumask *mask);
131 void (*suspend)(struct clock_event_device *);
132 void (*resume)(struct clock_event_device *);
133 unsigned long min_delta_ticks;
134 unsigned long max_delta_ticks;
140 const struct cpumask *cpumask;
141 struct list_head list;
142 struct module *owner;
143 } ____cacheline_aligned;
146 * Calculate a multiplication factor for scaled math, which is used to convert
147 * nanoseconds based values to clock ticks:
149 * clock_ticks = (nanoseconds * factor) >> shift.
151 * div_sc is the rearranged equation to calculate a factor from a given clock
152 * ticks / nanoseconds ratio:
154 * factor = (clock_ticks << shift) / nanoseconds
156 static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec,
159 uint64_t tmp = ((uint64_t)ticks) << shift;
162 return (unsigned long) tmp;
165 /* Clock event layer functions */
166 extern u64 clockevent_delta2ns(unsigned long latch,
167 struct clock_event_device *evt);
168 extern void clockevents_register_device(struct clock_event_device *dev);
169 extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu);
171 extern void clockevents_config(struct clock_event_device *dev, u32 freq);
172 extern void clockevents_config_and_register(struct clock_event_device *dev,
173 u32 freq, unsigned long min_delta,
174 unsigned long max_delta);
176 extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq);
178 extern void clockevents_exchange_device(struct clock_event_device *old,
179 struct clock_event_device *new);
180 extern void clockevents_set_mode(struct clock_event_device *dev,
181 enum clock_event_mode mode);
182 extern int clockevents_program_event(struct clock_event_device *dev,
183 ktime_t expires, bool force);
185 extern void clockevents_handle_noop(struct clock_event_device *dev);
188 clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec)
190 return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC,
194 extern void clockevents_suspend(void);
195 extern void clockevents_resume(void);
197 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
198 #ifdef CONFIG_ARCH_HAS_TICK_BROADCAST
199 extern void tick_broadcast(const struct cpumask *mask);
201 #define tick_broadcast NULL
203 extern int tick_receive_broadcast(void);
206 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
207 extern void tick_setup_hrtimer_broadcast(void);
208 extern int tick_check_broadcast_expired(void);
210 static inline int tick_check_broadcast_expired(void) { return 0; }
211 static inline void tick_setup_hrtimer_broadcast(void) {};
214 #ifdef CONFIG_GENERIC_CLOCKEVENTS
215 extern int clockevents_notify(unsigned long reason, void *arg);
217 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; }
220 #else /* CONFIG_GENERIC_CLOCKEVENTS_BUILD */
222 static inline void clockevents_suspend(void) {}
223 static inline void clockevents_resume(void) {}
225 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; }
226 static inline int tick_check_broadcast_expired(void) { return 0; }
227 static inline void tick_setup_hrtimer_broadcast(void) {};