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8#ifndef _LINUX_CLOCKSOURCE_H
9#define _LINUX_CLOCKSOURCE_H
10
11#include <linux/types.h>
12#include <linux/timex.h>
13#include <linux/time.h>
14#include <linux/list.h>
15#include <linux/cache.h>
16#include <linux/timer.h>
17#include <linux/init.h>
18#include <linux/of.h>
19#include <asm/div64.h>
20#include <asm/io.h>
21
22struct clocksource;
23struct module;
24
25#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
26#include <asm/clocksource.h>
27#endif
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77struct clocksource {
78 cycle_t (*read)(struct clocksource *cs);
79 cycle_t mask;
80 u32 mult;
81 u32 shift;
82 u64 max_idle_ns;
83 u32 maxadj;
84#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
85 struct arch_clocksource_data archdata;
86#endif
87 u64 max_cycles;
88 const char *name;
89 struct list_head list;
90 int rating;
91 int (*enable)(struct clocksource *cs);
92 void (*disable)(struct clocksource *cs);
93 unsigned long flags;
94 void (*suspend)(struct clocksource *cs);
95 void (*resume)(struct clocksource *cs);
96
97
98#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
99
100 struct list_head wd_list;
101 cycle_t cs_last;
102 cycle_t wd_last;
103#endif
104 struct module *owner;
105};
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109
110#define CLOCK_SOURCE_IS_CONTINUOUS 0x01
111#define CLOCK_SOURCE_MUST_VERIFY 0x02
112
113#define CLOCK_SOURCE_WATCHDOG 0x10
114#define CLOCK_SOURCE_VALID_FOR_HRES 0x20
115#define CLOCK_SOURCE_UNSTABLE 0x40
116#define CLOCK_SOURCE_SUSPEND_NONSTOP 0x80
117#define CLOCK_SOURCE_RESELECT 0x100
118
119
120#define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
121
122static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from)
123{
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131 u64 tmp = ((u64)from) << shift_constant;
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133 tmp += freq/2;
134 do_div(tmp, freq);
135
136 return (u32)tmp;
137}
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147static inline u32 clocksource_khz2mult(u32 khz, u32 shift_constant)
148{
149 return clocksource_freq2mult(khz, shift_constant, NSEC_PER_MSEC);
150}
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161static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant)
162{
163 return clocksource_freq2mult(hz, shift_constant, NSEC_PER_SEC);
164}
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176static inline s64 clocksource_cyc2ns(cycle_t cycles, u32 mult, u32 shift)
177{
178 return ((u64) cycles * mult) >> shift;
179}
180
181
182extern int clocksource_unregister(struct clocksource*);
183extern void clocksource_touch_watchdog(void);
184extern void clocksource_change_rating(struct clocksource *cs, int rating);
185extern void clocksource_suspend(void);
186extern void clocksource_resume(void);
187extern struct clocksource * __init clocksource_default_clock(void);
188extern void clocksource_mark_unstable(struct clocksource *cs);
189
190extern u64
191clocks_calc_max_nsecs(u32 mult, u32 shift, u32 maxadj, u64 mask, u64 *max_cycles);
192extern void
193clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec);
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199extern int
200__clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq);
201extern void
202__clocksource_update_freq_scale(struct clocksource *cs, u32 scale, u32 freq);
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208static inline int __clocksource_register(struct clocksource *cs)
209{
210 return __clocksource_register_scale(cs, 1, 0);
211}
212
213static inline int clocksource_register_hz(struct clocksource *cs, u32 hz)
214{
215 return __clocksource_register_scale(cs, 1, hz);
216}
217
218static inline int clocksource_register_khz(struct clocksource *cs, u32 khz)
219{
220 return __clocksource_register_scale(cs, 1000, khz);
221}
222
223static inline void __clocksource_update_freq_hz(struct clocksource *cs, u32 hz)
224{
225 __clocksource_update_freq_scale(cs, 1, hz);
226}
227
228static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz)
229{
230 __clocksource_update_freq_scale(cs, 1000, khz);
231}
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234extern int timekeeping_notify(struct clocksource *clock);
235
236extern cycle_t clocksource_mmio_readl_up(struct clocksource *);
237extern cycle_t clocksource_mmio_readl_down(struct clocksource *);
238extern cycle_t clocksource_mmio_readw_up(struct clocksource *);
239extern cycle_t clocksource_mmio_readw_down(struct clocksource *);
240
241extern int clocksource_mmio_init(void __iomem *, const char *,
242 unsigned long, int, unsigned, cycle_t (*)(struct clocksource *));
243
244extern int clocksource_i8253_init(void);
245
246#define CLOCKSOURCE_OF_DECLARE(name, compat, fn) \
247 OF_DECLARE_1_RET(clksrc, name, compat, fn)
248
249#ifdef CONFIG_CLKSRC_PROBE
250extern void clocksource_probe(void);
251#else
252static inline void clocksource_probe(void) {}
253#endif
254
255#define CLOCKSOURCE_ACPI_DECLARE(name, table_id, fn) \
256 ACPI_DECLARE_PROBE_ENTRY(clksrc, name, table_id, 0, NULL, 0, fn)
257
258#endif
259