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9#ifndef _LINUX_CLOCKSOURCE_H
10#define _LINUX_CLOCKSOURCE_H
11
12#include <linux/types.h>
13#include <linux/timex.h>
14#include <linux/time.h>
15#include <linux/list.h>
16#include <linux/cache.h>
17#include <linux/timer.h>
18#include <linux/init.h>
19#include <linux/of.h>
20#include <asm/div64.h>
21#include <asm/io.h>
22
23struct clocksource;
24struct module;
25
26#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
27#include <asm/clocksource.h>
28#endif
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80struct clocksource {
81 u64 (*read)(struct clocksource *cs);
82 u64 mask;
83 u32 mult;
84 u32 shift;
85 u64 max_idle_ns;
86 u32 maxadj;
87#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
88 struct arch_clocksource_data archdata;
89#endif
90 u64 max_cycles;
91 const char *name;
92 struct list_head list;
93 int rating;
94 int (*enable)(struct clocksource *cs);
95 void (*disable)(struct clocksource *cs);
96 unsigned long flags;
97 void (*suspend)(struct clocksource *cs);
98 void (*resume)(struct clocksource *cs);
99 void (*mark_unstable)(struct clocksource *cs);
100 void (*tick_stable)(struct clocksource *cs);
101
102
103#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
104
105 struct list_head wd_list;
106 u64 cs_last;
107 u64 wd_last;
108#endif
109 struct module *owner;
110};
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114
115#define CLOCK_SOURCE_IS_CONTINUOUS 0x01
116#define CLOCK_SOURCE_MUST_VERIFY 0x02
117
118#define CLOCK_SOURCE_WATCHDOG 0x10
119#define CLOCK_SOURCE_VALID_FOR_HRES 0x20
120#define CLOCK_SOURCE_UNSTABLE 0x40
121#define CLOCK_SOURCE_SUSPEND_NONSTOP 0x80
122#define CLOCK_SOURCE_RESELECT 0x100
123
124
125#define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0)
126
127static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from)
128{
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136 u64 tmp = ((u64)from) << shift_constant;
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138 tmp += freq/2;
139 do_div(tmp, freq);
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141 return (u32)tmp;
142}
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152static inline u32 clocksource_khz2mult(u32 khz, u32 shift_constant)
153{
154 return clocksource_freq2mult(khz, shift_constant, NSEC_PER_MSEC);
155}
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166static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant)
167{
168 return clocksource_freq2mult(hz, shift_constant, NSEC_PER_SEC);
169}
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184static inline s64 clocksource_cyc2ns(u64 cycles, u32 mult, u32 shift)
185{
186 return ((u64) cycles * mult) >> shift;
187}
188
189
190extern int clocksource_unregister(struct clocksource*);
191extern void clocksource_touch_watchdog(void);
192extern void clocksource_change_rating(struct clocksource *cs, int rating);
193extern void clocksource_suspend(void);
194extern void clocksource_resume(void);
195extern struct clocksource * __init clocksource_default_clock(void);
196extern void clocksource_mark_unstable(struct clocksource *cs);
197extern void
198clocksource_start_suspend_timing(struct clocksource *cs, u64 start_cycles);
199extern u64 clocksource_stop_suspend_timing(struct clocksource *cs, u64 now);
200
201extern u64
202clocks_calc_max_nsecs(u32 mult, u32 shift, u32 maxadj, u64 mask, u64 *max_cycles);
203extern void
204clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec);
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210extern int
211__clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq);
212extern void
213__clocksource_update_freq_scale(struct clocksource *cs, u32 scale, u32 freq);
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219static inline int __clocksource_register(struct clocksource *cs)
220{
221 return __clocksource_register_scale(cs, 1, 0);
222}
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224static inline int clocksource_register_hz(struct clocksource *cs, u32 hz)
225{
226 return __clocksource_register_scale(cs, 1, hz);
227}
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229static inline int clocksource_register_khz(struct clocksource *cs, u32 khz)
230{
231 return __clocksource_register_scale(cs, 1000, khz);
232}
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234static inline void __clocksource_update_freq_hz(struct clocksource *cs, u32 hz)
235{
236 __clocksource_update_freq_scale(cs, 1, hz);
237}
238
239static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz)
240{
241 __clocksource_update_freq_scale(cs, 1000, khz);
242}
243
244#ifdef CONFIG_ARCH_CLOCKSOURCE_INIT
245extern void clocksource_arch_init(struct clocksource *cs);
246#else
247static inline void clocksource_arch_init(struct clocksource *cs) { }
248#endif
249
250extern int timekeeping_notify(struct clocksource *clock);
251
252extern u64 clocksource_mmio_readl_up(struct clocksource *);
253extern u64 clocksource_mmio_readl_down(struct clocksource *);
254extern u64 clocksource_mmio_readw_up(struct clocksource *);
255extern u64 clocksource_mmio_readw_down(struct clocksource *);
256
257extern int clocksource_mmio_init(void __iomem *, const char *,
258 unsigned long, int, unsigned, u64 (*)(struct clocksource *));
259
260extern int clocksource_i8253_init(void);
261
262#define TIMER_OF_DECLARE(name, compat, fn) \
263 OF_DECLARE_1_RET(timer, name, compat, fn)
264
265#ifdef CONFIG_TIMER_PROBE
266extern void timer_probe(void);
267#else
268static inline void timer_probe(void) {}
269#endif
270
271#define TIMER_ACPI_DECLARE(name, table_id, fn) \
272 ACPI_DECLARE_PROBE_ENTRY(timer, name, table_id, 0, NULL, 0, fn)
273
274#endif
275