2 /*  linux/include/linux/clocksource.h
6  *  If you are not a clocksource, or timekeeping code, you should
23 struct clocksource;
28 #include <asm/clocksource.h>
31 #include <vdso/clocksource.h>
34  * struct clocksource - hardware abstraction for a free running counter
38  * @read:		Returns a cycle value, passes clocksource as argument
43  * @max_idle_ns:	Maximum idle time permitted by the clocksource (nsecs)
48  * @name:		Pointer to clocksource name
53  *			to assign your clocksource a rating
59  *				A correct and usable clocksource.
61  *				A reasonably fast and accurate clocksource.
63  *				The ideal clocksource. A must-use where
66  * @enable:		Optional function to enable the clocksource
67  * @disable:		Optional function to disable the clocksource
68  * @suspend:		Optional suspend function for the clocksource
69  * @resume:		Optional resume function for the clocksource
70  * @mark_unstable:	Optional function to inform the clocksource driver that
71  *			the watchdog marked the clocksource unstable
75  * @cs_last:		Last clocksource value for clocksource watchdog
77  * @owner:		Module reference, must be set by clocksource in modules
83  * The pointer to the clocksource itself is handed to the read
85  * clocksource into your own struct. Depending on the amount of
89 struct clocksource {  struct
90 	u64			(*read)(struct clocksource *cs);  argument
106 	int			(*enable)(struct clocksource *cs);  argument
107 	void			(*disable)(struct clocksource *cs);  argument
108 	void			(*suspend)(struct clocksource *cs);  argument
109 	void			(*resume)(struct clocksource *cs);  argument
110 	void			(*mark_unstable)(struct clocksource *cs);  argument
111 	void			(*tick_stable)(struct clocksource *cs);  argument
157  * @khz:		Clocksource frequency in KHz
158  * @shift_constant:	Clocksource shift factor
161  * multiplier, given the clocksource shift value
170  * @hz:			Clocksource frequency in Hz
171  * @shift_constant:	Clocksource shift factor
175  * clocksource shift value
183  * clocksource_cyc2ns - converts clocksource cycles to nanoseconds
188  * Converts clocksource cycles to nanoseconds, using the given @mult and @shift.
190  * with absolute clocksource cycles (as those will easily overflow),
191  * but is only intended to be used with relative (delta) clocksource cycles.
201 extern int clocksource_unregister(struct clocksource*);
203 extern void clocksource_change_rating(struct clocksource *cs, int rating);
206 extern struct clocksource * __init clocksource_default_clock(void);
207 extern void clocksource_mark_unstable(struct clocksource *cs);
209 clocksource_start_suspend_timing(struct clocksource *cs, u64 start_cycles);
210 extern u64 clocksource_stop_suspend_timing(struct clocksource *cs, u64 now);
222 __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq);
224 __clocksource_update_freq_scale(struct clocksource *cs, u32 scale, u32 freq);
227  * Don't call this unless you are a default clocksource
230 static inline int __clocksource_register(struct clocksource *cs)  in __clocksource_register()
235 static inline int clocksource_register_hz(struct clocksource *cs, u32 hz)  in clocksource_register_hz()
240 static inline int clocksource_register_khz(struct clocksource *cs, u32 khz)  in clocksource_register_khz()
245 static inline void __clocksource_update_freq_hz(struct clocksource *cs, u32 hz)  in __clocksource_update_freq_hz()
250 static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz)  in __clocksource_update_freq_khz()
256 extern void clocksource_arch_init(struct clocksource *cs);
258 static inline void clocksource_arch_init(struct clocksource *cs) { }  in clocksource_arch_init()
261 extern int timekeeping_notify(struct clocksource *clock);
263 extern u64 clocksource_mmio_readl_up(struct clocksource *);
264 extern u64 clocksource_mmio_readl_down(struct clocksource *);
265 extern u64 clocksource_mmio_readw_up(struct clocksource *);
266 extern u64 clocksource_mmio_readw_down(struct clocksource *);
269 	unsigned long, int, unsigned, u64 (*)(struct clocksource *));