1 /* SPDX-License-Identifier: GPL-2.0 */
35  * struct clocksource - hardware abstraction for a free running counter
36  *	Provides mostly state-free accessors to the underlying hardware.
48  * @archdata:		Optional arch-specific data
57  *			1-99: Unfit for real use
59  *			100-199: Base level usability.
61  *			200-299: Good.
63  *			300-399: Desired.
65  *			400-499: Perfect
66  *				The ideal clocksource. A must-use where
97 	u64			(*read)(struct clocksource *cs);
115 	int			(*enable)(struct clocksource *cs);
116 	void			(*disable)(struct clocksource *cs);
117 	void			(*suspend)(struct clocksource *cs);
118 	void			(*resume)(struct clocksource *cs);
119 	void			(*mark_unstable)(struct clocksource *cs);
120 	void			(*tick_stable)(struct clocksource *cs);
145 #define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0)
150 	 *  mult/2^shift  = ns/cyc  in clocksource_freq2mult()
151 	 *  mult = ns/cyc * 2^shift  in clocksource_freq2mult()
152 	 *  mult = from/freq * 2^shift  in clocksource_freq2mult()
153 	 *  mult = from * 2^shift / freq  in clocksource_freq2mult()
158 	tmp += freq/2; /* round for do_div */  in clocksource_freq2mult()
165  * clocksource_khz2mult - calculates mult from khz and shift
178  * clocksource_hz2mult - calculates mult from hz and shift
192  * clocksource_cyc2ns - converts clocksource cycles to nanoseconds
202  * XXX - This could use some mult_lxl_ll() asm optimization
212 extern void clocksource_change_rating(struct clocksource *cs, int rating);
216 extern void clocksource_mark_unstable(struct clocksource *cs);
218 clocksource_start_suspend_timing(struct clocksource *cs, u64 start_cycles);
219 extern u64 clocksource_stop_suspend_timing(struct clocksource *cs, u64 now);
231 __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq);
233 __clocksource_update_freq_scale(struct clocksource *cs, u32 scale, u32 freq);
239 static inline int __clocksource_register(struct clocksource *cs)  in __clocksource_register()  argument
241 	return __clocksource_register_scale(cs, 1, 0);  in __clocksource_register()
244 static inline int clocksource_register_hz(struct clocksource *cs, u32 hz)  in clocksource_register_hz()  argument
246 	return __clocksource_register_scale(cs, 1, hz);  in clocksource_register_hz()
249 static inline int clocksource_register_khz(struct clocksource *cs, u32 khz)  in clocksource_register_khz()  argument
251 	return __clocksource_register_scale(cs, 1000, khz);  in clocksource_register_khz()
254 static inline void __clocksource_update_freq_hz(struct clocksource *cs, u32 hz)  in __clocksource_update_freq_hz()  argument
256 	__clocksource_update_freq_scale(cs, 1, hz);  in __clocksource_update_freq_hz()
259 static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz)  in __clocksource_update_freq_khz()  argument
261 	__clocksource_update_freq_scale(cs, 1000, khz);  in __clocksource_update_freq_khz()
265 extern void clocksource_arch_init(struct clocksource *cs);
267 static inline void clocksource_arch_init(struct clocksource *cs) { }  in clocksource_arch_init()  argument
295 void clocksource_verify_percpu(struct clocksource *cs);