diff options
Diffstat (limited to 'include/linux/timex.h')
| -rw-r--r-- | include/linux/timex.h | 60 |
1 files changed, 0 insertions, 60 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h index da929dbbea2..37ac3ff90fa 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -224,66 +224,6 @@ static inline int ntp_synced(void) __x < 0 ? -(-__x >> __s) : __x >> __s; \ }) - -#ifdef CONFIG_TIME_INTERPOLATION - -#define TIME_SOURCE_CPU 0 -#define TIME_SOURCE_MMIO64 1 -#define TIME_SOURCE_MMIO32 2 -#define TIME_SOURCE_FUNCTION 3 - -/* For proper operations time_interpolator clocks must run slightly slower - * than the standard clock since the interpolator may only correct by having - * time jump forward during a tick. A slower clock is usually a side effect - * of the integer divide of the nanoseconds in a second by the frequency. - * The accuracy of the division can be increased by specifying a shift. - * However, this may cause the clock not to be slow enough. - * The interpolator will self-tune the clock by slowing down if no - * resets occur or speeding up if the time jumps per analysis cycle - * become too high. - * - * Setting jitter compensates for a fluctuating timesource by comparing - * to the last value read from the timesource to insure that an earlier value - * is not returned by a later call. The price to pay - * for the compensation is that the timer routines are not as scalable anymore. - */ - -struct time_interpolator { - u16 source; /* time source flags */ - u8 shift; /* increases accuracy of multiply by shifting. */ - /* Note that bits may be lost if shift is set too high */ - u8 jitter; /* if set compensate for fluctuations */ - u32 nsec_per_cyc; /* set by register_time_interpolator() */ - void *addr; /* address of counter or function */ - cycles_t mask; /* mask the valid bits of the counter */ - unsigned long offset; /* nsec offset at last update of interpolator */ - u64 last_counter; /* counter value in units of the counter at last update */ - cycles_t last_cycle; /* Last timer value if TIME_SOURCE_JITTER is set */ - u64 frequency; /* frequency in counts/second */ - long drift; /* drift in parts-per-million (or -1) */ - unsigned long skips; /* skips forward */ - unsigned long ns_skipped; /* nanoseconds skipped */ - struct time_interpolator *next; -}; - -extern void register_time_interpolator(struct time_interpolator *); -extern void unregister_time_interpolator(struct time_interpolator *); -extern void time_interpolator_reset(void); -extern unsigned long time_interpolator_get_offset(void); -extern void time_interpolator_update(long delta_nsec); - -#else /* !CONFIG_TIME_INTERPOLATION */ - -static inline void time_interpolator_reset(void) -{ -} - -static inline void time_interpolator_update(long delta_nsec) -{ -} - -#endif /* !CONFIG_TIME_INTERPOLATION */ - #define TICK_LENGTH_SHIFT 32 #ifdef CONFIG_NO_HZ |