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-rw-r--r--include/linux/timex.h60
1 files changed, 0 insertions, 60 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h
index da929dbbea2a..37ac3ff90faf 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -224,66 +224,6 @@ static inline int ntp_synced(void)
224 __x < 0 ? -(-__x >> __s) : __x >> __s; \ 224 __x < 0 ? -(-__x >> __s) : __x >> __s; \
225}) 225})
226 226
227
228#ifdef CONFIG_TIME_INTERPOLATION
229
230#define TIME_SOURCE_CPU 0
231#define TIME_SOURCE_MMIO64 1
232#define TIME_SOURCE_MMIO32 2
233#define TIME_SOURCE_FUNCTION 3
234
235/* For proper operations time_interpolator clocks must run slightly slower
236 * than the standard clock since the interpolator may only correct by having
237 * time jump forward during a tick. A slower clock is usually a side effect
238 * of the integer divide of the nanoseconds in a second by the frequency.
239 * The accuracy of the division can be increased by specifying a shift.
240 * However, this may cause the clock not to be slow enough.
241 * The interpolator will self-tune the clock by slowing down if no
242 * resets occur or speeding up if the time jumps per analysis cycle
243 * become too high.
244 *
245 * Setting jitter compensates for a fluctuating timesource by comparing
246 * to the last value read from the timesource to insure that an earlier value
247 * is not returned by a later call. The price to pay
248 * for the compensation is that the timer routines are not as scalable anymore.
249 */
250
251struct time_interpolator {
252 u16 source; /* time source flags */
253 u8 shift; /* increases accuracy of multiply by shifting. */
254 /* Note that bits may be lost if shift is set too high */
255 u8 jitter; /* if set compensate for fluctuations */
256 u32 nsec_per_cyc; /* set by register_time_interpolator() */
257 void *addr; /* address of counter or function */
258 cycles_t mask; /* mask the valid bits of the counter */
259 unsigned long offset; /* nsec offset at last update of interpolator */
260 u64 last_counter; /* counter value in units of the counter at last update */
261 cycles_t last_cycle; /* Last timer value if TIME_SOURCE_JITTER is set */
262 u64 frequency; /* frequency in counts/second */
263 long drift; /* drift in parts-per-million (or -1) */
264 unsigned long skips; /* skips forward */
265 unsigned long ns_skipped; /* nanoseconds skipped */
266 struct time_interpolator *next;
267};
268
269extern void register_time_interpolator(struct time_interpolator *);
270extern void unregister_time_interpolator(struct time_interpolator *);
271extern void time_interpolator_reset(void);
272extern unsigned long time_interpolator_get_offset(void);
273extern void time_interpolator_update(long delta_nsec);
274
275#else /* !CONFIG_TIME_INTERPOLATION */
276
277static inline void time_interpolator_reset(void)
278{
279}
280
281static inline void time_interpolator_update(long delta_nsec)
282{
283}
284
285#endif /* !CONFIG_TIME_INTERPOLATION */
286
287#define TICK_LENGTH_SHIFT 32 227#define TICK_LENGTH_SHIFT 32
288 228
289#ifdef CONFIG_NO_HZ 229#ifdef CONFIG_NO_HZ