unsigned long tick_nsec; /* ACTHZ period (nsec) */
static u64 tick_length, tick_length_base;
-/* Don't completely fail for HZ > 500. */
-int tickadj = 500/HZ ? : 1; /* microsecs */
+#define MAX_TICKADJ 500 /* microsecs */
+#define MAX_TICKADJ_SCALED (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \
+ TICK_LENGTH_SHIFT) / NTP_INTERVAL_FREQ)
/*
* phase-lock loop variables
*/
/* TIME_ERROR prevents overwriting the CMOS clock */
-int time_state = TIME_OK; /* clock synchronization status */
+static int time_state = TIME_OK; /* clock synchronization status */
int time_status = STA_UNSYNC; /* clock status bits */
-long time_offset; /* time adjustment (us) */
-long time_constant = 2; /* pll time constant */
-long time_tolerance = MAXFREQ; /* frequency tolerance (ppm) */
-long time_precision = 1; /* clock precision (us) */
+static s64 time_offset; /* time adjustment (ns) */
+static long time_constant = 2; /* pll time constant */
long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */
long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */
-long time_freq = (((NSEC_PER_SEC + HZ/2) % HZ - HZ/2) << SHIFT_USEC) / NSEC_PER_USEC;
- /* frequency offset (scaled ppm)*/
-long time_reftime; /* time at last adjustment (s) */
+long time_freq; /* frequency offset (scaled ppm)*/
+static long time_reftime; /* time at last adjustment (s) */
long time_adjust;
-long time_next_adjust;
+
+#define CLOCK_TICK_OVERFLOW (LATCH * HZ - CLOCK_TICK_RATE)
+#define CLOCK_TICK_ADJUST (((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \
+ (s64)CLOCK_TICK_RATE)
+
+static void ntp_update_frequency(void)
+{
+ u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
+ << TICK_LENGTH_SHIFT;
+ second_length += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT;
+ second_length += (s64)time_freq << (TICK_LENGTH_SHIFT - SHIFT_NSEC);
+
+ tick_length_base = second_length;
+
+ do_div(second_length, HZ);
+ tick_nsec = second_length >> TICK_LENGTH_SHIFT;
+
+ do_div(tick_length_base, NTP_INTERVAL_FREQ);
+}
/**
* ntp_clear - Clears the NTP state variables
ntp_update_frequency();
tick_length = tick_length_base;
-}
-
-#define CLOCK_TICK_OVERFLOW (LATCH * HZ - CLOCK_TICK_RATE)
-#define CLOCK_TICK_ADJUST (((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / (s64)CLOCK_TICK_RATE)
-
-void ntp_update_frequency(void)
-{
- tick_length_base = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) << TICK_LENGTH_SHIFT;
- tick_length_base += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT;
-
- do_div(tick_length_base, HZ);
-
- tick_nsec = tick_length_base >> TICK_LENGTH_SHIFT;
+ time_offset = 0;
}
/*
*/
void second_overflow(void)
{
- long ltemp, time_adj;
+ long time_adj;
/* Bump the maxerror field */
- time_maxerror += time_tolerance >> SHIFT_USEC;
+ time_maxerror += MAXFREQ >> SHIFT_USEC;
if (time_maxerror > NTP_PHASE_LIMIT) {
time_maxerror = NTP_PHASE_LIMIT;
time_status |= STA_UNSYNC;
}
/*
- * Compute the phase adjustment for the next second. In PLL mode, the
- * offset is reduced by a fixed factor times the time constant. In FLL
- * mode the offset is used directly. In either mode, the maximum phase
- * adjustment for each second is clamped so as to spread the adjustment
- * over not more than the number of seconds between updates.
- */
- ltemp = time_offset;
- if (!(time_status & STA_FLL))
- ltemp = shift_right(ltemp, SHIFT_KG + time_constant);
- ltemp = min(ltemp, (MAXPHASE / MINSEC) << SHIFT_UPDATE);
- ltemp = max(ltemp, -(MAXPHASE / MINSEC) << SHIFT_UPDATE);
- time_offset -= ltemp;
- time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
-
- /*
- * Compute the frequency estimate and additional phase adjustment due
- * to frequency error for the next second.
- */
- ltemp = time_freq;
- time_adj += shift_right(ltemp,(SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE));
-
-#if HZ == 100
- /*
- * Compensate for (HZ==100) != (1 << SHIFT_HZ). Add 25% and 3.125% to
- * get 128.125; => only 0.125% error (p. 14)
- */
- time_adj += shift_right(time_adj, 2) + shift_right(time_adj, 5);
-#endif
-#if HZ == 250
- /*
- * Compensate for (HZ==250) != (1 << SHIFT_HZ). Add 1.5625% and
- * 0.78125% to get 255.85938; => only 0.05% error (p. 14)
- */
- time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
-#endif
-#if HZ == 1000
- /*
- * Compensate for (HZ==1000) != (1 << SHIFT_HZ). Add 1.5625% and
- * 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
+ * Compute the phase adjustment for the next second. The offset is
+ * reduced by a fixed factor times the time constant.
*/
- time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
-#endif
tick_length = tick_length_base;
- tick_length += (s64)time_adj << (TICK_LENGTH_SHIFT - (SHIFT_SCALE - 10));
-}
-
-/*
- * Returns how many microseconds we need to add to xtime this tick
- * in doing an adjustment requested with adjtime.
- */
-static long adjtime_adjustment(void)
-{
- long time_adjust_step;
-
- time_adjust_step = time_adjust;
- if (time_adjust_step) {
- /*
- * We are doing an adjtime thing. Prepare time_adjust_step to
- * be within bounds. Note that a positive time_adjust means we
- * want the clock to run faster.
- *
- * Limit the amount of the step to be in the range
- * -tickadj .. +tickadj
- */
- time_adjust_step = min(time_adjust_step, (long)tickadj);
- time_adjust_step = max(time_adjust_step, (long)-tickadj);
- }
- return time_adjust_step;
-}
-
-/* in the NTP reference this is called "hardclock()" */
-void update_ntp_one_tick(void)
-{
- long time_adjust_step;
-
- time_adjust_step = adjtime_adjustment();
- if (time_adjust_step)
- /* Reduce by this step the amount of time left */
- time_adjust -= time_adjust_step;
-
- /* Changes by adjtime() do not take effect till next tick. */
- if (time_next_adjust != 0) {
- time_adjust = time_next_adjust;
- time_next_adjust = 0;
+ time_adj = shift_right(time_offset, SHIFT_PLL + time_constant);
+ time_offset -= time_adj;
+ tick_length += (s64)time_adj << (TICK_LENGTH_SHIFT - SHIFT_UPDATE);
+
+ if (unlikely(time_adjust)) {
+ if (time_adjust > MAX_TICKADJ) {
+ time_adjust -= MAX_TICKADJ;
+ tick_length += MAX_TICKADJ_SCALED;
+ } else if (time_adjust < -MAX_TICKADJ) {
+ time_adjust += MAX_TICKADJ;
+ tick_length -= MAX_TICKADJ_SCALED;
+ } else {
+ tick_length += (s64)(time_adjust * NSEC_PER_USEC /
+ NTP_INTERVAL_FREQ) << TICK_LENGTH_SHIFT;
+ time_adjust = 0;
+ }
}
}
*/
u64 current_tick_length(void)
{
- u64 ret;
-
- /* calculate the finest interval NTP will allow.
- */
- ret = tick_length;
- ret += (u64)(adjtime_adjustment() * 1000) << TICK_LENGTH_SHIFT;
-
- return ret;
+ return tick_length;
}
*/
int do_adjtimex(struct timex *txc)
{
- long ltemp, mtemp, save_adjust;
+ long mtemp, save_adjust, rem;
+ s64 freq_adj, temp64;
int result;
/* In order to modify anything, you gotta be super-user! */
result = time_state; /* mostly `TIME_OK' */
/* Save for later - semantics of adjtime is to return old value */
- save_adjust = time_next_adjust ? time_next_adjust : time_adjust;
+ save_adjust = time_adjust;
#if 0 /* STA_CLOCKERR is never set yet */
time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */
result = -EINVAL;
goto leave;
}
- time_freq = txc->freq;
+ time_freq = ((s64)txc->freq * NSEC_PER_USEC)
+ >> (SHIFT_USEC - SHIFT_NSEC);
}
if (txc->modes & ADJ_MAXERROR) {
result = -EINVAL;
goto leave;
}
- time_constant = txc->constant;
+ time_constant = min(txc->constant + 4, (long)MAXTC);
}
if (txc->modes & ADJ_OFFSET) { /* values checked earlier */
if (txc->modes == ADJ_OFFSET_SINGLESHOT) {
/* adjtime() is independent from ntp_adjtime() */
- if ((time_next_adjust = txc->offset) == 0)
- time_adjust = 0;
+ time_adjust = txc->offset;
}
else if (time_status & STA_PLL) {
- ltemp = txc->offset;
+ time_offset = txc->offset * NSEC_PER_USEC;
/*
* Scale the phase adjustment and
* clamp to the operating range.
*/
- if (ltemp > MAXPHASE)
- time_offset = MAXPHASE << SHIFT_UPDATE;
- else if (ltemp < -MAXPHASE)
- time_offset = -(MAXPHASE << SHIFT_UPDATE);
- else
- time_offset = ltemp << SHIFT_UPDATE;
+ time_offset = min(time_offset, (s64)MAXPHASE * NSEC_PER_USEC);
+ time_offset = max(time_offset, (s64)-MAXPHASE * NSEC_PER_USEC);
/*
* Select whether the frequency is to be controlled
time_reftime = xtime.tv_sec;
mtemp = xtime.tv_sec - time_reftime;
time_reftime = xtime.tv_sec;
- if (time_status & STA_FLL) {
- if (mtemp >= MINSEC) {
- ltemp = (time_offset / mtemp) << (SHIFT_USEC -
- SHIFT_UPDATE);
- time_freq += shift_right(ltemp, SHIFT_KH);
- } else /* calibration interval too short (p. 12) */
- result = TIME_ERROR;
- } else { /* PLL mode */
- if (mtemp < MAXSEC) {
- ltemp *= mtemp;
- time_freq += shift_right(ltemp,(time_constant +
- time_constant +
- SHIFT_KF - SHIFT_USEC));
- } else /* calibration interval too long (p. 12) */
- result = TIME_ERROR;
+
+ freq_adj = time_offset * mtemp;
+ freq_adj = shift_right(freq_adj, time_constant * 2 +
+ (SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
+ if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
+ temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL);
+ if (time_offset < 0) {
+ temp64 = -temp64;
+ do_div(temp64, mtemp);
+ freq_adj -= temp64;
+ } else {
+ do_div(temp64, mtemp);
+ freq_adj += temp64;
+ }
}
- time_freq = min(time_freq, time_tolerance);
- time_freq = max(time_freq, -time_tolerance);
+ freq_adj += time_freq;
+ freq_adj = min(freq_adj, (s64)MAXFREQ_NSEC);
+ time_freq = max(freq_adj, (s64)-MAXFREQ_NSEC);
+ time_offset = div_long_long_rem_signed(time_offset,
+ NTP_INTERVAL_FREQ,
+ &rem);
+ time_offset <<= SHIFT_UPDATE;
} /* STA_PLL */
} /* txc->modes & ADJ_OFFSET */
if (txc->modes & ADJ_TICK)
tick_usec = txc->tick;
- if (txc->modes & ADJ_TICK)
+ if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
ntp_update_frequency();
} /* txc->modes */
leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0)
result = TIME_ERROR;
if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT)
- txc->offset = save_adjust;
- else {
- txc->offset = shift_right(time_offset, SHIFT_UPDATE);
- }
- txc->freq = time_freq;
+ txc->offset = save_adjust;
+ else
+ txc->offset = ((long)shift_right(time_offset, SHIFT_UPDATE)) *
+ NTP_INTERVAL_FREQ / 1000;
+ txc->freq = (time_freq / NSEC_PER_USEC) <<
+ (SHIFT_USEC - SHIFT_NSEC);
txc->maxerror = time_maxerror;
txc->esterror = time_esterror;
txc->status = time_status;
txc->constant = time_constant;
- txc->precision = time_precision;
- txc->tolerance = time_tolerance;
+ txc->precision = 1;
+ txc->tolerance = MAXFREQ;
txc->tick = tick_usec;
/* PPS is not implemented, so these are zero */
projects / powerpc.git / blobdiff