-unsigned int (*mips_hpt_read)(void);
-void (*mips_hpt_init)(unsigned int);
-
-
-/*
- * This version of gettimeofday has microsecond resolution and better than
- * microsecond precision on fast machines with cycle counter.
- */
-void do_gettimeofday(struct timeval *tv)
-{
- unsigned long seq;
- unsigned long lost;
- unsigned long usec, sec;
- unsigned long max_ntp_tick;
-
- do {
- seq = read_seqbegin(&xtime_lock);
-
- usec = do_gettimeoffset();
-
- lost = jiffies - wall_jiffies;
-
- /*
- * If time_adjust is negative then NTP is slowing the clock
- * so make sure not to go into next possible interval.
- * Better to lose some accuracy than have time go backwards..
- */
- if (unlikely(time_adjust < 0)) {
- max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj;
- usec = min(usec, max_ntp_tick);
-
- if (lost)
- usec += lost * max_ntp_tick;
- } else if (unlikely(lost))
- usec += lost * (USEC_PER_SEC / HZ);
-
- sec = xtime.tv_sec;
- usec += (xtime.tv_nsec / 1000);
-
- } while (read_seqretry(&xtime_lock, seq));
-
- while (usec >= 1000000) {
- usec -= 1000000;
- sec++;
- }
-
- tv->tv_sec = sec;
- tv->tv_usec = usec;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-
-int do_settimeofday(struct timespec *tv)
-{
- time_t wtm_sec, sec = tv->tv_sec;
- long wtm_nsec, nsec = tv->tv_nsec;
-
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
- return -EINVAL;
-
- write_seqlock_irq(&xtime_lock);
-
- /*
- * This is revolting. We need to set "xtime" correctly. However,
- * the value in this location is the value at the most recent update
- * of wall time. Discover what correction gettimeofday() would have
- * made, and then undo it!
- */
- nsec -= do_gettimeoffset() * NSEC_PER_USEC;
- nsec -= (jiffies - wall_jiffies) * tick_nsec;
-
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
- ntp_clear();
- write_sequnlock_irq(&xtime_lock);
- clock_was_set();
- return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
-
-/*
- * Gettimeoffset routines. These routines returns the time duration
- * since last timer interrupt in usecs.
- *
- * If the exact CPU counter frequency is known, use fixed_rate_gettimeoffset.
- * Otherwise use calibrate_gettimeoffset()
- *
- * If the CPU does not have the counter register, you can either supply
- * your own gettimeoffset() routine, or use null_gettimeoffset(), which
- * gives the same resolution as HZ.
- */
-
-static unsigned long null_gettimeoffset(void)
-{
- return 0;
-}
-
-
-/* The function pointer to one of the gettimeoffset funcs. */
-unsigned long (*do_gettimeoffset)(void) = null_gettimeoffset;
-
-
-static unsigned long fixed_rate_gettimeoffset(void)
-{
- u32 count;
- unsigned long res;
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (sll32_usecs_per_cycle)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-
-
-/*
- * Cached "1/(clocks per usec) * 2^32" value.
- * It has to be recalculated once each jiffy.
- */
-static unsigned long cached_quotient;
-
-/* Last jiffy when calibrate_divXX_gettimeoffset() was called. */
-static unsigned long last_jiffies;
-
-/*
- * This is moved from dec/time.c:do_ioasic_gettimeoffset() by Maciej.
- */
-static unsigned long calibrate_div32_gettimeoffset(void)
-{
- u32 count;
- unsigned long res, tmp;
- unsigned long quotient;
-
- tmp = jiffies;
-
- quotient = cached_quotient;
-
- if (last_jiffies != tmp) {
- last_jiffies = tmp;
- if (last_jiffies != 0) {
- unsigned long r0;
- do_div64_32(r0, timerhi, timerlo, tmp);
- do_div64_32(quotient, USECS_PER_JIFFY,
- USECS_PER_JIFFY_FRAC, r0);
- cached_quotient = quotient;
- }
- }
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (quotient)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-
-static unsigned long calibrate_div64_gettimeoffset(void)
-{
- u32 count;
- unsigned long res, tmp;
- unsigned long quotient;
-
- tmp = jiffies;
-
- quotient = cached_quotient;
-
- if (last_jiffies != tmp) {
- last_jiffies = tmp;
- if (last_jiffies) {
- unsigned long r0;
- __asm__(".set push\n\t"
- ".set mips3\n\t"
- "lwu %0,%3\n\t"
- "dsll32 %1,%2,0\n\t"
- "or %1,%1,%0\n\t"
- "ddivu $0,%1,%4\n\t"
- "mflo %1\n\t"
- "dsll32 %0,%5,0\n\t"
- "or %0,%0,%6\n\t"
- "ddivu $0,%0,%1\n\t"
- "mflo %0\n\t"
- ".set pop"
- : "=&r" (quotient), "=&r" (r0)
- : "r" (timerhi), "m" (timerlo),
- "r" (tmp), "r" (USECS_PER_JIFFY),
- "r" (USECS_PER_JIFFY_FRAC)
- : "hi", "lo", GCC_REG_ACCUM);
- cached_quotient = quotient;
- }
- }
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (quotient)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-