EXPORT_SYMBOL(profile_pc);
- /*
- * Return the number of micro-seconds that elapsed since the last
- * update to wall time (aka xtime). The xtime_lock
- * must be at least read-locked when calling this routine.
- */
- static inline unsigned long gettimeoffset (void)
- {
- #ifndef CONFIG_SMP
- /*
- * FIXME: This won't work on smp because jiffies are updated by cpu 0.
- * Once parisc-linux learns the cr16 difference between processors,
- * this could be made to work.
- */
- unsigned long now;
- unsigned long prev_tick;
- unsigned long next_tick;
- unsigned long elapsed_cycles;
- unsigned long usec;
- unsigned long cpuid = smp_processor_id();
- unsigned long cpt = clocktick;
-
- next_tick = cpu_data[cpuid].it_value;
- now = mfctl(16); /* Read the hardware interval timer. */
+ /* clock source code */
- prev_tick = next_tick - cpt;
+ static cycle_t read_cr16(void)
+ {
+ return get_cycles();
+ }
- /* Assume Scenario 1: "now" is later than prev_tick. */
- elapsed_cycles = now - prev_tick;
+ static int cr16_update_callback(void);
- /* aproximate HZ with shifts. Intended math is "(elapsed/clocktick) > HZ" */
- #if HZ == 1000
- if (elapsed_cycles > (cpt << 10) )
- #elif HZ == 250
- if (elapsed_cycles > (cpt << 8) )
- #elif HZ == 100
- if (elapsed_cycles > (cpt << 7) )
- #else
- #warn WTF is HZ set to anyway?
- if (elapsed_cycles > (HZ * cpt) )
- #endif
- {
- /* Scenario 3: clock ticks are missing. */
- printk (KERN_CRIT "gettimeoffset(CPU %ld): missing %ld ticks!"
- " cycles %lX prev/now/next %lX/%lX/%lX clock %lX\n",
- cpuid, elapsed_cycles / cpt,
- elapsed_cycles, prev_tick, now, next_tick, cpt);
- }
+ static struct clocksource clocksource_cr16 = {
+ .name = "cr16",
+ .rating = 300,
+ .read = read_cr16,
+ .mask = CLOCKSOURCE_MASK(BITS_PER_LONG),
+ .mult = 0, /* to be set */
+ .shift = 22,
+ .update_callback = cr16_update_callback,
+ .is_continuous = 1,
+ };
- /* FIXME: Can we improve the precision? Not with PAGE0. */
- usec = (elapsed_cycles * 10000) / PAGE0->mem_10msec;
- return usec;
- #else
- return 0;
- #endif
- }
-
- void
- do_gettimeofday (struct timeval *tv)
+ static int cr16_update_callback(void)
{
- unsigned long flags, seq, usec, sec;
-
- /* Hold xtime_lock and adjust timeval. */
- do {
- seq = read_seqbegin_irqsave(&xtime_lock, flags);
- usec = gettimeoffset();
- sec = xtime.tv_sec;
- usec += (xtime.tv_nsec / 1000);
- } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
-
- /* Move adjusted usec's into sec's. */
- while (usec >= USEC_PER_SEC) {
- usec -= USEC_PER_SEC;
- ++sec;
+ int change = 0;
+
+ /* since the cr16 cycle counters are not syncronized across CPUs,
+ we'll check if we should switch to a safe clocksource: */
+ if (clocksource_cr16.rating != 0 && num_online_cpus() > 1) {
+ clocksource_cr16.rating = 0;
+ clocksource_reselect();
+ change = 1;
}
- /* Return adjusted result. */
- tv->tv_sec = sec;
- tv->tv_usec = usec;
+ return change;
}
- 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
- * done, and then undo it!
- */
- nsec -= gettimeoffset() * 1000;
-
- 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);
-/*
- * XXX: We can do better than this.
- * Returns nanoseconds
- */
-
-unsigned long long sched_clock(void)
-{
- return (unsigned long long)jiffies * (1000000000 / HZ);
-}
-
-
void __init start_cpu_itimer(void)
{
unsigned int cpu = smp_processor_id();