include/asm-alpha/timex.h

   1 /*
   2  * linux/include/asm-alpha/timex.h
   3  *
   4  * ALPHA architecture timex specifications
   5  */
   6 #ifndef _ASMALPHA_TIMEX_H
   7 #define _ASMALPHA_TIMEX_H
   8
   9 /* With only one or two oddballs, we use the RTC as the ticker, selecting
  10    the 32.768kHz reference clock, which nicely divides down to our HZ.  */
  11 #define CLOCK_TICK_RATE 32768
  12
  13 /*
  14  * Standard way to access the cycle counter.
  15  * Currently only used on SMP for scheduling.
  16  *
  17  * Only the low 32 bits are available as a continuously counting entity.
  18  * But this only means we'll force a reschedule every 8 seconds or so,
  19  * which isn't an evil thing.
  20  */
  21
  22 typedef unsigned int cycles_t;
  23 extern cycles_t cacheflush_time;
  24
  25 static inline cycles_t get_cycles (void)
  26 {
  27         cycles_t ret;
  28         __asm__ __volatile__ ("rpcc %0" : "=r"(ret));
  29         return ret;
  30 }
  31
  32 #endif