arch/x86/include/asm/timer.h

   1 #ifndef _ASM_X86_TIMER_H
   2 #define _ASM_X86_TIMER_H
   3 #include <linux/pm.h>
   4 #include <linux/percpu.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/math64.h>
   7
   8 #define TICK_SIZE (tick_nsec / 1000)
   9
  10 unsigned long long native_sched_clock(void);
  11 extern int recalibrate_cpu_khz(void);
  12
  13 extern int no_timer_check;
  14
  15 extern bool using_native_sched_clock(void);
  16
  17 /*
  18  * We use the full linear equation: f(x) = a + b*x, in order to allow
  19  * a continuous function in the face of dynamic freq changes.
  20  *
  21  * Continuity means that when our frequency changes our slope (b); we want to
  22  * ensure that: f(t) == f'(t), which gives: a + b*t == a' + b'*t.
  23  *
  24  * Without an offset (a) the above would not be possible.
  25  *
  26  * See the comment near cycles_2_ns() for details on how we compute (b).
  27  */
  28 struct cyc2ns_data {
  29         u32 cyc2ns_mul;
  30         u32 cyc2ns_shift;
  31         u64 cyc2ns_offset;
  32 }; /* 16 bytes */
  33
  34 extern void cyc2ns_read_begin(struct cyc2ns_data *);
  35 extern void cyc2ns_read_end(void);
  36
  37 #endif /* _ASM_X86_TIMER_H */