| 1 |
|
| 2 | #ifndef _ASM_X86_TIMER_H
|
| 3 | #define _ASM_X86_TIMER_H
|
| 4 | #include <linux/pm.h>
|
| 5 | #include <linux/percpu.h>
|
| 6 | #include <linux/interrupt.h>
|
| 7 | #include <linux/math64.h>
|
| 8 |
|
| 9 | unsigned long long native_sched_clock(void);
|
| 10 | extern void recalibrate_cpu_khz(void);
|
| 11 |
|
| 12 | extern int no_timer_check;
|
| 13 |
|
| 14 | extern bool using_native_sched_clock(void);
|
| 15 | void paravirt_set_sched_clock(u64 (*func)(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 | };
|
| 33 |
|
| 34 | extern void cyc2ns_read_begin(struct cyc2ns_data *);
|
| 35 | extern void cyc2ns_read_end(void);
|
| 36 |
|
| 37 | #endif
|