1/* SPDX-License-Identifier: GPL-2.0 */
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#define TICK_SIZE (tick_nsec / 1000)
10
11unsigned long long native_sched_clock(void);
12extern void recalibrate_cpu_khz(void);
13
14extern int no_timer_check;
15
16extern bool using_native_sched_clock(void);
17
18/*
19 * We use the full linear equation: f(x) = a + b*x, in order to allow
20 * a continuous function in the face of dynamic freq changes.
21 *
22 * Continuity means that when our frequency changes our slope (b); we want to
23 * ensure that: f(t) == f'(t), which gives: a + b*t == a' + b'*t.
24 *
25 * Without an offset (a) the above would not be possible.
26 *
27 * See the comment near cycles_2_ns() for details on how we compute (b).
28 */
29struct cyc2ns_data {
30 u32 cyc2ns_mul;
31 u32 cyc2ns_shift;
32 u64 cyc2ns_offset;
33}; /* 16 bytes */
34
35extern void cyc2ns_read_begin(struct cyc2ns_data *);
36extern void cyc2ns_read_end(void);
37
38#endif /* _ASM_X86_TIMER_H */
39

source code of linux/arch/x86/include/asm/timer.h