162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */
262306a36Sopenharmony_ci#ifndef _ASM_X86_TIMER_H
362306a36Sopenharmony_ci#define _ASM_X86_TIMER_H
462306a36Sopenharmony_ci#include <linux/pm.h>
562306a36Sopenharmony_ci#include <linux/percpu.h>
662306a36Sopenharmony_ci#include <linux/interrupt.h>
762306a36Sopenharmony_ci#include <linux/math64.h>
862306a36Sopenharmony_ci
962306a36Sopenharmony_ci#define TICK_SIZE (tick_nsec / 1000)
1062306a36Sopenharmony_ci
1162306a36Sopenharmony_ciunsigned long long native_sched_clock(void);
1262306a36Sopenharmony_ciextern void recalibrate_cpu_khz(void);
1362306a36Sopenharmony_ci
1462306a36Sopenharmony_ciextern int no_timer_check;
1562306a36Sopenharmony_ci
1662306a36Sopenharmony_ciextern bool using_native_sched_clock(void);
1762306a36Sopenharmony_ci
1862306a36Sopenharmony_ci/*
1962306a36Sopenharmony_ci * We use the full linear equation: f(x) = a + b*x, in order to allow
2062306a36Sopenharmony_ci * a continuous function in the face of dynamic freq changes.
2162306a36Sopenharmony_ci *
2262306a36Sopenharmony_ci * Continuity means that when our frequency changes our slope (b); we want to
2362306a36Sopenharmony_ci * ensure that: f(t) == f'(t), which gives: a + b*t == a' + b'*t.
2462306a36Sopenharmony_ci *
2562306a36Sopenharmony_ci * Without an offset (a) the above would not be possible.
2662306a36Sopenharmony_ci *
2762306a36Sopenharmony_ci * See the comment near cycles_2_ns() for details on how we compute (b).
2862306a36Sopenharmony_ci */
2962306a36Sopenharmony_cistruct cyc2ns_data {
3062306a36Sopenharmony_ci	u32 cyc2ns_mul;
3162306a36Sopenharmony_ci	u32 cyc2ns_shift;
3262306a36Sopenharmony_ci	u64 cyc2ns_offset;
3362306a36Sopenharmony_ci}; /* 16 bytes */
3462306a36Sopenharmony_ci
3562306a36Sopenharmony_ciextern void cyc2ns_read_begin(struct cyc2ns_data *);
3662306a36Sopenharmony_ciextern void cyc2ns_read_end(void);
3762306a36Sopenharmony_ci
3862306a36Sopenharmony_ci#endif /* _ASM_X86_TIMER_H */
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