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 | |
11 | unsigned long long native_sched_clock(void); |
12 | extern void recalibrate_cpu_khz(void); |
13 | |
14 | extern int no_timer_check; |
15 | |
16 | extern 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 | */ |
29 | struct cyc2ns_data { |
30 | u32 cyc2ns_mul; |
31 | u32 cyc2ns_shift; |
32 | u64 cyc2ns_offset; |
33 | }; /* 16 bytes */ |
34 | |
35 | extern void cyc2ns_read_begin(struct cyc2ns_data *); |
36 | extern void cyc2ns_read_end(void); |
37 | |
38 | #endif /* _ASM_X86_TIMER_H */ |
39 | |