1/* SPDX-License-Identifier: GPL-2.0+ */
2
3#ifndef _TIME_H
4#define _TIME_H
5
6#include <linux/typecheck.h>
7#include <linux/types.h>
8
9ulong get_tbclk(void);
10
11unsigned long get_timer(unsigned long base);
12
13/*
14 * Return the current value of a monotonically increasing microsecond timer.
15 * Granularity may be larger than 1us if hardware does not support this.
16 */
17unsigned long timer_get_us(void);
18uint64_t get_timer_us(uint64_t base);
19
20/**
21 * get_timer_us_long() - Get the number of elapsed microseconds
22 *
23 * This uses 32-bit arithmetic on 32-bit machines, which is enough to handle
24 * delays of over an hour. For 64-bit machines it uses a 64-bit value.
25 *
26 *@base: Base time to consider
27 *Return: elapsed time since @base
28 */
29unsigned long get_timer_us_long(unsigned long base);
30
31/*
32 * timer_test_add_offset()
33 *
34 * Allow tests to add to the time reported through lib/time.c functions
35 * offset: number of milliseconds to advance the system time
36 */
37void timer_test_add_offset(unsigned long offset);
38
39/**
40 * usec_to_tick() - convert microseconds to clock ticks
41 *
42 * @usec:	duration in microseconds
43 * Return:	duration in clock ticks
44 */
45uint64_t usec_to_tick(unsigned long usec);
46
47/*
48 *	These inlines deal with timer wrapping correctly. You are
49 *	strongly encouraged to use them
50 *	1. Because people otherwise forget
51 *	2. Because if the timer wrap changes in future you won't have to
52 *	   alter your driver code.
53 *
54 * time_after(a,b) returns true if the time a is after time b.
55 *
56 * Do this with "<0" and ">=0" to only test the sign of the result. A
57 * good compiler would generate better code (and a really good compiler
58 * wouldn't care). Gcc is currently neither.
59 */
60#define time_after(a,b)		\
61	(typecheck(unsigned long, a) && \
62	 typecheck(unsigned long, b) && \
63	 ((long)((b) - (a)) < 0))
64#define time_before(a,b)	time_after(b,a)
65
66#define time_after_eq(a,b)	\
67	(typecheck(unsigned long, a) && \
68	 typecheck(unsigned long, b) && \
69	 ((long)((a) - (b)) >= 0))
70#define time_before_eq(a,b)	time_after_eq(b,a)
71
72/*
73 * Calculate whether a is in the range of [b, c].
74 */
75#define time_in_range(a,b,c) \
76	(time_after_eq(a,b) && \
77	 time_before_eq(a,c))
78
79/*
80 * Calculate whether a is in the range of [b, c).
81 */
82#define time_in_range_open(a,b,c) \
83	(time_after_eq(a,b) && \
84	 time_before(a,c))
85
86/* Same as above, but does so with platform independent 64bit types.
87 * These must be used when utilizing jiffies_64 (i.e. return value of
88 * get_jiffies_64() */
89#define time_after64(a,b)	\
90	(typecheck(__u64, a) &&	\
91	 typecheck(__u64, b) && \
92	 ((__s64)((b) - (a)) < 0))
93#define time_before64(a,b)	time_after64(b,a)
94
95#define time_after_eq64(a,b)	\
96	(typecheck(__u64, a) && \
97	 typecheck(__u64, b) && \
98	 ((__s64)((a) - (b)) >= 0))
99#define time_before_eq64(a,b)	time_after_eq64(b,a)
100
101#define time_in_range64(a, b, c) \
102	(time_after_eq64(a, b) && \
103	 time_before_eq64(a, c))
104
105/**
106 * usec2ticks() - Convert microseconds to internal ticks
107 *
108 * @usec: Value of microseconds to convert
109 * Return: Corresponding internal ticks value, calculated using get_tbclk()
110 */
111ulong usec2ticks(unsigned long usec);
112
113/**
114 * ticks2usec() - Convert internal ticks to microseconds
115 *
116 * @ticks: Value of ticks to convert
117 * Return: Corresponding microseconds value, calculated using get_tbclk()
118 */
119ulong ticks2usec(unsigned long ticks);
120
121/**
122 * wait_ticks() - waits a given number of ticks
123 *
124 * This is an internal function typically used to implement udelay() and
125 * similar. Normally you should use udelay() or mdelay() instead.
126 *
127 * @ticks: Number of ticks to wait
128 */
129void wait_ticks(unsigned long ticks);
130
131/**
132 * timer_get_us() - Get monotonic microsecond timer
133 *
134 * Return: value of monotonic microsecond timer
135 */
136unsigned long timer_get_us(void);
137
138/**
139 * get_ticks() - Get the current tick value
140 *
141 * This is an internal value used by the timer on the system. Ticks increase
142 * monotonically at the rate given by get_tbclk().
143 *
144 * Return: current tick value
145 */
146uint64_t get_ticks(void);
147
148#endif /* _TIME_H */
149