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
9 ulong get_tbclk(void);
10
11 unsigned 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 */
17 unsigned long timer_get_us(void);
18 uint64_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 */
29 unsigned 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 */
37 void timer_test_add_offset(unsigned long offset);
38
39 #ifdef CONFIG_SANDBOX
40 /**
41 * timer_test_get_offset()
42 *
43 * Get the total offset currently being added the time
44 *
45 * Return:: number of milliseconds the system time has been advanced
46 */
47 ulong timer_test_get_offset(void);
48 #else
timer_test_get_offset(void)49 static inline ulong timer_test_get_offset(void) { return 0; }
50 #endif
51
52 /**
53 * usec_to_tick() - convert microseconds to clock ticks
54 *
55 * @usec: duration in microseconds
56 * Return: duration in clock ticks
57 */
58 uint64_t usec_to_tick(unsigned long usec);
59
60 /*
61 * These inlines deal with timer wrapping correctly. You are
62 * strongly encouraged to use them
63 * 1. Because people otherwise forget
64 * 2. Because if the timer wrap changes in future you won't have to
65 * alter your driver code.
66 *
67 * time_after(a,b) returns true if the time a is after time b.
68 *
69 * Do this with "<0" and ">=0" to only test the sign of the result. A
70 * good compiler would generate better code (and a really good compiler
71 * wouldn't care). Gcc is currently neither.
72 */
73 #define time_after(a,b) \
74 (typecheck(unsigned long, a) && \
75 typecheck(unsigned long, b) && \
76 ((long)((b) - (a)) < 0))
77 #define time_before(a,b) time_after(b,a)
78
79 #define time_after_eq(a,b) \
80 (typecheck(unsigned long, a) && \
81 typecheck(unsigned long, b) && \
82 ((long)((a) - (b)) >= 0))
83 #define time_before_eq(a,b) time_after_eq(b,a)
84
85 /*
86 * Calculate whether a is in the range of [b, c].
87 */
88 #define time_in_range(a,b,c) \
89 (time_after_eq(a,b) && \
90 time_before_eq(a,c))
91
92 /*
93 * Calculate whether a is in the range of [b, c).
94 */
95 #define time_in_range_open(a,b,c) \
96 (time_after_eq(a,b) && \
97 time_before(a,c))
98
99 /* Same as above, but does so with platform independent 64bit types.
100 * These must be used when utilizing jiffies_64 (i.e. return value of
101 * get_jiffies_64() */
102 #define time_after64(a,b) \
103 (typecheck(__u64, a) && \
104 typecheck(__u64, b) && \
105 ((__s64)((b) - (a)) < 0))
106 #define time_before64(a,b) time_after64(b,a)
107
108 #define time_after_eq64(a,b) \
109 (typecheck(__u64, a) && \
110 typecheck(__u64, b) && \
111 ((__s64)((a) - (b)) >= 0))
112 #define time_before_eq64(a,b) time_after_eq64(b,a)
113
114 #define time_in_range64(a, b, c) \
115 (time_after_eq64(a, b) && \
116 time_before_eq64(a, c))
117
118 /**
119 * usec2ticks() - Convert microseconds to internal ticks
120 *
121 * @usec: Value of microseconds to convert
122 * Return: Corresponding internal ticks value, calculated using get_tbclk()
123 */
124 ulong usec2ticks(unsigned long usec);
125
126 /**
127 * ticks2usec() - Convert internal ticks to microseconds
128 *
129 * @ticks: Value of ticks to convert
130 * Return: Corresponding microseconds value, calculated using get_tbclk()
131 */
132 ulong ticks2usec(unsigned long ticks);
133
134 /**
135 * wait_ticks() - waits a given number of ticks
136 *
137 * This is an internal function typically used to implement udelay() and
138 * similar. Normally you should use udelay() or mdelay() instead.
139 *
140 * @ticks: Number of ticks to wait
141 */
142 void wait_ticks(unsigned long ticks);
143
144 /**
145 * timer_get_us() - Get monotonic microsecond timer
146 *
147 * Return: value of monotonic microsecond timer
148 */
149 unsigned long timer_get_us(void);
150
151 /**
152 * get_ticks() - Get the current tick value
153 *
154 * This is an internal value used by the timer on the system. Ticks increase
155 * monotonically at the rate given by get_tbclk().
156 *
157 * Return: current tick value
158 */
159 uint64_t get_ticks(void);
160
161 #endif /* _TIME_H */
162