xref: /openbmc/u-boot/lib/time.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2000-2009
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <timer.h>
11 #include <watchdog.h>
12 #include <div64.h>
13 #include <asm/io.h>
14 
15 #ifndef CONFIG_WD_PERIOD
16 # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
17 #endif
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 #ifdef CONFIG_SYS_TIMER_RATE
22 /* Returns tick rate in ticks per second */
23 ulong notrace get_tbclk(void)
24 {
25 	return CONFIG_SYS_TIMER_RATE;
26 }
27 #endif
28 
29 #ifdef CONFIG_SYS_TIMER_COUNTER
30 unsigned long notrace timer_read_counter(void)
31 {
32 #ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
33 	return ~readl(CONFIG_SYS_TIMER_COUNTER);
34 #else
35 	return readl(CONFIG_SYS_TIMER_COUNTER);
36 #endif
37 }
38 
39 ulong timer_get_boot_us(void)
40 {
41 	ulong count = timer_read_counter();
42 
43 #if CONFIG_SYS_TIMER_RATE == 1000000
44 	return count;
45 #elif CONFIG_SYS_TIMER_RATE > 1000000
46 	return lldiv(count, CONFIG_SYS_TIMER_RATE / 1000000);
47 #elif defined(CONFIG_SYS_TIMER_RATE)
48 	return (unsigned long long)count * 1000000 / CONFIG_SYS_TIMER_RATE;
49 #else
50 	/* Assume the counter is in microseconds */
51 	return count;
52 #endif
53 }
54 
55 #else
56 extern unsigned long __weak timer_read_counter(void);
57 #endif
58 
59 #ifdef CONFIG_TIMER
60 ulong notrace get_tbclk(void)
61 {
62 	if (!gd->timer) {
63 #ifdef CONFIG_TIMER_EARLY
64 		return timer_early_get_rate();
65 #else
66 		int ret;
67 
68 		ret = dm_timer_init();
69 		if (ret)
70 			return ret;
71 #endif
72 	}
73 
74 	return timer_get_rate(gd->timer);
75 }
76 
77 uint64_t notrace get_ticks(void)
78 {
79 	u64 count;
80 	int ret;
81 
82 	if (!gd->timer) {
83 #ifdef CONFIG_TIMER_EARLY
84 		return timer_early_get_count();
85 #else
86 		int ret;
87 
88 		ret = dm_timer_init();
89 		if (ret)
90 			return ret;
91 #endif
92 	}
93 
94 	ret = timer_get_count(gd->timer, &count);
95 	if (ret)
96 		return ret;
97 
98 	return count;
99 }
100 
101 #else /* !CONFIG_TIMER */
102 
103 uint64_t __weak notrace get_ticks(void)
104 {
105 	unsigned long now = timer_read_counter();
106 
107 	/* increment tbu if tbl has rolled over */
108 	if (now < gd->timebase_l)
109 		gd->timebase_h++;
110 	gd->timebase_l = now;
111 	return ((uint64_t)gd->timebase_h << 32) | gd->timebase_l;
112 }
113 
114 #endif /* CONFIG_TIMER */
115 
116 /* Returns time in milliseconds */
117 static uint64_t notrace tick_to_time(uint64_t tick)
118 {
119 	ulong div = get_tbclk();
120 
121 	tick *= CONFIG_SYS_HZ;
122 	do_div(tick, div);
123 	return tick;
124 }
125 
126 int __weak timer_init(void)
127 {
128 	return 0;
129 }
130 
131 /* Returns time in milliseconds */
132 ulong __weak get_timer(ulong base)
133 {
134 	return tick_to_time(get_ticks()) - base;
135 }
136 
137 unsigned long __weak notrace timer_get_us(void)
138 {
139 	return tick_to_time(get_ticks() * 1000);
140 }
141 
142 static uint64_t usec_to_tick(unsigned long usec)
143 {
144 	uint64_t tick = usec;
145 	tick *= get_tbclk();
146 	do_div(tick, 1000000);
147 	return tick;
148 }
149 
150 void __weak __udelay(unsigned long usec)
151 {
152 	uint64_t tmp;
153 
154 	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
155 
156 	while (get_ticks() < tmp+1)	/* loop till event */
157 		 /*NOP*/;
158 }
159 
160 /* ------------------------------------------------------------------------- */
161 
162 void udelay(unsigned long usec)
163 {
164 	ulong kv;
165 
166 	do {
167 		WATCHDOG_RESET();
168 		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
169 		__udelay (kv);
170 		usec -= kv;
171 	} while(usec);
172 }
173