xref: /openbmc/u-boot/lib/time.c (revision 9eea5016)
1 /*
2  * (C) Copyright 2000-2009
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <timer.h>
12 #include <watchdog.h>
13 #include <div64.h>
14 #include <asm/io.h>
15 
16 #ifndef CONFIG_WD_PERIOD
17 # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
18 #endif
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 #ifdef CONFIG_SYS_TIMER_RATE
23 /* Returns tick rate in ticks per second */
24 ulong notrace get_tbclk(void)
25 {
26 	return CONFIG_SYS_TIMER_RATE;
27 }
28 #endif
29 
30 #ifdef CONFIG_SYS_TIMER_COUNTER
31 unsigned long notrace timer_read_counter(void)
32 {
33 #ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
34 	return ~readl(CONFIG_SYS_TIMER_COUNTER);
35 #else
36 	return readl(CONFIG_SYS_TIMER_COUNTER);
37 #endif
38 }
39 
40 ulong timer_get_boot_us(void)
41 {
42 	ulong count = timer_read_counter();
43 
44 #if CONFIG_SYS_TIMER_RATE == 1000000
45 	return count;
46 #elif CONFIG_SYS_TIMER_RATE > 1000000
47 	return lldiv(count, CONFIG_SYS_TIMER_RATE / 1000000);
48 #elif defined(CONFIG_SYS_TIMER_RATE)
49 	return (unsigned long long)count * 1000000 / CONFIG_SYS_TIMER_RATE;
50 #else
51 	/* Assume the counter is in microseconds */
52 	return count;
53 #endif
54 }
55 
56 #else
57 extern unsigned long __weak timer_read_counter(void);
58 #endif
59 
60 #ifdef CONFIG_TIMER
61 ulong notrace get_tbclk(void)
62 {
63 	if (!gd->timer) {
64 #ifdef CONFIG_TIMER_EARLY
65 		return timer_early_get_rate();
66 #else
67 		int ret;
68 
69 		ret = dm_timer_init();
70 		if (ret)
71 			return ret;
72 #endif
73 	}
74 
75 	return timer_get_rate(gd->timer);
76 }
77 
78 uint64_t notrace get_ticks(void)
79 {
80 	u64 count;
81 	int ret;
82 
83 	if (!gd->timer) {
84 #ifdef CONFIG_TIMER_EARLY
85 		return timer_early_get_count();
86 #else
87 		int ret;
88 
89 		ret = dm_timer_init();
90 		if (ret)
91 			return ret;
92 #endif
93 	}
94 
95 	ret = timer_get_count(gd->timer, &count);
96 	if (ret)
97 		return ret;
98 
99 	return count;
100 }
101 
102 #else /* !CONFIG_TIMER */
103 
104 uint64_t __weak notrace get_ticks(void)
105 {
106 	unsigned long now = timer_read_counter();
107 
108 	/* increment tbu if tbl has rolled over */
109 	if (now < gd->timebase_l)
110 		gd->timebase_h++;
111 	gd->timebase_l = now;
112 	return ((uint64_t)gd->timebase_h << 32) | gd->timebase_l;
113 }
114 
115 #endif /* CONFIG_TIMER */
116 
117 /* Returns time in milliseconds */
118 static uint64_t notrace tick_to_time(uint64_t tick)
119 {
120 	ulong div = get_tbclk();
121 
122 	tick *= CONFIG_SYS_HZ;
123 	do_div(tick, div);
124 	return tick;
125 }
126 
127 int __weak timer_init(void)
128 {
129 	return 0;
130 }
131 
132 /* Returns time in milliseconds */
133 ulong __weak get_timer(ulong base)
134 {
135 	return tick_to_time(get_ticks()) - base;
136 }
137 
138 unsigned long __weak notrace timer_get_us(void)
139 {
140 	return tick_to_time(get_ticks() * 1000);
141 }
142 
143 static uint64_t usec_to_tick(unsigned long usec)
144 {
145 	uint64_t tick = usec;
146 	tick *= get_tbclk();
147 	do_div(tick, 1000000);
148 	return tick;
149 }
150 
151 void __weak __udelay(unsigned long usec)
152 {
153 	uint64_t tmp;
154 
155 	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
156 
157 	while (get_ticks() < tmp+1)	/* loop till event */
158 		 /*NOP*/;
159 }
160 
161 /* ------------------------------------------------------------------------- */
162 
163 void udelay(unsigned long usec)
164 {
165 	ulong kv;
166 
167 	do {
168 		WATCHDOG_RESET();
169 		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
170 		__udelay (kv);
171 		usec -= kv;
172 	} while(usec);
173 }
174