xref: /openbmc/u-boot/lib/time.c (revision cbcbf71bf238abd6daf13116b9a209c8fc98ae64)
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  #else
40  extern unsigned long __weak timer_read_counter(void);
41  #endif
42  
43  #ifdef CONFIG_TIMER
44  ulong notrace get_tbclk(void)
45  {
46  	if (!gd->timer) {
47  #ifdef CONFIG_TIMER_EARLY
48  		return timer_early_get_rate();
49  #else
50  		int ret;
51  
52  		ret = dm_timer_init();
53  		if (ret)
54  			return ret;
55  #endif
56  	}
57  
58  	return timer_get_rate(gd->timer);
59  }
60  
61  uint64_t notrace get_ticks(void)
62  {
63  	u64 count;
64  	int ret;
65  
66  	if (!gd->timer) {
67  #ifdef CONFIG_TIMER_EARLY
68  		return timer_early_get_count();
69  #else
70  		int ret;
71  
72  		ret = dm_timer_init();
73  		if (ret)
74  			return ret;
75  #endif
76  	}
77  
78  	ret = timer_get_count(gd->timer, &count);
79  	if (ret)
80  		return ret;
81  
82  	return count;
83  }
84  
85  #else /* !CONFIG_TIMER */
86  
87  uint64_t __weak notrace get_ticks(void)
88  {
89  	unsigned long now = timer_read_counter();
90  
91  	/* increment tbu if tbl has rolled over */
92  	if (now < gd->timebase_l)
93  		gd->timebase_h++;
94  	gd->timebase_l = now;
95  	return ((uint64_t)gd->timebase_h << 32) | gd->timebase_l;
96  }
97  
98  #endif /* CONFIG_TIMER */
99  
100  /* Returns time in milliseconds */
101  static uint64_t notrace tick_to_time(uint64_t tick)
102  {
103  	ulong div = get_tbclk();
104  
105  	tick *= CONFIG_SYS_HZ;
106  	do_div(tick, div);
107  	return tick;
108  }
109  
110  int __weak timer_init(void)
111  {
112  	return 0;
113  }
114  
115  /* Returns time in milliseconds */
116  ulong __weak get_timer(ulong base)
117  {
118  	return tick_to_time(get_ticks()) - base;
119  }
120  
121  unsigned long __weak notrace timer_get_us(void)
122  {
123  	return tick_to_time(get_ticks() * 1000);
124  }
125  
126  static uint64_t usec_to_tick(unsigned long usec)
127  {
128  	uint64_t tick = usec;
129  	tick *= get_tbclk();
130  	do_div(tick, 1000000);
131  	return tick;
132  }
133  
134  void __weak __udelay(unsigned long usec)
135  {
136  	uint64_t tmp;
137  
138  	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
139  
140  	while (get_ticks() < tmp+1)	/* loop till event */
141  		 /*NOP*/;
142  }
143  
144  /* ------------------------------------------------------------------------- */
145  
146  void udelay(unsigned long usec)
147  {
148  	ulong kv;
149  
150  	do {
151  		WATCHDOG_RESET();
152  		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
153  		__udelay (kv);
154  		usec -= kv;
155  	} while(usec);
156  }
157