xref: /openbmc/u-boot/lib/time.c (revision 176bf4ce)
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 <watchdog.h>
10 #include <div64.h>
11 #include <asm/io.h>
12 
13 #ifndef CONFIG_WD_PERIOD
14 # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
15 #endif
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 #ifdef CONFIG_SYS_TIMER_RATE
20 /* Returns tick rate in ticks per second */
21 ulong notrace get_tbclk(void)
22 {
23 	return CONFIG_SYS_TIMER_RATE;
24 }
25 #endif
26 
27 #ifdef CONFIG_SYS_TIMER_COUNTER
28 unsigned long notrace timer_read_counter(void)
29 {
30 #ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
31 	return ~readl(CONFIG_SYS_TIMER_COUNTER);
32 #else
33 	return readl(CONFIG_SYS_TIMER_COUNTER);
34 #endif
35 }
36 #else
37 extern unsigned long __weak timer_read_counter(void);
38 #endif
39 
40 uint64_t __weak notrace get_ticks(void)
41 {
42 	unsigned long now = timer_read_counter();
43 
44 	/* increment tbu if tbl has rolled over */
45 	if (now < gd->timebase_l)
46 		gd->timebase_h++;
47 	gd->timebase_l = now;
48 	return ((uint64_t)gd->timebase_h << 32) | gd->timebase_l;
49 }
50 
51 /* Returns time in milliseconds */
52 static uint64_t notrace tick_to_time(uint64_t tick)
53 {
54 	ulong div = get_tbclk();
55 
56 	tick *= CONFIG_SYS_HZ;
57 	do_div(tick, div);
58 	return tick;
59 }
60 
61 int __weak timer_init(void)
62 {
63 	return 0;
64 }
65 
66 /* Returns time in milliseconds */
67 ulong __weak get_timer(ulong base)
68 {
69 	return tick_to_time(get_ticks()) - base;
70 }
71 
72 unsigned long __weak notrace timer_get_us(void)
73 {
74 	return tick_to_time(get_ticks() * 1000);
75 }
76 
77 static uint64_t usec_to_tick(unsigned long usec)
78 {
79 	uint64_t tick = usec;
80 	tick *= get_tbclk();
81 	do_div(tick, 1000000);
82 	return tick;
83 }
84 
85 void __weak __udelay(unsigned long usec)
86 {
87 	uint64_t tmp;
88 
89 	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
90 
91 	while (get_ticks() < tmp+1)	/* loop till event */
92 		 /*NOP*/;
93 }
94 
95 /* ------------------------------------------------------------------------- */
96 
97 void udelay(unsigned long usec)
98 {
99 	ulong kv;
100 
101 	do {
102 		WATCHDOG_RESET();
103 		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
104 		__udelay (kv);
105 		usec -= kv;
106 	} while(usec);
107 }
108 
109 void mdelay(unsigned long msec)
110 {
111 	while (msec--)
112 		udelay(1000);
113 }
114