xref: /openbmc/u-boot/lib/time.c (revision 0b304a24)
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 #if CONFIG_SYS_HZ != 1000
14 #warning "CONFIG_SYS_HZ must be 1000 and should not be defined by platforms"
15 #endif
16 
17 #ifndef CONFIG_WD_PERIOD
18 # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
19 #endif
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 #ifdef CONFIG_SYS_TIMER_RATE
24 /* Returns tick rate in ticks per second */
25 ulong notrace get_tbclk(void)
26 {
27 	return CONFIG_SYS_TIMER_RATE;
28 }
29 #endif
30 
31 #ifdef CONFIG_SYS_TIMER_COUNTER
32 unsigned long notrace timer_read_counter(void)
33 {
34 #ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
35 	return ~readl(CONFIG_SYS_TIMER_COUNTER);
36 #else
37 	return readl(CONFIG_SYS_TIMER_COUNTER);
38 #endif
39 }
40 #else
41 extern unsigned long __weak timer_read_counter(void);
42 #endif
43 
44 unsigned long long __weak notrace get_ticks(void)
45 {
46 	unsigned long now = timer_read_counter();
47 
48 	/* increment tbu if tbl has rolled over */
49 	if (now < gd->timebase_l)
50 		gd->timebase_h++;
51 	gd->timebase_l = now;
52 	return ((unsigned long long)gd->timebase_h << 32) | gd->timebase_l;
53 }
54 
55 /* Returns time in milliseconds */
56 static unsigned long long notrace tick_to_time(unsigned long long tick)
57 {
58 	ulong div = get_tbclk();
59 
60 	tick *= CONFIG_SYS_HZ;
61 	do_div(tick, div);
62 	return tick;
63 }
64 
65 int __weak timer_init(void)
66 {
67 	return 0;
68 }
69 
70 /* Returns time in milliseconds */
71 ulong __weak get_timer(ulong base)
72 {
73 	return tick_to_time(get_ticks()) - base;
74 }
75 
76 unsigned long __weak notrace timer_get_us(void)
77 {
78 	return tick_to_time(get_ticks() * 1000);
79 }
80 
81 static unsigned long long usec_to_tick(unsigned long usec)
82 {
83 	unsigned long long tick = usec;
84 	tick *= get_tbclk();
85 	do_div(tick, 1000000);
86 	return tick;
87 }
88 
89 void __weak __udelay(unsigned long usec)
90 {
91 	unsigned long long tmp;
92 
93 	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
94 
95 	while (get_ticks() < tmp+1)	/* loop till event */
96 		 /*NOP*/;
97 }
98 
99 /* ------------------------------------------------------------------------- */
100 
101 void udelay(unsigned long usec)
102 {
103 	ulong kv;
104 
105 	do {
106 		WATCHDOG_RESET();
107 		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
108 		__udelay (kv);
109 		usec -= kv;
110 	} while(usec);
111 }
112 
113 void mdelay(unsigned long msec)
114 {
115 	while (msec--)
116 		udelay(1000);
117 }
118