xref: /linux/arch/sh/kernel/time.c (revision f19900b2e608b604777a74d6d711bbf744657756)
1 /*
2  *  arch/sh/kernel/time.c
3  *
4  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
5  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
6  *  Copyright (C) 2002 - 2009  Paul Mundt
7  *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License.  See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/profile.h>
17 #include <linux/timex.h>
18 #include <linux/sched.h>
19 #include <linux/clockchips.h>
20 #include <linux/platform_device.h>
21 #include <linux/smp.h>
22 #include <linux/rtc.h>
23 #include <asm/clock.h>
24 #include <asm/rtc.h>
25 #include <asm/timer.h>
26 
27 struct sys_timer *sys_timer;
28 
29 /* Dummy RTC ops */
30 static void null_rtc_get_time(struct timespec *tv)
31 {
32 	tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);
33 	tv->tv_nsec = 0;
34 }
35 
36 static int null_rtc_set_time(const time_t secs)
37 {
38 	return 0;
39 }
40 
41 void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;
42 int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time;
43 
44 #ifdef CONFIG_GENERIC_CMOS_UPDATE
45 unsigned long read_persistent_clock(void)
46 {
47 	struct timespec tv;
48 	rtc_sh_get_time(&tv);
49 	return tv.tv_sec;
50 }
51 
52 int update_persistent_clock(struct timespec now)
53 {
54 	return rtc_sh_set_time(now.tv_sec);
55 }
56 #endif
57 
58 unsigned int get_rtc_time(struct rtc_time *tm)
59 {
60 	if (rtc_sh_get_time != null_rtc_get_time) {
61 		struct timespec tv;
62 
63 		rtc_sh_get_time(&tv);
64 		rtc_time_to_tm(tv.tv_sec, tm);
65 	}
66 
67 	return RTC_24H;
68 }
69 EXPORT_SYMBOL(get_rtc_time);
70 
71 int set_rtc_time(struct rtc_time *tm)
72 {
73 	unsigned long secs;
74 
75 	rtc_tm_to_time(tm, &secs);
76 	return rtc_sh_set_time(secs);
77 }
78 EXPORT_SYMBOL(set_rtc_time);
79 
80 static int __init rtc_generic_init(void)
81 {
82 	struct platform_device *pdev;
83 
84 	if (rtc_sh_get_time == null_rtc_get_time)
85 		return -ENODEV;
86 
87 	pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0);
88 	if (IS_ERR(pdev))
89 		return PTR_ERR(pdev);
90 
91 	return 0;
92 }
93 module_init(rtc_generic_init);
94 
95 void (*board_time_init)(void);
96 
97 struct clocksource clocksource_sh = {
98 	.name		= "SuperH",
99 };
100 
101 unsigned long long sched_clock(void)
102 {
103 	unsigned long long cycles;
104 
105 	/* jiffies based sched_clock if no clocksource is installed */
106 	if (!clocksource_sh.rating)
107 		return (jiffies_64 - INITIAL_JIFFIES) * (NSEC_PER_SEC / HZ);
108 
109 	cycles = clocksource_sh.read(&clocksource_sh);
110 	return cyc2ns(&clocksource_sh, cycles);
111 }
112 
113 static void __init sh_late_time_init(void)
114 {
115 	/*
116 	 * Make sure all compiled-in early timers register themselves.
117 	 * Run probe() for one "earlytimer" device.
118 	 */
119 	early_platform_driver_register_all("earlytimer");
120 	if (early_platform_driver_probe("earlytimer", 1, 0))
121 		return;
122 
123 	/*
124 	 * Find the timer to use as the system timer, it will be
125 	 * initialized for us.
126 	 */
127 	sys_timer = get_sys_timer();
128 	if (unlikely(!sys_timer))
129 		panic("System timer missing.\n");
130 
131 	printk(KERN_INFO "Using %s for system timer\n", sys_timer->name);
132 }
133 
134 void __init time_init(void)
135 {
136 	if (board_time_init)
137 		board_time_init();
138 
139 	clk_init();
140 
141 	rtc_sh_get_time(&xtime);
142 	set_normalized_timespec(&wall_to_monotonic,
143 				-xtime.tv_sec, -xtime.tv_nsec);
144 
145 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
146 	local_timer_setup(smp_processor_id());
147 #endif
148 
149 	late_time_init = sh_late_time_init;
150 }
151