Commit | Line | Data |
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1da177e4 | 1 | /* |
8c24594d | 2 | * arch/sh/kernel/time_32.c |
1da177e4 LT |
3 | * |
4 | * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka | |
5 | * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> | |
8c24594d | 6 | * Copyright (C) 2002 - 2008 Paul Mundt |
1da177e4 LT |
7 | * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> |
8 | * | |
9 | * Some code taken from i386 version. | |
10 | * Copyright (C) 1991, 1992, 1995 Linus Torvalds | |
11 | */ | |
1da177e4 | 12 | #include <linux/kernel.h> |
36ddf31b | 13 | #include <linux/module.h> |
1da177e4 | 14 | #include <linux/init.h> |
1da177e4 | 15 | #include <linux/profile.h> |
65e5d90d PM |
16 | #include <linux/timex.h> |
17 | #include <linux/sched.h> | |
57be2b48 | 18 | #include <linux/clockchips.h> |
fa43972f | 19 | #include <linux/mc146818rtc.h> /* for rtc_lock */ |
8c24594d | 20 | #include <linux/smp.h> |
36ddf31b | 21 | #include <asm/clock.h> |
1da177e4 | 22 | #include <asm/rtc.h> |
36ddf31b | 23 | #include <asm/timer.h> |
1da177e4 | 24 | #include <asm/kgdb.h> |
1da177e4 | 25 | |
36ddf31b PM |
26 | struct sys_timer *sys_timer; |
27 | ||
28 | /* Move this somewhere more sensible.. */ | |
29 | DEFINE_SPINLOCK(rtc_lock); | |
30 | EXPORT_SYMBOL(rtc_lock); | |
1da177e4 | 31 | |
91550f71 PM |
32 | /* Dummy RTC ops */ |
33 | static void null_rtc_get_time(struct timespec *tv) | |
34 | { | |
35 | tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0); | |
36 | tv->tv_nsec = 0; | |
37 | } | |
38 | ||
39 | static int null_rtc_set_time(const time_t secs) | |
40 | { | |
41 | return 0; | |
42 | } | |
43 | ||
57be2b48 PM |
44 | /* |
45 | * Null high precision timer functions for systems lacking one. | |
46 | */ | |
47 | static cycle_t null_hpt_read(void) | |
48 | { | |
49 | return 0; | |
50 | } | |
51 | ||
91550f71 PM |
52 | void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; |
53 | int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; | |
1da177e4 | 54 | |
45882145 | 55 | #ifndef CONFIG_GENERIC_TIME |
1da177e4 LT |
56 | void do_gettimeofday(struct timeval *tv) |
57 | { | |
e74b5680 | 58 | unsigned long flags; |
1da177e4 LT |
59 | unsigned long seq; |
60 | unsigned long usec, sec; | |
1da177e4 LT |
61 | |
62 | do { | |
e74b5680 PM |
63 | /* |
64 | * Turn off IRQs when grabbing xtime_lock, so that | |
65 | * the sys_timer get_offset code doesn't have to handle it. | |
66 | */ | |
67 | seq = read_seqbegin_irqsave(&xtime_lock, flags); | |
36ddf31b | 68 | usec = get_timer_offset(); |
1da177e4 | 69 | sec = xtime.tv_sec; |
e74b5680 PM |
70 | usec += xtime.tv_nsec / NSEC_PER_USEC; |
71 | } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); | |
1da177e4 LT |
72 | |
73 | while (usec >= 1000000) { | |
74 | usec -= 1000000; | |
75 | sec++; | |
76 | } | |
77 | ||
78 | tv->tv_sec = sec; | |
79 | tv->tv_usec = usec; | |
80 | } | |
1da177e4 LT |
81 | EXPORT_SYMBOL(do_gettimeofday); |
82 | ||
83 | int do_settimeofday(struct timespec *tv) | |
84 | { | |
85 | time_t wtm_sec, sec = tv->tv_sec; | |
86 | long wtm_nsec, nsec = tv->tv_nsec; | |
87 | ||
88 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) | |
89 | return -EINVAL; | |
90 | ||
91 | write_seqlock_irq(&xtime_lock); | |
92 | /* | |
93 | * This is revolting. We need to set "xtime" correctly. However, the | |
94 | * value in this location is the value at the most recent update of | |
95 | * wall time. Discover what correction gettimeofday() would have | |
96 | * made, and then undo it! | |
97 | */ | |
e74b5680 | 98 | nsec -= get_timer_offset() * NSEC_PER_USEC; |
1da177e4 LT |
99 | |
100 | wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); | |
101 | wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); | |
102 | ||
103 | set_normalized_timespec(&xtime, sec, nsec); | |
104 | set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); | |
105 | ||
b149ee22 | 106 | ntp_clear(); |
1da177e4 LT |
107 | write_sequnlock_irq(&xtime_lock); |
108 | clock_was_set(); | |
109 | ||
110 | return 0; | |
111 | } | |
1da177e4 | 112 | EXPORT_SYMBOL(do_settimeofday); |
45882145 | 113 | #endif /* !CONFIG_GENERIC_TIME */ |
1da177e4 | 114 | |
57be2b48 | 115 | #ifndef CONFIG_GENERIC_CLOCKEVENTS |
1da177e4 LT |
116 | /* last time the RTC clock got updated */ |
117 | static long last_rtc_update; | |
118 | ||
119 | /* | |
36ddf31b | 120 | * handle_timer_tick() needs to keep up the real-time clock, |
1da177e4 LT |
121 | * as well as call the "do_timer()" routine every clocktick |
122 | */ | |
35f3c518 | 123 | void handle_timer_tick(void) |
1da177e4 | 124 | { |
35f3c518 PM |
125 | if (current->pid) |
126 | profile_tick(CPU_PROFILING); | |
1da177e4 | 127 | |
960c65e8 PZ |
128 | /* |
129 | * Here we are in the timer irq handler. We just have irqs locally | |
130 | * disabled but we don't know if the timer_bh is running on the other | |
131 | * CPU. We need to avoid to SMP race with it. NOTE: we don' t need | |
132 | * the irq version of write_lock because as just said we have irq | |
133 | * locally disabled. -arca | |
134 | */ | |
135 | write_seqlock(&xtime_lock); | |
136 | do_timer(1); | |
137 | ||
1da177e4 LT |
138 | /* |
139 | * If we have an externally synchronized Linux clock, then update | |
140 | * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be | |
141 | * called as close as possible to 500 ms before the new second starts. | |
142 | */ | |
b149ee22 | 143 | if (ntp_synced() && |
1da177e4 LT |
144 | xtime.tv_sec > last_rtc_update + 660 && |
145 | (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && | |
146 | (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { | |
af514ca7 | 147 | if (rtc_sh_set_time(xtime.tv_sec) == 0) |
1da177e4 LT |
148 | last_rtc_update = xtime.tv_sec; |
149 | else | |
36ddf31b PM |
150 | /* do it again in 60s */ |
151 | last_rtc_update = xtime.tv_sec - 600; | |
1da177e4 | 152 | } |
960c65e8 PZ |
153 | write_sequnlock(&xtime_lock); |
154 | ||
155 | #ifndef CONFIG_SMP | |
156 | update_process_times(user_mode(get_irq_regs())); | |
157 | #endif | |
1da177e4 | 158 | } |
57be2b48 | 159 | #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ |
1da177e4 | 160 | |
3aa770e7 AS |
161 | #ifdef CONFIG_PM |
162 | int timer_suspend(struct sys_device *dev, pm_message_t state) | |
163 | { | |
164 | struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); | |
165 | ||
166 | sys_timer->ops->stop(); | |
167 | ||
168 | return 0; | |
169 | } | |
170 | ||
171 | int timer_resume(struct sys_device *dev) | |
172 | { | |
173 | struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); | |
174 | ||
175 | sys_timer->ops->start(); | |
176 | ||
177 | return 0; | |
178 | } | |
179 | #else | |
180 | #define timer_suspend NULL | |
181 | #define timer_resume NULL | |
182 | #endif | |
183 | ||
36ddf31b | 184 | static struct sysdev_class timer_sysclass = { |
af5ca3f4 | 185 | .name = "timer", |
3aa770e7 AS |
186 | .suspend = timer_suspend, |
187 | .resume = timer_resume, | |
1da177e4 LT |
188 | }; |
189 | ||
57be2b48 | 190 | static int __init timer_init_sysfs(void) |
bd156147 | 191 | { |
57be2b48 PM |
192 | int ret = sysdev_class_register(&timer_sysclass); |
193 | if (ret != 0) | |
194 | return ret; | |
bd156147 | 195 | |
57be2b48 PM |
196 | sys_timer->dev.cls = &timer_sysclass; |
197 | return sysdev_register(&sys_timer->dev); | |
bd156147 | 198 | } |
57be2b48 | 199 | device_initcall(timer_init_sysfs); |
bd156147 | 200 | |
57be2b48 | 201 | void (*board_time_init)(void); |
bd156147 PM |
202 | |
203 | /* | |
57be2b48 | 204 | * Shamelessly based on the MIPS and Sparc64 work. |
bd156147 | 205 | */ |
57be2b48 PM |
206 | static unsigned long timer_ticks_per_nsec_quotient __read_mostly; |
207 | unsigned long sh_hpt_frequency = 0; | |
208 | ||
209 | #define NSEC_PER_CYC_SHIFT 10 | |
210 | ||
4c1cfab1 | 211 | static struct clocksource clocksource_sh = { |
57be2b48 PM |
212 | .name = "SuperH", |
213 | .rating = 200, | |
214 | .mask = CLOCKSOURCE_MASK(32), | |
215 | .read = null_hpt_read, | |
216 | .shift = 16, | |
217 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
218 | }; | |
bd156147 | 219 | |
57be2b48 | 220 | static void __init init_sh_clocksource(void) |
bd156147 | 221 | { |
57be2b48 PM |
222 | if (!sh_hpt_frequency || clocksource_sh.read == null_hpt_read) |
223 | return; | |
bd156147 | 224 | |
57be2b48 PM |
225 | clocksource_sh.mult = clocksource_hz2mult(sh_hpt_frequency, |
226 | clocksource_sh.shift); | |
bd156147 | 227 | |
57be2b48 PM |
228 | timer_ticks_per_nsec_quotient = |
229 | clocksource_hz2mult(sh_hpt_frequency, NSEC_PER_CYC_SHIFT); | |
bd156147 | 230 | |
57be2b48 | 231 | clocksource_register(&clocksource_sh); |
bd156147 | 232 | } |
bd156147 | 233 | |
57be2b48 PM |
234 | #ifdef CONFIG_GENERIC_TIME |
235 | unsigned long long sched_clock(void) | |
bd156147 | 236 | { |
57be2b48 PM |
237 | unsigned long long ticks = clocksource_sh.read(); |
238 | return (ticks * timer_ticks_per_nsec_quotient) >> NSEC_PER_CYC_SHIFT; | |
bd156147 | 239 | } |
bd156147 PM |
240 | #endif |
241 | ||
1da177e4 LT |
242 | void __init time_init(void) |
243 | { | |
1da177e4 LT |
244 | if (board_time_init) |
245 | board_time_init(); | |
246 | ||
36ddf31b | 247 | clk_init(); |
1da177e4 | 248 | |
91550f71 PM |
249 | rtc_sh_get_time(&xtime); |
250 | set_normalized_timespec(&wall_to_monotonic, | |
251 | -xtime.tv_sec, -xtime.tv_nsec); | |
1da177e4 | 252 | |
53c01d2d PM |
253 | #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST |
254 | local_timer_setup(smp_processor_id()); | |
255 | #endif | |
256 | ||
1da177e4 | 257 | /* |
36ddf31b PM |
258 | * Find the timer to use as the system timer, it will be |
259 | * initialized for us. | |
1da177e4 | 260 | */ |
36ddf31b PM |
261 | sys_timer = get_sys_timer(); |
262 | printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); | |
1da177e4 | 263 | |
8c24594d | 264 | |
57be2b48 PM |
265 | if (sys_timer->ops->read) |
266 | clocksource_sh.read = sys_timer->ops->read; | |
267 | ||
268 | init_sh_clocksource(); | |
269 | ||
270 | if (sh_hpt_frequency) | |
271 | printk("Using %lu.%03lu MHz high precision timer.\n", | |
272 | ((sh_hpt_frequency + 500) / 1000) / 1000, | |
273 | ((sh_hpt_frequency + 500) / 1000) % 1000); | |
bd156147 | 274 | |
1da177e4 | 275 | } |