Commit | Line | Data |
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1da177e4 LT |
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> | |
57be2b48 | 6 | * Copyright (C) 2002 - 2007 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> |
36ddf31b | 19 | #include <asm/clock.h> |
1da177e4 | 20 | #include <asm/rtc.h> |
36ddf31b | 21 | #include <asm/timer.h> |
1da177e4 | 22 | #include <asm/kgdb.h> |
1da177e4 | 23 | |
36ddf31b PM |
24 | struct sys_timer *sys_timer; |
25 | ||
26 | /* Move this somewhere more sensible.. */ | |
27 | DEFINE_SPINLOCK(rtc_lock); | |
28 | EXPORT_SYMBOL(rtc_lock); | |
1da177e4 | 29 | |
91550f71 PM |
30 | /* Dummy RTC ops */ |
31 | static void null_rtc_get_time(struct timespec *tv) | |
32 | { | |
33 | tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0); | |
34 | tv->tv_nsec = 0; | |
35 | } | |
36 | ||
37 | static int null_rtc_set_time(const time_t secs) | |
38 | { | |
39 | return 0; | |
40 | } | |
41 | ||
57be2b48 PM |
42 | /* |
43 | * Null high precision timer functions for systems lacking one. | |
44 | */ | |
45 | static cycle_t null_hpt_read(void) | |
46 | { | |
47 | return 0; | |
48 | } | |
49 | ||
91550f71 PM |
50 | void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; |
51 | int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; | |
1da177e4 | 52 | |
45882145 | 53 | #ifndef CONFIG_GENERIC_TIME |
1da177e4 LT |
54 | void do_gettimeofday(struct timeval *tv) |
55 | { | |
e74b5680 | 56 | unsigned long flags; |
1da177e4 LT |
57 | unsigned long seq; |
58 | unsigned long usec, sec; | |
1da177e4 LT |
59 | |
60 | do { | |
e74b5680 PM |
61 | /* |
62 | * Turn off IRQs when grabbing xtime_lock, so that | |
63 | * the sys_timer get_offset code doesn't have to handle it. | |
64 | */ | |
65 | seq = read_seqbegin_irqsave(&xtime_lock, flags); | |
36ddf31b | 66 | usec = get_timer_offset(); |
1da177e4 | 67 | sec = xtime.tv_sec; |
e74b5680 PM |
68 | usec += xtime.tv_nsec / NSEC_PER_USEC; |
69 | } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); | |
1da177e4 LT |
70 | |
71 | while (usec >= 1000000) { | |
72 | usec -= 1000000; | |
73 | sec++; | |
74 | } | |
75 | ||
76 | tv->tv_sec = sec; | |
77 | tv->tv_usec = usec; | |
78 | } | |
1da177e4 LT |
79 | EXPORT_SYMBOL(do_gettimeofday); |
80 | ||
81 | int do_settimeofday(struct timespec *tv) | |
82 | { | |
83 | time_t wtm_sec, sec = tv->tv_sec; | |
84 | long wtm_nsec, nsec = tv->tv_nsec; | |
85 | ||
86 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) | |
87 | return -EINVAL; | |
88 | ||
89 | write_seqlock_irq(&xtime_lock); | |
90 | /* | |
91 | * This is revolting. We need to set "xtime" correctly. However, the | |
92 | * value in this location is the value at the most recent update of | |
93 | * wall time. Discover what correction gettimeofday() would have | |
94 | * made, and then undo it! | |
95 | */ | |
e74b5680 | 96 | nsec -= get_timer_offset() * NSEC_PER_USEC; |
1da177e4 LT |
97 | |
98 | wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); | |
99 | wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); | |
100 | ||
101 | set_normalized_timespec(&xtime, sec, nsec); | |
102 | set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); | |
103 | ||
b149ee22 | 104 | ntp_clear(); |
1da177e4 LT |
105 | write_sequnlock_irq(&xtime_lock); |
106 | clock_was_set(); | |
107 | ||
108 | return 0; | |
109 | } | |
1da177e4 | 110 | EXPORT_SYMBOL(do_settimeofday); |
45882145 | 111 | #endif /* !CONFIG_GENERIC_TIME */ |
1da177e4 | 112 | |
57be2b48 | 113 | #ifndef CONFIG_GENERIC_CLOCKEVENTS |
1da177e4 LT |
114 | /* last time the RTC clock got updated */ |
115 | static long last_rtc_update; | |
116 | ||
117 | /* | |
36ddf31b | 118 | * handle_timer_tick() needs to keep up the real-time clock, |
1da177e4 LT |
119 | * as well as call the "do_timer()" routine every clocktick |
120 | */ | |
35f3c518 | 121 | void handle_timer_tick(void) |
1da177e4 | 122 | { |
35f3c518 PM |
123 | if (current->pid) |
124 | profile_tick(CPU_PROFILING); | |
1da177e4 LT |
125 | |
126 | #ifdef CONFIG_HEARTBEAT | |
127 | if (sh_mv.mv_heartbeat != NULL) | |
128 | sh_mv.mv_heartbeat(); | |
129 | #endif | |
130 | ||
960c65e8 PZ |
131 | /* |
132 | * Here we are in the timer irq handler. We just have irqs locally | |
133 | * disabled but we don't know if the timer_bh is running on the other | |
134 | * CPU. We need to avoid to SMP race with it. NOTE: we don' t need | |
135 | * the irq version of write_lock because as just said we have irq | |
136 | * locally disabled. -arca | |
137 | */ | |
138 | write_seqlock(&xtime_lock); | |
139 | do_timer(1); | |
140 | ||
1da177e4 LT |
141 | /* |
142 | * If we have an externally synchronized Linux clock, then update | |
143 | * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be | |
144 | * called as close as possible to 500 ms before the new second starts. | |
145 | */ | |
b149ee22 | 146 | if (ntp_synced() && |
1da177e4 LT |
147 | xtime.tv_sec > last_rtc_update + 660 && |
148 | (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && | |
149 | (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { | |
af514ca7 | 150 | if (rtc_sh_set_time(xtime.tv_sec) == 0) |
1da177e4 LT |
151 | last_rtc_update = xtime.tv_sec; |
152 | else | |
36ddf31b PM |
153 | /* do it again in 60s */ |
154 | last_rtc_update = xtime.tv_sec - 600; | |
1da177e4 | 155 | } |
960c65e8 PZ |
156 | write_sequnlock(&xtime_lock); |
157 | ||
158 | #ifndef CONFIG_SMP | |
159 | update_process_times(user_mode(get_irq_regs())); | |
160 | #endif | |
1da177e4 | 161 | } |
57be2b48 | 162 | #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ |
1da177e4 | 163 | |
3aa770e7 AS |
164 | #ifdef CONFIG_PM |
165 | int timer_suspend(struct sys_device *dev, pm_message_t state) | |
166 | { | |
167 | struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); | |
168 | ||
169 | sys_timer->ops->stop(); | |
170 | ||
171 | return 0; | |
172 | } | |
173 | ||
174 | int timer_resume(struct sys_device *dev) | |
175 | { | |
176 | struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); | |
177 | ||
178 | sys_timer->ops->start(); | |
179 | ||
180 | return 0; | |
181 | } | |
182 | #else | |
183 | #define timer_suspend NULL | |
184 | #define timer_resume NULL | |
185 | #endif | |
186 | ||
36ddf31b | 187 | static struct sysdev_class timer_sysclass = { |
af5ca3f4 | 188 | .name = "timer", |
3aa770e7 AS |
189 | .suspend = timer_suspend, |
190 | .resume = timer_resume, | |
1da177e4 LT |
191 | }; |
192 | ||
57be2b48 | 193 | static int __init timer_init_sysfs(void) |
bd156147 | 194 | { |
57be2b48 PM |
195 | int ret = sysdev_class_register(&timer_sysclass); |
196 | if (ret != 0) | |
197 | return ret; | |
bd156147 | 198 | |
57be2b48 PM |
199 | sys_timer->dev.cls = &timer_sysclass; |
200 | return sysdev_register(&sys_timer->dev); | |
bd156147 | 201 | } |
57be2b48 | 202 | device_initcall(timer_init_sysfs); |
bd156147 | 203 | |
57be2b48 | 204 | void (*board_time_init)(void); |
bd156147 PM |
205 | |
206 | /* | |
57be2b48 | 207 | * Shamelessly based on the MIPS and Sparc64 work. |
bd156147 | 208 | */ |
57be2b48 PM |
209 | static unsigned long timer_ticks_per_nsec_quotient __read_mostly; |
210 | unsigned long sh_hpt_frequency = 0; | |
211 | ||
212 | #define NSEC_PER_CYC_SHIFT 10 | |
213 | ||
4c1cfab1 | 214 | static struct clocksource clocksource_sh = { |
57be2b48 PM |
215 | .name = "SuperH", |
216 | .rating = 200, | |
217 | .mask = CLOCKSOURCE_MASK(32), | |
218 | .read = null_hpt_read, | |
219 | .shift = 16, | |
220 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
221 | }; | |
bd156147 | 222 | |
57be2b48 | 223 | static void __init init_sh_clocksource(void) |
bd156147 | 224 | { |
57be2b48 PM |
225 | if (!sh_hpt_frequency || clocksource_sh.read == null_hpt_read) |
226 | return; | |
bd156147 | 227 | |
57be2b48 PM |
228 | clocksource_sh.mult = clocksource_hz2mult(sh_hpt_frequency, |
229 | clocksource_sh.shift); | |
bd156147 | 230 | |
57be2b48 PM |
231 | timer_ticks_per_nsec_quotient = |
232 | clocksource_hz2mult(sh_hpt_frequency, NSEC_PER_CYC_SHIFT); | |
bd156147 | 233 | |
57be2b48 | 234 | clocksource_register(&clocksource_sh); |
bd156147 | 235 | } |
bd156147 | 236 | |
57be2b48 PM |
237 | #ifdef CONFIG_GENERIC_TIME |
238 | unsigned long long sched_clock(void) | |
bd156147 | 239 | { |
57be2b48 PM |
240 | unsigned long long ticks = clocksource_sh.read(); |
241 | return (ticks * timer_ticks_per_nsec_quotient) >> NSEC_PER_CYC_SHIFT; | |
bd156147 | 242 | } |
bd156147 PM |
243 | #endif |
244 | ||
1da177e4 LT |
245 | void __init time_init(void) |
246 | { | |
1da177e4 LT |
247 | if (board_time_init) |
248 | board_time_init(); | |
249 | ||
36ddf31b | 250 | clk_init(); |
1da177e4 | 251 | |
91550f71 PM |
252 | rtc_sh_get_time(&xtime); |
253 | set_normalized_timespec(&wall_to_monotonic, | |
254 | -xtime.tv_sec, -xtime.tv_nsec); | |
1da177e4 | 255 | |
1da177e4 | 256 | /* |
36ddf31b PM |
257 | * Find the timer to use as the system timer, it will be |
258 | * initialized for us. | |
1da177e4 | 259 | */ |
36ddf31b PM |
260 | sys_timer = get_sys_timer(); |
261 | printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); | |
1da177e4 | 262 | |
57be2b48 PM |
263 | if (sys_timer->ops->read) |
264 | clocksource_sh.read = sys_timer->ops->read; | |
265 | ||
266 | init_sh_clocksource(); | |
267 | ||
268 | if (sh_hpt_frequency) | |
269 | printk("Using %lu.%03lu MHz high precision timer.\n", | |
270 | ((sh_hpt_frequency + 500) / 1000) / 1000, | |
271 | ((sh_hpt_frequency + 500) / 1000) % 1000); | |
bd156147 | 272 | |
1da177e4 LT |
273 | #if defined(CONFIG_SH_KGDB) |
274 | /* | |
275 | * Set up kgdb as requested. We do it here because the serial | |
276 | * init uses the timer vars we just set up for figuring baud. | |
277 | */ | |
278 | kgdb_init(); | |
279 | #endif | |
280 | } |