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-rw-r--r--arch/sh/kernel/time.c172
1 files changed, 55 insertions, 117 deletions
diff --git a/arch/sh/kernel/time.c b/arch/sh/kernel/time.c
index d47e775962e9..a3a67d151e52 100644
--- a/arch/sh/kernel/time.c
+++ b/arch/sh/kernel/time.c
@@ -3,7 +3,7 @@
3 * 3 *
4 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka 4 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
5 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> 5 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
6 * Copyright (C) 2002 - 2006 Paul Mundt 6 * Copyright (C) 2002 - 2007 Paul Mundt
7 * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> 7 * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org>
8 * 8 *
9 * Some code taken from i386 version. 9 * Some code taken from i386 version.
@@ -15,6 +15,7 @@
15#include <linux/profile.h> 15#include <linux/profile.h>
16#include <linux/timex.h> 16#include <linux/timex.h>
17#include <linux/sched.h> 17#include <linux/sched.h>
18#include <linux/clockchips.h>
18#include <asm/clock.h> 19#include <asm/clock.h>
19#include <asm/rtc.h> 20#include <asm/rtc.h>
20#include <asm/timer.h> 21#include <asm/timer.h>
@@ -38,6 +39,14 @@ static int null_rtc_set_time(const time_t secs)
38 return 0; 39 return 0;
39} 40}
40 41
42/*
43 * Null high precision timer functions for systems lacking one.
44 */
45static cycle_t null_hpt_read(void)
46{
47 return 0;
48}
49
41void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; 50void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;
42int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; 51int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time;
43 52
@@ -101,6 +110,7 @@ int do_settimeofday(struct timespec *tv)
101EXPORT_SYMBOL(do_settimeofday); 110EXPORT_SYMBOL(do_settimeofday);
102#endif /* !CONFIG_GENERIC_TIME */ 111#endif /* !CONFIG_GENERIC_TIME */
103 112
113#ifndef CONFIG_GENERIC_CLOCKEVENTS
104/* last time the RTC clock got updated */ 114/* last time the RTC clock got updated */
105static long last_rtc_update; 115static long last_rtc_update;
106 116
@@ -138,6 +148,7 @@ void handle_timer_tick(void)
138 last_rtc_update = xtime.tv_sec - 600; 148 last_rtc_update = xtime.tv_sec - 600;
139 } 149 }
140} 150}
151#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
141 152
142#ifdef CONFIG_PM 153#ifdef CONFIG_PM
143int timer_suspend(struct sys_device *dev, pm_message_t state) 154int timer_suspend(struct sys_device *dev, pm_message_t state)
@@ -168,136 +179,58 @@ static struct sysdev_class timer_sysclass = {
168 .resume = timer_resume, 179 .resume = timer_resume,
169}; 180};
170 181
171#ifdef CONFIG_NO_IDLE_HZ 182static int __init timer_init_sysfs(void)
172static int timer_dyn_tick_enable(void)
173{ 183{
174 struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick; 184 int ret = sysdev_class_register(&timer_sysclass);
175 unsigned long flags; 185 if (ret != 0)
176 int ret = -ENODEV; 186 return ret;
177
178 if (dyn_tick) {
179 spin_lock_irqsave(&dyn_tick->lock, flags);
180 ret = 0;
181 if (!(dyn_tick->state & DYN_TICK_ENABLED)) {
182 ret = dyn_tick->enable();
183
184 if (ret == 0)
185 dyn_tick->state |= DYN_TICK_ENABLED;
186 }
187 spin_unlock_irqrestore(&dyn_tick->lock, flags);
188 }
189 187
190 return ret; 188 sys_timer->dev.cls = &timer_sysclass;
189 return sysdev_register(&sys_timer->dev);
191} 190}
191device_initcall(timer_init_sysfs);
192 192
193static int timer_dyn_tick_disable(void) 193void (*board_time_init)(void);
194{
195 struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick;
196 unsigned long flags;
197 int ret = -ENODEV;
198
199 if (dyn_tick) {
200 spin_lock_irqsave(&dyn_tick->lock, flags);
201 ret = 0;
202 if (dyn_tick->state & DYN_TICK_ENABLED) {
203 ret = dyn_tick->disable();
204
205 if (ret == 0)
206 dyn_tick->state &= ~DYN_TICK_ENABLED;
207 }
208 spin_unlock_irqrestore(&dyn_tick->lock, flags);
209 }
210
211 return ret;
212}
213 194
214/* 195/*
215 * Reprogram the system timer for at least the calculated time interval. 196 * Shamelessly based on the MIPS and Sparc64 work.
216 * This function should be called from the idle thread with IRQs disabled,
217 * immediately before sleeping.
218 */ 197 */
219void timer_dyn_reprogram(void) 198static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
220{ 199unsigned long sh_hpt_frequency = 0;
221 struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick; 200
222 unsigned long next, seq, flags; 201#define NSEC_PER_CYC_SHIFT 10
223 202
224 if (!dyn_tick) 203struct clocksource clocksource_sh = {
225 return; 204 .name = "SuperH",
226 205 .rating = 200,
227 spin_lock_irqsave(&dyn_tick->lock, flags); 206 .mask = CLOCKSOURCE_MASK(32),
228 if (dyn_tick->state & DYN_TICK_ENABLED) { 207 .read = null_hpt_read,
229 next = next_timer_interrupt(); 208 .shift = 16,
230 do { 209 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
231 seq = read_seqbegin(&xtime_lock); 210};
232 dyn_tick->reprogram(next - jiffies);
233 } while (read_seqretry(&xtime_lock, seq));
234 }
235 spin_unlock_irqrestore(&dyn_tick->lock, flags);
236}
237 211
238static ssize_t timer_show_dyn_tick(struct sys_device *dev, char *buf) 212static void __init init_sh_clocksource(void)
239{ 213{
240 return sprintf(buf, "%i\n", 214 if (!sh_hpt_frequency || clocksource_sh.read == null_hpt_read)
241 (sys_timer->dyn_tick->state & DYN_TICK_ENABLED) >> 1); 215 return;
242}
243 216
244static ssize_t timer_set_dyn_tick(struct sys_device *dev, const char *buf, 217 clocksource_sh.mult = clocksource_hz2mult(sh_hpt_frequency,
245 size_t count) 218 clocksource_sh.shift);
246{
247 unsigned int enable = simple_strtoul(buf, NULL, 2);
248 219
249 if (enable) 220 timer_ticks_per_nsec_quotient =
250 timer_dyn_tick_enable(); 221 clocksource_hz2mult(sh_hpt_frequency, NSEC_PER_CYC_SHIFT);
251 else
252 timer_dyn_tick_disable();
253 222
254 return count; 223 clocksource_register(&clocksource_sh);
255} 224}
256static SYSDEV_ATTR(dyn_tick, 0644, timer_show_dyn_tick, timer_set_dyn_tick);
257 225
258/* 226#ifdef CONFIG_GENERIC_TIME
259 * dyntick=enable|disable 227unsigned long long sched_clock(void)
260 */
261static char dyntick_str[4] __initdata = "";
262
263static int __init dyntick_setup(char *str)
264{ 228{
265 if (str) 229 unsigned long long ticks = clocksource_sh.read();
266 strlcpy(dyntick_str, str, sizeof(dyntick_str)); 230 return (ticks * timer_ticks_per_nsec_quotient) >> NSEC_PER_CYC_SHIFT;
267 return 1;
268} 231}
269
270__setup("dyntick=", dyntick_setup);
271#endif
272
273static int __init timer_init_sysfs(void)
274{
275 int ret = sysdev_class_register(&timer_sysclass);
276 if (ret != 0)
277 return ret;
278
279 sys_timer->dev.cls = &timer_sysclass;
280 ret = sysdev_register(&sys_timer->dev);
281
282#ifdef CONFIG_NO_IDLE_HZ
283 if (ret == 0 && sys_timer->dyn_tick) {
284 ret = sysdev_create_file(&sys_timer->dev, &attr_dyn_tick);
285
286 /*
287 * Turn on dynamic tick after calibrate delay
288 * for correct bogomips
289 */
290 if (ret == 0 && dyntick_str[0] == 'e')
291 ret = timer_dyn_tick_enable();
292 }
293#endif 232#endif
294 233
295 return ret;
296}
297device_initcall(timer_init_sysfs);
298
299void (*board_time_init)(void);
300
301void __init time_init(void) 234void __init time_init(void)
302{ 235{
303 if (board_time_init) 236 if (board_time_init)
@@ -316,10 +249,15 @@ void __init time_init(void)
316 sys_timer = get_sys_timer(); 249 sys_timer = get_sys_timer();
317 printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); 250 printk(KERN_INFO "Using %s for system timer\n", sys_timer->name);
318 251
319#ifdef CONFIG_NO_IDLE_HZ 252 if (sys_timer->ops->read)
320 if (sys_timer->dyn_tick) 253 clocksource_sh.read = sys_timer->ops->read;
321 spin_lock_init(&sys_timer->dyn_tick->lock); 254
322#endif 255 init_sh_clocksource();
256
257 if (sh_hpt_frequency)
258 printk("Using %lu.%03lu MHz high precision timer.\n",
259 ((sh_hpt_frequency + 500) / 1000) / 1000,
260 ((sh_hpt_frequency + 500) / 1000) % 1000);
323 261
324#if defined(CONFIG_SH_KGDB) 262#if defined(CONFIG_SH_KGDB)
325 /* 263 /*