4 * This file is part of BeRTOS.
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13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
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18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * As a special exception, you may use this file as part of a free software
21 * library without restriction. Specifically, if other files instantiate
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24 * file does not by itself cause the resulting executable to be covered by
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26 * invalidate any other reasons why the executable file might be covered by
27 * the GNU General Public License.
29 * Copyright 2003, 2004, 2005 Develer S.r.l. (http://www.develer.com/)
30 * Copyright 2000 Bernardo Innocenti <bernie@develer.com>
36 * \author Bernardo Innocenti <bernie@develer.com>
38 * \brief Hardware independent timer driver (interface)
45 #include <cfg/macros.h>
51 * Include platform-specific binding header if we're hosted.
52 * Try the CPU specific one for bare-metal environments.
55 #include OS_HEADER(timer)
57 #include CPU_HEADER(timer)
60 #include <mware/list.h>
61 #include <cfg/debug.h>
62 #include <cfg/compiler.h>
63 #include <appconfig.h>
66 extern volatile ticks_t _clock;
69 * \brief Return the system tick counter (expressed in ticks)
71 * The result is guaranteed to increment monotonically,
72 * but client code must be tolerant with respect to overflows.
74 * The following code is safe:
77 * ticks_t tea_start_time = timer_clock();
81 * if (timer_clock() - tea_start_time > TEAPOT_DELAY)
82 * printf("Your tea, Sir.\n");
85 * \note This function must disable interrupts on 8/16bit CPUs because the
86 * clock variable is larger than the processor word size and can't
87 * be copied atomically.
89 INLINE ticks_t timer_clock(void)
93 ATOMIC(result = _clock);
99 * Faster version of timer_clock(), to be called only when the timer
100 * interrupt is disabled (DISABLE_INTS) or overridden by a
101 * higher-priority or non-nesting interrupt.
105 INLINE ticks_t timer_clock_unlocked(void)
110 /** Convert \a ms [ms] to ticks. */
111 INLINE ticks_t ms_to_ticks(mtime_t ms)
113 #if TIMER_TICKS_PER_SEC < 1000
114 /* Slow timer: avoid rounding down too much. */
115 return (ms * TIMER_TICKS_PER_SEC) / 1000;
117 /* Fast timer: don't overflow ticks_t. */
118 return ms * DIV_ROUND(TIMER_TICKS_PER_SEC, 1000);
122 /** Convert \a us [us] to ticks. */
123 INLINE ticks_t us_to_ticks(utime_t us)
125 #if TIMER_TICKS_PER_SEC < 1000
126 /* Slow timer: avoid rounding down too much. */
127 return ((us / 1000) * TIMER_TICKS_PER_SEC) / 1000;
129 /* Fast timer: don't overflow ticks_t. */
130 return (us * DIV_ROUND(TIMER_TICKS_PER_SEC, 1000)) / 1000;
134 /** Convert \a ticks [ticks] to ms. */
135 INLINE mtime_t ticks_to_ms(ticks_t ticks)
137 #if TIMER_TICKS_PER_SEC < 1000
138 /* Slow timer: avoid rounding down too much. */
139 return (ticks * 1000) / TIMER_TICKS_PER_SEC;
141 /* Fast timer: avoid overflowing ticks_t. */
142 return ticks / (TIMER_TICKS_PER_SEC / 1000);
146 /** Convert \a ticks [ticks] to us. */
147 INLINE utime_t ticks_to_us(ticks_t ticks)
149 #if TIMER_TICKS_PER_SEC < 1000
150 /* Slow timer: avoid rounding down too much. */
151 return ((ticks * 1000) / TIMER_TICKS_PER_SEC) * 1000;
153 /* Fast timer: avoid overflowing ticks_t. */
154 return (ticks / (TIMER_TICKS_PER_SEC / 1000)) * 1000;
158 /** Convert \a us [us] to hpticks */
159 INLINE hptime_t us_to_hptime(utime_t us)
161 #if TIMER_HW_HPTICKS_PER_SEC > 10000000UL
162 return us * DIV_ROUND(TIMER_HW_HPTICKS_PER_SEC, 1000000UL);
164 return (us * ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL) + 500) / 1000UL;
168 /** Convert \a hpticks [hptime] to usec */
169 INLINE utime_t hptime_to_us(hptime_t hpticks)
171 #if TIMER_HW_HPTICKS_PER_SEC < 100000UL
172 return hpticks * DIV_ROUND(1000000UL, TIMER_HW_HPTICKS_PER_SEC);
174 return (hpticks * 1000UL) / DIV_ROUND(TIMER_HW_HPTICKS_PER_SEC, 1000UL);
175 #endif /* TIMER_HW_HPTICKS_PER_SEC < 100000UL */
179 void timer_init(void);
180 void timer_delayTicks(ticks_t delay);
181 INLINE void timer_delay(mtime_t delay)
183 timer_delayTicks(ms_to_ticks(delay));
186 #if !defined(CONFIG_TIMER_DISABLE_UDELAY)
187 void timer_busyWait(hptime_t delay);
188 void timer_delayHp(hptime_t delay);
189 INLINE void timer_udelay(utime_t delay)
191 timer_delayHp(us_to_hptime(delay));
195 #ifndef CONFIG_TIMER_DISABLE_EVENTS
197 #include <mware/event.h>
200 * The timer driver supports multiple synchronous timers
201 * that can trigger an event when they expire.
208 Node link; /**< Link into timers queue */
209 ticks_t _delay; /**< Timer delay in ms */
210 ticks_t tick; /**< Timer will expire at this tick */
211 Event expire; /**< Event to execute when the timer expires */
215 /** Timer is active when Timer.magic contains this value (for debugging purposes). */
216 #define TIMER_MAGIC_ACTIVE 0xABBA
217 #define TIMER_MAGIC_INACTIVE 0xBAAB
219 extern void timer_add(Timer *timer);
220 extern Timer *timer_abort(Timer *timer);
222 /** Set the timer so that it calls an user hook when it expires */
223 INLINE void timer_set_event_softint(Timer *timer, Hook func, iptr_t user_data)
225 event_initSoftInt(&timer->expire, func, user_data);
228 /** Set the timer delay (the time before the event will be triggered) */
229 INLINE void timer_setDelay(Timer *timer, ticks_t delay)
231 timer->_delay = delay;
234 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
236 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
238 /** Set the timer so that it sends a signal when it expires */
239 INLINE void timer_set_event_signal(Timer *timer, struct Process *proc, sigmask_t sigs)
241 event_initSignal(&timer->expire, proc, sigs);
244 #endif /* CONFIG_KERN_SIGNALS */
247 #endif /* DRV_TIMER_H */