4 * This file is part of BeRTOS.
6 * Bertos is free software; you can redistribute it and/or modify
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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
22 * templates or use macros or inline functions from this file, or you compile
23 * this file and link it with other files to produce an executable, this
24 * file does not by itself cause the resulting executable to be covered by
25 * the GNU General Public License. This exception does not however
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)
49 * Include platform-specific binding header if we're hosted.
50 * Try the CPU specific one for bare-metal environments.
53 #include OS_HEADER(timer)
55 #include CPU_HEADER(timer)
58 #include <mware/list.h>
59 #include <cfg/debug.h>
60 #include <cfg/compiler.h>
61 #include <appconfig.h>
64 extern volatile ticks_t _clock;
67 * \brief Return the system tick counter (expressed in ticks)
69 * The result is guaranteed to increment monotonically,
70 * but client code must be tolerant with respect to overflows.
72 * The following code is safe:
75 * ticks_t tea_start_time = timer_clock();
79 * if (timer_clock() - tea_start_time > TEAPOT_DELAY)
80 * printf("Your tea, Sir.\n");
83 * \note This function must disable interrupts on 8/16bit CPUs because the
84 * clock variable is larger than the processor word size and can't
85 * be copied atomically.
87 INLINE ticks_t timer_clock(void)
91 ATOMIC(result = _clock);
97 * Faster version of timer_clock(), to be called only when the timer
98 * interrupt is disabled (DISABLE_INTS) or overridden by a
99 * higher-priority or non-nesting interrupt.
103 INLINE ticks_t timer_clock_unlocked(void)
108 /** Convert \a ms [ms] to ticks. */
109 INLINE ticks_t ms_to_ticks(mtime_t ms)
111 #if TIMER_TICKS_PER_SEC < 1000
112 /* Slow timer: avoid rounding down too much. */
113 return (ms * TIMER_TICKS_PER_SEC) / 1000;
115 /* Fast timer: don't overflow ticks_t. */
116 return ms * ((TIMER_TICKS_PER_SEC + 500) / 1000);
120 /** Convert \a us [us] to ticks. */
121 INLINE ticks_t us_to_ticks(utime_t us)
123 #if TIMER_TICKS_PER_SEC < 1000
124 /* Slow timer: avoid rounding down too much. */
125 return ((us / 1000) * TIMER_TICKS_PER_SEC) / 1000;
127 /* Fast timer: don't overflow ticks_t. */
128 return (us * ((TIMER_TICKS_PER_SEC + 500) / 1000)) / 1000;
132 /** Convert \a ticks [ticks] to ms. */
133 INLINE mtime_t ticks_to_ms(ticks_t ticks)
135 #if TIMER_TICKS_PER_SEC < 1000
136 /* Slow timer: avoid rounding down too much. */
137 return (ticks * 1000) / TIMER_TICKS_PER_SEC;
139 /* Fast timer: avoid overflowing ticks_t. */
140 return ticks / (TIMER_TICKS_PER_SEC / 1000);
144 /** Convert \a ticks [ticks] to us. */
145 INLINE utime_t ticks_to_us(ticks_t ticks)
147 #if TIMER_TICKS_PER_SEC < 1000
148 /* Slow timer: avoid rounding down too much. */
149 return ((ticks * 1000) / TIMER_TICKS_PER_SEC) * 1000;
151 /* Fast timer: avoid overflowing ticks_t. */
152 return (ticks / (TIMER_TICKS_PER_SEC / 1000)) * 1000;
156 /** Convert \a us [us] to hpticks */
157 INLINE hptime_t us_to_hptime(utime_t us)
159 #if TIMER_HW_HPTICKS_PER_SEC > 10000000UL
160 return us * ((TIMER_HW_HPTICKS_PER_SEC + 500000UL) / 1000000UL);
162 return (us * ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL) + 500) / 1000UL;
166 /** Convert \a hpticks [hptime] to usec */
167 INLINE utime_t hptime_to_us(hptime_t hpticks)
169 #if TIMER_HW_HPTICKS_PER_SEC < 100000UL
170 return hpticks * ((1000000UL + TIMER_HW_HPTICKS_PER_SEC / 2) / TIMER_HW_HPTICKS_PER_SEC);
172 return (hpticks * 1000UL) / ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL);
173 #endif /* TIMER_HW_HPTICKS_PER_SEC < 100000UL */
177 void timer_init(void);
178 void timer_delayTicks(ticks_t delay);
179 INLINE void timer_delay(mtime_t delay)
181 timer_delayTicks(ms_to_ticks(delay));
184 #if !defined(CONFIG_TIMER_DISABLE_UDELAY)
185 void timer_busyWait(hptime_t delay);
186 void timer_delayHp(hptime_t delay);
187 INLINE void timer_udelay(utime_t delay)
189 timer_delayHp(us_to_hptime(delay));
193 #ifndef CONFIG_TIMER_DISABLE_EVENTS
195 #include <mware/event.h>
198 * The timer driver supports multiple synchronous timers
199 * that can trigger an event when they expire.
206 Node link; /**< Link into timers queue */
207 ticks_t _delay; /**< Timer delay in ms */
208 ticks_t tick; /**< Timer will expire at this tick */
209 Event expire; /**< Event to execute when the timer expires */
213 /** Timer is active when Timer.magic contains this value (for debugging purposes). */
214 #define TIMER_MAGIC_ACTIVE 0xABBA
215 #define TIMER_MAGIC_INACTIVE 0xBAAB
217 extern void timer_add(Timer *timer);
218 extern Timer *timer_abort(Timer *timer);
220 /** Set the timer so that it calls an user hook when it expires */
221 INLINE void timer_set_event_softint(Timer *timer, Hook func, iptr_t user_data)
223 event_initSoftInt(&timer->expire, func, user_data);
226 /** Set the timer delay (the time before the event will be triggered) */
227 INLINE void timer_setDelay(Timer *timer, ticks_t delay)
229 timer->_delay = delay;
232 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
234 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
236 /** Set the timer so that it sends a signal when it expires */
237 INLINE void timer_set_event_signal(Timer *timer, struct Process *proc, sigmask_t sigs)
239 event_initSignal(&timer->expire, proc, sigs);
242 #endif /* CONFIG_KERN_SIGNALS */
245 #endif /* DRV_TIMER_H */