4 * This file is part of BeRTOS.
6 * Bertos is free software; you can redistribute it and/or modify
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12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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)
48 * Include platform-specific binding header if we're hosted.
49 * Try the CPU specific one for bare-metal environments.
52 #include OS_HEADER(timer)
54 #include CPU_HEADER(timer)
57 #include <mware/list.h>
58 #include <cfg/debug.h>
59 #include <cfg/compiler.h>
60 #include <appconfig.h>
63 extern volatile ticks_t _clock;
66 * \brief Return the system tick counter (expressed in ticks)
68 * The result is guaranteed to increment monotonically,
69 * but client code must be tolerant with respect to overflows.
71 * The following code is safe:
74 * ticks_t tea_start_time = timer_clock();
78 * if (timer_clock() - tea_start_time > TEAPOT_DELAY)
79 * printf("Your tea, Sir.\n");
82 * \note This function must disable interrupts on 8/16bit CPUs because the
83 * clock variable is larger than the processor word size and can't
84 * be copied atomically.
86 INLINE ticks_t timer_clock(void)
90 ATOMIC(result = _clock);
96 * Faster version of timer_clock(), to be called only when the timer
97 * interrupt is disabled (DISABLE_INTS) or overridden by a
98 * higher-priority or non-nesting interrupt.
102 INLINE ticks_t timer_clock_unlocked(void)
107 /** Convert \a ms [ms] to ticks. */
108 INLINE ticks_t ms_to_ticks(mtime_t ms)
110 #if TIMER_TICKS_PER_SEC < 1000
111 /* Slow timer: avoid rounding down too much. */
112 return (ms * TIMER_TICKS_PER_SEC) / 1000;
114 /* Fast timer: don't overflow ticks_t. */
115 return ms * ((TIMER_TICKS_PER_SEC + 500) / 1000);
119 /** Convert \a us [us] to ticks. */
120 INLINE ticks_t us_to_ticks(utime_t us)
122 #if TIMER_TICKS_PER_SEC < 1000
123 /* Slow timer: avoid rounding down too much. */
124 return ((us / 1000) * TIMER_TICKS_PER_SEC) / 1000;
126 /* Fast timer: don't overflow ticks_t. */
127 return (us * ((TIMER_TICKS_PER_SEC + 500) / 1000)) / 1000;
131 /** Convert \a ticks [ticks] to ms. */
132 INLINE mtime_t ticks_to_ms(ticks_t ticks)
134 #if TIMER_TICKS_PER_SEC < 1000
135 /* Slow timer: avoid rounding down too much. */
136 return (ticks * 1000) / TIMER_TICKS_PER_SEC;
138 /* Fast timer: avoid overflowing ticks_t. */
139 return ticks / (TIMER_TICKS_PER_SEC / 1000);
143 /** Convert \a ticks [ticks] to us. */
144 INLINE utime_t ticks_to_us(ticks_t ticks)
146 #if TIMER_TICKS_PER_SEC < 1000
147 /* Slow timer: avoid rounding down too much. */
148 return ((ticks * 1000) / TIMER_TICKS_PER_SEC) * 1000;
150 /* Fast timer: avoid overflowing ticks_t. */
151 return (ticks / (TIMER_TICKS_PER_SEC / 1000)) * 1000;
155 /** Convert \a us [us] to hpticks */
156 INLINE hptime_t us_to_hptime(utime_t us)
158 #if TIMER_HW_HPTICKS_PER_SEC > 10000000UL
159 return us * ((TIMER_HW_HPTICKS_PER_SEC + 500000UL) / 1000000UL);
161 return (us * ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL) + 500) / 1000UL;
165 /** Convert \a hpticks [hptime] to usec */
166 INLINE utime_t hptime_to_us(hptime_t hpticks)
168 #if TIMER_HW_HPTICKS_PER_SEC < 100000UL
169 return hpticks * ((1000000UL + TIMER_HW_HPTICKS_PER_SEC / 2) / TIMER_HW_HPTICKS_PER_SEC);
171 return (hpticks * 1000UL) / ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL);
172 #endif /* TIMER_HW_HPTICKS_PER_SEC < 100000UL */
176 void timer_init(void);
177 void timer_delayTicks(ticks_t delay);
178 INLINE void timer_delay(mtime_t delay)
180 timer_delayTicks(ms_to_ticks(delay));
183 #if !defined(CONFIG_TIMER_DISABLE_UDELAY)
184 void timer_busyWait(hptime_t delay);
185 void timer_delayHp(hptime_t delay);
186 INLINE void timer_udelay(utime_t delay)
188 timer_delayHp(us_to_hptime(delay));
192 #ifndef CONFIG_TIMER_DISABLE_EVENTS
194 #include <mware/event.h>
197 * The timer driver supports multiple synchronous timers
198 * that can trigger an event when they expire.
205 Node link; /**< Link into timers queue */
206 ticks_t _delay; /**< Timer delay in ms */
207 ticks_t tick; /**< Timer will expire at this tick */
208 Event expire; /**< Event to execute when the timer expires */
212 /** Timer is active when Timer.magic contains this value (for debugging purposes). */
213 #define TIMER_MAGIC_ACTIVE 0xABBA
214 #define TIMER_MAGIC_INACTIVE 0xBAAB
216 extern void timer_add(Timer *timer);
217 extern Timer *timer_abort(Timer *timer);
219 /** Set the timer so that it calls an user hook when it expires */
220 INLINE void timer_set_event_softint(Timer *timer, Hook func, iptr_t user_data)
222 event_initSoftInt(&timer->expire, func, user_data);
225 /** Set the timer delay (the time before the event will be triggered) */
226 INLINE void timer_setDelay(Timer *timer, ticks_t delay)
228 timer->_delay = delay;
231 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
233 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
235 /** Set the timer so that it sends a signal when it expires */
236 INLINE void timer_set_event_signal(Timer *timer, struct Process *proc, sigmask_t sigs)
238 event_initSignal(&timer->expire, proc, sigs);
241 #endif /* CONFIG_KERN_SIGNALS */
244 #endif /* DRV_TIMER_H */