4 * This file is part of BeRTOS.
6 * Bertos is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
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.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
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>
34 * \brief Hardware independent timer driver (interface)
38 * \author Bernardo Innocenti <bernie@develer.com>
46 #include <cfg/macros.h>
53 * Include platform-specific binding header if we're hosted.
54 * Try the CPU specific one for bare-metal environments.
57 #include OS_HEADER(timer)
59 #include CPU_HEADER(timer)
62 #include "cfg/cfg_timer.h"
63 #include <cfg/debug.h>
64 #include <cfg/compiler.h>
66 #include <mware/list.h>
69 extern volatile ticks_t _clock;
72 * \brief Return the system tick counter (expressed in ticks)
74 * The result is guaranteed to increment monotonically,
75 * but client code must be tolerant with respect to overflows.
77 * The following code is safe:
80 * ticks_t tea_start_time = timer_clock();
84 * if (timer_clock() - tea_start_time > TEAPOT_DELAY)
85 * printf("Your tea, Sir.\n");
88 * \note This function must disable interrupts on 8/16bit CPUs because the
89 * clock variable is larger than the processor word size and can't
90 * be copied atomically.
92 INLINE ticks_t timer_clock(void)
96 ATOMIC(result = _clock);
102 * Faster version of timer_clock(), to be called only when the timer
103 * interrupt is disabled (DISABLE_INTS) or overridden by a
104 * higher-priority or non-nesting interrupt.
108 INLINE ticks_t timer_clock_unlocked(void)
113 /** Convert \a ms [ms] to ticks. */
114 INLINE ticks_t ms_to_ticks(mtime_t ms)
116 #if TIMER_TICKS_PER_SEC < 1000
117 /* Slow timer: avoid rounding down too much. */
118 return (ms * TIMER_TICKS_PER_SEC) / 1000;
120 /* Fast timer: don't overflow ticks_t. */
121 return ms * DIV_ROUND(TIMER_TICKS_PER_SEC, 1000);
125 /** Convert \a us [us] to ticks. */
126 INLINE ticks_t us_to_ticks(utime_t us)
128 #if TIMER_TICKS_PER_SEC < 1000
129 /* Slow timer: avoid rounding down too much. */
130 return ((us / 1000) * TIMER_TICKS_PER_SEC) / 1000;
132 /* Fast timer: don't overflow ticks_t. */
133 return (us * DIV_ROUND(TIMER_TICKS_PER_SEC, 1000)) / 1000;
137 /** Convert \a ticks [ticks] to ms. */
138 INLINE mtime_t ticks_to_ms(ticks_t ticks)
140 #if TIMER_TICKS_PER_SEC < 1000
141 /* Slow timer: avoid rounding down too much. */
142 return (ticks * 1000) / TIMER_TICKS_PER_SEC;
144 /* Fast timer: avoid overflowing ticks_t. */
145 return ticks / (TIMER_TICKS_PER_SEC / 1000);
149 /** Convert \a ticks [ticks] to us. */
150 INLINE utime_t ticks_to_us(ticks_t ticks)
152 #if TIMER_TICKS_PER_SEC < 1000
153 /* Slow timer: avoid rounding down too much. */
154 return ((ticks * 1000) / TIMER_TICKS_PER_SEC) * 1000;
156 /* Fast timer: avoid overflowing ticks_t. */
157 return (ticks / (TIMER_TICKS_PER_SEC / 1000)) * 1000;
161 /** Convert \a us [us] to hpticks */
162 INLINE hptime_t us_to_hptime(utime_t us)
164 #if TIMER_HW_HPTICKS_PER_SEC > 10000000UL
165 return us * DIV_ROUND(TIMER_HW_HPTICKS_PER_SEC, 1000000UL);
167 return (us * ((TIMER_HW_HPTICKS_PER_SEC + 500) / 1000UL) + 500) / 1000UL;
171 /** Convert \a hpticks [hptime] to usec */
172 INLINE utime_t hptime_to_us(hptime_t hpticks)
174 #if TIMER_HW_HPTICKS_PER_SEC < 100000UL
175 return hpticks * DIV_ROUND(1000000UL, TIMER_HW_HPTICKS_PER_SEC);
177 return (hpticks * 1000UL) / DIV_ROUND(TIMER_HW_HPTICKS_PER_SEC, 1000UL);
178 #endif /* TIMER_HW_HPTICKS_PER_SEC < 100000UL */
182 void timer_init(void);
183 void timer_delayTicks(ticks_t delay);
184 INLINE void timer_delay(mtime_t delay)
186 timer_delayTicks(ms_to_ticks(delay));
189 #if !defined(CONFIG_TIMER_DISABLE_UDELAY)
190 void timer_busyWait(hptime_t delay);
191 void timer_delayHp(hptime_t delay);
192 INLINE void timer_udelay(utime_t delay)
194 timer_delayHp(us_to_hptime(delay));
198 #ifndef CONFIG_TIMER_DISABLE_EVENTS
200 #include <mware/event.h>
203 * The timer driver supports multiple synchronous timers
204 * that can trigger an event when they expire.
211 Node link; /**< Link into timers queue */
212 ticks_t _delay; /**< Timer delay in ms */
213 ticks_t tick; /**< Timer will expire at this tick */
214 Event expire; /**< Event to execute when the timer expires */
218 /** Timer is active when Timer.magic contains this value (for debugging purposes). */
219 #define TIMER_MAGIC_ACTIVE 0xABBA
220 #define TIMER_MAGIC_INACTIVE 0xBAAB
222 extern void timer_add(Timer *timer);
223 extern Timer *timer_abort(Timer *timer);
225 /** Set the timer so that it calls an user hook when it expires */
226 INLINE void timer_set_event_softint(Timer *timer, Hook func, iptr_t user_data)
228 event_initSoftInt(&timer->expire, func, user_data);
231 /** Set the timer delay (the time before the event will be triggered) */
232 INLINE void timer_setDelay(Timer *timer, ticks_t delay)
234 timer->_delay = delay;
237 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
239 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
241 /** Set the timer so that it sends a signal when it expires */
242 INLINE void timer_set_event_signal(Timer *timer, struct Process *proc, sigmask_t sigs)
244 event_initSignal(&timer->expire, proc, sigs);
247 #endif /* CONFIG_KERN_SIGNALS */
250 #endif /* DRV_TIMER_H */