4 * Copyright 2003, 2004 Develer S.r.l. (http://www.develer.com/)
5 * Copyright 2000 Bernardo Innocenti <bernie@develer.com>
6 * This file is part of DevLib - See devlib/README for information.
9 * \brief Hardware independent timer driver (implementation)
12 * \author Bernardo Innocenti <bernie@develer.com>
17 *#* Revision 1.20 2004/11/16 20:59:06 bernie
18 *#* Add watchdog timer support.
20 *#* Revision 1.19 2004/10/19 08:56:49 bernie
21 *#* TIMER_STROBE_ON, TIMER_STROBE_OFF, TIMER_STROBE_INIT: Move from timer_avr.h to timer.h, where they really belong.
23 *#* Revision 1.18 2004/10/14 23:14:05 bernie
24 *#* Fix longstanding problem with wrap-arounds.
26 *#* Revision 1.17 2004/10/03 18:52:08 bernie
27 *#* Move \brief on top in header to please Doxygen.
29 *#* Revision 1.16 2004/10/03 18:48:01 bernie
30 *#* timer_delay(): Add a sanity check to avoid sleeping forever.
32 *#* Revision 1.15 2004/09/14 21:07:18 bernie
33 *#* Use debug.h instead of kdebug.h.
35 *#* Revision 1.14 2004/08/25 14:12:08 rasky
36 *#* Aggiornato il comment block dei log RCS
38 *#* Revision 1.13 2004/08/10 06:59:09 bernie
39 *#* timer_gettick(): Rename to timer_ticks() and add backwards compatibility inline.
41 *#* Revision 1.12 2004/08/08 05:59:37 bernie
42 *#* Remove a few useless casts.
44 *#* Revision 1.11 2004/08/02 20:20:29 aleph
45 *#* Merge from project_ks
47 *#* Revision 1.10 2004/07/30 14:15:53 rasky
48 *#* Nuovo supporto unificato per detect della CPU
50 *#* Revision 1.9 2004/07/21 00:15:13 bernie
51 *#* Put timer driver on diet.
53 *#* Revision 1.8 2004/07/18 21:57:07 bernie
54 *#* Fix preprocessor warning with potentially undefined symbol.
56 *#* Revision 1.6 2004/06/07 18:10:06 aleph
57 *#* Remove free pool of timers; use user-provided Timer structure instead
59 *#* Revision 1.5 2004/06/07 15:56:55 aleph
60 *#* Some tabs cleanup and add timer strobe macros
62 *#* Revision 1.4 2004/06/06 18:25:44 bernie
63 *#* Rename event macros to look like regular functions.
65 *#* Revision 1.3 2004/06/06 17:18:42 bernie
66 *#* Fix \!CONFIG_KERN_SIGNALS code paths.
68 *#* Revision 1.2 2004/06/03 11:27:09 bernie
69 *#* Add dual-license information.
71 *#* Revision 1.1 2004/05/23 18:23:30 bernie
72 *#* Import drv/timer module.
79 #include CPU_HEADER(timer)
84 * Sanity check for config parameters required by this module.
86 #if !defined(CONFIG_KERNEL) || ((CONFIG_KERNEL != 0) && CONFIG_KERNEL != 1)
87 #error CONFIG_KERNEL must be set to either 0 or 1 in config.h
89 #if !defined(CONFIG_WATCHDOG) || ((CONFIG_WATCHDOG != 0) && CONFIG_WATCHDOG != 1)
90 #error CONFIG_WATCHDOG must be set to either 0 or 1 in config.h
97 #if CONFIG_KERNEL && CONFIG_KERN_SIGNALS
98 #include <kern/proc.h>
103 * \def CONFIG_TIMER_STROBE
105 * This is a debug facility that can be used to
106 * monitor timer interrupt activity on an external pin.
108 * To use strobes, redefine the macros TIMER_STROBE_ON,
109 * TIMER_STROBE_OFF and TIMER_STROBE_INIT and set
110 * CONFIG_TIMER_STROBE to 1.
112 #if !defined(CONFIG_TIMER_STROBE) || !CONFIG_TIMER_STROBE
113 #define TIMER_STROBE_ON do {/*nop*/} while(0)
114 #define TIMER_STROBE_OFF do {/*nop*/} while(0)
115 #define TIMER_STROBE_INIT do {/*nop*/} while(0)
119 //! Master system clock (1ms accuracy)
120 volatile time_t _clock;
123 #ifndef CONFIG_TIMER_DISABLE_EVENTS
126 * List of active asynchronous timers.
128 REGISTER static List timers_queue;
132 * Add the specified timer to the software timer service queue.
133 * When the delay indicated by the timer expires, the timer
134 * device will execute the event associated with it.
136 * \note Interrupt safe
138 void timer_add(Timer *timer)
143 DISABLE_IRQSAVE(flags);
145 /* Calculate expiration time for this timer */
146 timer->tick = _clock + timer->delay;
149 * Search for the first node whose expiration time is
150 * greater than the timer we want to add.
152 node = (Timer *)timers_queue.head;
153 while (node->link.succ)
156 * Stop just after the insertion point.
157 * (this fancy compare takes care of wrap-arounds).
159 if (node->tick - timer->tick > 0)
162 /* Go to next node */
163 node = (Timer *)node->link.succ;
166 /* Enqueue timer request into the list */
167 INSERTBEFORE(&timer->link, &node->link);
169 ENABLE_IRQRESTORE(flags);
174 * Remove a timer from the timer queue before it has expired
176 Timer *timer_abort(Timer *timer)
179 DISABLE_IRQSAVE(flags);
180 REMOVE(&timer->link);
181 ENABLE_IRQRESTORE(flags);
186 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
190 * Wait for the specified amount of time (expressed in ms)
192 void timer_delay(time_t time)
194 #if defined(IRQ_GETSTATE)
195 /* We shouldn't sleep with interrupts disabled */
196 ASSERT(IRQ_GETSTATE());
199 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
202 ASSERT(!sig_check(SIG_SINGLE));
203 timer_set_event_signal(&t, proc_current(), SIG_SINGLE);
204 timer_set_delay(&t, time);
206 sig_wait(SIG_SINGLE);
208 #else /* !CONFIG_KERN_SIGNALS */
210 time_t start = timer_ticks();
213 while (timer_ticks() - start < time)
220 #endif /* !CONFIG_KERN_SIGNALS */
224 #ifndef CONFIG_TIMER_DISABLE_UDELAY
226 * Wait for the specified amount of time (expressed in microseconds)
228 * \bug In AVR arch the maximum amount of time that can be used as
229 * delay could be very limited, depending on the hardware timer
230 * used. Check timer_avr.h, and what register is used as hptime_t.
232 void timer_udelay(utime_t usec_delay)
234 if (UNLIKELY(usec_delay > 1000))
236 timer_delay(usec_delay / 1000);
240 // FIXME: This multiplication is too slow at run-time. We should try and move it
241 // to compile-time by exposing the TIMER_HW_HPTICKS_PER_SEC in the header
243 hptime_t start = timer_hw_hpread();
244 hptime_t delay = (uint32_t)usec_delay * TIMER_HW_HPTICKS_PER_SEC / 1000000ul;
246 while (timer_hw_hpread() - start < delay)
249 #endif /* CONFIG_TIMER_DISABLE_UDELAY */
253 * Timer interrupt handler. Find soft timers expired and
254 * trigger corresponding events.
259 * With the Metrowerks compiler, the only way to force the compiler generate
260 * an interrupt service routine is to put a pragma directive within the function
264 #pragma interrupt saveall
267 #ifndef CONFIG_TIMER_DISABLE_EVENTS
275 /* Update the master ms counter */
278 #ifndef CONFIG_TIMER_DISABLE_EVENTS
280 * Check the first timer request in the list and process
281 * it when it has expired. Repeat this check until the
282 * first node has not yet expired. Since the list is sorted
283 * by expiry time, all the following requests are guaranteed
286 while ((timer = (Timer *)timers_queue.head)->link.succ)
288 /* This request in list has not yet expired? */
289 if (_clock < timer->tick)
292 /* Retreat the expired timer */
293 REMOVE(&timer->link);
295 /* Execute the associated event */
296 event_do(&timer->expire);
298 #endif /* CONFIG_TIMER_DISABLE_EVENTS */
307 void timer_init(void)
311 #ifndef CONFIG_TIMER_DISABLE_EVENTS
312 INITLIST(&timers_queue);