-/*!
+/**
* \file
* <!--
- * Copyright 2003,2004 Develer S.r.l. (http://www.develer.com/)
- * Copyright 2000 Bernardo Innocenti <bernie@develer.com>
- * All Rights Reserved.
- * -->
+ * This file is part of BeRTOS.
*
- * \version $Id$
+ * Bertos is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
*
- * \author Bernardo Innocenti <bernie@develer.com>
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction. Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License. This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2003, 2004, 2005, 2006 Develer S.r.l. (http://www.develer.com/)
+ * Copyright 2000 Bernardo Innocenti <bernie@develer.com>
+ *
+ * -->
*
* \brief Hardware independent timer driver (implementation)
- */
-
-/*
- * $Log$
- * Revision 1.1 2004/05/23 18:23:30 bernie
- * Import drv/timer module.
*
+ * \version $Id$
+ * \author Bernardo Innocenti <bernie@develer.com>
*/
-#include "hw.h"
-#include "kdebug.h"
#include "timer.h"
-#ifdef CONFIG_KERN_SIGNALS
-#include <kern/proc.h>
-#endif
-
-#if (ARCH & ARCH_EMUL)
+#include <cpu/attr.h>
+#include <cpu/types.h>
+#include <cpu/irq.h>
-# error To be recoded
+#include <cfg/os.h>
+#include <cfg/debug.h>
+#include <cfg/module.h>
+#include <appconfig.h>
-#elif defined(__AVR__)
-# include "timer_avr.h"
-#elif defined(__IAR_SYSTEMS_ICC) || defined(__IAR_SYSTEMS_ICC__) /* 80C196 */
-# include "timer_i196.h"
-#elif defined (__m56800__)
-# include "timer_dsp56k.h"
+/*
+ * Include platform-specific binding code if we're hosted.
+ * Try the CPU specific one for bare-metal environments.
+ */
+#if OS_HOSTED
+ #include OS_CSOURCE(timer)
#else
-# error Unknown system
+ #include CPU_CSOURCE(timer)
#endif
+/*
+ * Sanity check for config parameters required by this module.
+ */
+#if !defined(CONFIG_KERNEL) || ((CONFIG_KERNEL != 0) && CONFIG_KERNEL != 1)
+ #error CONFIG_KERNEL must be set to either 0 or 1 in config.h
+#endif
+#if !defined(CONFIG_WATCHDOG) || ((CONFIG_WATCHDOG != 0) && CONFIG_WATCHDOG != 1)
+ #error CONFIG_WATCHDOG must be set to either 0 or 1 in config.h
+#endif
-/*! Number of available timers */
-#define MAX_TIMERS 4
-
-
-//! Master system clock (1ms accuracy)
-volatile time_t _clock;
+#if CONFIG_WATCHDOG
+ #include <drv/wdt.h>
+#endif
-static Timer soft_timers[MAX_TIMERS]; /*!< Pool of Timer structures */
-static List timers_pool; /*!< Pool of free timers */
-REGISTER static List timers_queue; /*!< Active timers */
+#if CONFIG_KERNEL
+ #include <config_kern.h>
+ #if CONFIG_KERN_PREEMPTIVE
+ #include <hw/switch.h>
+ #endif
+ #if CONFIG_KERN_SIGNALS
+ #include <kern/signal.h> /* sig_wait(), sig_check() */
+ #include <kern/proc.h> /* proc_current() */
+ #include <cfg/macros.h> /* BV() */
+ #endif
+#endif
-/*!
- * Return a new timer picking and removing it from the available
- * timers pool. Return NULL if no more timers are available.
+/**
+ * \def CONFIG_TIMER_STROBE
+ *
+ * This is a debug facility that can be used to
+ * monitor timer interrupt activity on an external pin.
+ *
+ * To use strobes, redefine the macros TIMER_STROBE_ON,
+ * TIMER_STROBE_OFF and TIMER_STROBE_INIT and set
+ * CONFIG_TIMER_STROBE to 1.
*/
-Timer *timer_new(void)
-{
- Timer *timer;
- cpuflags_t flags;
-
- DISABLE_IRQSAVE(flags);
-
- /* Should never happen */
- if (ISLISTEMPTY(&timers_pool))
- {
- ENABLE_IRQRESTORE(flags);
- DB(kprintf("Tmrspool empty\n");)
- return NULL;
- }
+#if !defined(CONFIG_TIMER_STROBE) || !CONFIG_TIMER_STROBE
+ #define TIMER_STROBE_ON do {/*nop*/} while(0)
+ #define TIMER_STROBE_OFF do {/*nop*/} while(0)
+ #define TIMER_STROBE_INIT do {/*nop*/} while(0)
+#endif
- /* Get a timer from the free pool */
- timer = (Timer *)timers_pool.head;
- REMOVE((Node *)timer);
- ENABLE_IRQRESTORE(flags);
+/// Master system clock (1 tick accuracy)
+volatile ticks_t _clock;
- return timer;
-}
+#ifndef CONFIG_TIMER_DISABLE_EVENTS
-/*!
- * Delete a timer, putting it in the available timers queue.
+/**
+ * List of active asynchronous timers.
*/
-void timer_delete(Timer *timer)
-{
- cpuflags_t flags;
- DISABLE_IRQSAVE(flags);
- ADDHEAD(&timers_pool, &timer->link);
- ENABLE_IRQRESTORE(flags);
-}
+REGISTER static List timers_queue;
-/*!
+/**
* Add the specified timer to the software timer service queue.
* When the delay indicated by the timer expires, the timer
* device will execute the event associated with it.
Timer *node;
cpuflags_t flags;
- DISABLE_IRQSAVE(flags);
+
+ /* Inserting timers twice causes mayhem. */
+ ASSERT(timer->magic != TIMER_MAGIC_ACTIVE);
+ DB(timer->magic = TIMER_MAGIC_ACTIVE;)
+
+ IRQ_SAVE_DISABLE(flags);
/* Calculate expiration time for this timer */
- timer->tick = _clock + timer->delay;
+ timer->tick = _clock + timer->_delay;
- /* Search for the first node whose expiration time is
+ /*
+ * Search for the first node whose expiration time is
* greater than the timer we want to add.
*/
- node = (Timer *)timers_queue.head;
+ node = (Timer *)LIST_HEAD(&timers_queue);
while (node->link.succ)
{
- /* Stop just after the insert point */
- if (node->tick > timer->tick)
+ /*
+ * Stop just after the insertion point.
+ * (this fancy compare takes care of wrap-arounds).
+ */
+ if (node->tick - timer->tick > 0)
break;
/* Go to next node */
}
/* Enqueue timer request into the list */
- INSERTBEFORE((Node *)timer, (Node *)node);
+ INSERT_BEFORE(&timer->link, &node->link);
- ENABLE_IRQRESTORE(flags);
+ IRQ_RESTORE(flags);
}
-/*!
- * Remove a timer from the timer queue before it has expired
+/**
+ * Remove a timer from the timer queue before it has expired.
*/
Timer *timer_abort(Timer *timer)
{
- cpuflags_t flags;
- DISABLE_IRQSAVE(flags);
- REMOVE((Node *)timer);
- ENABLE_IRQRESTORE(flags);
+ ATOMIC(REMOVE(&timer->link));
+ DB(timer->magic = TIMER_MAGIC_INACTIVE;)
return timer;
}
+#endif /* CONFIG_TIMER_DISABLE_EVENTS */
-/*!
- * Wait for the specified amount of time (expressed in ms)
+
+/**
+ * Wait for the specified amount of timer ticks.
*/
-void timer_delay(time_t time)
+void timer_delayTicks(ticks_t delay)
{
-#ifdef CONFIG_KERN_SIGNALS
+#if defined(IRQ_ENABLED)
+ /* We shouldn't sleep with interrupts disabled */
+ ASSERT(IRQ_ENABLED());
+#endif
+
+#if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
Timer t;
ASSERT(!sig_check(SIG_SINGLE));
timer_set_event_signal(&t, proc_current(), SIG_SINGLE);
- timer_set_delay(&t, time);
+ timer_setDelay(&t, delay);
timer_add(&t);
sig_wait(SIG_SINGLE);
-#else
- time_t start = timer_gettick();
- while (timer_gettick() - start < time) { /* nop */ }
+#else /* !CONFIG_KERN_SIGNALS */
+
+ ticks_t start = timer_clock();
+
+ /* Busy wait */
+ while (timer_clock() - start < delay)
+ {
+#if CONFIG_WATCHDOG
+ wdt_reset();
#endif
+ }
+
+#endif /* !CONFIG_KERN_SIGNALS */
}
-/*!
- * Wait for the specified amount of time (expressed in microseconds)
+
+#ifndef CONFIG_TIMER_DISABLE_UDELAY
+
+/**
+ * Busy wait until the specified amount of high-precision ticks have elapsed.
+ *
+ * \note This function is interrupt safe, the only
+ * requirement is a running hardware timer.
*/
-void timer_udelay(utime_t usec_delay)
+void timer_busyWait(hptime_t delay)
{
- if (usec_delay > 1000)
+ hptime_t now, prev = timer_hw_hpread();
+ hptime_t delta;
+
+ for(;;)
{
- timer_delay(usec_delay / 1000);
- usec_delay %= 1000;
+ now = timer_hw_hpread();
+ /*
+ * We rely on hptime_t being unsigned here to
+ * reduce the modulo to an AND in the common
+ * case of TIMER_HW_CNT.
+ */
+ delta = (now - prev) % TIMER_HW_CNT;
+ if (delta >= delay)
+ break;
+ delay -= delta;
+ prev = now;
}
+}
- // FIXME: This multiplication is too slow at run-time. We should try and move it
- // to compile-time by exposing the TIMER_HW_HPTICKS_PER_SEC in the header
- // file.
- hptime_t start = timer_hw_hpread();
- hptime_t delay = (uint32_t)usec_delay * TIMER_HW_HPTICKS_PER_SEC / 1000000ul;
+/**
+ * Wait for the specified amount of time (expressed in microseconds).
+ *
+ * \bug In AVR arch the maximum amount of time that can be used as
+ * delay could be very limited, depending on the hardware timer
+ * used. Check timer_avr.h, and what register is used as hptime_t.
+ */
+void timer_delayHp(hptime_t delay)
+{
+ if (UNLIKELY(delay > us_to_hptime(1000)))
+ {
+ timer_delayTicks(delay / (TIMER_HW_HPTICKS_PER_SEC / TIMER_TICKS_PER_SEC));
+ delay %= (TIMER_HW_HPTICKS_PER_SEC / TIMER_TICKS_PER_SEC);
+ }
- while (timer_hw_hpread() - start < delay)
- {}
+ timer_busyWait(delay);
}
+#endif /* CONFIG_TIMER_DISABLE_UDELAY */
-/*!
+/**
* Timer interrupt handler. Find soft timers expired and
* trigger corresponding events.
*/
DEFINE_TIMER_ISR
{
- /* With the Metrowerks compiler, the only way to force the compiler generate
- an interrupt service routine is to put a pragma directive within the function
- body. */
+ /*
+ * With the Metrowerks compiler, the only way to force the compiler generate
+ * an interrupt service routine is to put a pragma directive within the function
+ * body.
+ */
#ifdef __MWERKS__
#pragma interrupt saveall
#endif
+#ifndef CONFIG_TIMER_DISABLE_EVENTS
Timer *timer;
+#endif
+ /*
+ * On systems sharing IRQ line and vector, this check is needed
+ * to ensure that IRQ is generated by timer source.
+ */
+ if (!timer_hw_triggered())
+ return;
+ TIMER_STROBE_ON;
+
+ /* Perform hw IRQ handling */
timer_hw_irq();
/* Update the master ms counter */
++_clock;
+#ifndef CONFIG_TIMER_DISABLE_EVENTS
/*
* Check the first timer request in the list and process
* it when it has expired. Repeat this check until the
* by expiry time, all the following requests are guaranteed
* to expire later.
*/
- while ((timer = (Timer *)timers_queue.head)->link.succ)
+ while ((timer = (Timer *)LIST_HEAD(&timers_queue))->link.succ)
{
/* This request in list has not yet expired? */
- if (_clock < timer->tick)
+ if (_clock - timer->tick < 0)
break;
/* Retreat the expired timer */
- REMOVE((Node *)timer);
+ REMOVE(&timer->link);
+ DB(timer->magic = TIMER_MAGIC_INACTIVE;)
/* Execute the associated event */
- DOEVENT_INTR(&timer->expire);
+ event_do(&timer->expire);
}
-}
+#endif /* CONFIG_TIMER_DISABLE_EVENTS */
+ TIMER_STROBE_OFF;
+}
+MOD_DEFINE(timer)
-/*!
+/**
* Initialize timer
*/
void timer_init(void)
{
- int i;
-
- INITLIST(&timers_queue);
- INITLIST(&timers_pool);
+ TIMER_STROBE_INIT;
- /* Init all software timers in the free pool */
- for (i = 0; i < MAX_TIMERS; i++)
- ADDTAIL(&timers_pool, (Node *)&soft_timers[i]);
+#ifndef CONFIG_TIMER_DISABLE_EVENTS
+ LIST_INIT(&timers_queue);
+#endif
_clock = 0;
timer_hw_init();
-}
+ MOD_INIT(timer);
+}