/****************************************************************************
* sched/wdog/wd_start.c
*
* Copyright (C) 2007-2009, 2012, 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdarg.h>
#include <unistd.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/arch.h>
#include <nuttx/wdog.h>
#include "sched/sched.h"
#include "wdog/wdog.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
/****************************************************************************
* Private Type Declarations
****************************************************************************/
typedef void (*wdentry0_t)(int argc);
#if CONFIG_MAX_WDOGPARMS > 0
typedef void (*wdentry1_t)(int argc, uint32_t arg1);
#endif
#if CONFIG_MAX_WDOGPARMS > 1
typedef void (*wdentry2_t)(int argc, uint32_t arg1, uint32_t arg2);
#endif
#if CONFIG_MAX_WDOGPARMS > 2
typedef void (*wdentry3_t)(int argc, uint32_t arg1, uint32_t arg2,
uint32_t arg3);
#endif
#if CONFIG_MAX_WDOGPARMS > 3
typedef void (*wdentry4_t)(int argc, uint32_t arg1, uint32_t arg2,
uint32_t arg3, uint32_t arg4);
#endif
/****************************************************************************
* Global Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: wd_expiration
*
* Description:
* Check if the timer for the watchdog at the head of list is ready to
* run. If so, remove the watchdog from the list and execute it.
*
* Parameters:
* None
*
* Return Value:
* None
*
* Assumptions:
*
****************************************************************************/
static inline void wd_expiration(void)
{
FAR struct wdog_s *wdog;
/* Check if the watchdog at the head of the list is ready to run */
if (((FAR struct wdog_s *)g_wdactivelist.head)->lag <= 0)
{
/* Process the watchdog at the head of the list as well as any
* other watchdogs that became ready to run at this time
*/
while (g_wdactivelist.head &&
((FAR struct wdog_s *)g_wdactivelist.head)->lag <= 0)
{
/* Remove the watchdog from the head of the list */
wdog = (FAR struct wdog_s *)sq_remfirst(&g_wdactivelist);
/* If there is another watchdog behind this one, update its
* its lag (this shouldn't be necessary).
*/
if (g_wdactivelist.head)
{
((FAR struct wdog_s *)g_wdactivelist.head)->lag += wdog->lag;
}
/* Indicate that the watchdog is no longer active. */
WDOG_CLRACTIVE(wdog);
/* Execute the watchdog function */
up_setpicbase(wdog->picbase);
switch (wdog->argc)
{
default:
DEBUGPANIC();
break;
case 0:
(*((wdentry0_t)(wdog->func)))(0);
break;
#if CONFIG_MAX_WDOGPARMS > 0
case 1:
(*((wdentry1_t)(wdog->func)))(1, wdog->parm[0]);
break;
#endif
#if CONFIG_MAX_WDOGPARMS > 1
case 2:
(*((wdentry2_t)(wdog->func)))(2,
wdog->parm[0], wdog->parm[1]);
break;
#endif
#if CONFIG_MAX_WDOGPARMS > 2
case 3:
(*((wdentry3_t)(wdog->func)))(3,
wdog->parm[0], wdog->parm[1],
wdog->parm[2]);
break;
#endif
#if CONFIG_MAX_WDOGPARMS > 3
case 4:
(*((wdentry4_t)(wdog->func)))(4,
wdog->parm[0], wdog->parm[1],
wdog->parm[2] ,wdog->parm[3]);
break;
#endif
}
}
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: wd_start
*
* Description:
* This function adds a watchdog to the timer queue. The specified
* watchdog function will be called from the interrupt level after the
* specified number of ticks has elapsed. Watchdog timers may be started
* from the interrupt level.
*
* Watchdog timers execute in the address environment that was in effect
* when wd_start() is called.
*
* Watchdog timers execute only once.
*
* To replace either the timeout delay or the function to be executed,
* call wd_start again with the same wdog; only the most recent wdStart()
* on a given watchdog ID has any effect.
*
* Parameters:
* wdog = watchdog ID
* delay = Delay count in clock ticks
* wdentry = function to call on timeout
* parm1..4 = parameters to pass to wdentry
*
* Return Value:
* OK or ERROR
*
* Assumptions:
* The watchdog routine runs in the context of the timer interrupt handler
* and is subject to all ISR restrictions.
*
****************************************************************************/
int wd_start(WDOG_ID wdog, int delay, wdentry_t wdentry, int argc, ...)
{
va_list ap;
FAR struct wdog_s *curr;
FAR struct wdog_s *prev;
FAR struct wdog_s *next;
int32_t now;
irqstate_t state;
int i;
/* Verify the wdog */
if (!wdog || argc > CONFIG_MAX_WDOGPARMS || delay < 0)
{
set_errno(EINVAL);
return ERROR;
}
/* Check if the watchdog has been started. If so, stop it.
* NOTE: There is a race condition here... the caller may receive
* the watchdog between the time that wd_start is called and
* the critical section is established.
*/
state = irqsave();
if (WDOG_ISACTIVE(wdog))
{
wd_cancel(wdog);
}
/* Save the data in the watchdog structure */
wdog->func = wdentry; /* Function to execute when delay expires */
up_getpicbase(&wdog->picbase);
wdog->argc = argc;
va_start(ap, argc);
for (i = 0; i < argc; i++)
{
wdog->parm[i] = va_arg(ap, uint32_t);
}
#ifdef CONFIG_DEBUG
for (; i < CONFIG_MAX_WDOGPARMS; i++)
{
wdog->parm[i] = 0;
}
#endif
va_end(ap);
/* Calculate delay+1, forcing the delay into a range that we can handle */
if (delay <= 0)
{
delay = 1;
}
else if (++delay <= 0)
{
delay--;
}
#ifdef CONFIG_SCHED_TICKLESS
/* Cancel the interval timer that drives the timing events. This will cause
* wd_timer to be called which update the delay value for the first time
* at the head of the timer list (there is a possibility that it could even
* remove it).
*/
(void)sched_timer_cancel();
#endif
/* Do the easy case first -- when the watchdog timer queue is empty. */
if (g_wdactivelist.head == NULL)
{
/* Add the watchdog to the head == tail of the queue. */
sq_addlast((FAR sq_entry_t*)wdog, &g_wdactivelist);
}
/* There are other active watchdogs in the timer queue */
else
{
now = 0;
prev = curr = (FAR struct wdog_s *)g_wdactivelist.head;
/* Advance to positive time */
while ((now += curr->lag) < 0 && curr->next)
{
prev = curr;
curr = curr->next;
}
/* Advance past shorter delays */
while (now <= delay && curr->next)
{
prev = curr;
curr = curr->next;
now += curr->lag;
}
/* Check if the new wdog must be inserted before the curr. */
if (delay < now)
{
/* The relative delay time is smaller or equal to the current delay
* time, so decrement the current delay time by the new relative
* delay time.
*/
delay -= (now - curr->lag);
curr->lag -= delay;
/* Insert the new watchdog in the list */
if (curr == (FAR struct wdog_s *)g_wdactivelist.head)
{
/* Insert the watchdog at the head of the list */
sq_addfirst((FAR sq_entry_t *)wdog, &g_wdactivelist);
}
else
{
/* Insert the watchdog in mid- or end-of-queue */
sq_addafter((FAR sq_entry_t *)prev, (FAR sq_entry_t *)wdog,
&g_wdactivelist);
}
}
/* The new watchdog delay time is greater than the curr delay time,
* so the new wdog must be inserted after the curr. This only occurs
* if the wdog is to be added to the end of the list.
*/
else
{
delay -= now;
if (!curr->next)
{
sq_addlast((FAR sq_entry_t*)wdog, &g_wdactivelist);
}
else
{
next = curr->next;
next->lag -= delay;
sq_addafter((FAR sq_entry_t*)curr, (FAR sq_entry_t*)wdog,
&g_wdactivelist);
}
}
}
/* Put the lag into the watchdog structure and mark it as active. */
wdog->lag = delay;
WDOG_SETACTIVE(wdog);
#ifdef CONFIG_SCHED_TICKLESS
/* Resume the interval timer that will generate the next interval event.
* If the timer at the head of the list changed, then this will pick that
* new delay.
*/
sched_timer_resume();
#endif
irqrestore(state);
return OK;
}
/****************************************************************************
* Name: wd_timer
*
* Description:
* This function is called from the timer interrupt handler to determine
* if it is time to execute a watchdog function. If so, the watchdog
* function will be executed in the context of the timer interrupt
* handler.
*
* Parameters:
* ticks - If CONFIG_SCHED_TICKLESS is defined then the number of ticks
* in the the interval that just expired is provided. Otherwise,
* this function is called on each timer interrupt and a value of one
* is implicit.
*
* Return Value:
* If CONFIG_SCHED_TICKLESS is defined then the number of ticks for the
* next delay is provided (zero if no delay). Otherwise, this function
* has no returned value.
*
* Assumptions:
* Called from interrupt handler logic with interrupts disabled.
*
****************************************************************************/
#ifdef CONFIG_SCHED_TICKLESS
unsigned int wd_timer(int ticks)
{
FAR struct wdog_s *wdog;
int decr;
/* Check if there are any active watchdogs to process */
while (g_wdactivelist.head && ticks > 0)
{
/* Get the watchdog at the head of the list */
wdog = (FAR struct wdog_s *)g_wdactivelist.head;
#ifndef CONFIG_SCHED_TICKLESS_ALARM
/* There is logic to handle the case where ticks is greater than
* the watchdog lag, but if the scheduling is working properly
* that should never happen.
*/
DEBUGASSERT(ticks <= wdog->lag);
#endif
/* Decrement the lag for this watchdog. */
decr = MIN(wdog->lag, ticks);
/* There are. Decrement the lag counter */
wdog->lag -= decr;
ticks -= ticks;
/* Check if the watchdog at the head of the list is ready to run */
wd_expiration();
}
/* Return the delay for the next watchdog to expire */
return g_wdactivelist.head ?
((FAR struct wdog_s *)g_wdactivelist.head)->lag : 0;
}
#else
void wd_timer(void)
{
/* Check if there are any active watchdogs to process */
if (g_wdactivelist.head)
{
/* There are. Decrement the lag counter */
--(((FAR struct wdog_s *)g_wdactivelist.head)->lag);
/* Check if the watchdog at the head of the list is ready to run */
wd_expiration();
}
}
#endif /* CONFIG_SCHED_TICKLESS */
