templatetimer.c

IXP425的BSP代码

*
* sysAuxClkDisable - turn off auxiliary clock interrupts
*
* This routine disables auxiliary clock interrupts.
*
* RETURNS: N/A
*
* SEE ALSO: sysAuxClkEnable()
*/

void sysAuxClkDisable (void)
    {
    if (sysAuxClkRunning)
        {
	/* TODO - disable auxiliary timer interrupts */

	sysAuxClkRunning = FALSE;
        }
    }

/*******************************************************************************
*
* sysAuxClkEnable - turn on auxiliary clock interrupts
*
* This routine enables auxiliary clock interrupts.
*
* RETURNS: N/A
*
* SEE ALSO: sysAuxClkConnect(), sysAuxClkDisable(), sysAuxClkRateSet()
*/

void sysAuxClkEnable (void)
    {
    static BOOL connected = FALSE;

    if (!connected)
	{
	/* TODO - connect sysAuxClkInt to appropriate interrupt */

	connected = TRUE;
	}

    if (!sysAuxClkRunning)
        {
	/*
	 * TODO - start auxiliary timer interrupts at a
	 * at a frequency of sysAuxClkTicksPerSecond.
	 */

	sysAuxClkRunning = TRUE;
	}
    }

/*******************************************************************************
*
* sysAuxClkRateGet - get the auxiliary clock rate
*
* This routine returns the interrupt rate of the auxiliary clock.
*
* RETURNS: The number of ticks per second of the auxiliary clock.
*
* SEE ALSO: sysAuxClkEnable(), sysAuxClkRateSet()
*/

int sysAuxClkRateGet (void)
    {
    return (sysAuxClkTicksPerSecond);
    }

/*******************************************************************************
*
* sysAuxClkRateSet - set the auxiliary clock rate
*
* This routine sets the interrupt rate of the auxiliary clock.  It does not
* enable auxiliary clock interrupts.
*
* RETURNS: OK, or ERROR if the tick rate is invalid or the timer cannot be set.
*
* SEE ALSO: sysAuxClkEnable(), sysAuxClkRateGet()
*/

STATUS sysAuxClkRateSet
    (
    int ticksPerSecond  /* number of clock interrupts per second */
    )
    {
    if (ticksPerSecond < AUX_CLK_RATE_MIN || ticksPerSecond > AUX_CLK_RATE_MAX)
        return (ERROR);

    /* TODO - return ERROR if rate is not supported */

    if (sysAuxClkRunning)
	{
	sysAuxClkDisable ();
	sysAuxClkEnable ();
	}

    return (OK);
    }

#ifdef  INCLUDE_TIMESTAMP

/*
 * TODO - This is an example timestamp driver.  It must be modified to
 * work with the specific hardware in use.  There is an application note
 * on creating a timestamp driver that is very useful.
 */

/*******************************************************************************
*
* sysTimestampInt - timestamp timer interrupt handler
*
* This rountine handles the timestamp timer interrupt.  A user routine is
* called, if one was connected by sysTimestampConnect().
*
* RETURNS: N/A
*
* SEE ALSO: sysTimestampConnect()
*/

void sysTimestampInt (void)
    {
    if (sysTimestampRunning && sysTimestampRoutine != NULL)
	(*sysTimestampRoutine)(sysTimestampArg);
    }

/*******************************************************************************
*
* sysTimestampConnect - connect a user routine to the timestamp timer interrupt
*
* This routine specifies the user interrupt routine to be called at each
* timestamp timer interrupt.  It does not enable the timestamp timer itself.
*
* RETURNS: OK, or ERROR if sysTimestampInt() interrupt handler is not used.
*/

STATUS sysTimestampConnect
    (
    FUNCPTR routine,    /* routine called at each timestamp timer interrupt */
    int arg     /* argument with which to call routine */
    )
    {
    sysTimestampRoutine = NULL;
    sysTimestampArg = arg;
    sysTimestampRoutine = routine;

    return OK;
    }

/*******************************************************************************
*
* sysTimestampEnable - initialize and enable the timestamp timer
*
* This routine connects the timestamp timer interrupt and initializes the
* counter registers.  If the timestamp timer is already running, this routine
* merely resets the timer counter.
*
* The rate of the timestamp timer should be set explicitly within the BSP,
* in the sysHwInit() routine.  This routine does not intialize the timer
* rate.
*
* RETURNS: OK, or ERROR if hardware cannot be enabled.
*/

STATUS sysTimestampEnable (void)
    {
    static BOOL connected = FALSE;

    if (!connected)
	{
	/* TODO - connect sysTimestampInt to the appropriate interrupt */

	connected = TRUE;
	}

    if (!sysTimestampRunning)
	{
	/* TODO - setup the counter registers and start the counter */

	sysTimestampRunning = TRUE;
	}

    return (OK);
    }

/*******************************************************************************
*
* sysTimestampDisable - disable the timestamp timer
*
* This routine disables the timestamp timer.  Interrupts are not disabled,
* although the tick counter will not increment after the timestamp timer
* is disabled, thus interrupts will no longer be generated.
*
* RETURNS: OK, or ERROR if timer cannot be disabled.
*/

STATUS sysTimestampDisable (void)
    {
    if (sysTimestampRunning)
        sysTimestampRunning = FALSE;

    return (OK);
    }

/*******************************************************************************
*
* sysTimestampPeriod - get the timestamp timer period
*
* This routine returns the period of the timestamp timer in ticks.
* The period, or terminal count, is the number of ticks to which the timestamp
* timer will count before rolling over and restarting the counting process.
*
* RETURNS: The period of the timestamp timer in counter ticks.
*/

UINT32 sysTimestampPeriod (void)
    {
    /* TODO - this is example code, it must be replaced. */

    sysTimestampPeriodValue = TIMESTAMP_HZ / sysClkTicksPerSecond;

    return (sysTimestampPeriodValue);
    }

/*******************************************************************************
*
* sysTimestampFreq - get the timestamp timer clock frequency
*
* This routine returns the frequency of the timer clock, in ticks per second.
*
* RETURNS: The timestamp timer clock frequency, in ticks per second.
*/

UINT32 sysTimestampFreq (void)
    {
    /* TODO - this is example code, it must be replaced. */

    return (TIMESTAMP_HZ);
    }

/*******************************************************************************
*
* sysTimestamp - get the timestamp timer tick count
*
* This routine returns the current value of the timestamp timer tick counter.
* The tick count can be converted to seconds by dividing by the return of
* sysTimestampFreq().
*
* This routine should be called with interrupts locked.  If interrupts are
* not already locked, sysTimestampLock() should be used instead.
*
* RETURNS: The current timestamp timer tick count.
*
* SEE ALSO: sysTimestampLock()
*/

UINT32 sysTimestamp (void)
    {
    UINT32 count = 0;

    /* TODO - read the timestamp timer value */

    return (count);
    }

/*******************************************************************************
*
* sysTimestampLock - get the timestamp timer tick count
*
* This routine returns the current value of the timestamp timer tick counter.
* The tick count can be converted to seconds by dividing by the return of
* sysTimestampFreq().
*
* This routine locks interrupts for cases where it is necessary to stop the
* tick counter in order to read it, or when two independent counters must
* be read.  If interrupts are already locked, sysTimestamp() should be
* used instead.
*
* RETURNS: The current timestamp timer tick count.
*
* SEE ALSO: sysTimestamp()
*/

UINT32 sysTimestampLock (void)
    {
    UINT32 result;
    int oldLevel;

    /*
     * TODO - If interrupt lockout is not needed, then don't do it. Just
     * return the value from sysTimestamp().
     */

    oldLevel = intLock ();

    result = sysTimestamp ();

    intUnlock (oldLevel);

    return (result);
    }

#endif  /* INCLUDE_TIMESTAMP */