sun4timer.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)
        {
        *SUN_IR         &= ~IR_ALL;     /* turn off interrupts */
        *SUN_IR         &= ~IR_CLOCK14; /* turn off lvl 14 */
        *SUN_IR         |= IR_ALL;      /* turn on interrupts */
        sysAuxClkRunning = FALSE;
        }
    }

/***************************************************************************
*
* sysAuxClkEnable - turn on auxiliary clock interrupts
*
* This routine enables auxiliary clock interrupts.  
*
* NOTE: The auxilliary clock and the timestamp clock are mutually
* exclusive.  The timestamp clock cannot be used if the auxilliary clock
* is running.
*
* RETURNS: N/A
*
* SEE ALSO: sysAuxClkDisable()
*/

void sysAuxClkEnable (void)

    {
    unsigned int intRegister;

    if (! sysAuxClkRunning && ! sysTimestampRunning)
        {
        *SUN_IR         &= ~IR_ALL;     /* turn off interrupts */
        intRegister = *SUN_LIMIT_1;     /* Clear interrupt at clock */
        *SUN_IR         &= ~IR_CLOCK14; /* Clear interrupt pending */
        *SUN_IR         |= IR_CLOCK14;  /* turn on lvl 14 */
        *SUN_IR         |= IR_ALL;      /* turn on interrupts */
        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 (auxClkTicksPerSecond);
    }

/***************************************************************************
*
* 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);

    auxClkTicksPerSecond = ticksPerSecond;
    *SUN_COUNTER_1 = 0;
    *SUN_LIMIT_1 = (1000000 / ticksPerSecond) << 10;
    *SUN_COUNTER_1 = 0;
    return (OK);
    }

#ifdef  INCLUDE_TIMESTAMP

/*******************************************************************************
*
* sysTimestampConnect - connect a user routine to a timestamp timer interrupt
*
* This routine specifies the user interrupt routine to be called at each
* timestamp timer interrupt.  
*
* NOTE: The auxilliary clock and the timestamp clock are mutually
* exclusive.  The timestamp clock cannot be used if the auxilliary clock
* is running.
*
* RETURNS: OK, or ERROR if the auxiliary clock is in use.
*
* SEE ALSO: sysTimestampEnable()
*/

STATUS sysTimestampConnect
    (
    FUNCPTR routine,    /* routine called at each timestamp timer interrupt */
    int arg             /* argument with which to call routine */
    )
    {
    if (sysAuxClkRunning)
	return ERROR;

    sysTimestampRoutine = routine;
    sysTimestampArg = arg;

    return (OK);
    }

/*******************************************************************************
*
* sysTimestampEnable - enable a timestamp timer interrupt
*
* This routine enables timestamp timer interrupts and resets the counter.
*
* NOTE: The auxilliary clock and the timestamp clock are mutually
* exclusive.  The timestamp clock cannot be used if the auxilliary clock
* is running.
*
* RETURNS: OK, or ERROR if the timestamp timer cannot be enabled.
*
* SEE ALSO: sysTimestampDisable()
*/

STATUS sysTimestampEnable (void)
    {
    unsigned int intRegister;

    if (sysAuxClkRunning)
        return (ERROR);

    if (! sysTimestampRunning)
        {
        *SUN_IR         &= ~IR_ALL;     /* turn off interrupts */

        *SUN_COUNTER_1 = 0;
        *SUN_LIMIT_1 = 0x1fffff << 10;  	/* 0 limit means free running */
        *SUN_COUNTER_1 = 0;

        intRegister = *SUN_LIMIT_1;     /* Clear interrupt at clock */
        *SUN_IR         &= ~IR_CLOCK14; /* Clear interrupt pending */
        *SUN_IR         |= IR_CLOCK14;  /* turn on lvl 14 */

        *SUN_IR         |= IR_ALL;      /* turn on interrupts */

        *SUN_COUNTER_1 = 0;
        *SUN_LIMIT_1 = 0x1fffff << 10;  	/* 0 limit means free running */
        *SUN_COUNTER_1 = 0;

        sysTimestampRunning = TRUE;
        }

    return (OK);
    }

/*******************************************************************************
*
* sysTimestampDisable - disable a timestamp timer interrupt
*
* This routine disables the timestamp timer.  It does not directly disable
* interrupts.  However, the tick counter does not increment once the 
* timestamp timer is disabled, thus, interrupts are no longer generated.
* This routine merely resets the timer counter.
*
* RETURNS: OK, always.
*
* SEE ALSO: sysTimestampEnable()
*/

STATUS sysTimestampDisable (void)
    {
    if (sysTimestampRunning)
        {
	*SUN_LIMIT_1 = 0x80000000 ;          /* 0 limit means free running */

        *SUN_IR         &= ~IR_ALL;     /* turn off interrupts */
        *SUN_IR         &= ~IR_CLOCK14; /* turn off lvl 14 */
        *SUN_IR         |= IR_ALL;      /* turn on interrupts */
        sysTimestampRunning = FALSE;
        }

    return (OK);
    }

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

UINT32 sysTimestampPeriod (void)
    {
    return (0x1fffff);        /* highest period -> freerunning */
    }

/*******************************************************************************
*
* sysTimestampFreq - get a timestamp timer clock frequency
*
* This routine gets the frequency of the timer clock, in ticks per 
* second.  The rate of the timestamp timer is set explicitly by the 
* hardware and typically cannot be altered.
*
* RETURNS: The timestamp timer clock frequency, in ticks per second.
*/

UINT32 sysTimestampFreq (void)
    {
    return ((UINT32) 1000000);
    }

/*******************************************************************************
*
* sysTimestamp - get a 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 it by the return of
* sysTimestampFreq().
*
* This routine should be called with interrupts locked.  If interrupts are
* not locked, sysTimestampLock() should be used instead.
*
* RETURNS: The current timestamp timer tick count.
*
* SEE ALSO: sysTimestampFreq(), sysTimestampLock()
*/

UINT32 sysTimestamp (void)
    {
    return (*((UINT32 *) SUN_COUNTER_1) >> 10);
    }

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

UINT32 sysTimestampLock (void)
    {
    return (*((UINT32 *) SUN_COUNTER_1) >> 10);
    }

#endif /* INCLUDE_TIMESTAMP */