sh7615timer.c

IXP425的BSP代码

void sysAuxClkDisable (void)
    {
    if (sysAuxClkRunning)
        {
        /* disable system timer interrupts */

	SH7615TPU_WRITE (TPU_TIER1, 0);

	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)
	{
	UINT16 tmp;

	/* Disable interrupts until it's safe */

	SH7615TPU_WRITE (TPU_TIER1, 0);
	SH7615TPU_READ  (TPU_TSR1, tmp);
	SH7615TPU_WRITE (TPU_TSR1, 0);

	/* Connect handler */

	intConnect (IV_TPU_TGI1A, sysAuxClkInt, 0);

	/* Set AUX clock interrupt priority */
    
	SH7615TPU_READ  (INTC_IPRD, tmp);
	SH7615TPU_WRITE (INTC_IPRD, (tmp & 0xf0ff) | (INT_LVL_AUXCLK << 8));

	connected = TRUE;
	sysAuxClkRunning = FALSE;
	}

    if (!sysAuxClkRunning)
        {
        /* select counter at F/64 , clear with TGRA */

	SH7615TPU_WRITE (TPU_TCR1, TCR_DIVIDE | TCR_TGRA);

	/* set period */

	SH7615TPU_WRITE (TPU_TGR1A, (TICK_FREQ / sysAuxClkTicksPerSecond));

	/* Reset counter */

	SH7615TPU_WRITE (TPU_TCNT1, 0);

	/* enable interrupt */

	SH7615TPU_WRITE (TPU_TIER1, TIER_TGIEA);

	/* start counter */

	SH7615TPU_SET (TPU_TSTR, TSTR_CST1);

	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);

    sysAuxClkTicksPerSecond = ticksPerSecond;

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

    return (OK);
    }

#ifdef  INCLUDE_TIMESTAMP

/*******************************************************************************
*
* 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)
    {
    UINT8 value;

    if (SH7615TPU_READ (TPU_TSR2, value), (value & TSR_TGFA) == TSR_TGFA)
	{
	/* clear the interrupt */

        SH7615TPU_WRITE (TPU_TSR2, (value & ~TSR_TGFA));

        /* call system clock service routine */

        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;		/* set to NULL to avoid calling old */
					/* routine with new argument */

    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)
	{
	UINT16 tmp;

	/* Disable interrupts until it's safe */

	SH7615TPU_WRITE (TPU_TIER2, 0);
	SH7615TPU_READ  (TPU_TSR2, tmp);
	SH7615TPU_WRITE (TPU_TSR2, 0);

	/* connect sysTimestamp to the appropriate interrupt */

	if (intConnect(IV_TPU_TGI2A, sysTimestampInt, 0) != OK)
	    return (ERROR);

	/* Set timestamp interrupt priority */
    
	SH7615TPU_READ  (INTC_IPRD, tmp);
	SH7615TPU_WRITE (INTC_IPRD, (tmp & 0xff0f) | (INT_LVL_TSTAMP << 4));

	connected = TRUE;
	}

    if (!sysTimestampRunning)
	{
        /* select counter at F/64 , clear with TGRA */

	SH7615TPU_WRITE (TPU_TCR2, TCR_DIVIDE | TCR_TGRA);

	/* set rate */

	SH7615TPU_WRITE (TPU_TGR2A, 0xffff);

	/* Reset counter */

	SH7615TPU_WRITE (TPU_TCNT2, 0);

        /* enable interrupt */

        SH7615TPU_WRITE (TPU_TIER2, TIER_TGIEA);

        /* start counter */
	
	SH7615TPU_SET (TPU_TSTR, TSTR_CST2);

	sysTimestampRunning = TRUE;
	}

    return (OK);
    }

/*******************************************************************************
*
* sysTimestampDisable - disable the timestamp timer
*
* This routine disables the timestamp timer.  
*
* RETURNS: OK, or ERROR if timer cannot be disabled.
*/

STATUS sysTimestampDisable (void)
    {
    if (sysTimestampRunning)
        {
	/* Stop timer */

	SH7615TPU_CLEAR (TPU_TSTR, TSTR_CST2);

        /* disable system timer interrupts */

        SH7615TPU_WRITE (TPU_TIER2, 0);

        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)
    {
    return (UINT32)(0xffff);        /* highest period -> freerunning */
    }

/*******************************************************************************
*
* 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)
    {
    return (UINT32)(TICK_FREQ);
    }

/*******************************************************************************
*
* 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)
    {
    UINT16 result;
    SH7615TPU_READ (TPU_TCNT2, result);
    return (UINT32) result;
    }

/*******************************************************************************
*
* 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)
    {
    UINT16 result;
    SH7615TPU_READ (TPU_TCNT2, result);
    return (UINT32) result;
    }

#endif  /* INCLUDE_TIMESTAMP */