s3c2510timer.c

S3c2510下的VXWORKS的BSP源代码（包括了以太网、串口、USB等等驱动）

}

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

void sysAuxClkDisable(void)
{
    if (sysAuxClkRunning)
    {
        /* Disable timer. */
        *S3C2510_TMOD &= ~S3C2510_TMOD_TE4;

        sysAuxClkRunning = FALSE;
    }
}

/*******************************************************************************
*
* sysAuxClkEnable - turn on auxiliary clock interrupts
*
* This routine enables auxiliary clock interrupts. The timer is used in
* "reference mode" i.e. a value is programmed into the reference register and an
* interrupt occurs when the timer reaches that value. 
*
* RETURNS: N/A
*
* SEE ALSO: sysAuxClkConnect(), sysAuxClkDisable(), sysAuxClkRateSet()
*/

void sysAuxClkEnable(void)
{
    if (!sysAuxClkRunning)
    {
        /* Calculate the timer interval. */
        *S3C2510_TDATA4 = SPLL_FREQ * 1000 * 1000 / sysAuxClkTicksPerSecond - 1;

        /* Enable timer. */
        *S3C2510_TMOD |= S3C2510_TMOD_TE4;

        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 < SYS_CLK_RATE_MIN) || (ticksPerSecond > SYS_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)
{
    /* Clear interrupt. */
    *S3C2510_TIC |= S3C2510_TIC_T3;

    /* Call timestamp timer service routine. */
    if (sysTimestampRoutine && sysTimestampRunning)
    {
        (*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 to timestamp timer interrupt routine */
    )
{
    if (sysTimestampConnectFirstTime)
    {
        /* Enable peripheral clock. */
        *S3C2510_PCLKDIS &= ~S3C2510_PCLKDIS_TIMER3;

        /* Interval mode. */
        *S3C2510_TMOD &= ~S3C2510_TMOD_TMD3;

        /* Connect and enable interrupt. */
        intConnect(INT_VEC_TIMER3, (VOIDFUNCPTR)sysTimestampInt, 0);
        intEnable(INT_LVL_TIMER3);

        sysTimestampConnectFirstTime = FALSE;
    }

    sysTimestampRoutine = routine;
    sysTimestampArg     = arg;

    return OK;
}

/*******************************************************************************
*
* sysTimestampDisable - turn off auxiliary clock interrupts
*
* This routine disables auxiliary clock interrupts.
*
* RETURNS: OK, always
*
* SEE ALSO: sysTimestampEnable()
*/

STATUS sysTimestampDisable(void)
{
    if (sysTimestampRunning)
    {
        /* Disable timer. */
        *S3C2510_TMOD &= ~S3C2510_TMOD_TE3;

        sysTimestampRunning = FALSE;
    }

    return OK;
}

/*******************************************************************************
*
* sysTimestampEnable - initialize and enable the timestamp timer
*
* This routine connects interrupts, and enables the timer device
*
* RETURNS: TRUE always
*/

STATUS sysTimestampEnable(void)
{
    if (!sysTimestampRunning)
    {
        /* Calculate the timer interval. */
        *S3C2510_TDATA3 = SPLL_FREQ * 1000 * 1000 / DEF_SYS_TIMESTAMP_TICKS - 1;

        /* Enable timer. */
        *S3C2510_TMOD |= S3C2510_TMOD_TE3;

        sysTimestampRunning = TRUE;
    }

    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)
{
    /* The period of the timestamp depends on the clock rate of the on-chip timer. */

    return (*S3C2510_TDATA3);
}

/*******************************************************************************
*
* 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 (SPLL_FREQ * 1000 * 1000);
}

/*******************************************************************************
*
* 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 (*S3C2510_TCNT3);
}

/*******************************************************************************
*
* 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 (*S3C2510_TCNT3);
}
#endif  /* INCLUDE_TIMESTAMP */