ixp425timer.c

INTEL IXP425的VXWORKS BSP

/* ixp425Timer.c - ixp425 processor timer library */

/* Copyright 2002 Wind River Systems, Inc. */

#include "copyright_wrs.h"

/*
modification history
--------------------
01b,05dec02,jb  Fixed timestamp and aux clock
01a,05jun02,jb  initial version...
*/

/*
DESCRIPTION
This library contains routines to manipulate the timer functions.

			_______
hardware		TIMER 0
clock			_______
			   |
interface -----------------------------------------------------
		|		  |		     |
		|		  |		     |
software     _______		______		_____________
clock(s)     sysClk		auxClk		timeStampClk
	     _______		______		_____________


interface functions:

clkInt() - clock interrupt handler
clkConnect() - connect a routine to the clock interrupt
clkDisable() - turn off system clock interrupts
clkEnable() - turn on system clock interrupts
clkRateGet() - get the system clock rate oscillations per second
clkPeriod() - get the period of the timer (tick counter rollover)
clkFreq() - get a timer clock frequency
clkTimestamp() - get a tick counter count

Note: There are two different types of ticks referred to.  The frequency
tick and the counter tick.  A frequency tick refers to the timer clock
oscillations per second and the counter ticks refer to the number of times
(ticks) a register decreases until roll over.

The macros SYS_CLK_RATE_MIN, SYS_CLK_RATE_MAX must be defined to
provide parameter checking for the sysClkRateSet() routine.

*/

#include "ixp425.h"
#include "ixp425Timer.h"
#include "drv/timer/timerDev.h"

#ifdef INCLUDE_TIMESTAMP
#include "drv/timer/timestampDev.h"
#endif

/* 
 * The APB timer block is not based on the CPU speed, but on
 * the APB core clock of 66Mhz.
 */


#define TIMER_APB_CLOCK_MHZ ( IXP425_PERIPHERAL_BUS_CLOCK )

/* hardware access methods */

#ifndef IXP425_REG_TIMER_READ
#define IXP425_REG_TIMER_READ(reg,result) \
	((result) = *(volatile UINT32 *)(reg))
#endif /*IXP425_REG_TIMER_READ*/

#ifndef IXP425_REG_TIMER_WRITE
#define IXP425_REG_TIMER_WRITE(reg,data) \
	(*((volatile UINT32 *)(reg)) = (data))
#endif /*IXP425_REG_TIMER_WRITE*/


/* Locals */

LOCAL int     clockTicksPerSecond   = IXP425_OSST_TICKS_PER_SECOND;
LOCAL UINT32  clockTimerRollOver    = IXP425_OSST_ROLLOVER;

LOCAL BOOL    clockConnected	    = FALSE;

LOCAL BOOL    sysClkRunning	    = FALSE;
LOCAL void    sysClkDummyRoutine(int arg) {}
LOCAL FUNCPTR sysClkRoutine	    = (FUNCPTR) sysClkDummyRoutine;
LOCAL int     sysClkArg		    = (int) NULL;
LOCAL BOOL    sysClkConnected	    = FALSE;

LOCAL BOOL    sysAuxClkRunning	    = FALSE;
LOCAL void    sysAuxClkDummyRoutine(int arg) {}
LOCAL FUNCPTR sysAuxClkRoutine	    = (FUNCPTR)sysAuxClkDummyRoutine;
LOCAL int     sysAuxClkArg	    = (int) NULL;
LOCAL BOOL    sysAuxClkConnected    = FALSE;
LOCAL int     sysAuxClkTicksPerSecond = 100;
LOCAL int     sysAuxClkRollOver     = ((TIMER_APB_CLOCK_MHZ * 0x100000) / 100);

#ifdef INCLUDE_TIMESTAMP
LOCAL BOOL    sysTimestampRunning   = FALSE;
LOCAL FUNCPTR sysTimestampRoutine   = (FUNCPTR) NULL;
LOCAL int     sysTimestampArg       = (int) NULL;
#endif




LOCAL void clkInt (void)
{
     /* Clear Pending Interrupt by writing '1' to it */
     IXP425_REG_TIMER_WRITE(IXP425_OSST, IXP425_OSST_TIMER_1_PEND);

     if (sysClkRunning)
	 (*(FUNCPTR) sysClkRoutine) (sysClkArg);


     /* The timer is free running and as such it has already reloaded
      * and is counting down 
      */
}

/***************************************************************************
*
* clkConnect - connect a routine to the clock interrupt
*
* This routine specifies the interrupt service routine to be called at each
* clock interrupt.
*
* RETURN: OK
*
* SEE ALSO: intConnect(), usrClock(), clkEnable()
*/

LOCAL STATUS clkConnect (void)
    {
    if(!clockConnected)
	{
	 sysHwInit2 ();
	 (void)intConnect ((void *)INT_VEC_TIMER1, clkInt, 0);
	 clockConnected = TRUE;
	}

    return (OK);
    }

/***************************************************************************
*
* clkDisable - turn off system clock interrupts
*
* This routine disables clock interrupts.  In order for the hardware clock
* to be disables all the software clocks must be disabled.
*
* RETURNS: N/A
*
* SEE ALSO: clkEnable()
*/

LOCAL void clkDisable (void)
    {
	
	intDisable(INT_VEC_TIMER1);
	/* Clear the OST register for this timer, This disabled the
	   timer */
	IXP425_REG_TIMER_WRITE( IXP425_OSRT1 , IXP425_OST_DISABLED );
    
    }


/***************************************************************************
*
* clkEnable - turn on system clock interrupts
*
* This routine enables system clock interrupts.	 Any software clock can
* enable the hardware clock
*
* RETURNS: N/A
*
* SEE ALSO: sysClkDisable(), sysClkRateSet()
*/

LOCAL void clkEnable (void)
    {
	
	IXP425_REG_TIMER_WRITE( IXP425_OSRT1 , ((clockTimerRollOver & ~IXP425_OST_RELOAD_MASK) |  IXP425_OST_ENABLE )  );

	intEnable(INT_VEC_TIMER1);
    }

/***************************************************************************
*
* clkRateGet - get the system clock rate
*
* This routine returns the oscillations clock rate.
*
* RETURNS: The number of oscillations per second of the clock.
*
* SEE ALSO: sysClkEnable(), sysClkRateSet()
*/

LOCAL int clkRateGet (void)
    {
    return (clockTicksPerSecond);
    }

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

LOCAL UINT32 clkPeriod (void)
    {
    return (clockTimerRollOver);
    }

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

LOCAL UINT32 clkFreq (void)
    {
    return ( TIMER_APB_CLOCK_MHZ * 0x100000);
    }

/**************************************************************************
*
* clkTimestamp - get a time stamp count
*
* This routine returns the current value of the timer tick counter.
* The tick count can be converted to seconds by dividing it by the return of
* clkFreq().
*
*
* RETURNS: The current time stamp count.
*
* SEE ALSO: clkFreq()
*/

LOCAL UINT32 clkTimestamp (void)
    {

	UINT32 count;

	/* Read the free running up-timer from peripherial block */

	IXP425_REG_TIMER_READ(IXP425_OSTS,count);
	return(count);
    }

   

/***************************************************************************
*
* sysClkConnect - connect a routine to the system clock interrupt
*
* This routine specifies the interrupt service routine to be called at each
* clock interrupt.  Normally it is called from usrRoot() in usrConfig.c to
* connect usrClock() to the system clock interrupt.
*
* RETURN: OK
*
* SEE ALSO: intConnect(), usrClock(), sysClkEnable()
*/

STATUS sysClkConnect
    (
    FUNCPTR routine,	/* routine called at each system clock interrupt */
    int	    arg		/* argument with which to call routine		 */
    )
    {
    sysClkConnected   = TRUE;
    sysClkRoutine     = routine;
    sysClkArg	      = arg;

    clkConnect();

    return (OK);
    }

/***************************************************************************
*
* sysClkDisable - turn off system clock interrupts
*
* This routine disables system clock interrupts.
*
* RETURNS: N/A
*
* SEE ALSO: sysClkEnable()
*/

void sysClkDisable (void)
    {
    if (sysClkRunning)
	{
	clkDisable();

	sysClkRunning	 = FALSE;
	}
    }

/***************************************************************************
*
* sysClkEnable - turn on system clock interrupts
*
* This routine enables system clock interrupts.
*
* RETURNS: N/A
*
* SEE ALSO: sysClkDisable(), sysClkRateSet()
*/

void sysClkEnable (void)
    {
    if (!sysClkRunning)
	{
	clkEnable();

	sysClkRunning	 = TRUE;
	}
    }

/***************************************************************************
*
* sysClkRateGet - get the system clock rate
*
* This routine returns the system clock rate.
*
* RETURNS: The number of ticks per second of the system clock.
*
* SEE ALSO: sysClkEnable(), sysClkRateSet()
*/

int sysClkRateGet (void)
    {
    return(clkRateGet());
    }

/***************************************************************************
*
* sysClkRateSet - set the system clock rate
*
* This routine sets the interrupt rate of the system clock.  It is called by
* usrRoot() in usrConfig.c.
*
* RETURNS: OK, or ERROR if the tick rate is invalid or the timer cannot be set.
*
* SEE ALSO: sysClkEnable(), sysClkRateGet()
*/

STATUS sysClkRateSet
    (
    int ticksPerSecond	    /* number of clock interrupts per second */
    )
    {
    if (ticksPerSecond < SYS_CLK_RATE_MIN || ticksPerSecond > SYS_CLK_RATE_MAX)
        return (ERROR);

    clockTicksPerSecond = ticksPerSecond;
    clockTimerRollOver = ((TIMER_APB_CLOCK_MHZ * 0x100000)
                          / clockTicksPerSecond);

    if (sysClkRunning)
	{
	sysClkDisable ();
	sysClkEnable ();
	}

    return (OK);
    }

/*******************************************************************************
*
* sysAuxClkInt - handle an auxiliary clock interrupt