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/* mpc8240AuxClk.c - Mpc8240 EPIC Timer (Aux Clk) library */ 
 
/* Copyright 1999-2000 Wind River Systems, Inc. */ 
/* Copyright 1999-2000 Motorola, Inc. All Rights Reserved */ 
  
/* 
modification history 
-------------------- 
01a,28feb00,rhk  created from version 01e, MV2100 BSP. 
*/ 
  
/* 
DESCRIPTION 
This timer contains routines to use timer 0 on the EPIC as the auxiliary 
clock. 
*/ 
 
 
/* includes */ 
 
#include "prpmc600.h" 
 
/* defines */ 
 
#define EPIC_TIMER_CNT	(DEC_CLOCK_FREQ / 8) 
 
/* locals */ 
 
LOCAL void    sysAuxClkInt (); 
LOCAL STATUS  sysAuxClkInit(); 
LOCAL FUNCPTR sysAuxClkRoutine        = NULL; 
LOCAL int     sysAuxClkArg            = NULL; 
LOCAL int     sysAuxClkTicksPerSecond = 100; 
LOCAL BOOL    sysAuxClkConnected      = FALSE; 
LOCAL int     sysAuxClkRunning        = FALSE; 
 
/* externals */ 
 
IMPORT void   sysPciOutLong (UINT32, UINT32); 
 
/****************************************************************************** 
* 
* sysAuxClkInt - handle an auxiliary clock interrupt from EPIC timer 0 
* 
* This routine handles a EPIC timer 0 interrupt.  It clears the interrupt 
* and calls the routine installed by sysAuxClkConnect(). 
* 
* RETURNS: N/A 
*/ 
  
LOCAL void sysAuxClkInt (void) 
    { 
    if (sysAuxClkRoutine != NULL) 
 	(*sysAuxClkRoutine) (sysAuxClkArg); 
    } 
  
 
/***************************************************************************** 
* 
* sysAuxClkInit - mpc8240 aux. clock initialization routine 
* 
* This routine should be called before calling any other routine in this 
* module. 
* 
* RETURNS: OK, or ERROR. 
*/ 
  
STATUS sysAuxClkInit (void) 
    { 
    /* disable counter */ 
 
    sysPciOutLong ((UINT32)EPIC_TIMER0_BASE_CT_REG, (0xffffffff) ); 
    SYNC;					/* synchronize */ 
    
    /* setup timer frequency register */ 
 
    sysPciOutLong ((UINT32)EPIC_TIMER_FREQ_REG, (UINT32)EPIC_TIMER_CNT); 
    
    /* interrupt unmasked, priority level 15, vector TIMER0_INT_VEC. */ 
 
    sysPciOutLong ((UINT32)EPIC_TIMER0_VEC_PRI_REG,  
                  (( EPIC_GTVP_PRI_15 | (TIMER0_INT_VEC) ) & ~EPIC_GTVP_M)); 
    
    /* interrupt directed at processor 0 */ 
 
    sysPciOutLong ((UINT32)EPIC_TIMER0_DEST_REG, EPIC_GTD_P0); 
 
    SYNC;					/* synchronize */ 
    
    sysAuxClkRunning = FALSE; 
    
    return (OK); 
    } 
 
 
/****************************************************************************** 
* 
* sysAuxClkConnect - connect a routine to the auxiliary clock interrupt 
* 
* This routine specifies the interrupt service routine to be called at each 
* auxiliary clock interrupt. 
* 
* RETURNS: OK, or ERROR if the routine cannot be connected to the interrupt. 
* 
* SEE ALSO: intConnect(), sysAuxClkEnable() 
*/ 
  
STATUS sysAuxClkConnect 
    ( 
    FUNCPTR routine,    /* routine called at each aux clock interrupt */ 
    int arg             /* argument with which to call routine        */ 
    ) 
    { 
    sysAuxClkRoutine	= routine; 
    sysAuxClkArg	= arg; 
    sysAuxClkConnected	= TRUE; 
  
    return (OK); 
    } 
  
 
/****************************************************************************** 
* 
* sysAuxClkDisable - turn off auxiliary clock interrupts 
* 
* This routine disables auxiliary clock interrupts. 
* 
* RETURNS: N/A 
* 
* SEE ALSO: sysAuxClkEnable() 
*/ 
  
void sysAuxClkDisable (void) 
    { 
    if (sysAuxClkRunning) 
        { 
        /* disable counter */ 
 
	sysPciOutLong ((UINT32)EPIC_TIMER0_BASE_CT_REG, 0xffffffff); 
	SYNC;					/* synchronize */ 
         
        sysAuxClkRunning = FALSE; 
        } 
    } 
 
 
/****************************************************************************** 
* 
* sysAuxClkEnable - turn on auxiliary clock interrupts 
* 
* This routine enables auxiliary clock interrupts. 
* 
* RETURNS: N/A 
* 
* SEE ALSO: sysAuxClkDisable() 
*/ 
  
void sysAuxClkEnable (void) 
    { 
    if (!sysAuxClkRunning) 
	{ 
	/* enable counter and write value to count from */ 
 
	sysPciOutLong ((UINT32)EPIC_TIMER0_BASE_CT_REG, 
	               ((EPIC_TIMER_CNT/sysAuxClkTicksPerSecond) &  
		       EPIC_GTBC_C_MASK)); 
	SYNC;					/* synchronize */ 
	   
	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 is not 
* supported, since the auxiliary clock always runs at the same rate as the 
* system clock. 
* 
* RETURNS: OK or ERROR. 
* 
* 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); 
    }