/* sngks32cIntrCtl.c - Samsung KS32C interrupt controller driver */


/* Copyright 1984-2001 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
modification history
--------------------
01o,23jul04,a_m  BSP定制 for 多刃劍開發板
01c,02oct01,m_h  race condition
01b,26apr01,m_h  convert tabs to spaces for readability
01a,12apr01,m_h  created from snds100 template.
*/

/*

DESCRIPTION

This module implements interrupt controller driver for Samsung's KS32C50100
microprocessor which is an ARM based processor with several integrated 
peripherals.  It has an interrupt controller, two 32-bit timers, one 
Ethernet controller, two HDLC controllers, one IIC controller, general 
purpose I/O ports, and a 2-channel DMA controller.

The KS32C interrupt controller is a simple, generic interrupt controller
that manages 21 levels of interrupts from various sources internal to the
microprocessor and external to it.  For external interrupts are supported.
The interrupt controller has control and pending status registers, mask
register and supports level-sensitive interrupts.  This library provides
the routines to manage interrupts multiplexed by the KS32C interrupt controller.

The KS32C interrupt controller registers used by this driver are described
below under the symbolic names used herein.

SNGKS32C_INTENB (write): this is the mask register described in the
KS32C50100 Users' Manual.  When this register is written, each data bit 
that is clear (0) causes the corresponding interrupt to be enabled.
Each bit that is set (1) causes the corresponding interrupt to be disabled.

SNGKS32C_INTPEND (read): this is the interrupt pending register.
When this register is read, each data bit that is set (1) indicates that
an interrupt is pending from the corresponding source. Level 20 is the
highest priority and level 0 is the lowest.

SNGKS32C_INTMODE (write): this register is used to configure the interrupts
in FIQ or IRQ mode.  Each bit set in this register configures the corresponding
interrupt as FIQ.  Otherwise the interrupt is treated as IRQ.  VxWorks
does not support the high priority FIQ mode of interrupts.  Hence all the
interrupts have to be configured in IRQ mode.

The interrupt priority registers can be used to change the priorities
of the interrupts from the default settings.  This feature is not
supported in this driver.  All the interrupts are set with the default
priority ordering.

The number of interrupts supported by the device i.e. the number of
valid bits in the SNGKS32C_INTPEND register (21), is specified by
SNGKS32C_INTNUMLEVELS.

sngks32carm7.h has defined the addresses of the controller chips registers:
SNGKS32C_INTENB, SNGKS32C_INTDIS and SNGKS32C_INTPEND and also the 
driver constants SNGKS32C_INTMASK_VAL, SNGKS32C_INTNUMLEVELS.

The chip registers are memory-mapped at specified addresses internal to
the processor.  32-bit accesses can be made to these register locations.
The macros SNGKS32C_INT_REG_READ and SNGKS32C_INT_REG_WRITE are used to
access these registers.

The BSP will initialize this driver in sysHwInit2(), after initializing
the main interrupt library, usually intLibInit().  The initialization
routine, sngks32cIntDevInit() will setup the interrupt controller device,
it will mask off all individual interrupt sources and then set the
interrupt level to enable all interrupts.  See sngks32cIntDevInit for more
information.

All of the functions in this library are global.  This allows them to
be used by the BSP if it is necessary to create wrapper routines or to
incorporate several drivers together as one.

SEE ALSO
<Samsung KS32C50100 User's Manual>

*/

#include "vxWorks.h"
#include "config.h"
#include "intLib.h"

#include "s3c44b0x.h"	/*  : modified */

#if !defined (S3C44B0X_INTPEND) || !defined (S3C44B0X_INTENB) || \
    !defined (S3C44B0X_INTMASK_VAL) || !defined (S3C44B0X_INTNUMLEVELS) || \
    !defined (S3C44B0X_INTDIS)
#   error missing S3C44B0X interrupt definitions
#endif

#define SNGKS32C_INT_VEC_BASE    (0x0)

/* hardware access methods */
#ifndef SNGKS32C_INT_REG_READ
#   define SNGKS32C_INT_REG_READ(x,result) \
        ((result) = *(volatile UINT32 *)(x))
#endif    /*SNGKS32C_INT_REG_READ*/

#ifndef SNGKS32C_INT_REG_WRITE
#   define SNGKS32C_INT_REG_WRITE(x,data) \
        (*((volatile UINT32 *)(x)) = (data))
#endif /*SNGKS32C_INT_REG_WRITE*/


/* Convert level number to vector number */

#ifndef SNGKS32C_INT_LVL_VEC_MAP
#   define SNGKS32C_INT_LVL_VEC_MAP(level, vector) \
        ((vector) = ((level) + SNGKS32C_INT_VEC_BASE))
#endif

/* Convert pending register value, to a level number */

#ifndef SNGKS32C_INT_PEND_LVL_MAP
#   define SNGKS32C_INT_PEND_LVL_MAP(pendReg, level) \
        ((level) = (pendReg))
#endif


/* driver constants */

#define SNGKS32C_INT_ALL_ENABLED     (S3C44B0X_INTNUMLEVELS)
#define SNGKS32C_INT_ALL_DISABLED    (S3C44B0X_INTNUMLEVELS-1)


/* Local data */

/*
 * A mask word.  Bits are set in this word when a specific level
 * is enabled. It is used to mask off individual levels that have
 * not been explicitly enabled.
 */

LOCAL UINT32 sngks32cIntLvlEnabled;

/* forward declarations */

STATUS    sngks32cIntLvlVecChk  (int*, int*);
STATUS    sngks32cIntLvlEnable  (int);
STATUS    sngks32cIntLvlDisable (int);

/*  : 中斷確認 */
STATUS s3c44BIntLvlAck (int level, int vector)
{
	SNGKS32C_INT_REG_WRITE(S3C44B0X_I_ISPC,(1 << vector));

	return OK;
}

/*******************************************************************************
*
* sngks32cIntDevInit - initialize the interrupt controller
*
* This routine will initialize the interrupt controller device, disabling all
* interrupt sources.  It will also connect the device driver specific routines
* into the architecture level hooks.  If the BSP needs to create a wrapper
* routine around any of the arhitecture level routines, it should install the
* pointer to the wrapper routine after calling this routine.
*
* RETURNS: N/A
*/

void sngks32cIntDevInit (void)
    {
    /* install the driver routines in the architecture hooks */

    sysIntLvlVecChkRtn     = sngks32cIntLvlVecChk;
    sysIntLvlEnableRtn     = sngks32cIntLvlEnable;
    sysIntLvlDisableRtn    = sngks32cIntLvlDisable;
	
	sysIntLvlVecAckRtn     = s3c44BIntLvlAck;  			/*  : added */
	
    sngks32cIntLvlEnabled  = 0x0;     /* all sources disabled */
    SNGKS32C_INT_REG_WRITE (S3C44B0X_INTCON, 5);		/*  : added */
	/*  : modified */
    SNGKS32C_INT_REG_WRITE (S3C44B0X_INTENB, ((~sngks32cIntLvlEnabled) & S3C44B0X_INTMASK_VAL));
    /*SNGKS32C_INT_REG_WRITE (SNGKS32C_INTPEND, SNGKS32C_INTMASK_VAL);*/
    /*SNGKS32C_INT_REG_WRITE (SNGKS32C_INTPEND, 0);*/	/*  : deleted */
	SNGKS32C_INT_REG_WRITE (S3C44B0X_I_ISPC, S3C44B0X_INTMASK_VAL);	/*  : added */
    SNGKS32C_INT_REG_WRITE (S3C44B0X_INTMODE,S3C44B0X_INTMODEIRQ);
    }

/*******************************************************************************
*
* sngks32cIntLvlVecChk - check for and return any pending interrupts
*
* This routine interrogates the hardware to determine the highest priority
* interrupt pending.  It returns the vector associated with that interrupt, and
* also the interrupt priority level prior to the interrupt (not the
* level of the interrupt).  The current interrupt priority level is then
* raised to the level of the current interrupt so that only higher priority
* interrupts will be accepted until this interrupt is finished.
*
* The return value ERROR indicates that no pending interrupt was found and
* that the level and vector values were not returned.
*
* RETURNS: OK or ERROR if no interrupt is pending.
*/

STATUS  sngks32cIntLvlVecChk
    (
    int* pLevel,  /* ptr to receive old interrupt level */
    int* pVector  /* ptr to receive current interrupt vector */
    )
    {
    int newLevel;
    int intPendMask = 0x2000000;	/*  : 0x100000->0x2000000 */
    int count;
    UINT32 isr;
	int intMask;					/*  : added */
	
    /* Read pending interrupt register and mask undefined bits */

    SNGKS32C_INT_REG_READ (S3C44B0X_INTPEND, newLevel);

    if ((newLevel & S3C44B0X_INTMASK_VAL) == 0)
        return ERROR;

	/*  : added */
	SNGKS32C_INT_REG_READ (S3C44B0X_INTENB, intMask);
	newLevel = newLevel&(~intMask);
	if (newLevel == 0) return ERROR;
	
    /*
     * Step through the bits looking for a 1. This *will* terminate.
     * We could use ffsLsb() for this if we don't mind the function call
     * overhead
     */
   	/*  : 20->25, SNGKS32C->S3C44B0X */
    for (count = 0, isr = 25; count < S3C44B0X_INTNUMLEVELS; count++)
        {
        if (intPendMask & newLevel)
            break;
        isr--;
        intPendMask >>= 1;
        }
    *pVector = isr;

    /* Acknowledge the interrupt as given in SNGKS32C ARM7 sample code */
    /*SNGKS32C_INT_REG_WRITE(SNGKS32C_INTPEND,(1 << isr));*/	/*  : deleted */

    return OK;
    }

/*******************************************************************************
*
* sngks32cIntLvlEnable - enable a single interrupt level
*
* Enable a specific interrupt level.  The enabled level will be allowed to
* generate an interrupt, when the overall interrupt level is set below the
* specified level.  Without being enabled, the interrupt is blocked regardless
* of the overall interrupt level setting.
*
* RETURNS: OK or ERROR if the specified level cannot be enabled.
*/

STATUS  sngks32cIntLvlEnable
    (
    int level  /* level to be enabled */
    )
    {
    int key;

    if (level < 0 ||
        level >= S3C44B0X_INTNUMLEVELS)

        return ERROR;

    /* clear bit in mask register */
    key = intLock ();
    sngks32cIntLvlEnabled |= ((1 << level));
    SNGKS32C_INT_REG_WRITE (S3C44B0X_INTENB, ((~sngks32cIntLvlEnabled) & S3C44B0X_INTMASK_VAL));
    intUnlock (key);

    return OK;
    }

/*******************************************************************************
*
* sngks32cIntLvlDisable - disable a single interrupt level
*
* Disable a specific interrupt level.  The disabled level is prevented
* from generating an interrupt even if the overall interrupt level is set
* below the specified level.
*
* RETURNS: OK or ERROR, if the specified interrupt level cannot be disabled.
*/

STATUS  sngks32cIntLvlDisable
    (
    int level  /* level to be disabled */
    )
    {
    int key;

    if (level < 0 ||
        level >= S3C44B0X_INTNUMLEVELS)
        return ERROR;

    /* set bit in mask register */
    key = intLock ();
    sngks32cIntLvlEnabled &= ~(1 << level);
    SNGKS32C_INT_REG_WRITE (S3C44B0X_INTENB, ((~sngks32cIntLvlEnabled) & S3C44B0X_INTMASK_VAL));
    intUnlock (key);


    return OK;
    }