irq.c

称植到lpc2124上的UCOS2.85版 是本人初学移植和ARM的成果 可能已有人上传类似的了

/*****************************************************************************/
/* irq.c:  Philips LPC214x家族微控制器中断向量的C文件      	            	 */
/* 作者：焦进星                                                              */
/* 时间：2008年月1月22日                                                     */
/* ARM初学                                                                   */
/*****************************************************************************/

#include "target.h"


/*****************************************************************************
** Function name:		Enable_IRQ
**
** Descriptions:		Enable interrupt 
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/
void Enable_IRQ(void)
{
        int temp;
		__asm 
		{
		    MRS temp,CPSR
			BIC temp,temp, #0x80
			MSR CPSR_c,temp
		}
}
/*****************************************************************************
** Function name:		Disable_IRQ
**
** Descriptions:		Disable interrupt 
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/
void Disable_IRQ(void)
{
        int temp;
		__asm 
		{
		    MRS temp,CPSR
			ORR temp,temp, #0x80
			MSR CPSR_c,temp
		}
}

/*****************************************************************************
** Function name:		FIQ_Exception
**
** Descriptions:		Fast interrupt exceptional handler , change it as needed
**
** parameters:			None
** Returned value:		None
**
******************************************************************************/
void  FIQ_Exception(void)
{
    while(1);                   /* 改为你自己的代码 */
}

/******************************************************************************
** Function name:		DefaultVICHandler
**
** Descriptions:		Default VIC interrupt handler.
**				This handler is set to deal with spurious 
**				interrupt.
**				If the IRQ service routine reads the VIC
**				address register, and no IRQ slot responses
**				as described above, this address is returned.
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void DefaultVIC_Exception (void) 
{
    /* if the IRQ is not installed into the VIC, and interrupt occurs, the
    default interrupt VIC address will be used. This could happen in a race 
    condition. For debugging, use this endless loop to trace back. */
    /* For more details, see Philips appnote AN10414 */
    VICVectAddr = 0;		/* Acknowledge Interrupt */ 
    while ( 1 );
}

/******************************************************************************
** Function name:		init_VIC
**
** Descriptions:		Initialize VIC interrupt controller.
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void init_VIC(void) 
{
    DWORD i = 0;
    DWORD *vect_addr, *vect_cntl;
	extern void DefaultVICHandler(void);
   	
    /* initialize VIC*/
    VICIntEnClr = 0xffffffff;
    VICVectAddr = 0;
    VICIntSelect = 0;

    /* set all the vector and vector control register to 0 */
    for ( i = 0; i < VIC_SIZE; i++ )
    {
	      vect_addr = (DWORD *)(VIC_BASE_ADDR + VECT_ADDR_INDEX + i*4);
	      vect_cntl = (DWORD *)(VIC_BASE_ADDR + VECT_CNTL_INDEX + i*4);
	      *vect_addr = 0;	
	      *vect_cntl = 0;
    }

    /* Install the default VIC handler here */
    VICDefVectAddr = (DWORD)DefaultVICHandler;
	   
    return;
}

/******************************************************************************
** Function name:		install_irq
**
** Descriptions:		Install interrupt handler
**				The max VIC size is 16, but, there are 32 interrupt
**				request inputs. Not all of them can be installed into
**				VIC table at the same time.
**				The order of the interrupt request installation is
**				first come first serve.
** parameters:			Interrupt number and interrupt handler address
** Returned value:		true or false, when the table is full, return false
** 
******************************************************************************/
DWORD install_irq( DWORD HandlerNumber, DWORD IntNumber, void *HandlerAddr )
{
    DWORD *vect_addr;
    DWORD *vect_cntl;

    if ( HandlerNumber >= VIC_SIZE )
    {  
	     return( FALSE );		    /* fatal error, can't find empty vector slot */
    }

    VICIntEnClr = 1 << IntNumber;	/* Disable Interrupt */
    
	vect_addr = (DWORD *)(VIC_BASE_ADDR + VECT_ADDR_INDEX + HandlerNumber*4);
    vect_cntl = (DWORD *)(VIC_BASE_ADDR + VECT_CNTL_INDEX + HandlerNumber*4);
    if (*vect_addr == (DWORD)NULL)
	{
	     *vect_addr = (DWORD)HandlerAddr;	/* set interrupt vector */
	     *vect_cntl = (DWORD)(IRQ_SLOT_EN | IntNumber);
	}
	else
	{
		 return( FALSE );		    /* fatal error, can't find empty vector slot */

	}	   
 
    VICIntEnable = 1 << IntNumber;	/* Enable Interrupt */
    return( TRUE );
}

/******************************************************************************
** Function name:		uninstall_irq
**
** Descriptions:		Uninstall interrupt handler
**				Find the interrupt handler installed in the VIC
**				based on the interrupt number, set the location
**				back to NULL to uninstall it.
** parameters:			Interrupt number
** Returned value:		true or false, when the interrupt number is not found, 
**				return false
** 
******************************************************************************/
DWORD uninstall_irq( DWORD IntNumber )
{
    DWORD i;
    DWORD *vect_addr;
    DWORD *vect_cntl;
      
    VICIntEnClr = 1 << IntNumber;	/* Disable Interrupt */
    
    for (i = 0; i < VIC_SIZE; i++)
    {
	     /* find first un-assigned VIC address for the handler */
	     vect_addr = (DWORD *)(VIC_BASE_ADDR + VECT_ADDR_INDEX + i*4);
	     vect_cntl = (DWORD *)(VIC_BASE_ADDR + VECT_CNTL_INDEX + i*4);
	     if ( (*vect_cntl & ~IRQ_SLOT_EN ) == IntNumber )
	    {
	           *vect_addr = (DWORD)NULL;	    /* clear the VIC entry in the VIC table */
	           *vect_cntl &= ~IRQ_SLOT_EN;	    /* disable SLOT_EN bit */	
	           break;
	     }
    }

    if ( i == VIC_SIZE )
    {
	     return( FALSE );		    /* fatal error, can't find interrupt number 
					                   in vector slot */
    }
    VICIntEnable = 1 << IntNumber;	/* Enable Interrupt */
    return( TRUE );
}

/******************************************************************************
**                            End Of File
******************************************************************************/