i8259intr.c

VxWorks实时系统中的中断控制器驱动程序源代码。

	}
    }

/*******************************************************************************
*
* i8259IntEoiSmm - disable Special Mask Mode with EOI signal to the master PIC
*
* This routine is called at the end of the IRQ0 interrupt handler that is 
* PIT(8253) channel 0 system clock interrupt handler in the Special Mask Mode.
*
*/

VOID i8259IntEoiSmm 
    (
    int irqNo		/* IRQ number to send EOI */
    )
    {
    INT32 oldLevel = intLock ();			/* LOCK INTERRUPT */

    sysOutByte (PIC_IMASK (PIC1_BASE_ADR), i8259Mask);	/* restore old mask */
    sysOutByte (PIC_port1 (PIC1_BASE_ADR), 0x08);	/* disable SMM PIC1 */
    sysOutByte (PIC_IACK (PIC1_BASE_ADR), 0x20);	/* NS EOI to PIC1 */

    intUnlock (oldLevel);				/* UNLOCK INTERRUPT */
    }

/*******************************************************************************
*
* i8259IntEoiMaster - send EOI(end of interrupt) signal to the master PIC.
*
* This routine is called at the end of the interrupt handler.
*
*/

VOID i8259IntEoiMaster 
    (
    INT32 irqNo		/* IRQ number to send EOI */
    )
    {
#ifdef	I8259_EOI_OPTIMIZED	/* optimized version */

    WRS_ASM ("			\
	pushfl;			\
	cli;			\
	movl	$0x20, %edx;	\
	movl	$0x20, %eax;	\
	outb	%al, %dx;	\
	popfl;			\
	");

#else				/* portable version */

    INT32 oldLevel = intLock ();	/* LOCK INTERRUPTS */

    sysOutByte (PIC_IACK (PIC1_BASE_ADR), I8259_EOI); /* non-specific EOI */

    intUnlock (oldLevel);		/* UNLOCK INTERRUPTS */

#endif	/* I8259_EOI_OPTIMIZED */
    }

/*******************************************************************************
*
* i8259IntEoiSlave - send EOI(end of interrupt) signal to the slave PIC.
*
* This routine is called at the end of the interrupt handler in the Normal 
* Fully Nested Mode.  This is kept for the backward compatibility.
*
*/

VOID i8259IntEoiSlave
    (
    INT32 irqNo		/* IRQ number to send EOI */
    )
    {
#ifdef	I8259_EOI_OPTIMIZED	/* optimized version */

    WRS_ASM ("			\
	pushfl;			\
	cli;			\
	movl	$0xa0, %edx;	\
	movl	$0x20, %eax;	\
	outb	%al, %dx;	\
	movl	$0x20, %edx;	\
	outb	%al, %dx;	\
	popfl;			\
	");

#else				/* portable version */

    INT32 oldLevel = intLock ();		/* LOCK INTERRUPTS */

    sysOutByte (PIC_IACK (PIC2_BASE_ADR), I8259_EOI); /* non-specific EOI */
    sysOutByte (PIC_IACK (PIC1_BASE_ADR), I8259_EOI); /* non-specific EOI */

    intUnlock (oldLevel);			/* UNLOCK INTERRUPTS */

#endif	/* I8259_EOI_OPTIMIZED */
    }

/*******************************************************************************
*
* i8259IntEoiSlaveNfnm - send EOI(end of interrupt) signal to the slave PIC.
*
* This routine is called at the end of the interrupt handler in the Normal 
* Fully Nested Mode.
*
*/

VOID i8259IntEoiSlaveNfnm
    (
    INT32 irqNo		/* IRQ number to send EOI */
    )
    {
#ifdef	I8259_EOI_OPTIMIZED	/* optimized version */

    WRS_ASM ("			\
	pushfl;			\
	cli;			\
	movl	$0xa0, %edx;	\
	movl	$0x20, %eax;	\
	outb	%al, %dx;	\
	movl	$0x20, %edx;	\
	outb	%al, %dx;	\
	popfl;			\
	");

#else				/* portable version */

    INT32 oldLevel = intLock ();		/* LOCK INTERRUPTS */

    sysOutByte (PIC_IACK (PIC2_BASE_ADR), I8259_EOI); /* non-specific EOI */
    sysOutByte (PIC_IACK (PIC1_BASE_ADR), I8259_EOI); /* non-specific EOI */

    intUnlock (oldLevel);			/* UNLOCK INTERRUPTS */

#endif	/* I8259_EOI_OPTIMIZED */
    }

/*******************************************************************************
*
* i8259IntEoiSlaveSfnm - send EOI(end of interrupt) signal to the slave PIC.
*
* This routine is called at the end of the interrupt handler in the Special 
* Fully Nested Mode.
*
*/

VOID i8259IntEoiSlaveSfnm
    (
    int irqNo		/* IRQ number to send EOI */
    )
    {
    INT8  inserviceReg;
    INT32 oldLevel = intLock ();			/* LOCK INTERRUPT */

    sysOutByte (PIC_IACK (PIC2_BASE_ADR), 0x20);	/* NS EOI to PIC2 */

    sysOutByte (PIC_port1 (PIC2_BASE_ADR), 0x0b);	/* issue OCW3 */
    inserviceReg = sysInByte (PIC_port1 (PIC2_BASE_ADR)); /* read ISR */
    if (inserviceReg == 0) 
        sysOutByte (PIC_IACK (PIC1_BASE_ADR), 0x20);	/* NS EOI to PIC1 */

    intUnlock (oldLevel);				/* UNLOCK INTERRUPT */
    }

/*******************************************************************************
*
* i8259IntDisable - disable a specified PIC interrupt input line
*
* This routine disables a specified PIC interrupt input line.
*
* RETURNS: OK, always.
*
* SEE ALSO: i8259IntEnable()
*
* ARGSUSED0
*/

LOCAL STATUS i8259IntDisable
    (
    INT32 irqNo        /* IRQ number to disable */
    )
    {

    if (irqNo < 8)
	{
	sysOutByte (PIC_IMASK (PIC1_BASE_ADR),
	    sysInByte (PIC_IMASK (PIC1_BASE_ADR)) | (1 << irqNo));
	}
    else
	{
	sysOutByte (PIC_IMASK (PIC2_BASE_ADR),
	    sysInByte (PIC_IMASK (PIC2_BASE_ADR)) | (1 << (irqNo - 8)));
	}

    return (OK);
    }

/*******************************************************************************
*
* i8259IntEnable - enable a specified PIC interrupt input line
*
* This routine enables a specified PIC interrupt input line.
*
* RETURNS: OK, always.
*
* SEE ALSO: i8259IntDisable()
*
* ARGSUSED0
*/

LOCAL STATUS i8259IntEnable
    (
    INT32 irqNo        /* IRQ number to enable */
    )
    {

    if (irqNo < 8)
	{
	sysOutByte (PIC_IMASK (PIC1_BASE_ADR),
	    sysInByte (PIC_IMASK (PIC1_BASE_ADR)) & ~(1 << irqNo));
	}
    else
	{
	sysOutByte (PIC_IMASK (PIC2_BASE_ADR),
	    sysInByte (PIC_IMASK (PIC2_BASE_ADR)) & ~(1 << (irqNo - 8)));
	}

    return (OK);
    }

/*******************************************************************************
*
* i8259IntLock - lock out all PIC interrupts
*
* This routine saves the mask and locks out all PIC interrupts.
* It should be called in the interrupt disable state(IF bit is 0).
*
* SEE ALSO: i8259IntUnlock()
*
* ARGSUSED0
*/

LOCAL VOID i8259IntLock (void)

    {

    i8259IntMask1 = sysInByte (PIC_IMASK (PIC1_BASE_ADR));
    i8259IntMask2 = sysInByte (PIC_IMASK (PIC2_BASE_ADR));
    sysOutByte (PIC_IMASK (PIC1_BASE_ADR), 0xff);
    sysOutByte (PIC_IMASK (PIC2_BASE_ADR), 0xff);
    }

/*******************************************************************************
*
* i8259IntUnlock - unlock the PIC interrupts
*
* This routine restores the mask and unlocks the PIC interrupts
* It should be called in the interrupt disable state(IF bit is 0).
*
* SEE ALSO: i8259IntLock()
*
* ARGSUSED0
*/

LOCAL VOID i8259IntUnlock (void)

    {

    sysOutByte (PIC_IMASK (PIC1_BASE_ADR), i8259IntMask1);
    sysOutByte (PIC_IMASK (PIC2_BASE_ADR), i8259IntMask2);
    }

#if	FALSE
/*
 * There is a function sysIntLevel() which get the interrupt level from the 
 * interrupt stub, so we don't need it anymore.
 */
/*******************************************************************************
*
* i8259IntLevel - Get IRQ number by reading Interrupt Service Register.
*
* This routine is called to get an IRQ number in service.
*
* RETURNS: 0 - 15.
*
* ARGSUSED0
*/

LOCAL INT32 i8259IntLevel (void)

    {
    INT32 inserviceReg;
    INT32 irq;
    INT32 oldLevel;
    INT32 retry;

    oldLevel = intLock ();

    for (retry=0; retry < 1; retry ++)
	{
        sysOutByte (PIC_port1 (PIC1_BASE_ADR), 0x0b);
        inserviceReg = sysInByte (PIC_port1 (PIC1_BASE_ADR));
        for (irq=0; irq < 8; irq++)
	    if ((inserviceReg & 1) && (irq != 2))
	        goto i8259IntLevelExit;
	    else
	        inserviceReg >>= 1;

        sysOutByte (PIC_port1 (PIC2_BASE_ADR), 0x0b);
        inserviceReg = sysInByte (PIC_port1 (PIC2_BASE_ADR));
        for (irq=8; irq < 16; irq++)
	    if (inserviceReg & 1)
	        goto i8259IntLevelExit;
	    else
	        inserviceReg >>= 1;
	}

    i8259IntLevelExit:
    intUnlock (oldLevel);

    return (irq);
    }
#endif	/* FALSE */

#endif	/* SYMMETRIC_IO_MODE */