/*      $NetBSD: i8259.h,v 1.4 2003/08/07 16:30:32 agc Exp $    */

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*      @(#)icu.h       5.6 (Berkeley) 5/9/91
*/

#ifndef _X86_I8259_H_
#define _X86_I8259_H_

#include <dev/isa/isareg.h>

#ifndef _LOCORE

/*
* Interrupt "level" mechanism variables, masks, and macros
*/
extern  unsigned i8259_imen;            /* interrupt mask enable */
extern unsigned i8259_setmask(unsigned);

#define SET_ICUS()      (outb(IO_ICU1 + 1, imen), outb(IO_ICU2 + 1, imen >> 8))

extern void i8259_default_setup(void);
extern void i8259_reinit(void);

#endif /* !_LOCORE */

/*
* Interrupt enable bits -- in order of priority
*/
#define IRQ_SLAVE       2

/*
* Interrupt Control offset into Interrupt descriptor table (IDT)
*/
#define ICU_OFFSET      32              /* 0-31 are processor exceptions */
#define ICU_LEN         16              /* 32-47 are ISA interrupts */


#define ICU_HARDWARE_MASK

/*
* These macros are fairly self explanatory.  If ICU_SPECIAL_MASK_MODE is
* defined, we try to take advantage of the ICU's `special mask mode' by only
* EOIing the interrupts on return.  This avoids the requirement of masking and
* unmasking.  We can't do this without special mask mode, because the ICU
* would also hold interrupts that it thinks are of lower priority.
*
* Many machines do not support special mask mode, so by default we don't try
* to use it.
*/

#define IRQ_BIT(num)    (1 << ((num) % 8))
#define IRQ_BYTE(num)   ((num) >> 3)

#define i8259_late_ack(num)

#ifdef ICU_SPECIAL_MASK_MODE

#define i8259_asm_ack1(num)
#define i8259_asm_ack2(num) \
       movb    $(0x60|IRQ_SLAVE),%al   /* specific EOI for IRQ2 */     ;\
       outb    %al,$IO_ICU1
#define i8259_asm_mask(num)
#define i8259_asm_unmask(num) \
       movb    $(0x60|(num%8)),%al     /* specific EOI */              ;\
       outb    %al,$ICUADDR

#else /* ICU_SPECIAL_MASK_MODE */

#ifndef AUTO_EOI_1
#define i8259_asm_ack1(num) \
       movb    $(0x60|(num%8)),%al     /* specific EOI */              ;\
       outb    %al,$IO_ICU1
#else
#define i8259_asm_ack1(num)
#endif

#ifndef AUTO_EOI_2
#define i8259_asm_ack2(num) \
       movb    $(0x60|(num%8)),%al     /* specific EOI */              ;\
       outb    %al,$IO_ICU2            /* do the second ICU first */   ;\
       movb    $(0x60|IRQ_SLAVE),%al   /* specific EOI for IRQ2 */     ;\
       outb    %al,$IO_ICU1
#else
#define i8259_asm_ack2(num)
#endif

#ifdef PIC_MASKDELAY
#define MASKDELAY       pushl %eax ; inb $0x84,%al ; popl %eax
#else
#define MASKDELAY
#endif

#ifdef ICU_HARDWARE_MASK

#define i8259_asm_mask(num) \
       movb    CVAROFF(i8259_imen, IRQ_BYTE(num)),%al                  ;\
       orb     $IRQ_BIT(num),%al                                       ;\
       movb    %al,CVAROFF(i8259_imen, IRQ_BYTE(num))                  ;\
       MASKDELAY                                                       ;\
       outb    %al,$(ICUADDR+1)
#define i8259_asm_unmask(num) \
       movb    CVAROFF(i8259_imen, IRQ_BYTE(num)),%al                  ;\
       andb    $~IRQ_BIT(num),%al                                      ;\
       movb    %al,CVAROFF(i8259_imen, IRQ_BYTE(num))                  ;\
       MASKDELAY                                                       ;\
       outb    %al,$(ICUADDR+1)

#else /* ICU_HARDWARE_MASK */

#define i8259_asm_mask(num)
#define i8259_asm_unmask(num)

#endif /* ICU_HARDWARE_MASK */
#endif /* ICU_SPECIAL_MASK_MODE */

#endif /* !_X86_I8259_H_ */