xref: /openbsd/sys/arch/amd64/include/i8259.h (revision 891d7ab6)
1 /*	$OpenBSD: i8259.h,v 1.3 2011/03/23 16:54:34 pirofti Exp $	*/
2 /*	$NetBSD: i8259.h,v 1.3 2003/05/04 22:01:56 fvdl Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * William Jolitz.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)icu.h	5.6 (Berkeley) 5/9/91
36  */
37 
38 #ifndef	_MACHINE_I8259_H_
39 #define	_MACHINE_I8259_H_
40 
41 #include <dev/isa/isareg.h>
42 
43 #ifndef	_LOCORE
44 
45 /*
46  * Interrupt "level" mechanism variables, masks, and macros
47  */
48 extern	unsigned i8259_imen;		/* interrupt mask enable */
49 extern unsigned i8259_setmask(unsigned);
50 
51 #define SET_ICUS()	(outb(IO_ICU1 + 1, imen), outb(IO_ICU2 + 1, imen >> 8))
52 
53 extern void i8259_default_setup(void);
54 extern void i8259_reinit(void);
55 
56 #endif /* !_LOCORE */
57 
58 /*
59  * Interrupt enable bits -- in order of priority
60  */
61 #define	IRQ_SLAVE	2
62 
63 /*
64  * Interrupt Control offset into Interrupt descriptor table (IDT)
65  */
66 #define	ICU_OFFSET	32		/* 0-31 are processor exceptions */
67 #define	ICU_LEN		16		/* 32-47 are ISA interrupts */
68 
69 
70 #define ICU_HARDWARE_MASK
71 
72 /*
73  * These macros are fairly self explanatory.  If ICU_SPECIAL_MASK_MODE is
74  * defined, we try to take advantage of the ICU's `special mask mode' by only
75  * EOIing the interrupts on return.  This avoids the requirement of masking and
76  * unmasking.  We can't do this without special mask mode, because the ICU
77  * would also hold interrupts that it thinks are of lower priority.
78  *
79  * Many machines do not support special mask mode, so by default we don't try
80  * to use it.
81  */
82 
83 #define	IRQ_BIT(num)	(1 << ((num) % 8))
84 #define	IRQ_BYTE(num)	((num) >> 3)
85 
86 #define i8259_late_ack(num)
87 
88 #ifdef ICU_SPECIAL_MASK_MODE
89 
90 #define	i8259_asm_ack1(num)
91 #define	i8259_asm_ack2(num) \
92 	movb	$(0x60|IRQ_SLAVE),%al	/* specific EOI for IRQ2 */	;\
93 	outb	%al,$IO_ICU1
94 #define	i8259_asm_mask(num)
95 #define	i8259_asm_unmask(num) \
96 	movb	$(0x60|(num%8)),%al	/* specific EOI */		;\
97 	outb	%al,$ICUADDR
98 
99 #else /* ICU_SPECIAL_MASK_MODE */
100 
101 #ifndef	AUTO_EOI_1
102 #define	i8259_asm_ack1(num) \
103 	movb	$(0x60|(num%8)),%al	/* specific EOI */		;\
104 	outb	%al,$IO_ICU1
105 #else
106 #define	i8259_asm_ack1(num)
107 #endif
108 
109 #ifndef AUTO_EOI_2
110 #define	i8259_asm_ack2(num) \
111 	movb	$(0x60|(num%8)),%al	/* specific EOI */		;\
112 	outb	%al,$IO_ICU2		/* do the second ICU first */	;\
113 	movb	$(0x60|IRQ_SLAVE),%al	/* specific EOI for IRQ2 */	;\
114 	outb	%al,$IO_ICU1
115 #else
116 #define	i8259_asm_ack2(num)
117 #endif
118 
119 #ifdef PIC_MASKDELAY
120 #define MASKDELAY	pushl %eax ; inb $0x84,%al ; popl %eax
121 #else
122 #define MASKDELAY
123 #endif
124 
125 #ifdef ICU_HARDWARE_MASK
126 
127 #define	i8259_asm_mask(num) \
128 	movb	CVAROFF(i8259_imen, IRQ_BYTE(num)),%al			;\
129 	orb	$IRQ_BIT(num),%al					;\
130 	movb	%al,CVAROFF(i8259_imen, IRQ_BYTE(num))			;\
131 	MASKDELAY							;\
132 	outb	%al,$(ICUADDR+1)
133 #define	i8259_asm_unmask(num) \
134 	movb	CVAROFF(i8259_imen, IRQ_BYTE(num)),%al			;\
135 	andb	$~IRQ_BIT(num),%al					;\
136 	movb	%al,CVAROFF(i8259_imen, IRQ_BYTE(num))			;\
137 	MASKDELAY							;\
138 	outb	%al,$(ICUADDR+1)
139 
140 #else /* ICU_HARDWARE_MASK */
141 
142 #define	i8259_asm_mask(num)
143 #define	i8259_asm_unmask(num)
144 
145 #endif /* ICU_HARDWARE_MASK */
146 #endif /* ICU_SPECIAL_MASK_MODE */
147 
148 #endif /* !_MACHINE_I8259_H_ */
149