interrupt.h revision 177940 
1/*-
2 * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/sys/interrupt.h 177940 2008-04-05 19:58:30Z jhb $
27 */
28
29#ifndef _SYS_INTERRUPT_H_
30#define _SYS_INTERRUPT_H_
31
32#include <sys/_lock.h>
33#include <sys/_mutex.h>
34
35struct intr_event;
36struct intr_thread;
37struct trapframe;
38
39/*
40 * Describe a hardware interrupt handler.
41 *
42 * Multiple interrupt handlers for a specific event can be chained
43 * together.
44 */
45struct intr_handler {
46	driver_filter_t	*ih_filter;	/* Filter function. */
47	driver_intr_t	*ih_handler;	/* Handler function. */
48	void		*ih_argument;	/* Argument to pass to handler. */
49	int		 ih_flags;
50	const char	*ih_name;	/* Name of handler. */
51	struct intr_event *ih_event;	/* Event we are connected to. */
52	int		 ih_need;	/* Needs service. */
53	TAILQ_ENTRY(intr_handler) ih_next; /* Next handler for this event. */
54	u_char		 ih_pri;	/* Priority of this handler. */
55	struct intr_thread *ih_thread;	/* Ithread for filtered handler. */
56};
57
58/* Interrupt handle flags kept in ih_flags */
59#define	IH_EXCLUSIVE	0x00000002	/* Exclusive interrupt. */
60#define	IH_ENTROPY	0x00000004	/* Device is a good entropy source. */
61#define	IH_DEAD		0x00000008	/* Handler should be removed. */
62#define	IH_MPSAFE	0x80000000	/* Handler does not need Giant. */
63
64/*
65 * Describe an interrupt event.  An event holds a list of handlers.
66 * The 'pre_ithread', 'post_ithread', 'post_filter', and 'assign_cpu'
67 * hooks are used to invoke MD code for certain operations.
68 *
69 * The 'pre_ithread' hook is called when an interrupt thread for
70 * handlers without filters is scheduled.  It is responsible for
71 * ensuring that 1) the system won't be swamped with an interrupt
72 * storm from the associated source while the ithread runs and 2) the
73 * current CPU is able to receive interrupts from other interrupt
74 * sources.  The first is usually accomplished by disabling
75 * level-triggered interrupts until the ithread completes.  The second
76 * is accomplished on some platforms by acknowledging the interrupt
77 * via an EOI.
78 *
79 * The 'post_ithread' hook is invoked when an ithread finishes.  It is
80 * responsible for ensuring that the associated interrupt source will
81 * trigger an interrupt when it is asserted in the future.  Usually
82 * this is implemented by enabling a level-triggered interrupt that
83 * was previously disabled via the 'pre_ithread' hook.
84 *
85 * The 'post_filter' hook is invoked when a filter handles an
86 * interrupt.  It is responsible for ensuring that the current CPU is
87 * able to receive interrupts again.  On some platforms this is done
88 * by acknowledging the interrupts via an EOI.
89 *
90 * The 'assign_cpu' hook is used to bind an interrupt source to a
91 * specific CPU.  If the interrupt cannot be bound, this function may
92 * return an error.
93 */
94struct intr_event {
95	TAILQ_ENTRY(intr_event) ie_list;
96	TAILQ_HEAD(, intr_handler) ie_handlers; /* Interrupt handlers. */
97	char		ie_name[MAXCOMLEN]; /* Individual event name. */
98	char		ie_fullname[MAXCOMLEN];
99	struct mtx	ie_lock;
100	void		*ie_source;	/* Cookie used by MD code. */
101	struct intr_thread *ie_thread;	/* Thread we are connected to. */
102	void		(*ie_pre_ithread)(void *);
103	void		(*ie_post_ithread)(void *);
104	void		(*ie_post_filter)(void *);
105	int		(*ie_assign_cpu)(void *, u_char);
106	int		ie_flags;
107	int		ie_count;	/* Loop counter. */
108	int		ie_warncnt;	/* Rate-check interrupt storm warns. */
109	struct timeval	ie_warntm;
110	u_char		ie_cpu;		/* CPU this event is bound to. */
111};
112
113/* Interrupt event flags kept in ie_flags. */
114#define	IE_SOFT		0x000001	/* Software interrupt. */
115#define	IE_ENTROPY	0x000002	/* Interrupt is an entropy source. */
116#define	IE_ADDING_THREAD 0x000004	/* Currently building an ithread. */
117
118/* Flags to pass to sched_swi. */
119#define	SWI_DELAY	0x2
120
121/*
122 * Software interrupt numbers in priority order.  The priority determines
123 * the priority of the corresponding interrupt thread.
124 */
125#define	SWI_TTY		0
126#define	SWI_NET		1
127#define	SWI_CAMBIO	2
128#define	SWI_VM		3
129#define	SWI_CLOCK	4
130#define	SWI_TQ_FAST	5
131#define	SWI_TQ		6
132#define	SWI_TQ_GIANT	6
133
134extern struct	intr_event *tty_intr_event;
135extern struct	intr_event *clk_intr_event;
136extern void	*softclock_ih;
137extern void	*vm_ih;
138
139/* Counts and names for statistics (defined in MD code). */
140extern u_long 	eintrcnt[];	/* end of intrcnt[] */
141extern char 	eintrnames[];	/* end of intrnames[] */
142extern u_long 	intrcnt[];	/* counts for for each device and stray */
143extern char 	intrnames[];	/* string table containing device names */
144
145#ifdef DDB
146void	db_dump_intr_event(struct intr_event *ie, int handlers);
147#endif
148u_char	intr_priority(enum intr_type flags);
149int	intr_event_add_handler(struct intr_event *ie, const char *name,
150	    driver_filter_t filter, driver_intr_t handler, void *arg,
151	    u_char pri, enum intr_type flags, void **cookiep);
152int	intr_event_bind(struct intr_event *ie, u_char cpu);
153int	intr_event_create(struct intr_event **event, void *source,
154	    int flags, void (*pre_ithread)(void *),
155	    void (*post_ithread)(void *), void (*post_filter)(void *),
156	    int (*assign_cpu)(void *, u_char), const char *fmt, ...)
157	    __printflike(8, 9);
158int	intr_event_destroy(struct intr_event *ie);
159int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
160int	intr_event_remove_handler(void *cookie);
161void	*intr_handler_source(void *cookie);
162int	swi_add(struct intr_event **eventp, const char *name,
163	    driver_intr_t handler, void *arg, int pri, enum intr_type flags,
164	    void **cookiep);
165void	swi_sched(void *cookie, int flags);
166int	swi_remove(void *cookie);
167
168#endif
169