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 * $FreeBSD$
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 handler function. */
47	driver_intr_t	*ih_handler;	/* Threaded handler function. */
48	void		*ih_argument;	/* Argument to pass to handlers. */
49	int		 ih_flags;
50	char		 ih_name[MAXCOMLEN + 1]; /* 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 *
94 * Note that device drivers may also use interrupt events to manage
95 * multiplexing interrupt interrupt handler into handlers for child
96 * devices.  In that case, the above hooks are not used.  The device
97 * can create an event for its interrupt resource and register child
98 * event handlers with that event.  It can then use
99 * intr_event_execute_handlers() to execute non-filter handlers.
100 * Currently filter handlers are not supported by this, but that can
101 * be added by splitting out the filter loop from intr_event_handle()
102 * if desired.
103 */
104struct intr_event {
105	TAILQ_ENTRY(intr_event) ie_list;
106	TAILQ_HEAD(, intr_handler) ie_handlers; /* Interrupt handlers. */
107	char		ie_name[MAXCOMLEN + 1]; /* Individual event name. */
108	char		ie_fullname[MAXCOMLEN + 1];
109	struct mtx	ie_lock;
110	void		*ie_source;	/* Cookie used by MD code. */
111	struct intr_thread *ie_thread;	/* Thread we are connected to. */
112	void		(*ie_pre_ithread)(void *);
113	void		(*ie_post_ithread)(void *);
114	void		(*ie_post_filter)(void *);
115	int		(*ie_assign_cpu)(void *, u_char);
116	int		ie_flags;
117	int		ie_count;	/* Loop counter. */
118	int		ie_warncnt;	/* Rate-check interrupt storm warns. */
119	struct timeval	ie_warntm;
120	int		ie_irq;		/* Physical irq number if !SOFT. */
121	u_char		ie_cpu;		/* CPU this event is bound to. */
122};
123
124/* Interrupt event flags kept in ie_flags. */
125#define	IE_SOFT		0x000001	/* Software interrupt. */
126#define	IE_ENTROPY	0x000002	/* Interrupt is an entropy source. */
127#define	IE_ADDING_THREAD 0x000004	/* Currently building an ithread. */
128
129/* Flags to pass to sched_swi. */
130#define	SWI_DELAY	0x2
131
132/*
133 * Software interrupt numbers in priority order.  The priority determines
134 * the priority of the corresponding interrupt thread.
135 */
136#define	SWI_TTY		0
137#define	SWI_NET		1
138#define	SWI_CAMBIO	2
139#define	SWI_VM		3
140#define	SWI_CLOCK	4
141#define	SWI_TQ_FAST	5
142#define	SWI_TQ		6
143#define	SWI_TQ_GIANT	6
144
145struct proc;
146
147extern struct	intr_event *tty_intr_event;
148extern struct	intr_event *clk_intr_event;
149extern void	*vm_ih;
150
151/* Counts and names for statistics (defined in MD code). */
152extern u_long 	intrcnt[];	/* counts for for each device and stray */
153extern char 	intrnames[];	/* string table containing device names */
154extern size_t	sintrcnt;	/* size of intrcnt table */
155extern size_t	sintrnames;	/* size of intrnames table */
156
157#ifdef DDB
158void	db_dump_intr_event(struct intr_event *ie, int handlers);
159#endif
160u_char	intr_priority(enum intr_type flags);
161int	intr_event_add_handler(struct intr_event *ie, const char *name,
162	    driver_filter_t filter, driver_intr_t handler, void *arg,
163	    u_char pri, enum intr_type flags, void **cookiep);
164int	intr_event_bind(struct intr_event *ie, u_char cpu);
165int	intr_event_create(struct intr_event **event, void *source,
166	    int flags, int irq, void (*pre_ithread)(void *),
167	    void (*post_ithread)(void *), void (*post_filter)(void *),
168	    int (*assign_cpu)(void *, u_char), const char *fmt, ...)
169	    __printflike(9, 10);
170int	intr_event_describe_handler(struct intr_event *ie, void *cookie,
171	    const char *descr);
172int	intr_event_destroy(struct intr_event *ie);
173void	intr_event_execute_handlers(struct proc *p, struct intr_event *ie);
174int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
175int	intr_event_remove_handler(void *cookie);
176int	intr_getaffinity(int irq, void *mask);
177void	*intr_handler_source(void *cookie);
178int	intr_setaffinity(int irq, void *mask);
179void	_intr_drain(int irq);  /* Linux compat only. */
180int	swi_add(struct intr_event **eventp, const char *name,
181	    driver_intr_t handler, void *arg, int pri, enum intr_type flags,
182	    void **cookiep);
183void	swi_sched(void *cookie, int flags);
184int	swi_remove(void *cookie);
185
186#endif
187