xref: /freebsd/sys/sys/interrupt.h (revision b0b1dbdd)
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 
35 struct intr_event;
36 struct intr_thread;
37 struct trapframe;
38 
39 /*
40  * Describe a hardware interrupt handler.
41  *
42  * Multiple interrupt handlers for a specific event can be chained
43  * together.
44  */
45 struct 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  */
104 struct 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 *, int);
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 	int		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 
145 struct proc;
146 
147 extern struct	intr_event *tty_intr_event;
148 extern struct	intr_event *clk_intr_event;
149 extern void	*vm_ih;
150 
151 /* Counts and names for statistics (defined in MD code). */
152 extern u_long 	intrcnt[];	/* counts for for each device and stray */
153 extern char 	intrnames[];	/* string table containing device names */
154 extern size_t	sintrcnt;	/* size of intrcnt table */
155 extern size_t	sintrnames;	/* size of intrnames table */
156 
157 #ifdef DDB
158 void	db_dump_intr_event(struct intr_event *ie, int handlers);
159 #endif
160 u_char	intr_priority(enum intr_type flags);
161 int	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);
164 int	intr_event_bind(struct intr_event *ie, int cpu);
165 int	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 *, int), const char *fmt, ...)
169 	    __printflike(9, 10);
170 int	intr_event_describe_handler(struct intr_event *ie, void *cookie,
171 	    const char *descr);
172 int	intr_event_destroy(struct intr_event *ie);
173 void	intr_event_execute_handlers(struct proc *p, struct intr_event *ie);
174 int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
175 int	intr_event_remove_handler(void *cookie);
176 int	intr_getaffinity(int irq, void *mask);
177 void	*intr_handler_source(void *cookie);
178 int	intr_setaffinity(int irq, void *mask);
179 void	_intr_drain(int irq);  /* Linux compat only. */
180 int	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);
183 void	swi_sched(void *cookie, int flags);
184 int	swi_remove(void *cookie);
185 
186 #endif
187