xref: /freebsd/sys/sys/interrupt.h (revision 4e8d558c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #ifndef _SYS_INTERRUPT_H_
32 #define _SYS_INTERRUPT_H_
33 
34 #include <sys/_lock.h>
35 #include <sys/_mutex.h>
36 #include <sys/ck.h>
37 
38 struct intr_event;
39 struct intr_thread;
40 struct trapframe;
41 
42 /*
43  * Describe a hardware interrupt handler.
44  *
45  * Multiple interrupt handlers for a specific event can be chained
46  * together.
47  */
48 struct intr_handler {
49 	driver_filter_t	*ih_filter;	/* Filter handler function. */
50 	driver_intr_t	*ih_handler;	/* Threaded handler function. */
51 	void		*ih_argument;	/* Argument to pass to handlers. */
52 	int		 ih_flags;
53 	char		 ih_name[MAXCOMLEN + 1]; /* Name of handler. */
54 	struct intr_event *ih_event;	/* Event we are connected to. */
55 	int		 ih_need;	/* Needs service. */
56 	CK_SLIST_ENTRY(intr_handler) ih_next; /* Next handler for this event. */
57 	u_char		 ih_pri;	/* Priority of this handler. */
58 };
59 
60 /* Interrupt handle flags kept in ih_flags */
61 #define	IH_NET		0x00000001	/* Network. */
62 #define	IH_EXCLUSIVE	0x00000002	/* Exclusive interrupt. */
63 #define	IH_ENTROPY	0x00000004	/* Device is a good entropy source. */
64 #define	IH_DEAD		0x00000008	/* Handler should be removed. */
65 #define	IH_SUSP		0x00000010	/* Device is powered down. */
66 #define	IH_CHANGED	0x40000000	/* Handler state is changed. */
67 #define	IH_MPSAFE	0x80000000	/* Handler does not need Giant. */
68 
69 /*
70  * Describe an interrupt event.  An event holds a list of handlers.
71  * The 'pre_ithread', 'post_ithread', 'post_filter', and 'assign_cpu'
72  * hooks are used to invoke MD code for certain operations.
73  *
74  * The 'pre_ithread' hook is called when an interrupt thread for
75  * handlers without filters is scheduled.  It is responsible for
76  * ensuring that 1) the system won't be swamped with an interrupt
77  * storm from the associated source while the ithread runs and 2) the
78  * current CPU is able to receive interrupts from other interrupt
79  * sources.  The first is usually accomplished by disabling
80  * level-triggered interrupts until the ithread completes.  The second
81  * is accomplished on some platforms by acknowledging the interrupt
82  * via an EOI.
83  *
84  * The 'post_ithread' hook is invoked when an ithread finishes.  It is
85  * responsible for ensuring that the associated interrupt source will
86  * trigger an interrupt when it is asserted in the future.  Usually
87  * this is implemented by enabling a level-triggered interrupt that
88  * was previously disabled via the 'pre_ithread' hook.
89  *
90  * The 'post_filter' hook is invoked when a filter handles an
91  * interrupt.  It is responsible for ensuring that the current CPU is
92  * able to receive interrupts again.  On some platforms this is done
93  * by acknowledging the interrupts via an EOI.
94  *
95  * The 'assign_cpu' hook is used to bind an interrupt source to a
96  * specific CPU.  If the interrupt cannot be bound, this function may
97  * return an error.
98  *
99  * Note that device drivers may also use interrupt events to manage
100  * multiplexing interrupt interrupt handler into handlers for child
101  * devices.  In that case, the above hooks are not used.  The device
102  * can create an event for its interrupt resource and register child
103  * event handlers with that event.  It can then use
104  * intr_event_execute_handlers() to execute non-filter handlers.
105  * Currently filter handlers are not supported by this, but that can
106  * be added by splitting out the filter loop from intr_event_handle()
107  * if desired.
108  */
109 struct intr_event {
110 	TAILQ_ENTRY(intr_event) ie_list;
111 	CK_SLIST_HEAD(, intr_handler) ie_handlers; /* Interrupt handlers. */
112 	char		ie_name[MAXCOMLEN + 1]; /* Individual event name. */
113 	char		ie_fullname[MAXCOMLEN + 1];
114 	struct mtx	ie_lock;
115 	void		*ie_source;	/* Cookie used by MD code. */
116 	struct intr_thread *ie_thread;	/* Thread we are connected to. */
117 	void		(*ie_pre_ithread)(void *);
118 	void		(*ie_post_ithread)(void *);
119 	void		(*ie_post_filter)(void *);
120 	int		(*ie_assign_cpu)(void *, int);
121 	int		ie_flags;
122 	int		ie_hflags;	/* Cumulative flags of all handlers. */
123 	int		ie_count;	/* Loop counter. */
124 	int		ie_warncnt;	/* Rate-check interrupt storm warns. */
125 	struct timeval	ie_warntm;
126 	int		ie_irq;		/* Physical irq number if !SOFT. */
127 	int		ie_cpu;		/* CPU this event is bound to. */
128 	volatile int	ie_phase;	/* Switched to establish a barrier. */
129 	volatile int	ie_active[2];	/* Filters in ISR context. */
130 };
131 
132 /* Interrupt event flags kept in ie_flags. */
133 #define	IE_SOFT		0x000001	/* Software interrupt. */
134 #define	IE_ADDING_THREAD 0x000004	/* Currently building an ithread. */
135 
136 /* Flags to pass to swi_sched. */
137 #define	SWI_FROMNMI	0x1
138 #define	SWI_DELAY	0x2
139 
140 /*
141  * Software interrupt numbers.  Historically this was used to determine
142  * the relative priority of SWI ithreads.
143  */
144 #define	SWI_TTY		0
145 #define	SWI_NET		1
146 #define	SWI_CAMBIO	2
147 #define	SWI_BUSDMA	3
148 #define	SWI_CLOCK	4
149 #define	SWI_TQ_FAST	5
150 #define	SWI_TQ		6
151 #define	SWI_TQ_GIANT	6
152 
153 struct proc;
154 
155 extern struct	intr_event *clk_intr_event;
156 
157 /* Counts and names for statistics (defined in MD code). */
158 extern u_long 	*intrcnt;	/* counts for each device and stray */
159 extern char 	*intrnames;	/* string table containing device names */
160 extern size_t	sintrcnt;	/* size of intrcnt table */
161 extern size_t	sintrnames;	/* size of intrnames table */
162 
163 #ifdef DDB
164 void	db_dump_intr_event(struct intr_event *ie, int handlers);
165 #endif
166 u_char	intr_priority(enum intr_type flags);
167 int	intr_event_add_handler(struct intr_event *ie, const char *name,
168 	    driver_filter_t filter, driver_intr_t handler, void *arg,
169 	    u_char pri, enum intr_type flags, void **cookiep);
170 int	intr_event_bind(struct intr_event *ie, int cpu);
171 int	intr_event_bind_irqonly(struct intr_event *ie, int cpu);
172 int	intr_event_bind_ithread(struct intr_event *ie, int cpu);
173 struct _cpuset;
174 int	intr_event_bind_ithread_cpuset(struct intr_event *ie,
175 	    struct _cpuset *mask);
176 int	intr_event_create(struct intr_event **event, void *source,
177 	    int flags, int irq, void (*pre_ithread)(void *),
178 	    void (*post_ithread)(void *), void (*post_filter)(void *),
179 	    int (*assign_cpu)(void *, int), const char *fmt, ...)
180 	    __printflike(9, 10);
181 int	intr_event_describe_handler(struct intr_event *ie, void *cookie,
182 	    const char *descr);
183 int	intr_event_destroy(struct intr_event *ie);
184 int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
185 int	intr_event_remove_handler(void *cookie);
186 int	intr_event_suspend_handler(void *cookie);
187 int	intr_event_resume_handler(void *cookie);
188 int	intr_getaffinity(int irq, int mode, void *mask);
189 void	*intr_handler_source(void *cookie);
190 int	intr_setaffinity(int irq, int mode, void *mask);
191 void	_intr_drain(int irq);  /* LinuxKPI only. */
192 int	swi_add(struct intr_event **eventp, const char *name,
193 	    driver_intr_t handler, void *arg, int pri, enum intr_type flags,
194 	    void **cookiep);
195 void	swi_sched(void *cookie, int flags);
196 int	swi_remove(void *cookie);
197 
198 #endif
199