xref: /freebsd/sys/sys/interrupt.h (revision a9e0f316b3da4144c654cf77542bc5c51632e896)
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 
29 #ifndef _SYS_INTERRUPT_H_
30 #define _SYS_INTERRUPT_H_
31 
32 #include <sys/_lock.h>
33 #include <sys/_mutex.h>
34 #include <sys/ck.h>
35 
36 struct intr_event;
37 struct intr_thread;
38 struct trapframe;
39 
40 /*
41  * Describe a hardware interrupt handler.
42  *
43  * Multiple interrupt handlers for a specific event can be chained
44  * together.
45  */
46 struct intr_handler {
47 	driver_filter_t	*ih_filter;	/* Filter handler function. */
48 	driver_intr_t	*ih_handler;	/* Threaded handler function. */
49 	void		*ih_argument;	/* Argument to pass to handlers. */
50 	int		 ih_flags;
51 	char		 ih_name[MAXCOMLEN + 1]; /* Name of handler. */
52 	struct intr_event *ih_event;	/* Event we are connected to. */
53 	int		 ih_need;	/* Needs service. */
54 	CK_SLIST_ENTRY(intr_handler) ih_next; /* Next handler for this event. */
55 	u_char		 ih_pri;	/* Priority of this handler. */
56 };
57 
58 /* Interrupt handle flags kept in ih_flags */
59 #define	IH_NET		0x00000001	/* Network. */
60 #define	IH_EXCLUSIVE	0x00000002	/* Exclusive interrupt. */
61 #define	IH_ENTROPY	0x00000004	/* Device is a good entropy source. */
62 #define	IH_DEAD		0x00000008	/* Handler should be removed. */
63 #define	IH_SUSP		0x00000010	/* Device is powered down. */
64 #define	IH_CHANGED	0x40000000	/* Handler state is changed. */
65 #define	IH_MPSAFE	0x80000000	/* Handler does not need Giant. */
66 
67 /*
68  * Describe an interrupt event.  An event holds a list of handlers.
69  * The 'pre_ithread', 'post_ithread', 'post_filter', and 'assign_cpu'
70  * hooks are used to invoke MD code for certain operations.
71  *
72  * The 'pre_ithread' hook is called when an interrupt thread for
73  * handlers without filters is scheduled.  It is responsible for
74  * ensuring that 1) the system won't be swamped with an interrupt
75  * storm from the associated source while the ithread runs and 2) the
76  * current CPU is able to receive interrupts from other interrupt
77  * sources.  The first is usually accomplished by disabling
78  * level-triggered interrupts until the ithread completes.  The second
79  * is accomplished on some platforms by acknowledging the interrupt
80  * via an EOI.
81  *
82  * The 'post_ithread' hook is invoked when an ithread finishes.  It is
83  * responsible for ensuring that the associated interrupt source will
84  * trigger an interrupt when it is asserted in the future.  Usually
85  * this is implemented by enabling a level-triggered interrupt that
86  * was previously disabled via the 'pre_ithread' hook.
87  *
88  * The 'post_filter' hook is invoked when a filter handles an
89  * interrupt.  It is responsible for ensuring that the current CPU is
90  * able to receive interrupts again.  On some platforms this is done
91  * by acknowledging the interrupts via an EOI.
92  *
93  * The 'assign_cpu' hook is used to bind an interrupt source to a
94  * specific CPU.  If the interrupt cannot be bound, this function may
95  * return an error.
96  *
97  * Note that device drivers may also use interrupt events to manage
98  * multiplexing interrupt interrupt handler into handlers for child
99  * devices.  In that case, the above hooks are not used.  The device
100  * can create an event for its interrupt resource and register child
101  * event handlers with that event.  It can then use
102  * intr_event_execute_handlers() to execute non-filter handlers.
103  * Currently filter handlers are not supported by this, but that can
104  * be added by splitting out the filter loop from intr_event_handle()
105  * if desired.
106  */
107 struct intr_event {
108 	TAILQ_ENTRY(intr_event) ie_list;
109 	CK_SLIST_HEAD(, intr_handler) ie_handlers; /* Interrupt handlers. */
110 	char		ie_name[MAXCOMLEN + 1]; /* Individual event name. */
111 	char		ie_fullname[MAXCOMLEN + 1];
112 	struct mtx	ie_lock;
113 	void		*ie_source;	/* Cookie used by MD code. */
114 	struct intr_thread *ie_thread;	/* Thread we are connected to. */
115 	void		(*ie_pre_ithread)(void *);
116 	void		(*ie_post_ithread)(void *);
117 	void		(*ie_post_filter)(void *);
118 	int		(*ie_assign_cpu)(void *, int);
119 	int		ie_flags;
120 	int		ie_hflags;	/* Cumulative flags of all handlers. */
121 	int		ie_count;	/* Loop counter. */
122 	int		ie_warncnt;	/* Rate-check interrupt storm warns. */
123 	struct timeval	ie_warntm;
124 	u_int		ie_irq;		/* Physical irq number if !SOFT. */
125 	int		ie_cpu;		/* CPU this event is bound to. */
126 	volatile int	ie_phase;	/* Switched to establish a barrier. */
127 	volatile int	ie_active[2];	/* Filters in ISR context. */
128 };
129 
130 /* Interrupt event flags kept in ie_flags. */
131 #define	IE_SOFT		0x000001	/* Software interrupt. */
132 #define	IE_ADDING_THREAD 0x000004	/* Currently building an ithread. */
133 
134 /* Flags to pass to swi_sched. */
135 #define	SWI_FROMNMI	0x1
136 #define	SWI_DELAY	0x2
137 
138 /*
139  * Software interrupt numbers.  Historically this was used to determine
140  * the relative priority of SWI ithreads.
141  */
142 #define	SWI_TTY		0
143 #define	SWI_NET		1
144 #define	SWI_CAMBIO	2
145 #define	SWI_BUSDMA	3
146 #define	SWI_CLOCK	4
147 #define	SWI_TQ_FAST	5
148 #define	SWI_TQ		6
149 #define	SWI_TQ_GIANT	6
150 
151 /* Maximum number of stray interrupts to log */
152 #define	INTR_STRAY_LOG_MAX	5
153 
154 struct proc;
155 
156 extern struct	intr_event *clk_intr_event;
157 
158 /* Counts and names for statistics (defined in MD code). */
159 extern u_long 	*intrcnt;	/* counts for each device and stray */
160 extern char 	*intrnames;	/* string table containing device names */
161 extern size_t	sintrcnt;	/* size of intrcnt table */
162 extern size_t	sintrnames;	/* size of intrnames table */
163 
164 #ifdef DDB
165 void	db_dump_intr_event(struct intr_event *ie, int handlers);
166 #endif
167 u_char	intr_priority(enum intr_type flags);
168 int	intr_event_add_handler(struct intr_event *ie, const char *name,
169 	    driver_filter_t filter, driver_intr_t handler, void *arg,
170 	    u_char pri, enum intr_type flags, void **cookiep);
171 int	intr_event_bind(struct intr_event *ie, int cpu);
172 int	intr_event_bind_irqonly(struct intr_event *ie, int cpu);
173 int	intr_event_bind_ithread(struct intr_event *ie, int cpu);
174 struct _cpuset;
175 int	intr_event_bind_ithread_cpuset(struct intr_event *ie,
176 	    struct _cpuset *mask);
177 int	intr_event_create(struct intr_event **event, void *source,
178 	    int flags, u_int irq, void (*pre_ithread)(void *),
179 	    void (*post_ithread)(void *), void (*post_filter)(void *),
180 	    int (*assign_cpu)(void *, int), const char *fmt, ...)
181 	    __printflike(9, 10);
182 int	intr_event_describe_handler(struct intr_event *ie, void *cookie,
183 	    const char *descr);
184 int	intr_event_destroy(struct intr_event *ie);
185 int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
186 int	intr_event_remove_handler(void *cookie);
187 int	intr_event_suspend_handler(void *cookie);
188 int	intr_event_resume_handler(void *cookie);
189 int	intr_getaffinity(int irq, int mode, void *mask);
190 void	*intr_handler_source(void *cookie);
191 int	intr_setaffinity(int irq, int mode, const void *mask);
192 void	_intr_drain(int irq);  /* LinuxKPI only. */
193 int	swi_add(struct intr_event **eventp, const char *name,
194 	    driver_intr_t handler, void *arg, int pri, enum intr_type flags,
195 	    void **cookiep);
196 void	swi_sched(void *cookie, int flags);
197 int	swi_remove(void *cookie);
198 
199 #endif
200