xref: /openbsd-src/sys/arch/alpha/dev/shared_intr.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /* $OpenBSD: shared_intr.c,v 1.10 2001/06/25 00:43:07 mickey Exp $ */
2 /* $NetBSD: shared_intr.c,v 1.13 2000/03/19 01:46:18 thorpej Exp $ */
3 
4 /*
5  * Copyright (c) 1996 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Authors: Chris G. Demetriou
9  *
10  * Permission to use, copy, modify and distribute this software and
11  * its documentation is hereby granted, provided that both the copyright
12  * notice and this permission notice appear in all copies of the
13  * software, derivative works or modified versions, and any portions
14  * thereof, and that both notices appear in supporting documentation.
15  *
16  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19  *
20  * Carnegie Mellon requests users of this software to return to
21  *
22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23  *  School of Computer Science
24  *  Carnegie Mellon University
25  *  Pittsburgh PA 15213-3890
26  *
27  * any improvements or extensions that they make and grant Carnegie the
28  * rights to redistribute these changes.
29  */
30 
31 /*
32  * Common shared-interrupt-line functionality.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/syslog.h>
40 #include <sys/queue.h>
41 
42 #include <machine/intr.h>
43 
44 static const char *intr_typename __P((int));
45 
46 static const char *
47 intr_typename(type)
48 	int type;
49 {
50 
51 	switch (type) {
52 	case IST_UNUSABLE:
53 		return ("disabled");
54 	case IST_NONE:
55 		return ("none");
56 	case IST_PULSE:
57 		return ("pulsed");
58 	case IST_EDGE:
59 		return ("edge-triggered");
60 	case IST_LEVEL:
61 		return ("level-triggered");
62 	}
63 	panic("intr_typename: unknown type %d", type);
64 }
65 
66 struct alpha_shared_intr *
67 alpha_shared_intr_alloc(n)
68 	unsigned int n;
69 {
70 	struct alpha_shared_intr *intr;
71 	unsigned int i;
72 
73 	intr = malloc(n * sizeof (struct alpha_shared_intr), M_DEVBUF,
74 	    cold ? M_NOWAIT : M_WAITOK);
75 	if (intr == NULL)
76 		panic("alpha_shared_intr_alloc: couldn't malloc intr");
77 
78 	for (i = 0; i < n; i++) {
79 		TAILQ_INIT(&intr[i].intr_q);
80 		intr[i].intr_sharetype = IST_NONE;
81 		intr[i].intr_dfltsharetype = IST_NONE;
82 		intr[i].intr_nstrays = 0;
83 		intr[i].intr_maxstrays = 5;
84 		intr[i].intr_private = NULL;
85 	}
86 
87 	return (intr);
88 }
89 
90 int
91 alpha_shared_intr_dispatch(intr, num)
92 	struct alpha_shared_intr *intr;
93 	unsigned int num;
94 {
95 	struct alpha_shared_intrhand *ih;
96 	int rv, handled;
97 
98 	ih = intr[num].intr_q.tqh_first;
99 	handled = 0;
100 	while (ih != NULL) {
101 
102 		/*
103 		 * The handler returns one of three values:
104 		 *   0:	This interrupt wasn't for me.
105 		 *   1: This interrupt was for me.
106 		 *  -1: This interrupt might have been for me, but I can't say
107 		 *      for sure.
108 		 */
109 		rv = (*ih->ih_fn)(ih->ih_arg);
110 
111 		handled = handled || (rv != 0);
112 		ih = ih->ih_q.tqe_next;
113 	}
114 
115 	return (handled);
116 }
117 
118 void *
119 alpha_shared_intr_establish(intr, num, type, level, fn, arg, basename)
120 	struct alpha_shared_intr *intr;
121 	unsigned int num;
122 	int type, level;
123 	int (*fn) __P((void *));
124 	void *arg;
125 	const char *basename;
126 {
127 	struct alpha_shared_intrhand *ih;
128 
129 	if (intr[num].intr_sharetype == IST_UNUSABLE) {
130 		printf("alpha_shared_intr_establish: %s %d: unusable\n",
131 		    basename, num);
132 		return NULL;
133 	}
134 
135 	/* no point in sleeping unless someone can free memory. */
136 	ih = malloc(sizeof *ih, M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
137 	if (ih == NULL)
138 		panic("alpha_shared_intr_establish: can't malloc intrhand");
139 
140 #ifdef DIAGNOSTIC
141 	if (type == IST_NONE)
142 		panic("alpha_shared_intr_establish: bogus type");
143 #endif
144 
145 	switch (intr[num].intr_sharetype) {
146 	case IST_EDGE:
147 	case IST_LEVEL:
148 		if (type == intr[num].intr_sharetype)
149 			break;
150 	case IST_PULSE:
151 		if (type != IST_NONE) {
152 			if (intr[num].intr_q.tqh_first == NULL) {
153 				printf("alpha_shared_intr_establish: %s %d: warning: using %s on %s\n",
154 				    basename, num, intr_typename(type),
155 				    intr_typename(intr[num].intr_sharetype));
156 				type = intr[num].intr_sharetype;
157 			} else {
158 				panic("alpha_shared_intr_establish: %s %d: can't share %s with %s",
159 				    basename, num, intr_typename(type),
160 				    intr_typename(intr[num].intr_sharetype));
161 			}
162 		}
163 		break;
164 
165 	case IST_NONE:
166 		/* not currently used; safe */
167 		break;
168 	}
169 
170 	ih->ih_intrhead = intr;
171 	ih->ih_fn = fn;
172 	ih->ih_arg = arg;
173 	ih->ih_level = level;
174 	ih->ih_num = num;
175 
176 	intr[num].intr_sharetype = type;
177 	TAILQ_INSERT_TAIL(&intr[num].intr_q, ih, ih_q);
178 
179 	return (ih);
180 }
181 
182 void
183 alpha_shared_intr_disestablish(intr, cookie, basename)
184 	struct alpha_shared_intr *intr;
185 	void *cookie;
186 	const char *basename;
187 {
188 	struct alpha_shared_intrhand *ih = cookie;
189 	unsigned int num = ih->ih_num;
190 
191 	/*
192 	 * Just remove it from the list and free the entry.  We let
193 	 * the caller deal with resetting the share type, if appropriate.
194 	 */
195 	TAILQ_REMOVE(&intr[num].intr_q, ih, ih_q);
196 }
197 
198 int
199 alpha_shared_intr_get_sharetype(intr, num)
200 	struct alpha_shared_intr *intr;
201 	unsigned int num;
202 {
203 
204 	return (intr[num].intr_sharetype);
205 }
206 
207 int
208 alpha_shared_intr_isactive(intr, num)
209 	struct alpha_shared_intr *intr;
210 	unsigned int num;
211 {
212 
213 	return (intr[num].intr_q.tqh_first != NULL);
214 }
215 
216 void
217 alpha_shared_intr_set_dfltsharetype(intr, num, newdfltsharetype)
218 	struct alpha_shared_intr *intr;
219 	unsigned int num;
220 	int newdfltsharetype;
221 {
222 
223 #ifdef DIAGNOSTIC
224 	if (alpha_shared_intr_isactive(intr, num))
225 		panic("alpha_shared_intr_set_dfltsharetype on active intr");
226 #endif
227 
228 	intr[num].intr_dfltsharetype = newdfltsharetype;
229 	intr[num].intr_sharetype = intr[num].intr_dfltsharetype;
230 }
231 
232 void
233 alpha_shared_intr_set_maxstrays(intr, num, newmaxstrays)
234 	struct alpha_shared_intr *intr;
235 	unsigned int num;
236 	int newmaxstrays;
237 {
238 	int s = splhigh();
239 	intr[num].intr_maxstrays = newmaxstrays;
240 	intr[num].intr_nstrays = 0;
241 	splx(s);
242 }
243 
244 void
245 alpha_shared_intr_stray(intr, num, basename)
246 	struct alpha_shared_intr *intr;
247 	unsigned int num;
248 	const char *basename;
249 {
250 
251 	intr[num].intr_nstrays++;
252 
253 	if (intr[num].intr_maxstrays == 0)
254 		return;
255 
256 	if (intr[num].intr_nstrays <= intr[num].intr_maxstrays)
257 		log(LOG_ERR, "stray %s %d%s\n", basename, num,
258 		    intr[num].intr_nstrays >= intr[num].intr_maxstrays ?
259 		      "; stopped logging" : "");
260 }
261 
262 void
263 alpha_shared_intr_set_private(intr, num, v)
264 	struct alpha_shared_intr *intr;
265 	unsigned int num;
266 	void *v;
267 {
268 
269 	intr[num].intr_private = v;
270 }
271 
272 void *
273 alpha_shared_intr_get_private(intr, num)
274 	struct alpha_shared_intr *intr;
275 	unsigned int num;
276 {
277 
278 	return (intr[num].intr_private);
279 }
280