xref: /netbsd-src/sys/arch/alpha/common/shared_intr.c (revision 89c5a767f8fc7a4633b2d409966e2becbb98ff92)
1 /* $NetBSD: shared_intr.c,v 1.12 2000/02/10 07:45:02 mjacob Exp $ */
2 
3 /*
4  * Copyright (c) 1996 Carnegie-Mellon University.
5  * All rights reserved.
6  *
7  * Authors: Chris G. Demetriou
8  *
9  * Permission to use, copy, modify and distribute this software and
10  * its documentation is hereby granted, provided that both the copyright
11  * notice and this permission notice appear in all copies of the
12  * software, derivative works or modified versions, and any portions
13  * thereof, and that both notices appear in supporting documentation.
14  *
15  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
17  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18  *
19  * Carnegie Mellon requests users of this software to return to
20  *
21  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22  *  School of Computer Science
23  *  Carnegie Mellon University
24  *  Pittsburgh PA 15213-3890
25  *
26  * any improvements or extensions that they make and grant Carnegie the
27  * rights to redistribute these changes.
28  */
29 
30 /*
31  * Common shared-interrupt-line functionality.
32  */
33 
34 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
35 
36 __KERNEL_RCSID(0, "$NetBSD: shared_intr.c,v 1.12 2000/02/10 07:45:02 mjacob Exp $");
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/malloc.h>
42 #include <sys/syslog.h>
43 #include <sys/queue.h>
44 
45 #include <machine/intr.h>
46 
47 static const char *intr_typename __P((int));
48 
49 static const char *
50 intr_typename(type)
51 	int type;
52 {
53 
54 	switch (type) {
55 	case IST_UNUSABLE:
56 		return ("disabled");
57 	case IST_NONE:
58 		return ("none");
59 	case IST_PULSE:
60 		return ("pulsed");
61 	case IST_EDGE:
62 		return ("edge-triggered");
63 	case IST_LEVEL:
64 		return ("level-triggered");
65 	}
66 	panic("intr_typename: unknown type %d", type);
67 }
68 
69 struct alpha_shared_intr *
70 alpha_shared_intr_alloc(n)
71 	unsigned int n;
72 {
73 	struct alpha_shared_intr *intr;
74 	unsigned int i;
75 
76 	intr = malloc(n * sizeof (struct alpha_shared_intr), M_DEVBUF,
77 	    cold ? M_NOWAIT : M_WAITOK);
78 	if (intr == NULL)
79 		panic("alpha_shared_intr_alloc: couldn't malloc intr");
80 
81 	for (i = 0; i < n; i++) {
82 		TAILQ_INIT(&intr[i].intr_q);
83 		intr[i].intr_sharetype = IST_NONE;
84 		intr[i].intr_dfltsharetype = IST_NONE;
85 		intr[i].intr_nstrays = 0;
86 		intr[i].intr_maxstrays = 5;
87 		intr[i].intr_private = NULL;
88 	}
89 
90 	return (intr);
91 }
92 
93 int
94 alpha_shared_intr_dispatch(intr, num)
95 	struct alpha_shared_intr *intr;
96 	unsigned int num;
97 {
98 	struct alpha_shared_intrhand *ih;
99 	int rv, handled;
100 
101 	ih = intr[num].intr_q.tqh_first;
102 	handled = 0;
103 	while (ih != NULL) {
104 
105 		/*
106 		 * The handler returns one of three values:
107 		 *   0:	This interrupt wasn't for me.
108 		 *   1: This interrupt was for me.
109 		 *  -1: This interrupt might have been for me, but I can't say
110 		 *      for sure.
111 		 */
112 		rv = (*ih->ih_fn)(ih->ih_arg);
113 
114 		handled = handled || (rv != 0);
115 		ih = ih->ih_q.tqe_next;
116 	}
117 
118 	return (handled);
119 }
120 
121 void *
122 alpha_shared_intr_establish(intr, num, type, level, fn, arg, basename)
123 	struct alpha_shared_intr *intr;
124 	unsigned int num;
125 	int type, level;
126 	int (*fn) __P((void *));
127 	void *arg;
128 	const char *basename;
129 {
130 	struct alpha_shared_intrhand *ih;
131 
132 	if (intr[num].intr_sharetype == IST_UNUSABLE) {
133 		printf("alpha_shared_intr_establish: %s %d: unusable\n",
134 		    basename, num);
135 		return NULL;
136 	}
137 
138 	/* no point in sleeping unless someone can free memory. */
139 	ih = malloc(sizeof *ih, M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
140 	if (ih == NULL)
141 		panic("alpha_shared_intr_establish: can't malloc intrhand");
142 
143 #ifdef DIAGNOSTIC
144 	if (type == IST_NONE)
145 		panic("alpha_shared_intr_establish: bogus type");
146 #endif
147 
148 	switch (intr[num].intr_sharetype) {
149 	case IST_EDGE:
150 	case IST_LEVEL:
151 		if (type == intr[num].intr_sharetype)
152 			break;
153 	case IST_PULSE:
154 		if (type != IST_NONE) {
155 			if (intr[num].intr_q.tqh_first == NULL) {
156 				printf("alpha_shared_intr_establish: %s %d: warning: using %s on %s\n",
157 				    basename, num, intr_typename(type),
158 				    intr_typename(intr[num].intr_sharetype));
159 				type = intr[num].intr_sharetype;
160 			} else {
161 				panic("alpha_shared_intr_establish: %s %d: can't share %s with %s",
162 				    basename, num, intr_typename(type),
163 				    intr_typename(intr[num].intr_sharetype));
164 			}
165 		}
166 		break;
167 
168 	case IST_NONE:
169 		/* not currently used; safe */
170 		break;
171 	}
172 
173 	ih->ih_fn = fn;
174 	ih->ih_arg = arg;
175 	ih->ih_level = level;
176 	ih->ih_num = num;
177 
178 	intr[num].intr_sharetype = type;
179 	TAILQ_INSERT_TAIL(&intr[num].intr_q, ih, ih_q);
180 
181 	return (ih);
182 }
183 
184 void
185 alpha_shared_intr_disestablish(intr, cookie, basename)
186 	struct alpha_shared_intr *intr;
187 	void *cookie;
188 	const char *basename;
189 {
190 	struct alpha_shared_intrhand *ih = cookie;
191 	unsigned int num = ih->ih_num;
192 
193 	/*
194 	 * Just remove it from the list and free the entry.  We let
195 	 * the caller deal with resetting the share type, if appropriate.
196 	 */
197 	TAILQ_REMOVE(&intr[num].intr_q, ih, ih_q);
198 }
199 
200 int
201 alpha_shared_intr_get_sharetype(intr, num)
202 	struct alpha_shared_intr *intr;
203 	unsigned int num;
204 {
205 
206 	return (intr[num].intr_sharetype);
207 }
208 
209 int
210 alpha_shared_intr_isactive(intr, num)
211 	struct alpha_shared_intr *intr;
212 	unsigned int num;
213 {
214 
215 	return (intr[num].intr_q.tqh_first != NULL);
216 }
217 
218 void
219 alpha_shared_intr_set_dfltsharetype(intr, num, newdfltsharetype)
220 	struct alpha_shared_intr *intr;
221 	unsigned int num;
222 	int newdfltsharetype;
223 {
224 
225 #ifdef DIAGNOSTIC
226 	if (alpha_shared_intr_isactive(intr, num))
227 		panic("alpha_shared_intr_set_dfltsharetype on active intr");
228 #endif
229 
230 	intr[num].intr_dfltsharetype = newdfltsharetype;
231 	intr[num].intr_sharetype = intr[num].intr_dfltsharetype;
232 }
233 
234 void
235 alpha_shared_intr_set_maxstrays(intr, num, newmaxstrays)
236 	struct alpha_shared_intr *intr;
237 	unsigned int num;
238 	int newmaxstrays;
239 {
240 	int s = splhigh();
241 	intr[num].intr_maxstrays = newmaxstrays;
242 	intr[num].intr_nstrays = 0;
243 	splx(s);
244 }
245 
246 void
247 alpha_shared_intr_stray(intr, num, basename)
248 	struct alpha_shared_intr *intr;
249 	unsigned int num;
250 	const char *basename;
251 {
252 
253 	intr[num].intr_nstrays++;
254 
255 	if (intr[num].intr_maxstrays == 0)
256 		return;
257 
258 	if (intr[num].intr_nstrays <= intr[num].intr_maxstrays)
259 		log(LOG_ERR, "stray %s %d%s\n", basename, num,
260 		    intr[num].intr_nstrays >= intr[num].intr_maxstrays ?
261 		      "; stopped logging" : "");
262 }
263 
264 void
265 alpha_shared_intr_set_private(intr, num, v)
266 	struct alpha_shared_intr *intr;
267 	unsigned int num;
268 	void *v;
269 {
270 
271 	intr[num].intr_private = v;
272 }
273 
274 void *
275 alpha_shared_intr_get_private(intr, num)
276 	struct alpha_shared_intr *intr;
277 	unsigned int num;
278 {
279 
280 	return (intr[num].intr_private);
281 }
282