isa_irqhandler.c revision 1.17 1 /* $NetBSD: isa_irqhandler.c,v 1.17 2007/12/03 15:34:20 ad Exp $ */
2
3 /*
4 * Copyright 1997
5 * Digital Equipment Corporation. All rights reserved.
6 *
7 * This software is furnished under license and may be used and
8 * copied only in accordance with the following terms and conditions.
9 * Subject to these conditions, you may download, copy, install,
10 * use, modify and distribute this software in source and/or binary
11 * form. No title or ownership is transferred hereby.
12 *
13 * 1) Any source code used, modified or distributed must reproduce
14 * and retain this copyright notice and list of conditions as
15 * they appear in the source file.
16 *
17 * 2) No right is granted to use any trade name, trademark, or logo of
18 * Digital Equipment Corporation. Neither the "Digital Equipment
19 * Corporation" name nor any trademark or logo of Digital Equipment
20 * Corporation may be used to endorse or promote products derived
21 * from this software without the prior written permission of
22 * Digital Equipment Corporation.
23 *
24 * 3) This software is provided "AS-IS" and any express or implied
25 * warranties, including but not limited to, any implied warranties
26 * of merchantability, fitness for a particular purpose, or
27 * non-infringement are disclaimed. In no event shall DIGITAL be
28 * liable for any damages whatsoever, and in particular, DIGITAL
29 * shall not be liable for special, indirect, consequential, or
30 * incidental damages or damages for lost profits, loss of
31 * revenue or loss of use, whether such damages arise in contract,
32 * negligence, tort, under statute, in equity, at law or otherwise,
33 * even if advised of the possibility of such damage.
34 */
35
36 /*
37 * Copyright (c) 1994-1998 Mark Brinicombe.
38 * Copyright (c) 1994 Brini.
39 * All rights reserved.
40 *
41 * This code is derived from software written for Brini by Mark Brinicombe
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by Mark Brinicombe
54 * for the NetBSD Project.
55 * 4. The name of the company nor the name of the author may be used to
56 * endorse or promote products derived from this software without specific
57 * prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
60 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
61 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
62 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
63 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
64 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
65 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
66 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
67 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
68 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
69 *
70 * IRQ/FIQ initialisation, claim, release and handler routines
71 *
72 * from: irqhandler.c
73 *
74 * Created : 30/09/94
75 */
76
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: isa_irqhandler.c,v 1.17 2007/12/03 15:34:20 ad Exp $");
79
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/syslog.h>
83 #include <sys/malloc.h>
84
85 #include <uvm/uvm_extern.h>
86
87 #include <machine/intr.h>
88 #include <machine/irqhandler.h>
89 #include <machine/cpu.h>
90
91 irqhandler_t *irqhandlers[NIRQS];
92
93 int current_intr_depth;
94 u_int current_mask;
95 u_int actual_mask;
96 u_int disabled_mask;
97 u_int irqmasks[IPL_LEVELS];
98
99 /* Prototypes */
100
101 extern void set_spl_masks(void);
102 void irq_calculatemasks(void);
103 void stray_irqhandler(u_int);
104
105 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b)
106
107 /*
108 * void irq_init(void)
109 *
110 * Initialise the IRQ/FIQ sub system
111 */
112
113 void
114 irq_init()
115 {
116 int loop;
117
118 /* Clear all the IRQ handlers and the irq block masks */
119 for (loop = 0; loop < NIRQS; ++loop) {
120 irqhandlers[loop] = NULL;
121 }
122
123 /*
124 * Setup the irqmasks for the different Interrupt Priority Levels
125 * We will start with no bits set and these will be updated as handlers
126 * are installed at different IPL's.
127 */
128 for (loop = 0; loop < IPL_LEVELS; ++loop)
129 irqmasks[loop] = 0;
130
131 current_intr_depth = 0;
132 current_mask = 0x00000000;
133 disabled_mask = 0x00000000;
134 actual_mask = 0x00000000;
135
136 set_spl_masks();
137
138 /* Enable IRQ's and FIQ's */
139 enable_interrupts(I32_bit | F32_bit);
140 }
141
142
143 /*
144 * int irq_claim(int irq, irqhandler_t *handler)
145 *
146 * Enable an IRQ and install a handler for it.
147 */
148
149 int
150 irq_claim(irq, handler, group, name)
151 int irq;
152 irqhandler_t *handler;
153 const char *group;
154 const char *name;
155 {
156
157 #ifdef DIAGNOSTIC
158 /* Sanity check */
159 if (handler == NULL)
160 panic("NULL interrupt handler");
161 if (handler->ih_func == NULL)
162 panic("Interrupt handler does not have a function");
163 #endif /* DIAGNOSTIC */
164
165 /*
166 * IRQ_INSTRUCT indicates that we should get the irq number
167 * from the irq structure
168 */
169 if (irq == IRQ_INSTRUCT)
170 irq = handler->ih_num;
171
172 /* Make sure the irq number is valid */
173 if (irq < 0 || irq >= NIRQS)
174 return(-1);
175
176 /* Make sure the level is valid */
177 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
178 return(-1);
179
180 /* Attach evcnt */
181 evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL,
182 group, name);
183
184 /* Attach handler at top of chain */
185 handler->ih_next = irqhandlers[irq];
186 irqhandlers[irq] = handler;
187
188 /*
189 * Reset the flags for this handler.
190 * As the handler is now in the chain mark it as active.
191 */
192 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
193
194 /*
195 * Record the interrupt number for accounting.
196 * Done here as the accounting number may not be the same as the
197 * IRQ number though for the moment they are
198 */
199 handler->ih_num = irq;
200
201 irq_calculatemasks();
202
203 enable_irq(irq);
204 set_spl_masks();
205 return(0);
206 }
207
208
209 /*
210 * int irq_release(int irq, irqhandler_t *handler)
211 *
212 * Disable an IRQ and remove a handler for it.
213 */
214
215 int
216 irq_release(irq, handler)
217 int irq;
218 irqhandler_t *handler;
219 {
220 irqhandler_t *irqhand;
221 irqhandler_t **prehand;
222
223 /*
224 * IRQ_INSTRUCT indicates that we should get the irq number
225 * from the irq structure
226 */
227 if (irq == IRQ_INSTRUCT)
228 irq = handler->ih_num;
229
230 /* Make sure the irq number is valid */
231 if (irq < 0 || irq >= NIRQS)
232 return(-1);
233
234 /* Locate the handler */
235 prehand = &irqhandlers[irq];
236 irqhand = *prehand;
237
238 while (irqhand && handler != irqhand) {
239 prehand = &irqhand->ih_next;
240 irqhand = *prehand;
241 }
242
243 /* Remove the handler if located */
244 if (irqhand)
245 *prehand = irqhand->ih_next;
246 else
247 return(-1);
248
249 /* The handler has been removed from the chain so mark it as inactive */
250 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
251
252 /* Make sure the head of the handler list is active */
253 if (irqhandlers[irq])
254 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
255
256 evcnt_detach(&irqhand->ih_ev);
257
258 irq_calculatemasks();
259
260 /*
261 * Disable the appropriate mask bit if there are no handlers left for
262 * this IRQ.
263 */
264 if (irqhandlers[irq] == NULL)
265 disable_irq(irq);
266
267 set_spl_masks();
268
269 return(0);
270 }
271
272 /* adapted from .../i386/isa/isa_machdep.c */
273 /*
274 * Recalculate the interrupt masks from scratch.
275 * We could code special registry and deregistry versions of this function that
276 * would be faster, but the code would be nastier, and we don't expect this to
277 * happen very much anyway.
278 */
279 void
280 irq_calculatemasks()
281 {
282 int irq, level;
283 irqhandler_t *ptr;
284 int irqlevel[NIRQS];
285
286 /* First, figure out which levels each IRQ uses. */
287 for (irq = 0; irq < NIRQS; irq++) {
288 int levels = 0;
289 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
290 levels |= 1 << ptr->ih_level;
291 irqlevel[irq] = levels;
292 }
293
294 /* Then figure out which IRQs use each level. */
295 for (level = 0; level < IPL_LEVELS; level++) {
296 int irqs = 0;
297 for (irq = 0; irq < NIRQS; irq++)
298 if (irqlevel[irq] & (1 << level))
299 irqs |= 1 << irq;
300 irqmasks[level] = ~irqs;
301 }
302
303 /*
304 * Enforce a hierarchy that gives slow devices a better chance at not
305 * dropping data.
306 */
307 irqmasks[IPL_SOFTCLOCK] &= irqmasks[IPL_NONE];
308 irqmasks[IPL_SOFTBIO] &= irqmasks[IPL_SOFTCLOCK];
309 irqmasks[IPL_SOFTNET] &= irqmasks[IPL_SOFTBIO];
310 irqmasks[IPL_SOFTSERIAL] &= irqmasks[IPL_SOFTNET];
311 irqmasks[IPL_VM] &= irqmasks[IPL_SOFTSERIAL];
312 irqmasks[IPL_CLOCK] &= irqmasks[IPL_VM];
313 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
314 }
315
316
317 void *
318 intr_claim(irq, level, ih_func, ih_arg, group, name)
319 int irq;
320 int level;
321 int (*ih_func)(void *);
322 void *ih_arg;
323 const char *group;
324 const char *name;
325 {
326 irqhandler_t *ih;
327
328 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT | M_ZERO);
329 if (!ih)
330 panic("intr_claim(): Cannot malloc handler memory");
331
332 ih->ih_level = level;
333 ih->ih_func = ih_func;
334 ih->ih_arg = ih_arg;
335 ih->ih_flags = 0;
336
337 if (irq_claim(irq, ih, group, name) != 0)
338 return(NULL);
339
340 return(ih);
341 }
342
343 int
344 intr_release(arg)
345 void *arg;
346 {
347 irqhandler_t *ih = (irqhandler_t *)arg;
348
349 if (irq_release(ih->ih_num, ih) == 0) {
350 free(ih, M_DEVBUF);
351 return(0);
352 }
353 return(1);
354 }
355
356
357 /*
358 * void disable_irq(int irq)
359 *
360 * Disables a specific irq. The irq is removed from the master irq mask
361 */
362
363 void
364 disable_irq(irq)
365 int irq;
366 {
367 u_int oldirqstate;
368
369 oldirqstate = disable_interrupts(I32_bit);
370 current_mask &= ~(1 << irq);
371 irq_setmasks();
372 restore_interrupts(oldirqstate);
373 }
374
375
376 /*
377 * void enable_irq(int irq)
378 *
379 * Enables a specific irq. The irq is added to the master irq mask
380 * This routine should be used with caution. A handler should already
381 * be installed.
382 */
383
384 void
385 enable_irq(irq)
386 int irq;
387 {
388 u_int oldirqstate;
389
390 oldirqstate = disable_interrupts(I32_bit);
391 current_mask |= (1 << irq);
392 irq_setmasks();
393 restore_interrupts(oldirqstate);
394 }
395
396
397 /*
398 * void stray_irqhandler(u_int mask)
399 *
400 * Handler for stray interrupts. This gets called if a handler cannot be
401 * found for an interrupt.
402 */
403
404 void
405 stray_irqhandler(mask)
406 u_int mask;
407 {
408 static u_int stray_irqs = 0;
409
410 if (++stray_irqs <= 8)
411 log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
412 stray_irqs >= 8 ? ": stopped logging" : "");
413 }
414