ofw_irqhandler.c revision 1.1.2.2 1 /* $NetBSD: ofw_irqhandler.c,v 1.1.2.2 2002/02/28 04:07:41 nathanw Exp $ */
2
3 /*
4 * Copyright (c) 1994-1998 Mark Brinicombe.
5 * Copyright (c) 1994 Brini.
6 * All rights reserved.
7 *
8 * This code is derived from software written for Brini by Mark Brinicombe
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by Mark Brinicombe
21 * for the NetBSD Project.
22 * 4. The name of the company nor the name of the author may be used to
23 * endorse or promote products derived from this software without specific
24 * prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * from: irqhandler.c
38 *
39 * IRQ/FIQ initialisation, claim, release and handler routines
40 *
41 * Created : 30/09/94
42 */
43
44 #include "opt_irqstats.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/syslog.h>
49 #include <sys/malloc.h>
50
51 #include <uvm/uvm_extern.h>
52
53 #include <machine/intr.h>
54 #include <machine/cpu.h>
55
56 irqhandler_t *irqhandlers[NIRQS];
57
58 int current_intr_depth;
59 u_int current_mask;
60 u_int actual_mask;
61 u_int disabled_mask;
62 u_int spl_mask;
63 u_int irqmasks[IPL_LEVELS];
64 u_int irqblock[NIRQS];
65 extern u_int intrcnt[];
66
67 extern u_int soft_interrupts; /* Only so we can initialise it */
68
69 extern char *_intrnames;
70
71 /* Prototypes */
72
73 int podule_irqhandler __P((void));
74 extern void set_spl_masks __P((void));
75
76 /*
77 * void irq_init(void)
78 *
79 * Initialise the IRQ/FIQ sub system
80 */
81
82 void
83 irq_init()
84 {
85 int loop;
86
87 /* Clear all the IRQ handlers and the irq block masks */
88 for (loop = 0; loop < NIRQS; ++loop) {
89 irqhandlers[loop] = NULL;
90 irqblock[loop] = 0;
91 }
92
93 /*
94 * Setup the irqmasks for the different Interrupt Priority Levels
95 * We will start with no bits set and these will be updated as handlers
96 * are installed at different IPL's.
97 */
98 for (loop = 0; loop < IPL_LEVELS; ++loop)
99 irqmasks[loop] = 0;
100
101 current_intr_depth = 0;
102 current_mask = 0x00000000;
103 disabled_mask = 0x00000000;
104 actual_mask = 0x00000000;
105 spl_mask = 0x00000000;
106 soft_interrupts = 0x00000000;
107
108 set_spl_masks();
109
110 /* Enable IRQ's and FIQ's */
111 enable_interrupts(I32_bit | F32_bit);
112 }
113
114
115 /*
116 * int irq_claim(int irq, irqhandler_t *handler)
117 *
118 * Enable an IRQ and install a handler for it.
119 */
120
121 int
122 irq_claim(irq, handler)
123 int irq;
124 irqhandler_t *handler;
125 {
126 int level;
127 int loop;
128
129 #ifdef DIAGNOSTIC
130 /* Sanity check */
131 if (handler == NULL)
132 panic("NULL interrupt handler\n");
133 if (handler->ih_func == NULL)
134 panic("Interrupt handler does not have a function\n");
135 #endif /* DIAGNOSTIC */
136
137 /*
138 * IRQ_INSTRUCT indicates that we should get the irq number
139 * from the irq structure
140 */
141 if (irq == IRQ_INSTRUCT)
142 irq = handler->ih_num;
143
144 /* Make sure the irq number is valid */
145 if (irq < 0 || irq >= NIRQS)
146 return(-1);
147
148 /* Make sure the level is valid */
149 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
150 return(-1);
151
152 /* Attach handler at top of chain */
153 handler->ih_next = irqhandlers[irq];
154 irqhandlers[irq] = handler;
155
156 /*
157 * Reset the flags for this handler.
158 * As the handler is now in the chain mark it as active.
159 */
160 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
161
162 /*
163 * Record the interrupt number for accounting.
164 * Done here as the accounting number may not be the same as the
165 * IRQ number though for the moment they are
166 */
167 handler->ih_num = irq;
168
169 #ifdef IRQSTATS
170 /* Get the interrupt name from the head of the list */
171 if (handler->ih_name) {
172 char *ptr = _intrnames + (irq * 14);
173 strcpy(ptr, " ");
174 strncpy(ptr, handler->ih_name,
175 min(strlen(handler->ih_name), 13));
176 } else {
177 char *ptr = _intrnames + (irq * 14);
178 sprintf(ptr, "irq %2d ", irq);
179 }
180 #endif /* IRQSTATS */
181
182 /*
183 * Update the irq masks.
184 * Find the lowest interrupt priority on the irq chain.
185 * Interrupt is allowable at priorities lower than this.
186 * If ih_level is out of range then don't bother to update
187 * the masks.
188 */
189 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
190 irqhandler_t *ptr;
191
192 /*
193 * Find the lowest interrupt priority on the irq chain.
194 * Interrupt is allowable at priorities lower than this.
195 */
196 ptr = irqhandlers[irq];
197 if (ptr) {
198 level = ptr->ih_level - 1;
199 while (ptr) {
200 if (ptr->ih_level - 1 < level)
201 level = ptr->ih_level - 1;
202 ptr = ptr->ih_next;
203 }
204 while (level >= 0) {
205 irqmasks[level] |= (1 << irq);
206 --level;
207 }
208 }
209
210 #include "sl.h"
211 #include "ppp.h"
212 #if NSL > 0 || NPPP > 0
213 /* In the presence of SLIP or PPP, splimp > spltty. */
214 irqmasks[IPL_NET] &= irqmasks[IPL_TTY];
215 #endif
216 }
217
218 /*
219 * We now need to update the irqblock array. This array indicates
220 * what other interrupts should be blocked when interrupt is asserted
221 * This basically emulates hardware interrupt priorities e.g. by
222 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt
223 * is asserted. For each interrupt we find the highest IPL and set
224 * the block mask to the interrupt mask for that level.
225 */
226
227 for (loop = 0; loop < NIRQS; ++loop) {
228 irqhandler_t *ptr;
229
230 ptr = irqhandlers[loop];
231 if (ptr) {
232 /* There is at least 1 handler so scan the chain */
233 level = ptr->ih_level;
234 while (ptr) {
235 if (ptr->ih_level > level)
236 level = ptr->ih_level;
237 ptr = ptr->ih_next;
238 }
239 irqblock[loop] = ~irqmasks[level];
240 } else
241 /* No handlers for this irq so nothing to block */
242 irqblock[loop] = 0;
243 }
244
245 enable_irq(irq);
246 set_spl_masks();
247
248 return(0);
249 }
250
251
252 /*
253 * int irq_release(int irq, irqhandler_t *handler)
254 *
255 * Disable an IRQ and remove a handler for it.
256 */
257
258 int
259 irq_release(irq, handler)
260 int irq;
261 irqhandler_t *handler;
262 {
263 int level;
264 int loop;
265 irqhandler_t *irqhand;
266 irqhandler_t **prehand;
267 extern char *_intrnames;
268
269 /*
270 * IRQ_INSTRUCT indicates that we should get the irq number
271 * from the irq structure
272 */
273 if (irq == IRQ_INSTRUCT)
274 irq = handler->ih_num;
275
276 /* Make sure the irq number is valid */
277 if (irq < 0 || irq >= NIRQS)
278 return(-1);
279
280 /* Locate the handler */
281 irqhand = irqhandlers[irq];
282 prehand = &irqhandlers[irq];
283
284 while (irqhand && handler != irqhand) {
285 prehand = &irqhand;
286 irqhand = irqhand->ih_next;
287 }
288
289 /* Remove the handler if located */
290 if (irqhand)
291 *prehand = irqhand->ih_next;
292 else
293 return(-1);
294
295 /* Now the handler has been removed from the chain mark is as inactive */
296 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
297
298 /* Make sure the head of the handler list is active */
299 if (irqhandlers[irq])
300 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
301
302 #ifdef IRQSTATS
303 /* Get the interrupt name from the head of the list */
304 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
305 char *ptr = _intrnames + (irq * 14);
306 strcpy(ptr, " ");
307 strncpy(ptr, irqhandlers[irq]->ih_name,
308 min(strlen(irqhandlers[irq]->ih_name), 13));
309 } else {
310 char *ptr = _intrnames + (irq * 14);
311 sprintf(ptr, "irq %2d ", irq);
312 }
313 #endif /* IRQSTATS */
314
315 /*
316 * Update the irq masks.
317 * If ih_level is out of range then don't bother to update
318 * the masks.
319 */
320 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
321 irqhandler_t *ptr;
322
323 /* Clean the bit from all the masks */
324 for (level = 0; level < IPL_LEVELS; ++level)
325 irqmasks[level] &= ~(1 << irq);
326
327 /*
328 * Find the lowest interrupt priority on the irq chain.
329 * Interrupt is allowable at priorities lower than this.
330 */
331 ptr = irqhandlers[irq];
332 if (ptr) {
333 level = ptr->ih_level - 1;
334 while (ptr) {
335 if (ptr->ih_level - 1 < level)
336 level = ptr->ih_level - 1;
337 ptr = ptr->ih_next;
338 }
339 while (level >= 0) {
340 irqmasks[level] |= (1 << irq);
341 --level;
342 }
343 }
344 }
345
346 /*
347 * We now need to update the irqblock array. This array indicates
348 * what other interrupts should be blocked when interrupt is asserted
349 * This basically emulates hardware interrupt priorities e.g. by
350 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt
351 * is asserted. For each interrupt we find the highest IPL and set
352 * the block mask to the interrupt mask for that level.
353 */
354 for (loop = 0; loop < NIRQS; ++loop) {
355 irqhandler_t *ptr;
356
357 ptr = irqhandlers[loop];
358 if (ptr) {
359 /* There is at least 1 handler so scan the chain */
360 level = ptr->ih_level;
361 while (ptr) {
362 if (ptr->ih_level > level)
363 level = ptr->ih_level;
364 ptr = ptr->ih_next;
365 }
366 irqblock[loop] = ~irqmasks[level];
367 } else
368 /* No handlers for this irq so nothing to block */
369 irqblock[loop] = 0;
370 }
371
372 /*
373 * Disable the appropriate mask bit if there are no handlers left for
374 * this IRQ.
375 */
376 if (irqhandlers[irq] == NULL)
377 disable_irq(irq);
378
379 set_spl_masks();
380
381 return(0);
382 }
383
384
385 void *
386 intr_claim(irq, level, name, ih_func, ih_arg)
387 int irq;
388 int level;
389 const char *name;
390 int (*ih_func) __P((void *));
391 void *ih_arg;
392 {
393 irqhandler_t *ih;
394
395 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
396 if (!ih)
397 panic("intr_claim(): Cannot malloc handler memory\n");
398
399 ih->ih_level = level;
400 ih->ih_name = name;
401 ih->ih_func = ih_func;
402 ih->ih_arg = ih_arg;
403 ih->ih_flags = 0;
404
405 if (irq_claim(irq, ih) != 0)
406 return(NULL);
407 return(ih);
408 }
409
410
411 int
412 intr_release(arg)
413 void *arg;
414 {
415 irqhandler_t *ih = (irqhandler_t *)arg;
416
417 if (irq_release(ih->ih_num, ih) == 0) {
418 free(ih, M_DEVBUF);
419 return(0);
420 }
421 return(1);
422 }
423
424
425 /*
426 * void disable_irq(int irq)
427 *
428 * Disables a specific irq. The irq is removed from the master irq mask
429 */
430
431 void
432 disable_irq(irq)
433 int irq;
434 {
435 register int oldirqstate;
436
437 oldirqstate = disable_interrupts(I32_bit);
438 current_mask &= ~(1 << irq);
439 irq_setmasks();
440 restore_interrupts(oldirqstate);
441 }
442
443
444 /*
445 * void enable_irq(int irq)
446 *
447 * Enables a specific irq. The irq is added to the master irq mask
448 * This routine should be used with caution. A handler should already
449 * be installed.
450 */
451
452 void
453 enable_irq(irq)
454 int irq;
455 {
456 register u_int oldirqstate;
457
458 oldirqstate = disable_interrupts(I32_bit);
459 current_mask |= (1 << irq);
460 irq_setmasks();
461 restore_interrupts(oldirqstate);
462 }
463
464
465 /*
466 * void stray_irqhandler(u_int mask)
467 *
468 * Handler for stray interrupts. This gets called if a handler cannot be
469 * found for an interrupt.
470 */
471
472 void
473 stray_irqhandler(mask)
474 u_int mask;
475 {
476 static u_int stray_irqs = 0;
477
478 if (++stray_irqs <= 8)
479 log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
480 stray_irqs >= 8 ? ": stopped logging" : "");
481 }
482