xref: /netbsd-src/sys/arch/shark/isa/isa_irqhandler.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: isa_irqhandler.c,v 1.8 2006/05/11 12:05:37 yamt 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 1.8 2006/05/11 12:05:37 yamt Exp $");
79 
80 #include "opt_irqstats.h"
81 
82 #include <sys/param.h>
83 #include <sys/systm.h>
84 #include <sys/syslog.h>
85 #include <sys/malloc.h>
86 
87 #include <uvm/uvm_extern.h>
88 
89 #include <machine/intr.h>
90 #include <machine/cpu.h>
91 
92 irqhandler_t *irqhandlers[NIRQS];
93 
94 int current_intr_depth;
95 u_int current_mask;
96 u_int actual_mask;
97 u_int disabled_mask;
98 u_int spl_mask;
99 u_int irqmasks[IPL_LEVELS];
100 
101 extern u_int soft_interrupts;	/* Only so we can initialise it */
102 
103 extern char *_intrnames;
104 
105 /* Prototypes */
106 
107 extern void set_spl_masks(void);
108 void irq_calculatemasks(void);
109 void stray_irqhandler(u_int);
110 
111 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b)
112 
113 /*
114  * void irq_init(void)
115  *
116  * Initialise the IRQ/FIQ sub system
117  */
118 
119 void
120 irq_init()
121 {
122 	int loop;
123 
124 	/* Clear all the IRQ handlers and the irq block masks */
125 	for (loop = 0; loop < NIRQS; ++loop) {
126 		irqhandlers[loop] = NULL;
127 	}
128 
129 	/*
130 	 * Setup the irqmasks for the different Interrupt Priority Levels
131 	 * We will start with no bits set and these will be updated as handlers
132 	 * are installed at different IPL's.
133 	 */
134 	for (loop = 0; loop < IPL_LEVELS; ++loop)
135 		irqmasks[loop] = 0;
136 
137 	current_intr_depth = 0;
138 	current_mask = 0x00000000;
139 	disabled_mask = 0x00000000;
140 	actual_mask = 0x00000000;
141 	spl_mask = 0x00000000;
142 	soft_interrupts = 0x00000000;
143 
144 	set_spl_masks();
145 
146 	/* Enable IRQ's and FIQ's */
147 	enable_interrupts(I32_bit | F32_bit);
148 }
149 
150 
151 /*
152  * int irq_claim(int irq, irqhandler_t *handler)
153  *
154  * Enable an IRQ and install a handler for it.
155  */
156 
157 int
158 irq_claim(irq, handler)
159 	int irq;
160 	irqhandler_t *handler;
161 {
162 
163 #ifdef DIAGNOSTIC
164 	/* Sanity check */
165 	if (handler == NULL)
166 		panic("NULL interrupt handler");
167 	if (handler->ih_func == NULL)
168 		panic("Interrupt handler does not have a function");
169 #endif	/* DIAGNOSTIC */
170 
171 	/*
172 	 * IRQ_INSTRUCT indicates that we should get the irq number
173 	 * from the irq structure
174 	 */
175 	if (irq == IRQ_INSTRUCT)
176 		irq = handler->ih_num;
177 
178 	/* Make sure the irq number is valid */
179 	if (irq < 0 || irq >= NIRQS)
180 		return(-1);
181 
182 	/* Make sure the level is valid */
183 	if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
184     	        return(-1);
185 
186 	/* Attach handler at top of chain */
187 	handler->ih_next = irqhandlers[irq];
188 	irqhandlers[irq] = handler;
189 
190 	/*
191 	 * Reset the flags for this handler.
192 	 * As the handler is now in the chain mark it as active.
193 	 */
194 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
195 
196 	/*
197 	 * Record the interrupt number for accounting.
198 	 * Done here as the accounting number may not be the same as the
199 	 * IRQ number though for the moment they are
200 	 */
201 	handler->ih_num = irq;
202 
203 #ifdef IRQSTATS
204 	/* Get the interrupt name from the head of the list */
205 	if (handler->ih_name) {
206 		char *ptr = _intrnames + (irq * 14);
207 		strcpy(ptr, "             ");
208 		strncpy(ptr, handler->ih_name,
209 		    min(strlen(handler->ih_name), 13));
210 	} else {
211 		char *ptr = _intrnames + (irq * 14);
212 		sprintf(ptr, "irq %2d     ", irq);
213 	}
214 #endif	/* IRQSTATS */
215 
216 	irq_calculatemasks();
217 
218 	enable_irq(irq);
219 	set_spl_masks();
220 	return(0);
221 }
222 
223 
224 /*
225  * int irq_release(int irq, irqhandler_t *handler)
226  *
227  * Disable an IRQ and remove a handler for it.
228  */
229 
230 int
231 irq_release(irq, handler)
232 	int irq;
233 	irqhandler_t *handler;
234 {
235 	irqhandler_t *irqhand;
236 	irqhandler_t **prehand;
237 #ifdef IRQSTATS
238 	extern char *_intrnames;
239 #endif
240 
241 	/*
242 	 * IRQ_INSTRUCT indicates that we should get the irq number
243 	 * from the irq structure
244 	 */
245 	if (irq == IRQ_INSTRUCT)
246 		irq = handler->ih_num;
247 
248 	/* Make sure the irq number is valid */
249 	if (irq < 0 || irq >= NIRQS)
250 		return(-1);
251 
252 	/* Locate the handler */
253 	irqhand = irqhandlers[irq];
254 	prehand = &irqhandlers[irq];
255 
256 	while (irqhand && handler != irqhand) {
257 		prehand = &irqhand;
258 		irqhand = irqhand->ih_next;
259 	}
260 
261 	/* Remove the handler if located */
262 	if (irqhand)
263 		*prehand = irqhand->ih_next;
264 	else
265 		return(-1);
266 
267 	/* Now the handler has been removed from the chain mark is as inactive */
268 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
269 
270 	/* Make sure the head of the handler list is active */
271 	if (irqhandlers[irq])
272 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
273 
274 #ifdef IRQSTATS
275 	/* Get the interrupt name from the head of the list */
276 	if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
277 		char *ptr = _intrnames + (irq * 14);
278 		strcpy(ptr, "             ");
279 		strncpy(ptr, irqhandlers[irq]->ih_name,
280 		    min(strlen(irqhandlers[irq]->ih_name), 13));
281 	} else {
282 		char *ptr = _intrnames + (irq * 14);
283 		sprintf(ptr, "irq %2d     ", irq);
284 	}
285 #endif	/* IRQSTATS */
286 
287 	irq_calculatemasks();
288 
289 	/*
290 	 * Disable the appropriate mask bit if there are no handlers left for
291 	 * this IRQ.
292 	 */
293 	if (irqhandlers[irq] == NULL)
294 		disable_irq(irq);
295 
296 	set_spl_masks();
297 
298 	return(0);
299 }
300 
301 /* adapted from .../i386/isa/isa_machdep.c */
302 /*
303  * Recalculate the interrupt masks from scratch.
304  * We could code special registry and deregistry versions of this function that
305  * would be faster, but the code would be nastier, and we don't expect this to
306  * happen very much anyway.
307  */
308 void
309 irq_calculatemasks()
310 {
311 	int          irq, level;
312 	irqhandler_t *ptr;
313 	int          irqlevel[NIRQS];
314 
315 	/* First, figure out which levels each IRQ uses. */
316 	for (irq = 0; irq < NIRQS; irq++) {
317 		int levels = 0;
318 		for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
319 			levels |= 1 << ptr->ih_level;
320 		irqlevel[irq] = levels;
321 	}
322 
323 	/* Then figure out which IRQs use each level. */
324 	for (level = 0; level < IPL_LEVELS; level++) {
325 		int irqs = 0;
326 		for (irq = 0; irq < NIRQS; irq++)
327 			if (irqlevel[irq] & (1 << level))
328 				irqs |= 1 << irq;
329 		irqmasks[level] = ~irqs;
330 	}
331 
332 	/*
333 	 * Enforce a hierarchy that gives slow devices a better chance at not
334 	 * dropping data.
335 	 */
336 	irqmasks[IPL_NET] &= irqmasks[IPL_BIO];
337 	irqmasks[IPL_TTY] &= irqmasks[IPL_NET];
338 
339 	/*
340 	 * There are tty, network and disk drivers that use free() at interrupt
341 	 * time, so imp > (tty | net | bio).
342 	 */
343 	irqmasks[IPL_VM] &= irqmasks[IPL_TTY];
344 
345 	irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM];
346 
347 	/*
348 	 * Since run queues may be manipulated by both the statclock and tty,
349 	 * network, and disk drivers, statclock > (tty | net | bio).
350 	 */
351 	irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO];
352 
353 	/*
354 	 * IPL_HIGH must block everything that can manipulate a run queue.
355 	 */
356 	irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
357 
358 	/*
359 	 * We need serial drivers to run at the absolute highest priority to
360 	 * avoid overruns, so serial > high.
361 	 */
362 	irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH];
363 }
364 
365 
366 void *
367 intr_claim(irq, level, name, ih_func, ih_arg)
368 	int irq;
369 	int level;
370 	const char *name;
371 	int (*ih_func) __P((void *));
372 	void *ih_arg;
373 {
374 	irqhandler_t *ih;
375 
376 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
377 	if (!ih)
378 		panic("intr_claim(): Cannot malloc handler memory");
379 
380 	ih->ih_level = level;
381 	ih->ih_name = name;
382 	ih->ih_func = ih_func;
383 	ih->ih_arg = ih_arg;
384 	ih->ih_flags = 0;
385 
386 	if (irq_claim(irq, ih) != 0)
387 		return(NULL);
388 	return(ih);
389 }
390 
391 int
392 intr_release(arg)
393 	void *arg;
394 {
395 	irqhandler_t *ih = (irqhandler_t *)arg;
396 
397 	if (irq_release(ih->ih_num, ih) == 0) {
398 		free(ih, M_DEVBUF);
399 		return(0);
400 	}
401 	return(1);
402 }
403 
404 
405 /*
406  * void disable_irq(int irq)
407  *
408  * Disables a specific irq. The irq is removed from the master irq mask
409  */
410 
411 void
412 disable_irq(irq)
413 	int irq;
414 {
415 	u_int oldirqstate;
416 
417 	oldirqstate = disable_interrupts(I32_bit);
418 	current_mask &= ~(1 << irq);
419 	irq_setmasks();
420 	restore_interrupts(oldirqstate);
421 }
422 
423 
424 /*
425  * void enable_irq(int irq)
426  *
427  * Enables a specific irq. The irq is added to the master irq mask
428  * This routine should be used with caution. A handler should already
429  * be installed.
430  */
431 
432 void
433 enable_irq(irq)
434 	int irq;
435 {
436 	u_int oldirqstate;
437 
438 	oldirqstate = disable_interrupts(I32_bit);
439 	current_mask |= (1 << irq);
440 	irq_setmasks();
441 	restore_interrupts(oldirqstate);
442 }
443 
444 
445 /*
446  * void stray_irqhandler(u_int mask)
447  *
448  * Handler for stray interrupts. This gets called if a handler cannot be
449  * found for an interrupt.
450  */
451 
452 void
453 stray_irqhandler(mask)
454 	u_int mask;
455 {
456 	static u_int stray_irqs = 0;
457 
458 	if (++stray_irqs <= 8)
459 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
460 		    stray_irqs >= 8 ? ": stopped logging" : "");
461 }
462