xref: /netbsd-src/sys/arch/shark/isa/isa_irqhandler.c (revision 37f70797517809cc10ea5abaf7b9568b03746d97)
1 /*	$NetBSD: isa_irqhandler.c,v 1.9 2007/02/18 07:20:40 matt 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 1.9 2007/02/18 07:20:40 matt 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 	softintr_init();
144 
145 	set_spl_masks();
146 
147 	/* Enable IRQ's and FIQ's */
148 	enable_interrupts(I32_bit | F32_bit);
149 }
150 
151 
152 /*
153  * int irq_claim(int irq, irqhandler_t *handler)
154  *
155  * Enable an IRQ and install a handler for it.
156  */
157 
158 int
159 irq_claim(irq, handler)
160 	int irq;
161 	irqhandler_t *handler;
162 {
163 
164 #ifdef DIAGNOSTIC
165 	/* Sanity check */
166 	if (handler == NULL)
167 		panic("NULL interrupt handler");
168 	if (handler->ih_func == NULL)
169 		panic("Interrupt handler does not have a function");
170 #endif	/* DIAGNOSTIC */
171 
172 	/*
173 	 * IRQ_INSTRUCT indicates that we should get the irq number
174 	 * from the irq structure
175 	 */
176 	if (irq == IRQ_INSTRUCT)
177 		irq = handler->ih_num;
178 
179 	/* Make sure the irq number is valid */
180 	if (irq < 0 || irq >= NIRQS)
181 		return(-1);
182 
183 	/* Make sure the level is valid */
184 	if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
185     	        return(-1);
186 
187 	/* Attach handler at top of chain */
188 	handler->ih_next = irqhandlers[irq];
189 	irqhandlers[irq] = handler;
190 
191 	/*
192 	 * Reset the flags for this handler.
193 	 * As the handler is now in the chain mark it as active.
194 	 */
195 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
196 
197 	/*
198 	 * Record the interrupt number for accounting.
199 	 * Done here as the accounting number may not be the same as the
200 	 * IRQ number though for the moment they are
201 	 */
202 	handler->ih_num = irq;
203 
204 #ifdef IRQSTATS
205 	/* Get the interrupt name from the head of the list */
206 	if (handler->ih_name) {
207 		char *ptr = _intrnames + (irq * 14);
208 		strcpy(ptr, "             ");
209 		strncpy(ptr, handler->ih_name,
210 		    min(strlen(handler->ih_name), 13));
211 	} else {
212 		char *ptr = _intrnames + (irq * 14);
213 		sprintf(ptr, "irq %2d     ", irq);
214 	}
215 #endif	/* IRQSTATS */
216 
217 	irq_calculatemasks();
218 
219 	enable_irq(irq);
220 	set_spl_masks();
221 	return(0);
222 }
223 
224 
225 /*
226  * int irq_release(int irq, irqhandler_t *handler)
227  *
228  * Disable an IRQ and remove a handler for it.
229  */
230 
231 int
232 irq_release(irq, handler)
233 	int irq;
234 	irqhandler_t *handler;
235 {
236 	irqhandler_t *irqhand;
237 	irqhandler_t **prehand;
238 #ifdef IRQSTATS
239 	extern char *_intrnames;
240 #endif
241 
242 	/*
243 	 * IRQ_INSTRUCT indicates that we should get the irq number
244 	 * from the irq structure
245 	 */
246 	if (irq == IRQ_INSTRUCT)
247 		irq = handler->ih_num;
248 
249 	/* Make sure the irq number is valid */
250 	if (irq < 0 || irq >= NIRQS)
251 		return(-1);
252 
253 	/* Locate the handler */
254 	irqhand = irqhandlers[irq];
255 	prehand = &irqhandlers[irq];
256 
257 	while (irqhand && handler != irqhand) {
258 		prehand = &irqhand;
259 		irqhand = irqhand->ih_next;
260 	}
261 
262 	/* Remove the handler if located */
263 	if (irqhand)
264 		*prehand = irqhand->ih_next;
265 	else
266 		return(-1);
267 
268 	/* Now the handler has been removed from the chain mark is as inactive */
269 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
270 
271 	/* Make sure the head of the handler list is active */
272 	if (irqhandlers[irq])
273 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
274 
275 #ifdef IRQSTATS
276 	/* Get the interrupt name from the head of the list */
277 	if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
278 		char *ptr = _intrnames + (irq * 14);
279 		strcpy(ptr, "             ");
280 		strncpy(ptr, irqhandlers[irq]->ih_name,
281 		    min(strlen(irqhandlers[irq]->ih_name), 13));
282 	} else {
283 		char *ptr = _intrnames + (irq * 14);
284 		sprintf(ptr, "irq %2d     ", irq);
285 	}
286 #endif	/* IRQSTATS */
287 
288 	irq_calculatemasks();
289 
290 	/*
291 	 * Disable the appropriate mask bit if there are no handlers left for
292 	 * this IRQ.
293 	 */
294 	if (irqhandlers[irq] == NULL)
295 		disable_irq(irq);
296 
297 	set_spl_masks();
298 
299 	return(0);
300 }
301 
302 /* adapted from .../i386/isa/isa_machdep.c */
303 /*
304  * Recalculate the interrupt masks from scratch.
305  * We could code special registry and deregistry versions of this function that
306  * would be faster, but the code would be nastier, and we don't expect this to
307  * happen very much anyway.
308  */
309 void
310 irq_calculatemasks()
311 {
312 	int          irq, level;
313 	irqhandler_t *ptr;
314 	int          irqlevel[NIRQS];
315 
316 	/* First, figure out which levels each IRQ uses. */
317 	for (irq = 0; irq < NIRQS; irq++) {
318 		int levels = 0;
319 		for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
320 			levels |= 1 << ptr->ih_level;
321 		irqlevel[irq] = levels;
322 	}
323 
324 	/* Then figure out which IRQs use each level. */
325 	for (level = 0; level < IPL_LEVELS; level++) {
326 		int irqs = 0;
327 		for (irq = 0; irq < NIRQS; irq++)
328 			if (irqlevel[irq] & (1 << level))
329 				irqs |= 1 << irq;
330 		irqmasks[level] = ~irqs;
331 	}
332 
333 	/*
334 	 * Enforce a hierarchy that gives slow devices a better chance at not
335 	 * dropping data.
336 	 */
337 	irqmasks[IPL_NET] &= irqmasks[IPL_BIO];
338 	irqmasks[IPL_TTY] &= irqmasks[IPL_NET];
339 
340 	/*
341 	 * There are tty, network and disk drivers that use free() at interrupt
342 	 * time, so imp > (tty | net | bio).
343 	 */
344 	irqmasks[IPL_VM] &= irqmasks[IPL_TTY];
345 
346 	irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM];
347 
348 	/*
349 	 * Since run queues may be manipulated by both the statclock and tty,
350 	 * network, and disk drivers, statclock > (tty | net | bio).
351 	 */
352 	irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO];
353 
354 	/*
355 	 * IPL_HIGH must block everything that can manipulate a run queue.
356 	 */
357 	irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
358 
359 	/*
360 	 * We need serial drivers to run at the absolute highest priority to
361 	 * avoid overruns, so serial > high.
362 	 */
363 	irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH];
364 }
365 
366 
367 void *
368 intr_claim(irq, level, name, ih_func, ih_arg)
369 	int irq;
370 	int level;
371 	const char *name;
372 	int (*ih_func) __P((void *));
373 	void *ih_arg;
374 {
375 	irqhandler_t *ih;
376 
377 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
378 	if (!ih)
379 		panic("intr_claim(): Cannot malloc handler memory");
380 
381 	ih->ih_level = level;
382 	ih->ih_name = name;
383 	ih->ih_func = ih_func;
384 	ih->ih_arg = ih_arg;
385 	ih->ih_flags = 0;
386 
387 	if (irq_claim(irq, ih) != 0)
388 		return(NULL);
389 	return(ih);
390 }
391 
392 int
393 intr_release(arg)
394 	void *arg;
395 {
396 	irqhandler_t *ih = (irqhandler_t *)arg;
397 
398 	if (irq_release(ih->ih_num, ih) == 0) {
399 		free(ih, M_DEVBUF);
400 		return(0);
401 	}
402 	return(1);
403 }
404 
405 
406 /*
407  * void disable_irq(int irq)
408  *
409  * Disables a specific irq. The irq is removed from the master irq mask
410  */
411 
412 void
413 disable_irq(irq)
414 	int irq;
415 {
416 	u_int oldirqstate;
417 
418 	oldirqstate = disable_interrupts(I32_bit);
419 	current_mask &= ~(1 << irq);
420 	irq_setmasks();
421 	restore_interrupts(oldirqstate);
422 }
423 
424 
425 /*
426  * void enable_irq(int irq)
427  *
428  * Enables a specific irq. The irq is added to the master irq mask
429  * This routine should be used with caution. A handler should already
430  * be installed.
431  */
432 
433 void
434 enable_irq(irq)
435 	int irq;
436 {
437 	u_int oldirqstate;
438 
439 	oldirqstate = disable_interrupts(I32_bit);
440 	current_mask |= (1 << irq);
441 	irq_setmasks();
442 	restore_interrupts(oldirqstate);
443 }
444 
445 
446 /*
447  * void stray_irqhandler(u_int mask)
448  *
449  * Handler for stray interrupts. This gets called if a handler cannot be
450  * found for an interrupt.
451  */
452 
453 void
454 stray_irqhandler(mask)
455 	u_int mask;
456 {
457 	static u_int stray_irqs = 0;
458 
459 	if (++stray_irqs <= 8)
460 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
461 		    stray_irqs >= 8 ? ": stopped logging" : "");
462 }
463