xref: /netbsd-src/sys/arch/shark/isa/isa_irqhandler.c (revision 4b293a84e10d4252c834c13e4cd7dd403a91ff9c)
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