xref: /netbsd-src/sys/arch/shark/isa/isa_irqhandler.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: isa_irqhandler.c,v 1.21 2008/04/27 18:58:47 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 1.21 2008/04/27 18:58:47 matt 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 u_int current_mask;
94 u_int actual_mask;
95 u_int disabled_mask;
96 u_int irqmasks[NIPL];
97 
98 /* Prototypes */
99 
100 extern void set_spl_masks(void);
101 void irq_calculatemasks(void);
102 void stray_irqhandler(u_int);
103 
104 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b)
105 
106 /*
107  * void irq_init(void)
108  *
109  * Initialise the IRQ/FIQ sub system
110  */
111 
112 void
113 irq_init()
114 {
115 	int loop;
116 
117 	/* Clear all the IRQ handlers and the irq block masks */
118 	for (loop = 0; loop < NIRQS; ++loop) {
119 		irqhandlers[loop] = NULL;
120 	}
121 
122 	/*
123 	 * Setup the irqmasks for the different Interrupt Priority Levels
124 	 * We will start with no bits set and these will be updated as handlers
125 	 * are installed at different IPL's.
126 	 */
127 	for (loop = 0; loop < NIPL; ++loop)
128 		irqmasks[loop] = 0;
129 
130 	current_mask = 0x00000000;
131 	disabled_mask = 0x00000000;
132 	actual_mask = 0x00000000;
133 
134 	set_spl_masks();
135 
136 	/* Enable IRQ's and FIQ's */
137 	enable_interrupts(I32_bit | F32_bit);
138 }
139 
140 
141 /*
142  * int irq_claim(int irq, irqhandler_t *handler)
143  *
144  * Enable an IRQ and install a handler for it.
145  */
146 
147 int
148 irq_claim(irq, handler, group, name)
149 	int irq;
150 	irqhandler_t *handler;
151 	const char *group;
152 	const char *name;
153 {
154 
155 #ifdef DIAGNOSTIC
156 	/* Sanity check */
157 	if (handler == NULL)
158 		panic("NULL interrupt handler");
159 	if (handler->ih_func == NULL)
160 		panic("Interrupt handler does not have a function");
161 #endif	/* DIAGNOSTIC */
162 
163 	/*
164 	 * IRQ_INSTRUCT indicates that we should get the irq number
165 	 * from the irq structure
166 	 */
167 	if (irq == IRQ_INSTRUCT)
168 		irq = handler->ih_num;
169 
170 	/* Make sure the irq number is valid */
171 	if (irq < 0 || irq >= NIRQS)
172 		return(-1);
173 
174 	/* Make sure the level is valid */
175 	if (handler->ih_level < 0 || handler->ih_level >= NIPL)
176     	        return(-1);
177 
178 	/* Attach evcnt */
179 	evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL,
180 	    group, name);
181 
182 	/* Attach handler at top of chain */
183 	handler->ih_next = irqhandlers[irq];
184 	irqhandlers[irq] = handler;
185 
186 	/*
187 	 * Reset the flags for this handler.
188 	 * As the handler is now in the chain mark it as active.
189 	 */
190 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
191 
192 	/*
193 	 * Record the interrupt number for accounting.
194 	 * Done here as the accounting number may not be the same as the
195 	 * IRQ number though for the moment they are
196 	 */
197 	handler->ih_num = irq;
198 
199 	irq_calculatemasks();
200 
201 	enable_irq(irq);
202 	set_spl_masks();
203 	return(0);
204 }
205 
206 
207 /*
208  * int irq_release(int irq, irqhandler_t *handler)
209  *
210  * Disable an IRQ and remove a handler for it.
211  */
212 
213 int
214 irq_release(irq, handler)
215 	int irq;
216 	irqhandler_t *handler;
217 {
218 	irqhandler_t *irqhand;
219 	irqhandler_t **prehand;
220 
221 	/*
222 	 * IRQ_INSTRUCT indicates that we should get the irq number
223 	 * from the irq structure
224 	 */
225 	if (irq == IRQ_INSTRUCT)
226 		irq = handler->ih_num;
227 
228 	/* Make sure the irq number is valid */
229 	if (irq < 0 || irq >= NIRQS)
230 		return(-1);
231 
232 	/* Locate the handler */
233 	prehand = &irqhandlers[irq];
234 	irqhand = *prehand;
235 
236 	while (irqhand && handler != irqhand) {
237 		prehand = &irqhand->ih_next;
238 		irqhand = *prehand;
239 	}
240 
241 	/* Remove the handler if located */
242 	if (irqhand)
243 		*prehand = irqhand->ih_next;
244 	else
245 		return(-1);
246 
247 	/* The handler has been removed from the chain so mark it as inactive */
248 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
249 
250 	/* Make sure the head of the handler list is active */
251 	if (irqhandlers[irq])
252 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
253 
254 	evcnt_detach(&irqhand->ih_ev);
255 
256 	irq_calculatemasks();
257 
258 	/*
259 	 * Disable the appropriate mask bit if there are no handlers left for
260 	 * this IRQ.
261 	 */
262 	if (irqhandlers[irq] == NULL)
263 		disable_irq(irq);
264 
265 	set_spl_masks();
266 
267 	return(0);
268 }
269 
270 /* adapted from .../i386/isa/isa_machdep.c */
271 /*
272  * Recalculate the interrupt masks from scratch.
273  * We could code special registry and deregistry versions of this function that
274  * would be faster, but the code would be nastier, and we don't expect this to
275  * happen very much anyway.
276  */
277 void
278 irq_calculatemasks()
279 {
280 	int          irq, level;
281 	irqhandler_t *ptr;
282 	int          irqlevel[NIRQS];
283 
284 	/* First, figure out which levels each IRQ uses. */
285 	for (irq = 0; irq < NIRQS; irq++) {
286 		int levels = 0;
287 		for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
288 			levels |= 1 << ptr->ih_level;
289 		irqlevel[irq] = levels;
290 	}
291 
292 	/* Then figure out which IRQs use each level. */
293 	for (level = 0; level < NIPL; level++) {
294 		int irqs = 0;
295 		for (irq = 0; irq < NIRQS; irq++)
296 			if (irqlevel[irq] & (1 << level))
297 				irqs |= 1 << irq;
298 		irqmasks[level] = ~irqs;
299 	}
300 
301 	/*
302 	 * Enforce a hierarchy that gives slow devices a better chance at not
303 	 * dropping data.
304 	 */
305 	KASSERT(irqmasks[IPL_NONE] == ~0);
306 	irqmasks[IPL_SOFTCLOCK] &= irqmasks[IPL_NONE];
307 	irqmasks[IPL_SOFTBIO] &= irqmasks[IPL_SOFTCLOCK];
308 	irqmasks[IPL_SOFTNET] &= irqmasks[IPL_SOFTBIO];
309 	irqmasks[IPL_SOFTSERIAL] &= irqmasks[IPL_SOFTNET];
310 	irqmasks[IPL_VM] &= irqmasks[IPL_SOFTSERIAL];
311 	irqmasks[IPL_CLOCK] &= irqmasks[IPL_VM];
312 	irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
313 }
314 
315 
316 void *
317 intr_claim(irq, level, ih_func, ih_arg, group, name)
318 	int irq;
319 	int level;
320 	int (*ih_func)(void *);
321 	void *ih_arg;
322 	const char *group;
323 	const char *name;
324 {
325 	irqhandler_t *ih;
326 
327 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT | M_ZERO);
328 	if (!ih)
329 		panic("intr_claim(): Cannot malloc handler memory");
330 
331 	ih->ih_level = level;
332 	ih->ih_func = ih_func;
333 	ih->ih_arg = ih_arg;
334 	ih->ih_flags = 0;
335 
336 	if (irq_claim(irq, ih, group, name) != 0)
337 		return(NULL);
338 
339 	return(ih);
340 }
341 
342 int
343 intr_release(arg)
344 	void *arg;
345 {
346 	irqhandler_t *ih = (irqhandler_t *)arg;
347 
348 	if (irq_release(ih->ih_num, ih) == 0) {
349 		free(ih, M_DEVBUF);
350 		return(0);
351 	}
352 	return(1);
353 }
354 
355 
356 /*
357  * void disable_irq(int irq)
358  *
359  * Disables a specific irq. The irq is removed from the master irq mask
360  */
361 
362 void
363 disable_irq(irq)
364 	int irq;
365 {
366 	u_int oldirqstate;
367 
368 	oldirqstate = disable_interrupts(I32_bit);
369 	current_mask &= ~(1 << irq);
370 	irq_setmasks();
371 	restore_interrupts(oldirqstate);
372 }
373 
374 
375 /*
376  * void enable_irq(int irq)
377  *
378  * Enables a specific irq. The irq is added to the master irq mask
379  * This routine should be used with caution. A handler should already
380  * be installed.
381  */
382 
383 void
384 enable_irq(irq)
385 	int irq;
386 {
387 	u_int oldirqstate;
388 
389 	oldirqstate = disable_interrupts(I32_bit);
390 	current_mask |= (1 << irq);
391 	irq_setmasks();
392 	restore_interrupts(oldirqstate);
393 }
394 
395 
396 /*
397  * void stray_irqhandler(u_int mask)
398  *
399  * Handler for stray interrupts. This gets called if a handler cannot be
400  * found for an interrupt.
401  */
402 
403 void
404 stray_irqhandler(mask)
405 	u_int mask;
406 {
407 	static u_int stray_irqs = 0;
408 
409 	if (++stray_irqs <= 8)
410 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
411 		    stray_irqs >= 8 ? ": stopped logging" : "");
412 }
413