xref: /netbsd/sys/arch/shark/isa/isa_irqhandler.c (revision 6550d01e)
1 /*	$NetBSD: isa_irqhandler.c,v 1.25 2010/12/20 00:25:43 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 1.25 2010/12/20 00:25:43 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 <machine/intr.h>
86 #include <machine/irqhandler.h>
87 #include <machine/cpu.h>
88 
89 irqhandler_t *irqhandlers[NIRQS];
90 
91 u_int current_mask;
92 u_int actual_mask;
93 u_int disabled_mask;
94 u_int irqmasks[NIPL];
95 
96 /* Prototypes */
97 
98 extern void set_spl_masks(void);
99 void irq_calculatemasks(void);
100 void stray_irqhandler(u_int);
101 
102 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b)
103 
104 /*
105  * void irq_init(void)
106  *
107  * Initialise the IRQ/FIQ sub system
108  */
109 
110 void
111 irq_init(void)
112 {
113 	int loop;
114 
115 	/* Clear all the IRQ handlers and the irq block masks */
116 	for (loop = 0; loop < NIRQS; ++loop) {
117 		irqhandlers[loop] = NULL;
118 	}
119 
120 	/*
121 	 * Setup the irqmasks for the different Interrupt Priority Levels
122 	 * We will start with no bits set and these will be updated as handlers
123 	 * are installed at different IPL's.
124 	 */
125 	for (loop = 0; loop < NIPL; ++loop)
126 		irqmasks[loop] = 0;
127 
128 	current_mask = 0x00000000;
129 	disabled_mask = 0x00000000;
130 	actual_mask = 0x00000000;
131 
132 	set_spl_masks();
133 
134 	/* Enable IRQ's and FIQ's */
135 	enable_interrupts(I32_bit | F32_bit);
136 }
137 
138 
139 /*
140  * int irq_claim(int irq, irqhandler_t *handler)
141  *
142  * Enable an IRQ and install a handler for it.
143  */
144 
145 int
146 irq_claim(int irq, irqhandler_t *handler, const char *group, const char *name)
147 {
148 
149 #ifdef DIAGNOSTIC
150 	/* Sanity check */
151 	if (handler == NULL)
152 		panic("NULL interrupt handler");
153 	if (handler->ih_func == NULL)
154 		panic("Interrupt handler does not have a function");
155 #endif	/* DIAGNOSTIC */
156 
157 	/*
158 	 * IRQ_INSTRUCT indicates that we should get the irq number
159 	 * from the irq structure
160 	 */
161 	if (irq == IRQ_INSTRUCT)
162 		irq = handler->ih_num;
163 
164 	/* Make sure the irq number is valid */
165 	if (irq < 0 || irq >= NIRQS)
166 		return(-1);
167 
168 	/* Make sure the level is valid */
169 	if (handler->ih_level < 0 || handler->ih_level >= NIPL)
170     	        return(-1);
171 
172 	/* Attach evcnt */
173 	evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL,
174 	    group, name);
175 
176 	/* Attach handler at top of chain */
177 	handler->ih_next = irqhandlers[irq];
178 	irqhandlers[irq] = handler;
179 
180 	/*
181 	 * Reset the flags for this handler.
182 	 * As the handler is now in the chain mark it as active.
183 	 */
184 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
185 
186 	/*
187 	 * Record the interrupt number for accounting.
188 	 * Done here as the accounting number may not be the same as the
189 	 * IRQ number though for the moment they are
190 	 */
191 	handler->ih_num = irq;
192 
193 	irq_calculatemasks();
194 
195 	enable_irq(irq);
196 	set_spl_masks();
197 	return(0);
198 }
199 
200 
201 /*
202  * int irq_release(int irq, irqhandler_t *handler)
203  *
204  * Disable an IRQ and remove a handler for it.
205  */
206 
207 int
208 irq_release(int irq, irqhandler_t *handler)
209 {
210 	irqhandler_t *irqhand;
211 	irqhandler_t **prehand;
212 
213 	/*
214 	 * IRQ_INSTRUCT indicates that we should get the irq number
215 	 * from the irq structure
216 	 */
217 	if (irq == IRQ_INSTRUCT)
218 		irq = handler->ih_num;
219 
220 	/* Make sure the irq number is valid */
221 	if (irq < 0 || irq >= NIRQS)
222 		return(-1);
223 
224 	/* Locate the handler */
225 	prehand = &irqhandlers[irq];
226 	irqhand = *prehand;
227 
228 	while (irqhand && handler != irqhand) {
229 		prehand = &irqhand->ih_next;
230 		irqhand = *prehand;
231 	}
232 
233 	/* Remove the handler if located */
234 	if (irqhand)
235 		*prehand = irqhand->ih_next;
236 	else
237 		return(-1);
238 
239 	/* The handler has been removed from the chain so mark it as inactive */
240 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
241 
242 	/* Make sure the head of the handler list is active */
243 	if (irqhandlers[irq])
244 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
245 
246 	evcnt_detach(&irqhand->ih_ev);
247 
248 	irq_calculatemasks();
249 
250 	/*
251 	 * Disable the appropriate mask bit if there are no handlers left for
252 	 * this IRQ.
253 	 */
254 	if (irqhandlers[irq] == NULL)
255 		disable_irq(irq);
256 
257 	set_spl_masks();
258 
259 	return(0);
260 }
261 
262 /* adapted from .../i386/isa/isa_machdep.c */
263 /*
264  * Recalculate the interrupt masks from scratch.
265  * We could code special registry and deregistry versions of this function that
266  * would be faster, but the code would be nastier, and we don't expect this to
267  * happen very much anyway.
268  */
269 void
270 irq_calculatemasks(void)
271 {
272 	int          irq, level;
273 	irqhandler_t *ptr;
274 	int          irqlevel[NIRQS];
275 
276 	/* First, figure out which levels each IRQ uses. */
277 	for (irq = 0; irq < NIRQS; irq++) {
278 		int levels = 0;
279 		for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
280 			levels |= 1 << ptr->ih_level;
281 		irqlevel[irq] = levels;
282 	}
283 
284 	/* Then figure out which IRQs use each level. */
285 	for (level = 0; level < NIPL; level++) {
286 		int irqs = 0;
287 		for (irq = 0; irq < NIRQS; irq++)
288 			if (irqlevel[irq] & (1 << level))
289 				irqs |= 1 << irq;
290 		irqmasks[level] = ~irqs;
291 	}
292 
293 	/*
294 	 * Enforce a hierarchy that gives slow devices a better chance at not
295 	 * dropping data.
296 	 */
297 	KASSERT(irqmasks[IPL_NONE] == ~0);
298 	irqmasks[IPL_SOFTCLOCK] &= irqmasks[IPL_NONE];
299 	irqmasks[IPL_SOFTBIO] &= irqmasks[IPL_SOFTCLOCK];
300 	irqmasks[IPL_SOFTNET] &= irqmasks[IPL_SOFTBIO];
301 	irqmasks[IPL_SOFTSERIAL] &= irqmasks[IPL_SOFTNET];
302 	irqmasks[IPL_VM] &= irqmasks[IPL_SOFTSERIAL];
303 	irqmasks[IPL_CLOCK] &= irqmasks[IPL_VM];
304 	irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
305 }
306 
307 
308 void *
309 intr_claim(int irq, int level, int (*ih_func)(void *), void *ih_arg, const char *group, const char *name)
310 {
311 	irqhandler_t *ih;
312 
313 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT | M_ZERO);
314 	if (!ih)
315 		panic("intr_claim(): Cannot malloc handler memory");
316 
317 	ih->ih_level = level;
318 	ih->ih_func = ih_func;
319 	ih->ih_arg = ih_arg;
320 	ih->ih_flags = 0;
321 
322 	if (irq_claim(irq, ih, group, name) != 0)
323 		return(NULL);
324 
325 	return(ih);
326 }
327 
328 int
329 intr_release(void *arg)
330 {
331 	irqhandler_t *ih = (irqhandler_t *)arg;
332 
333 	if (irq_release(ih->ih_num, ih) == 0) {
334 		free(ih, M_DEVBUF);
335 		return(0);
336 	}
337 	return(1);
338 }
339 
340 
341 /*
342  * void disable_irq(int irq)
343  *
344  * Disables a specific irq. The irq is removed from the master irq mask
345  */
346 
347 void
348 disable_irq(int irq)
349 {
350 	u_int oldirqstate;
351 
352 	oldirqstate = disable_interrupts(I32_bit);
353 	current_mask &= ~(1 << irq);
354 	irq_setmasks();
355 	restore_interrupts(oldirqstate);
356 }
357 
358 
359 /*
360  * void enable_irq(int irq)
361  *
362  * Enables a specific irq. The irq is added to the master irq mask
363  * This routine should be used with caution. A handler should already
364  * be installed.
365  */
366 
367 void
368 enable_irq(int irq)
369 {
370 	u_int oldirqstate;
371 
372 	oldirqstate = disable_interrupts(I32_bit);
373 	current_mask |= (1 << irq);
374 	irq_setmasks();
375 	restore_interrupts(oldirqstate);
376 }
377 
378 
379 /*
380  * void stray_irqhandler(u_int mask)
381  *
382  * Handler for stray interrupts. This gets called if a handler cannot be
383  * found for an interrupt.
384  */
385 
386 void
387 stray_irqhandler(u_int mask)
388 {
389 	static u_int stray_irqs = 0;
390 
391 	if (++stray_irqs <= 8)
392 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
393 		    stray_irqs >= 8 ? ": stopped logging" : "");
394 }
395