xref: /netbsd-src/sys/arch/arm/iomd/iomd_irqhandler.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: iomd_irqhandler.c,v 1.22 2014/10/25 10:58:12 skrll Exp $	*/
2 
3 /*
4  * Copyright (c) 1994-1998 Mark Brinicombe.
5  * Copyright (c) 1994 Brini.
6  * All rights reserved.
7  *
8  * This code is derived from software written for Brini by Mark Brinicombe
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by Mark Brinicombe
21  *	for the NetBSD Project.
22  * 4. The name of the company nor the name of the author may be used to
23  *    endorse or promote products derived from this software without specific
24  *    prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  *
37  * IRQ/FIQ initialisation, claim, release and handler routines
38  *
39  *	from: irqhandler.c,v 1.14 1997/04/02 21:52:19 christos Exp $
40  */
41 
42 #include <sys/cdefs.h>
43 __KERNEL_RCSID(0, "$NetBSD: iomd_irqhandler.c,v 1.22 2014/10/25 10:58:12 skrll Exp $");
44 
45 #include "opt_irqstats.h"
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/syslog.h>
50 #include <sys/malloc.h>
51 
52 #include <arm/cpufunc.h>
53 #include <arm/iomd/iomdreg.h>
54 #include <arm/iomd/iomdvar.h>
55 
56 #include <machine/intr.h>
57 #include <machine/cpu.h>
58 
59 irqhandler_t *irqhandlers[NIRQS];
60 
61 u_int current_mask;
62 u_int actual_mask;
63 u_int disabled_mask;
64 u_int irqmasks[NIPL];
65 
66 extern char *_intrnames;
67 
68 /* Prototypes */
69 
70 extern void set_spl_masks(void);
71 
72 /*
73  * void irq_init(void)
74  *
75  * Initialise the IRQ/FIQ sub system
76  */
77 
78 void
79 irq_init(void)
80 {
81 	int loop;
82 
83 	/* Clear all the IRQ handlers and the irq block masks */
84 	for (loop = 0; loop < NIRQS; ++loop)
85 		irqhandlers[loop] = NULL;
86 
87 	/* Clear the IRQ/FIQ masks in the IOMD */
88 	IOMD_WRITE_BYTE(IOMD_IRQMSKA, 0x00);
89 	IOMD_WRITE_BYTE(IOMD_IRQMSKB, 0x00);
90 
91 	switch (IOMD_ID) {
92 	case RPC600_IOMD_ID:
93 		break;
94 	case ARM7500_IOC_ID:
95 	case ARM7500FE_IOC_ID:
96 		IOMD_WRITE_BYTE(IOMD_IRQMSKC, 0x00);
97 		IOMD_WRITE_BYTE(IOMD_IRQMSKD, 0x00);
98 		break;
99 	default:
100 		printf("Unknown IOMD id (%d) found in irq_init()\n", IOMD_ID);
101 	}
102 
103 	IOMD_WRITE_BYTE(IOMD_FIQMSK, 0x00);
104 	IOMD_WRITE_BYTE(IOMD_DMAMSK, 0x00);
105 
106 	/*
107 	 * Setup the irqmasks for the different Interrupt Priority Levels
108 	 * We will start with no bits set and these will be updated as handlers
109 	 * are installed at different IPL's.
110 	 */
111 	for (loop = 0; loop < NIPL; ++loop)
112 		irqmasks[loop] = 0;
113 
114 	current_mask = 0x00000000;
115 	disabled_mask = 0x00000000;
116 	actual_mask = 0x00000000;
117 
118 	set_spl_masks();
119 
120 	/* Enable IRQ's and FIQ's */
121 	enable_interrupts(I32_bit | F32_bit);
122 }
123 
124 
125 /*
126  * int irq_claim(int irq, irqhandler_t *handler)
127  *
128  * Enable an IRQ and install a handler for it.
129  */
130 
131 int
132 irq_claim(int irq, irqhandler_t *handler)
133 {
134 	int level;
135 	u_int oldirqstate;
136 
137 #ifdef DIAGNOSTIC
138 	/* Sanity check */
139 	if (handler == NULL)
140 		panic("NULL interrupt handler");
141 	if (handler->ih_func == NULL)
142 		panic("Interrupt handler does not have a function");
143 #endif	/* DIAGNOSTIC */
144 
145 	/*
146 	 * IRQ_INSTRUCT indicates that we should get the irq number
147 	 * from the irq structure
148 	 */
149 	if (irq == IRQ_INSTRUCT)
150 		irq = handler->ih_num;
151 
152 	/* Make sure the irq number is valid */
153 	if (irq < 0 || irq >= NIRQS)
154 		return -1;
155 
156 	/* Make sure the level is valid */
157 	if (handler->ih_level < 0 || handler->ih_level >= NIPL)
158     	        return -1;
159 
160 	oldirqstate = disable_interrupts(I32_bit);
161 
162 	/* Attach handler at top of chain */
163 	handler->ih_next = irqhandlers[irq];
164 	irqhandlers[irq] = handler;
165 
166 	/*
167 	 * Reset the flags for this handler.
168 	 * As the handler is now in the chain mark it as active.
169 	 */
170 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
171 
172 	/*
173 	 * Record the interrupt number for accounting.
174 	 * Done here as the accounting number may not be the same as the
175 	 * IRQ number though for the moment they are
176 	 */
177 	handler->ih_num = irq;
178 
179 #ifdef IRQSTATS
180 	/* Get the interrupt name from the head of the list */
181 	char *iptr = _intrnames + (irq * 14);
182 	if (handler->ih_name) {
183 		strlcpy(iptr, handler->ih_name, 14);
184 	} else {
185 		snprintf(iptr, 14, "irq %2d     ", irq);
186 	}
187 #endif	/* IRQSTATS */
188 
189 	/*
190 	 * Update the irq masks.
191 	 * Find the lowest interrupt priority on the irq chain.
192 	 * Interrupt is allowable at priorities lower than this.
193 	 * If ih_level is out of range then don't bother to update
194 	 * the masks.
195 	 */
196 	if (handler->ih_level >= 0 && handler->ih_level < NIPL) {
197 		irqhandler_t *ptr;
198 
199 		/*
200 		 * Find the lowest interrupt priority on the irq chain.
201 		 * Interrupt is allowable at priorities lower than this.
202 		 */
203 		ptr = irqhandlers[irq];
204 		if (ptr) {
205 			int max_level;
206 
207 			level = ptr->ih_level - 1;
208 			max_level = ptr->ih_level - 1;
209 			while (ptr) {
210 				if (ptr->ih_level - 1 < level)
211 					level = ptr->ih_level - 1;
212 				else if (ptr->ih_level - 1 > max_level)
213 					max_level = ptr->ih_level - 1;
214 				ptr = ptr->ih_next;
215 			}
216 			/* Clear out any levels that we cannot now allow */
217 			while (max_level >=0 && max_level > level) {
218 				irqmasks[max_level] &= ~(1 << irq);
219 				--max_level;
220 			}
221 			while (level >= 0) {
222 				irqmasks[level] |= (1 << irq);
223 				--level;
224 			}
225 		}
226 
227 #include "sl.h"
228 #include "ppp.h"
229 #if NSL > 0 || NPPP > 0
230 		/* In the presence of SLIP or PPP, splimp > spltty. */
231 		irqmasks[IPL_NET] &= irqmasks[IPL_TTY];
232 #endif
233 	}
234 
235 	enable_irq(irq);
236 	set_spl_masks();
237 	restore_interrupts(oldirqstate);
238 
239 	return 0;
240 }
241 
242 
243 /*
244  * int irq_release(int irq, irqhandler_t *handler)
245  *
246  * Disable an IRQ and remove a handler for it.
247  */
248 
249 int
250 irq_release(int irq, irqhandler_t *handler)
251 {
252 	int level;
253 	irqhandler_t *irqhand;
254 	irqhandler_t **prehand;
255 
256 	/*
257 	 * IRQ_INSTRUCT indicates that we should get the irq number
258 	 * from the irq structure
259 	 */
260 	if (irq == IRQ_INSTRUCT)
261 		irq = handler->ih_num;
262 
263 	/* Make sure the irq number is valid */
264 	if (irq < 0 || irq >= NIRQS)
265 		return(-1);
266 
267 	/* Locate the handler */
268 	irqhand = irqhandlers[irq];
269 	prehand = &irqhandlers[irq];
270 
271 	while (irqhand && handler != irqhand) {
272 		prehand = &irqhand->ih_next;
273 		irqhand = irqhand->ih_next;
274 	}
275 
276 	/* Remove the handler if located */
277 	if (irqhand)
278 		*prehand = irqhand->ih_next;
279 	else
280 		return -1;
281 
282 	/* Now the handler has been removed from the chain mark is as inactive */
283 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
284 
285 	/* Make sure the head of the handler list is active */
286 	if (irqhandlers[irq])
287 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
288 
289 #ifdef IRQSTATS
290 	/* Get the interrupt name from the head of the list */
291 	char *iptr = _intrnames + (irq * 14);
292 	if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
293 		strlcpy(iptr, irqhandlers[irq]->ih_name, 14);
294 	} else {
295 		snprintf(iptr, 14, "irq %2d     ", irq);
296 	}
297 #endif	/* IRQSTATS */
298 
299 	/*
300 	 * Update the irq masks.
301 	 * If ih_level is out of range then don't bother to update
302 	 * the masks.
303 	 */
304 	if (handler->ih_level >= 0 && handler->ih_level < NIPL) {
305 		irqhandler_t *ptr;
306 
307 		/* Clean the bit from all the masks */
308 		for (level = 0; level < NIPL; ++level)
309 			irqmasks[level] &= ~(1 << irq);
310 
311 		/*
312 		 * Find the lowest interrupt priority on the irq chain.
313 		 * Interrupt is allowable at priorities lower than this.
314 		 */
315 		ptr = irqhandlers[irq];
316 		if (ptr) {
317 			level = ptr->ih_level - 1;
318 			while (ptr) {
319 				if (ptr->ih_level - 1 < level)
320 					level = ptr->ih_level - 1;
321 				ptr = ptr->ih_next;
322 			}
323 			while (level >= 0) {
324 				irqmasks[level] |= (1 << irq);
325 				--level;
326 			}
327 		}
328 	}
329 
330 	/*
331 	 * Disable the appropriate mask bit if there are no handlers left for
332 	 * this IRQ.
333 	 */
334 	if (irqhandlers[irq] == NULL)
335 		disable_irq(irq);
336 
337 	set_spl_masks();
338 
339 	return 0;
340 }
341 
342 
343 void *
344 intr_claim(int irq, int level, const char *name, int (*ih_func)(void *),
345     void *ih_arg)
346 {
347 	irqhandler_t *ih;
348 
349 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
350 	if (!ih)
351 		panic("intr_claim(): Cannot malloc handler memory");
352 
353 	ih->ih_level = level;
354 	ih->ih_name = name;
355 	ih->ih_func = ih_func;
356 	ih->ih_arg = ih_arg;
357 	ih->ih_flags = 0;
358 
359 	if (irq_claim(irq, ih) != 0) {
360 		free(ih, M_DEVBUF);
361 		return NULL;
362 	}
363 	return ih;
364 }
365 
366 
367 int
368 intr_release(void *arg)
369 {
370 	irqhandler_t *ih = (irqhandler_t *)arg;
371 
372 	if (irq_release(ih->ih_num, ih) == 0) {
373 		free(ih, M_DEVBUF);
374 		return 0 ;
375 	}
376 	return 1;
377 }
378 
379 #if 0
380 u_int
381 disable_interrupts(u_int mask)
382 {
383 	u_int cpsr;
384 
385 	cpsr = SetCPSR(mask, mask);
386 	return cpsr;
387 }
388 
389 
390 u_int
391 restore_interrupts(u_int old_cpsr)
392 {
393 	int mask = I32_bit | F32_bit;
394 
395 	return SetCPSR(mask, old_cpsr & mask);
396 }
397 
398 
399 u_int
400 enable_interrupts(u_int mask)
401 {
402 
403 	return SetCPSR(mask, 0);
404 }
405 #endif
406 
407 /*
408  * void disable_irq(int irq)
409  *
410  * Disables a specific irq. The irq is removed from the master irq mask
411  */
412 
413 void
414 disable_irq(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(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(u_int mask)
454 {
455 	static u_int stray_irqs = 0;
456 
457 	if (++stray_irqs <= 8)
458 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
459 		    stray_irqs >= 8 ? ": stopped logging" : "");
460 }
461