xref: /netbsd-src/sys/arch/arm/iomd/iomd_irqhandler.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: iomd_irqhandler.c,v 1.17 2008/04/27 18:58:44 matt 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 1.17 2008/04/27 18:58:44 matt 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 #include <uvm/uvm_extern.h>
52 
53 #include <arm/iomd/iomdreg.h>
54 #include <arm/iomd/iomdvar.h>
55 
56 #include <machine/intr.h>
57 #include <machine/cpu.h>
58 #include <arm/arm32/katelib.h>
59 
60 irqhandler_t *irqhandlers[NIRQS];
61 
62 u_int current_mask;
63 u_int actual_mask;
64 u_int disabled_mask;
65 u_int irqmasks[NIPL];
66 
67 extern char *_intrnames;
68 
69 /* Prototypes */
70 
71 extern void set_spl_masks(void);
72 
73 /*
74  * void irq_init(void)
75  *
76  * Initialise the IRQ/FIQ sub system
77  */
78 
79 void
80 irq_init(void)
81 {
82 	int loop;
83 
84 	/* Clear all the IRQ handlers and the irq block masks */
85 	for (loop = 0; loop < NIRQS; ++loop)
86 		irqhandlers[loop] = NULL;
87 
88 	/* Clear the IRQ/FIQ masks in the IOMD */
89 	IOMD_WRITE_BYTE(IOMD_IRQMSKA, 0x00);
90 	IOMD_WRITE_BYTE(IOMD_IRQMSKB, 0x00);
91 
92 	switch (IOMD_ID) {
93 	case RPC600_IOMD_ID:
94 		break;
95 	case ARM7500_IOC_ID:
96 	case ARM7500FE_IOC_ID:
97 		IOMD_WRITE_BYTE(IOMD_IRQMSKC, 0x00);
98 		IOMD_WRITE_BYTE(IOMD_IRQMSKD, 0x00);
99 		break;
100 	default:
101 		printf("Unknown IOMD id (%d) found in irq_init()\n", IOMD_ID);
102 	}
103 
104 	IOMD_WRITE_BYTE(IOMD_FIQMSK, 0x00);
105 	IOMD_WRITE_BYTE(IOMD_DMAMSK, 0x00);
106 
107 	/*
108 	 * Setup the irqmasks for the different Interrupt Priority Levels
109 	 * We will start with no bits set and these will be updated as handlers
110 	 * are installed at different IPL's.
111 	 */
112 	for (loop = 0; loop < NIPL; ++loop)
113 		irqmasks[loop] = 0;
114 
115 	current_mask = 0x00000000;
116 	disabled_mask = 0x00000000;
117 	actual_mask = 0x00000000;
118 
119 	set_spl_masks();
120 
121 	/* Enable IRQ's and FIQ's */
122 	enable_interrupts(I32_bit | F32_bit);
123 }
124 
125 
126 /*
127  * int irq_claim(int irq, irqhandler_t *handler)
128  *
129  * Enable an IRQ and install a handler for it.
130  */
131 
132 int
133 irq_claim(int irq, irqhandler_t *handler)
134 {
135 	int level;
136 	u_int oldirqstate;
137 
138 #ifdef DIAGNOSTIC
139 	/* Sanity check */
140 	if (handler == NULL)
141 		panic("NULL interrupt handler");
142 	if (handler->ih_func == NULL)
143 		panic("Interrupt handler does not have a function");
144 #endif	/* DIAGNOSTIC */
145 
146 	/*
147 	 * IRQ_INSTRUCT indicates that we should get the irq number
148 	 * from the irq structure
149 	 */
150 	if (irq == IRQ_INSTRUCT)
151 		irq = handler->ih_num;
152 
153 	/* Make sure the irq number is valid */
154 	if (irq < 0 || irq >= NIRQS)
155 		return -1;
156 
157 	/* Make sure the level is valid */
158 	if (handler->ih_level < 0 || handler->ih_level >= NIPL)
159     	        return -1;
160 
161 	oldirqstate = disable_interrupts(I32_bit);
162 
163 	/* Attach handler at top of chain */
164 	handler->ih_next = irqhandlers[irq];
165 	irqhandlers[irq] = handler;
166 
167 	/*
168 	 * Reset the flags for this handler.
169 	 * As the handler is now in the chain mark it as active.
170 	 */
171 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
172 
173 	/*
174 	 * Record the interrupt number for accounting.
175 	 * Done here as the accounting number may not be the same as the
176 	 * IRQ number though for the moment they are
177 	 */
178 	handler->ih_num = irq;
179 
180 #ifdef IRQSTATS
181 	/* Get the interrupt name from the head of the list */
182 	if (handler->ih_name) {
183 		char *ptr = _intrnames + (irq * 14);
184 		strcpy(ptr, "             ");
185 		strncpy(ptr, handler->ih_name,
186 		    min(strlen(handler->ih_name), 13));
187 	} else {
188 		char *ptr = _intrnames + (irq * 14);
189 		sprintf(ptr, "irq %2d     ", irq);
190 	}
191 #endif	/* IRQSTATS */
192 
193 	/*
194 	 * Update the irq masks.
195 	 * Find the lowest interrupt priority on the irq chain.
196 	 * Interrupt is allowable at priorities lower than this.
197 	 * If ih_level is out of range then don't bother to update
198 	 * the masks.
199 	 */
200 	if (handler->ih_level >= 0 && handler->ih_level < NIPL) {
201 		irqhandler_t *ptr;
202 
203 		/*
204 		 * Find the lowest interrupt priority on the irq chain.
205 		 * Interrupt is allowable at priorities lower than this.
206 		 */
207 		ptr = irqhandlers[irq];
208 		if (ptr) {
209 			int max_level;
210 
211 			level = ptr->ih_level - 1;
212 			max_level = ptr->ih_level - 1;
213 			while (ptr) {
214 				if (ptr->ih_level - 1 < level)
215 					level = ptr->ih_level - 1;
216 				else if (ptr->ih_level - 1 > max_level)
217 					max_level = ptr->ih_level - 1;
218 				ptr = ptr->ih_next;
219 			}
220 			/* Clear out any levels that we cannot now allow */
221 			while (max_level >=0 && max_level > level) {
222 				irqmasks[max_level] &= ~(1 << irq);
223 				--max_level;
224 			}
225 			while (level >= 0) {
226 				irqmasks[level] |= (1 << irq);
227 				--level;
228 			}
229 		}
230 
231 #include "sl.h"
232 #include "ppp.h"
233 #if NSL > 0 || NPPP > 0
234 		/* In the presence of SLIP or PPP, splimp > spltty. */
235 		irqmasks[IPL_NET] &= irqmasks[IPL_TTY];
236 #endif
237 	}
238 
239 	enable_irq(irq);
240 	set_spl_masks();
241 	restore_interrupts(oldirqstate);
242 
243 	return 0;
244 }
245 
246 
247 /*
248  * int irq_release(int irq, irqhandler_t *handler)
249  *
250  * Disable an IRQ and remove a handler for it.
251  */
252 
253 int
254 irq_release(int irq, irqhandler_t *handler)
255 {
256 	int level;
257 	irqhandler_t *irqhand;
258 	irqhandler_t **prehand;
259 #ifdef IRQSTATS
260 	extern char *_intrnames;
261 #endif
262 
263 	/*
264 	 * IRQ_INSTRUCT indicates that we should get the irq number
265 	 * from the irq structure
266 	 */
267 	if (irq == IRQ_INSTRUCT)
268 		irq = handler->ih_num;
269 
270 	/* Make sure the irq number is valid */
271 	if (irq < 0 || irq >= NIRQS)
272 		return(-1);
273 
274 	/* Locate the handler */
275 	irqhand = irqhandlers[irq];
276 	prehand = &irqhandlers[irq];
277 
278 	while (irqhand && handler != irqhand) {
279 		prehand = &irqhand->ih_next;
280 		irqhand = irqhand->ih_next;
281 	}
282 
283 	/* Remove the handler if located */
284 	if (irqhand)
285 		*prehand = irqhand->ih_next;
286 	else
287 		return -1;
288 
289 	/* Now the handler has been removed from the chain mark is as inactive */
290 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
291 
292 	/* Make sure the head of the handler list is active */
293 	if (irqhandlers[irq])
294 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
295 
296 #ifdef IRQSTATS
297 	/* Get the interrupt name from the head of the list */
298 	if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
299 		char *ptr = _intrnames + (irq * 14);
300 		strcpy(ptr, "             ");
301 		strncpy(ptr, irqhandlers[irq]->ih_name,
302 		    min(strlen(irqhandlers[irq]->ih_name), 13));
303 	} else {
304 		char *ptr = _intrnames + (irq * 14);
305 		sprintf(ptr, "irq %2d     ", irq);
306 	}
307 #endif	/* IRQSTATS */
308 
309 	/*
310 	 * Update the irq masks.
311 	 * If ih_level is out of range then don't bother to update
312 	 * the masks.
313 	 */
314 	if (handler->ih_level >= 0 && handler->ih_level < NIPL) {
315 		irqhandler_t *ptr;
316 
317 		/* Clean the bit from all the masks */
318 		for (level = 0; level < NIPL; ++level)
319 			irqmasks[level] &= ~(1 << irq);
320 
321 		/*
322 		 * Find the lowest interrupt priority on the irq chain.
323 		 * Interrupt is allowable at priorities lower than this.
324 		 */
325 		ptr = irqhandlers[irq];
326 		if (ptr) {
327 			level = ptr->ih_level - 1;
328 			while (ptr) {
329 				if (ptr->ih_level - 1 < level)
330 					level = ptr->ih_level - 1;
331 				ptr = ptr->ih_next;
332 			}
333 			while (level >= 0) {
334 				irqmasks[level] |= (1 << irq);
335 				--level;
336 			}
337 		}
338 	}
339 
340 	/*
341 	 * Disable the appropriate mask bit if there are no handlers left for
342 	 * this IRQ.
343 	 */
344 	if (irqhandlers[irq] == NULL)
345 		disable_irq(irq);
346 
347 	set_spl_masks();
348 
349 	return 0;
350 }
351 
352 
353 void *
354 intr_claim(int irq, int level, const char *name, int (*ih_func)(void *),
355     void *ih_arg)
356 {
357 	irqhandler_t *ih;
358 
359 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
360 	if (!ih)
361 		panic("intr_claim(): Cannot malloc handler memory");
362 
363 	ih->ih_level = level;
364 	ih->ih_name = name;
365 	ih->ih_func = ih_func;
366 	ih->ih_arg = ih_arg;
367 	ih->ih_flags = 0;
368 
369 	if (irq_claim(irq, ih) != 0)
370 		return NULL;
371 	return ih;
372 }
373 
374 
375 int
376 intr_release(void *arg)
377 {
378 	irqhandler_t *ih = (irqhandler_t *)arg;
379 
380 	if (irq_release(ih->ih_num, ih) == 0) {
381 		free(ih, M_DEVBUF);
382 		return 0 ;
383 	}
384 	return 1;
385 }
386 
387 #if 0
388 u_int
389 disable_interrupts(u_int mask)
390 {
391 	u_int cpsr;
392 
393 	cpsr = SetCPSR(mask, mask);
394 	return cpsr;
395 }
396 
397 
398 u_int
399 restore_interrupts(u_int old_cpsr)
400 {
401 	int mask = I32_bit | F32_bit;
402 
403 	return SetCPSR(mask, old_cpsr & mask);
404 }
405 
406 
407 u_int
408 enable_interrupts(u_int mask)
409 {
410 
411 	return SetCPSR(mask, 0);
412 }
413 #endif
414 
415 /*
416  * void disable_irq(int irq)
417  *
418  * Disables a specific irq. The irq is removed from the master irq mask
419  */
420 
421 void
422 disable_irq(int irq)
423 {
424 	u_int oldirqstate;
425 
426 	oldirqstate = disable_interrupts(I32_bit);
427 	current_mask &= ~(1 << irq);
428 	irq_setmasks();
429 	restore_interrupts(oldirqstate);
430 }
431 
432 
433 /*
434  * void enable_irq(int irq)
435  *
436  * Enables a specific irq. The irq is added to the master irq mask
437  * This routine should be used with caution. A handler should already
438  * be installed.
439  */
440 
441 void
442 enable_irq(int irq)
443 {
444 	u_int oldirqstate;
445 
446 	oldirqstate = disable_interrupts(I32_bit);
447 	current_mask |= (1 << irq);
448 	irq_setmasks();
449 	restore_interrupts(oldirqstate);
450 }
451 
452 
453 /*
454  * void stray_irqhandler(u_int mask)
455  *
456  * Handler for stray interrupts. This gets called if a handler cannot be
457  * found for an interrupt.
458  */
459 
460 void
461 stray_irqhandler(u_int mask)
462 {
463 	static u_int stray_irqs = 0;
464 
465 	if (++stray_irqs <= 8)
466 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
467 		    stray_irqs >= 8 ? ": stopped logging" : "");
468 }
469