xref: /netbsd-src/sys/arch/arm/pic/pic.c (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /*	$NetBSD: pic.c,v 1.42 2018/04/01 04:35:04 ryo Exp $	*/
2 /*-
3  * Copyright (c) 2008 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Matt Thomas.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #define _INTR_PRIVATE
32 #include "opt_ddb.h"
33 #include "opt_multiprocessor.h"
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: pic.c,v 1.42 2018/04/01 04:35:04 ryo Exp $");
37 
38 #include <sys/param.h>
39 #include <sys/atomic.h>
40 #include <sys/cpu.h>
41 #include <sys/evcnt.h>
42 #include <sys/intr.h>
43 #include <sys/kernel.h>
44 #include <sys/kmem.h>
45 #include <sys/mutex.h>
46 #include <sys/once.h>
47 #include <sys/xcall.h>
48 #include <sys/ipi.h>
49 
50 #include <arm/armreg.h>
51 #include <arm/cpufunc.h>
52 #include <arm/locore.h>	/* for compat aarch64 */
53 
54 #ifdef DDB
55 #include <arm/db_machdep.h>
56 #endif
57 
58 #include <arm/pic/picvar.h>
59 
60 #if defined(__HAVE_PIC_PENDING_INTRS)
61 /*
62  * This implementation of pending interrupts on a MULTIPROCESSOR system makes
63  * the assumption that a PIC (pic_softc) shall only have all its interrupts
64  * come from the same CPU.  In other words, interrupts from a single PIC will
65  * not be distributed among multiple CPUs.
66  */
67 struct pic_pending {
68 	volatile uint32_t blocked_pics;
69 	volatile uint32_t pending_pics;
70 	volatile uint32_t pending_ipls;
71 };
72 static uint32_t
73 	pic_find_pending_irqs_by_ipl(struct pic_softc *, size_t, uint32_t, int);
74 static struct pic_softc *
75 	pic_list_find_pic_by_pending_ipl(struct pic_pending *, uint32_t);
76 static void
77 	pic_deliver_irqs(struct pic_pending *, struct pic_softc *, int, void *);
78 static void
79 	pic_list_deliver_irqs(struct pic_pending *, register_t, int, void *);
80 
81 #ifdef MULTIPROCESSOR
82 percpu_t *pic_pending_percpu;
83 #else
84 struct pic_pending pic_pending;
85 #endif /* MULTIPROCESSOR */
86 #endif /* __HAVE_PIC_PENDING_INTRS */
87 
88 struct pic_softc *pic_list[PIC_MAXPICS];
89 #if PIC_MAXPICS > 32
90 #error PIC_MAXPICS > 32 not supported
91 #endif
92 struct intrsource *pic_sources[PIC_MAXMAXSOURCES];
93 struct intrsource *pic__iplsources[PIC_MAXMAXSOURCES];
94 struct intrsource **pic_iplsource[NIPL] = {
95 	[0 ... NIPL-1] = pic__iplsources,
96 };
97 size_t pic_ipl_offset[NIPL+1];
98 
99 static kmutex_t pic_lock;
100 size_t pic_sourcebase;
101 static struct evcnt pic_deferral_ev =
102     EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "deferred", "intr");
103 EVCNT_ATTACH_STATIC(pic_deferral_ev);
104 
105 static int pic_init(void);
106 
107 #ifdef __HAVE_PIC_SET_PRIORITY
108 void
109 pic_set_priority(struct cpu_info *ci, int newipl)
110 {
111 	register_t psw = cpsid(I32_bit);
112 	if (pic_list[0] != NULL)
113 		(pic_list[0]->pic_ops->pic_set_priority)(pic_list[0], newipl);
114 	ci->ci_cpl = newipl;
115 	if ((psw & I32_bit) == 0)
116 		cpsie(I32_bit);
117 }
118 #endif
119 
120 #ifdef MULTIPROCESSOR
121 int
122 pic_ipi_ast(void *arg)
123 {
124 	setsoftast(curcpu());
125 	return 1;
126 }
127 
128 int
129 pic_ipi_nop(void *arg)
130 {
131 	/* do nothing */
132 	return 1;
133 }
134 
135 int
136 pic_ipi_xcall(void *arg)
137 {
138 	xc_ipi_handler();
139 	return 1;
140 }
141 
142 int
143 pic_ipi_generic(void *arg)
144 {
145 	ipi_cpu_handler();
146 	return 1;
147 }
148 
149 #ifdef DDB
150 int
151 pic_ipi_ddb(void *arg)
152 {
153 //	printf("%s: %s: tf=%p\n", __func__, curcpu()->ci_cpuname, arg);
154 	kdb_trap(-1, arg);
155 	return 1;
156 }
157 #endif /* DDB */
158 
159 #ifdef __HAVE_PREEMPTION
160 int
161 pic_ipi_kpreempt(void *arg)
162 {
163 	atomic_or_uint(&curcpu()->ci_astpending, __BIT(1));
164 	return 1;
165 }
166 #endif /* __HAVE_PREEMPTION */
167 
168 void
169 intr_cpu_init(struct cpu_info *ci)
170 {
171 	for (size_t slot = 0; slot < PIC_MAXPICS; slot++) {
172 		struct pic_softc * const pic = pic_list[slot];
173 		if (pic != NULL && pic->pic_ops->pic_cpu_init != NULL) {
174 			(*pic->pic_ops->pic_cpu_init)(pic, ci);
175 		}
176 	}
177 }
178 
179 typedef void (*pic_ipi_send_func_t)(struct pic_softc *, u_long);
180 
181 void
182 intr_ipi_send(const kcpuset_t *kcp, u_long ipi)
183 {
184 	struct cpu_info * const ci = curcpu();
185 	KASSERT(ipi < NIPI);
186 	bool __diagused sent_p = false;
187 	for (size_t slot = 0; slot < PIC_MAXPICS; slot++) {
188 		struct pic_softc * const pic = pic_list[slot];
189 		if (pic == NULL || pic->pic_cpus == NULL)
190 			continue;
191 		if (kcp == NULL || kcpuset_intersecting_p(kcp, pic->pic_cpus)) {
192 			// never send to ourself
193 			if (pic->pic_cpus == ci->ci_kcpuset)
194 				continue;
195 
196 			(*pic->pic_ops->pic_ipi_send)(pic, kcp, ipi);
197 			// If we were targeting a single CPU or this pic
198 			// handles all cpus, we're done.
199 			if (kcp != NULL || pic->pic_cpus == kcpuset_running)
200 				return;
201 			sent_p = true;
202 		}
203 	}
204 	KASSERT(cold || sent_p || arm_cpu_max == 1);
205 }
206 #endif /* MULTIPROCESSOR */
207 
208 #ifdef __HAVE_PIC_FAST_SOFTINTS
209 int
210 pic_handle_softint(void *arg)
211 {
212 	void softint_switch(lwp_t *, int);
213 	struct cpu_info * const ci = curcpu();
214 	const size_t softint = (size_t) arg;
215 	int s = splhigh();
216 	ci->ci_intr_depth--;	// don't count these as interrupts
217 	softint_switch(ci->ci_softlwps[softint], s);
218 	ci->ci_intr_depth++;
219 	splx(s);
220 	return 1;
221 }
222 #endif
223 
224 int
225 pic_handle_intr(void *arg)
226 {
227 	struct pic_softc * const pic = arg;
228 	int rv;
229 
230 	rv = (*pic->pic_ops->pic_find_pending_irqs)(pic);
231 
232 	return rv > 0;
233 }
234 
235 #if defined(__HAVE_PIC_PENDING_INTRS)
236 void
237 pic_mark_pending_source(struct pic_softc *pic, struct intrsource *is)
238 {
239 	const uint32_t ipl_mask = __BIT(is->is_ipl);
240 
241 	atomic_or_32(&pic->pic_pending_irqs[is->is_irq >> 5],
242 	    __BIT(is->is_irq & 0x1f));
243 
244 	atomic_or_32(&pic->pic_pending_ipls, ipl_mask);
245 #ifdef MULTIPROCESSOR
246 	struct pic_pending *pend = percpu_getref(pic_pending_percpu);
247 #else
248 	struct pic_pending *pend = &pic_pending;
249 #endif
250 	atomic_or_32(&pend->pending_ipls, ipl_mask);
251 	atomic_or_32(&pend->pending_pics, __BIT(pic->pic_id));
252 #ifdef MULTIPROCESSOR
253 	percpu_putref(pic_pending_percpu);
254 #endif
255 }
256 
257 void
258 pic_mark_pending(struct pic_softc *pic, int irq)
259 {
260 	struct intrsource * const is = pic->pic_sources[irq];
261 
262 	KASSERT(irq < pic->pic_maxsources);
263 	KASSERT(is != NULL);
264 
265 	pic_mark_pending_source(pic, is);
266 }
267 
268 uint32_t
269 pic_mark_pending_sources(struct pic_softc *pic, size_t irq_base,
270 	uint32_t pending)
271 {
272 	struct intrsource ** const isbase = &pic->pic_sources[irq_base];
273 	struct intrsource *is;
274 	volatile uint32_t *ipending = &pic->pic_pending_irqs[irq_base >> 5];
275 	uint32_t ipl_mask = 0;
276 
277 	if (pending == 0)
278 		return ipl_mask;
279 
280 	KASSERT((irq_base & 31) == 0);
281 
282 	(*pic->pic_ops->pic_block_irqs)(pic, irq_base, pending);
283 
284 	atomic_or_32(ipending, pending);
285 	while (pending != 0) {
286 		int n = ffs(pending);
287 		if (n-- == 0)
288 			break;
289 		is = isbase[n];
290 		KASSERT(is != NULL);
291 		KASSERT(irq_base <= is->is_irq && is->is_irq < irq_base + 32);
292 		pending &= ~__BIT(n);
293 		ipl_mask |= __BIT(is->is_ipl);
294 	}
295 
296 	atomic_or_32(&pic->pic_pending_ipls, ipl_mask);
297 #ifdef MULTIPROCESSOR
298 	struct pic_pending *pend = percpu_getref(pic_pending_percpu);
299 #else
300 	struct pic_pending *pend = &pic_pending;
301 #endif
302 	atomic_or_32(&pend->pending_ipls, ipl_mask);
303 	atomic_or_32(&pend->pending_pics, __BIT(pic->pic_id));
304 #ifdef MULTIPROCESSOR
305 	percpu_putref(pic_pending_percpu);
306 #endif
307 	return ipl_mask;
308 }
309 
310 uint32_t
311 pic_find_pending_irqs_by_ipl(struct pic_softc *pic, size_t irq_base,
312 	uint32_t pending, int ipl)
313 {
314 	uint32_t ipl_irq_mask = 0;
315 	uint32_t irq_mask;
316 
317 	for (;;) {
318 		int irq = ffs(pending);
319 		if (irq-- == 0)
320 			return ipl_irq_mask;
321 
322 		irq_mask = __BIT(irq);
323 #if 1
324     		KASSERTMSG(pic->pic_sources[irq_base + irq] != NULL,
325 		   "%s: irq_base %zu irq %d\n", __func__, irq_base, irq);
326 #else
327 		if (pic->pic_sources[irq_base + irq] == NULL) {
328 			aprint_error("stray interrupt? irq_base=%zu irq=%d\n",
329 			    irq_base, irq);
330 		} else
331 #endif
332 		if (pic->pic_sources[irq_base + irq]->is_ipl == ipl)
333 			ipl_irq_mask |= irq_mask;
334 
335 		pending &= ~irq_mask;
336 	}
337 }
338 #endif /* __HAVE_PIC_PENDING_INTRS */
339 
340 void
341 pic_dispatch(struct intrsource *is, void *frame)
342 {
343 	int (*func)(void *) = is->is_func;
344 	void *arg = is->is_arg;
345 
346 	if (__predict_false(arg == NULL)) {
347 		if (__predict_false(frame == NULL)) {
348 			pic_deferral_ev.ev_count++;
349 			return;
350 		}
351 		arg = frame;
352 	}
353 
354 #ifdef MULTIPROCESSOR
355 	if (!is->is_mpsafe) {
356 		KERNEL_LOCK(1, NULL);
357 		const u_int ci_blcnt __diagused = curcpu()->ci_biglock_count;
358 		const u_int l_blcnt __diagused = curlwp->l_blcnt;
359 		(void)(*func)(arg);
360 		KASSERT(ci_blcnt == curcpu()->ci_biglock_count);
361 		KASSERT(l_blcnt == curlwp->l_blcnt);
362 		KERNEL_UNLOCK_ONE(NULL);
363 	} else
364 #endif
365 		(void)(*func)(arg);
366 
367 
368 	struct pic_percpu * const pcpu = percpu_getref(is->is_pic->pic_percpu);
369 	KASSERT(pcpu->pcpu_magic == PICPERCPU_MAGIC);
370 	pcpu->pcpu_evs[is->is_irq].ev_count++;
371 	percpu_putref(is->is_pic->pic_percpu);
372 }
373 
374 #if defined(__HAVE_PIC_PENDING_INTRS)
375 void
376 pic_deliver_irqs(struct pic_pending *pend, struct pic_softc *pic, int ipl,
377     void *frame)
378 {
379 	const uint32_t ipl_mask = __BIT(ipl);
380 	struct intrsource *is;
381 	volatile uint32_t *ipending = pic->pic_pending_irqs;
382 	volatile uint32_t *iblocked = pic->pic_blocked_irqs;
383 	size_t irq_base;
384 #if PIC_MAXSOURCES > 32
385 	size_t irq_count;
386 	int poi = 0;		/* Possibility of interrupting */
387 #endif
388 	uint32_t pending_irqs;
389 	uint32_t blocked_irqs;
390 	int irq;
391 	bool progress __diagused = false;
392 
393 	KASSERT(pic->pic_pending_ipls & ipl_mask);
394 
395 	irq_base = 0;
396 #if PIC_MAXSOURCES > 32
397 	irq_count = 0;
398 #endif
399 
400 	for (;;) {
401 		pending_irqs = pic_find_pending_irqs_by_ipl(pic, irq_base,
402 		    *ipending, ipl);
403 		KASSERT((pending_irqs & *ipending) == pending_irqs);
404 		KASSERT((pending_irqs & ~(*ipending)) == 0);
405 		if (pending_irqs == 0) {
406 #if PIC_MAXSOURCES > 32
407 			irq_count += 32;
408 			if (__predict_true(irq_count >= pic->pic_maxsources)) {
409 				if (!poi)
410 					/*Interrupt at this level was handled.*/
411 					break;
412 				irq_base = 0;
413 				irq_count = 0;
414 				poi = 0;
415 				ipending = pic->pic_pending_irqs;
416 				iblocked = pic->pic_blocked_irqs;
417 			} else {
418 				irq_base += 32;
419 				ipending++;
420 				iblocked++;
421 				KASSERT(irq_base <= pic->pic_maxsources);
422 			}
423 			continue;
424 #else
425 			break;
426 #endif
427 		}
428 		progress = true;
429 		blocked_irqs = 0;
430 		do {
431 			irq = ffs(pending_irqs) - 1;
432 			KASSERT(irq >= 0);
433 
434 			atomic_and_32(ipending, ~__BIT(irq));
435 			is = pic->pic_sources[irq_base + irq];
436 			if (is != NULL) {
437 				cpsie(I32_bit);
438 				pic_dispatch(is, frame);
439 				cpsid(I32_bit);
440 #if PIC_MAXSOURCES > 32
441 				/*
442 				 * There is a possibility of interrupting
443 				 * from cpsie() to cpsid().
444 				 */
445 				poi = 1;
446 #endif
447 				blocked_irqs |= __BIT(irq);
448 			} else {
449 				KASSERT(0);
450 			}
451 			pending_irqs = pic_find_pending_irqs_by_ipl(pic,
452 			    irq_base, *ipending, ipl);
453 		} while (pending_irqs);
454 		if (blocked_irqs) {
455 			atomic_or_32(iblocked, blocked_irqs);
456 			atomic_or_32(&pend->blocked_pics, __BIT(pic->pic_id));
457 		}
458 	}
459 
460 	KASSERT(progress);
461 	/*
462 	 * Since interrupts are disabled, we don't have to be too careful
463 	 * about these.
464 	 */
465 	if (atomic_and_32_nv(&pic->pic_pending_ipls, ~ipl_mask) == 0)
466 		atomic_and_32(&pend->pending_pics, ~__BIT(pic->pic_id));
467 }
468 
469 static void
470 pic_list_unblock_irqs(struct pic_pending *pend)
471 {
472 	uint32_t blocked_pics = pend->blocked_pics;
473 
474 	pend->blocked_pics = 0;
475 
476 	for (;;) {
477 		struct pic_softc *pic;
478 #if PIC_MAXSOURCES > 32
479 		volatile uint32_t *iblocked;
480 		uint32_t blocked;
481 		size_t irq_base;
482 #endif
483 
484 		int pic_id = ffs(blocked_pics);
485 		if (pic_id-- == 0)
486 			return;
487 
488 		pic = pic_list[pic_id];
489 		KASSERT(pic != NULL);
490 #if PIC_MAXSOURCES > 32
491 		for (irq_base = 0, iblocked = pic->pic_blocked_irqs;
492 		     irq_base < pic->pic_maxsources;
493 		     irq_base += 32, iblocked++) {
494 			if ((blocked = *iblocked) != 0) {
495 				(*pic->pic_ops->pic_unblock_irqs)(pic,
496 				    irq_base, blocked);
497 				atomic_and_32(iblocked, ~blocked);
498 			}
499 		}
500 #else
501 		KASSERT(pic->pic_blocked_irqs[0] != 0);
502 		(*pic->pic_ops->pic_unblock_irqs)(pic,
503 		    0, pic->pic_blocked_irqs[0]);
504 		pic->pic_blocked_irqs[0] = 0;
505 #endif
506 		blocked_pics &= ~__BIT(pic_id);
507 	}
508 }
509 
510 
511 struct pic_softc *
512 pic_list_find_pic_by_pending_ipl(struct pic_pending *pend, uint32_t ipl_mask)
513 {
514 	uint32_t pending_pics = pend->pending_pics;
515 	struct pic_softc *pic;
516 
517 	for (;;) {
518 		int pic_id = ffs(pending_pics);
519 		if (pic_id-- == 0)
520 			return NULL;
521 
522 		pic = pic_list[pic_id];
523 		KASSERT(pic != NULL);
524 		if (pic->pic_pending_ipls & ipl_mask)
525 			return pic;
526 		pending_pics &= ~__BIT(pic_id);
527 	}
528 }
529 
530 void
531 pic_list_deliver_irqs(struct pic_pending *pend, register_t psw, int ipl,
532     void *frame)
533 {
534 	const uint32_t ipl_mask = __BIT(ipl);
535 	struct pic_softc *pic;
536 
537 	while ((pic = pic_list_find_pic_by_pending_ipl(pend, ipl_mask)) != NULL) {
538 		pic_deliver_irqs(pend, pic, ipl, frame);
539 		KASSERT((pic->pic_pending_ipls & ipl_mask) == 0);
540 	}
541 	atomic_and_32(&pend->pending_ipls, ~ipl_mask);
542 }
543 #endif /* __HAVE_PIC_PENDING_INTRS */
544 
545 void
546 pic_do_pending_ints(register_t psw, int newipl, void *frame)
547 {
548 	struct cpu_info * const ci = curcpu();
549 	if (__predict_false(newipl == IPL_HIGH)) {
550 		KASSERTMSG(ci->ci_cpl == IPL_HIGH, "cpl %d", ci->ci_cpl);
551 		return;
552 	}
553 #if defined(__HAVE_PIC_PENDING_INTRS)
554 #ifdef MULTIPROCESSOR
555 	struct pic_pending *pend = percpu_getref(pic_pending_percpu);
556 #else
557 	struct pic_pending *pend = &pic_pending;
558 #endif
559 	while ((pend->pending_ipls & ~__BIT(newipl)) > __BIT(newipl)) {
560 		KASSERT(pend->pending_ipls < __BIT(NIPL));
561 		for (;;) {
562 			int ipl = 31 - __builtin_clz(pend->pending_ipls);
563 			KASSERT(ipl < NIPL);
564 			if (ipl <= newipl)
565 				break;
566 
567 			pic_set_priority(ci, ipl);
568 			pic_list_deliver_irqs(pend, psw, ipl, frame);
569 			pic_list_unblock_irqs(pend);
570 		}
571 	}
572 #ifdef MULTIPROCESSOR
573 	percpu_putref(pic_pending_percpu);
574 #endif
575 #endif /* __HAVE_PIC_PENDING_INTRS */
576 #ifdef __HAVE_PREEMPTION
577 	if (newipl == IPL_NONE && (ci->ci_astpending & __BIT(1))) {
578 		pic_set_priority(ci, IPL_SCHED);
579 		kpreempt(0);
580 	}
581 #endif
582 	if (ci->ci_cpl != newipl)
583 		pic_set_priority(ci, newipl);
584 }
585 
586 static void
587 pic_percpu_allocate(void *v0, void *v1, struct cpu_info *ci)
588 {
589 	struct pic_percpu * const pcpu = v0;
590 	struct pic_softc * const pic = v1;
591 
592 	pcpu->pcpu_evs = kmem_zalloc(pic->pic_maxsources * sizeof(pcpu->pcpu_evs[0]),
593 	    KM_SLEEP);
594 	KASSERT(pcpu->pcpu_evs != NULL);
595 
596 #define	PCPU_NAMELEN	32
597 #ifdef DIAGNOSTIC
598 	const size_t namelen = strlen(pic->pic_name) + 4 + strlen(ci->ci_data.cpu_name);
599 #endif
600 
601 	KASSERT(namelen < PCPU_NAMELEN);
602 	pcpu->pcpu_name = kmem_alloc(PCPU_NAMELEN, KM_SLEEP);
603 #ifdef MULTIPROCESSOR
604 	snprintf(pcpu->pcpu_name, PCPU_NAMELEN,
605 	    "%s (%s)", pic->pic_name, ci->ci_data.cpu_name);
606 #else
607 	strlcpy(pcpu->pcpu_name, pic->pic_name, PCPU_NAMELEN);
608 #endif
609 	pcpu->pcpu_magic = PICPERCPU_MAGIC;
610 #if 0
611 	printf("%s: %s %s: <%s>\n",
612 	    __func__, ci->ci_data.cpu_name, pic->pic_name,
613 	    pcpu->pcpu_name);
614 #endif
615 }
616 
617 #if defined(__HAVE_PIC_PENDING_INTRS) && defined(MULTIPROCESSOR)
618 static void
619 pic_pending_zero(void *v0, void *v1, struct cpu_info *ci)
620 {
621 	struct pic_pending * const p = v0;
622 	memset(p, 0, sizeof(*p));
623 }
624 #endif /* __HAVE_PIC_PENDING_INTRS && MULTIPROCESSOR */
625 
626 static int
627 pic_init(void)
628 {
629 
630 	mutex_init(&pic_lock, MUTEX_DEFAULT, IPL_HIGH);
631 
632 	return 0;
633 }
634 
635 void
636 pic_add(struct pic_softc *pic, int irqbase)
637 {
638 	int slot, maybe_slot = -1;
639 	size_t sourcebase;
640 	static ONCE_DECL(pic_once);
641 
642 	RUN_ONCE(&pic_once, pic_init);
643 
644 	KASSERT(strlen(pic->pic_name) > 0);
645 
646 #if defined(__HAVE_PIC_PENDING_INTRS) && defined(MULTIPROCESSOR)
647 	if (__predict_false(pic_pending_percpu == NULL)) {
648 		pic_pending_percpu = percpu_alloc(sizeof(struct pic_pending));
649 
650 		/*
651 		 * Now zero the per-cpu pending data.
652 		 */
653 		percpu_foreach(pic_pending_percpu, pic_pending_zero, NULL);
654 	}
655 #endif /* __HAVE_PIC_PENDING_INTRS && MULTIPROCESSOR */
656 
657 	mutex_enter(&pic_lock);
658 	for (slot = 0; slot < PIC_MAXPICS; slot++) {
659 		struct pic_softc * const xpic = pic_list[slot];
660 		if (xpic == NULL) {
661 			if (maybe_slot < 0)
662 				maybe_slot = slot;
663 			if (irqbase < 0)
664 				break;
665 			continue;
666 		}
667 		if (irqbase < 0 || xpic->pic_irqbase < 0)
668 			continue;
669 		if (irqbase >= xpic->pic_irqbase + xpic->pic_maxsources)
670 			continue;
671 		if (irqbase + pic->pic_maxsources <= xpic->pic_irqbase)
672 			continue;
673 		panic("pic_add: pic %s (%zu sources @ irq %u) conflicts"
674 		    " with pic %s (%zu sources @ irq %u)",
675 		    pic->pic_name, pic->pic_maxsources, irqbase,
676 		    xpic->pic_name, xpic->pic_maxsources, xpic->pic_irqbase);
677 	}
678 	slot = maybe_slot;
679 #if 0
680 	printf("%s: pic_sourcebase=%zu pic_maxsources=%zu\n",
681 	    pic->pic_name, pic_sourcebase, pic->pic_maxsources);
682 #endif
683 	KASSERTMSG(pic->pic_maxsources <= PIC_MAXSOURCES, "%zu",
684 	    pic->pic_maxsources);
685 	KASSERT(pic_sourcebase + pic->pic_maxsources <= PIC_MAXMAXSOURCES);
686 	sourcebase = pic_sourcebase;
687 	pic_sourcebase += pic->pic_maxsources;
688 
689 	mutex_exit(&pic_lock);
690 
691 	/*
692 	 * Allocate a pointer to each cpu's evcnts and then, for each cpu,
693 	 * allocate its evcnts and then attach an evcnt for each pin.
694 	 * We can't allocate the evcnt structures directly since
695 	 * percpu will move the contents of percpu memory around and
696 	 * corrupt the pointers in the evcnts themselves.  Remember, any
697 	 * problem can be solved with sufficient indirection.
698 	 */
699 	pic->pic_percpu = percpu_alloc(sizeof(struct pic_percpu));
700 
701 	/*
702 	 * Now allocate the per-cpu evcnts.
703 	 */
704 	percpu_foreach(pic->pic_percpu, pic_percpu_allocate, pic);
705 
706 	pic->pic_sources = &pic_sources[sourcebase];
707 	pic->pic_irqbase = irqbase;
708 	pic->pic_id = slot;
709 #ifdef __HAVE_PIC_SET_PRIORITY
710 	KASSERT((slot == 0) == (pic->pic_ops->pic_set_priority != NULL));
711 #endif
712 #ifdef MULTIPROCESSOR
713 	KASSERT((pic->pic_cpus != NULL) == (pic->pic_ops->pic_ipi_send != NULL));
714 #endif
715 	pic_list[slot] = pic;
716 }
717 
718 int
719 pic_alloc_irq(struct pic_softc *pic)
720 {
721 	int irq;
722 
723 	for (irq = 0; irq < pic->pic_maxsources; irq++) {
724 		if (pic->pic_sources[irq] == NULL)
725 			return irq;
726 	}
727 
728 	return -1;
729 }
730 
731 static void
732 pic_percpu_evcnt_attach(void *v0, void *v1, struct cpu_info *ci)
733 {
734 	struct pic_percpu * const pcpu = v0;
735 	struct intrsource * const is = v1;
736 
737 	KASSERT(pcpu->pcpu_magic == PICPERCPU_MAGIC);
738 	evcnt_attach_dynamic(&pcpu->pcpu_evs[is->is_irq], EVCNT_TYPE_INTR, NULL,
739 	    pcpu->pcpu_name, is->is_source);
740 }
741 
742 void *
743 pic_establish_intr(struct pic_softc *pic, int irq, int ipl, int type,
744 	int (*func)(void *), void *arg)
745 {
746 	struct intrsource *is;
747 	int off, nipl;
748 
749 	if (pic->pic_sources[irq]) {
750 		printf("pic_establish_intr: pic %s irq %d already present\n",
751 		    pic->pic_name, irq);
752 		return NULL;
753 	}
754 
755 	is = kmem_zalloc(sizeof(*is), KM_SLEEP);
756 	is->is_pic = pic;
757 	is->is_irq = irq;
758 	is->is_ipl = ipl;
759 	is->is_type = type & 0xff;
760 	is->is_func = func;
761 	is->is_arg = arg;
762 #ifdef MULTIPROCESSOR
763 	is->is_mpsafe = (type & IST_MPSAFE) || ipl != IPL_VM;
764 #endif
765 
766 	if (pic->pic_ops->pic_source_name)
767 		(*pic->pic_ops->pic_source_name)(pic, irq, is->is_source,
768 		    sizeof(is->is_source));
769 	else
770 		snprintf(is->is_source, sizeof(is->is_source), "irq %d", irq);
771 
772 	/*
773 	 * Now attach the per-cpu evcnts.
774 	 */
775 	percpu_foreach(pic->pic_percpu, pic_percpu_evcnt_attach, is);
776 
777 	pic->pic_sources[irq] = is;
778 
779 	/*
780 	 * First try to use an existing slot which is empty.
781 	 */
782 	for (off = pic_ipl_offset[ipl]; off < pic_ipl_offset[ipl+1]; off++) {
783 		if (pic__iplsources[off] == NULL) {
784 			is->is_iplidx = off - pic_ipl_offset[ipl];
785 			pic__iplsources[off] = is;
786 			goto unblock;
787 		}
788 	}
789 
790 	/*
791 	 * Move up all the sources by one.
792  	 */
793 	if (ipl < NIPL) {
794 		off = pic_ipl_offset[ipl+1];
795 		memmove(&pic__iplsources[off+1], &pic__iplsources[off],
796 		    sizeof(pic__iplsources[0]) * (pic_ipl_offset[NIPL] - off));
797 	}
798 
799 	/*
800 	 * Advance the offset of all IPLs higher than this.  Include an
801 	 * extra one as well.  Thus the number of sources per ipl is
802 	 * pic_ipl_offset[ipl+1] - pic_ipl_offset[ipl].
803 	 */
804 	for (nipl = ipl + 1; nipl <= NIPL; nipl++)
805 		pic_ipl_offset[nipl]++;
806 
807 	/*
808 	 * Insert into the previously made position at the end of this IPL's
809 	 * sources.
810 	 */
811 	off = pic_ipl_offset[ipl + 1] - 1;
812 	is->is_iplidx = off - pic_ipl_offset[ipl];
813 	pic__iplsources[off] = is;
814 
815 	(*pic->pic_ops->pic_establish_irq)(pic, is);
816 
817 unblock:
818 	(*pic->pic_ops->pic_unblock_irqs)(pic, is->is_irq & ~0x1f,
819 	    __BIT(is->is_irq & 0x1f));
820 
821 	/* We're done. */
822 	return is;
823 }
824 
825 static void
826 pic_percpu_evcnt_deattach(void *v0, void *v1, struct cpu_info *ci)
827 {
828 	struct pic_percpu * const pcpu = v0;
829 	struct intrsource * const is = v1;
830 
831 	KASSERT(pcpu->pcpu_magic == PICPERCPU_MAGIC);
832 	evcnt_detach(&pcpu->pcpu_evs[is->is_irq]);
833 }
834 
835 void
836 pic_disestablish_source(struct intrsource *is)
837 {
838 	struct pic_softc * const pic = is->is_pic;
839 	const int irq = is->is_irq;
840 
841 	KASSERT(is == pic->pic_sources[irq]);
842 
843 	(*pic->pic_ops->pic_block_irqs)(pic, irq & ~0x1f, __BIT(irq & 0x1f));
844 	pic->pic_sources[irq] = NULL;
845 	pic__iplsources[pic_ipl_offset[is->is_ipl] + is->is_iplidx] = NULL;
846 	/*
847 	 * Now detach the per-cpu evcnts.
848 	 */
849 	percpu_foreach(pic->pic_percpu, pic_percpu_evcnt_deattach, is);
850 
851 	kmem_free(is, sizeof(*is));
852 }
853 
854 void *
855 intr_establish(int irq, int ipl, int type, int (*func)(void *), void *arg)
856 {
857 	KASSERT(!cpu_intr_p());
858 	KASSERT(!cpu_softintr_p());
859 
860 	for (size_t slot = 0; slot < PIC_MAXPICS; slot++) {
861 		struct pic_softc * const pic = pic_list[slot];
862 		if (pic == NULL || pic->pic_irqbase < 0)
863 			continue;
864 		if (pic->pic_irqbase <= irq
865 		    && irq < pic->pic_irqbase + pic->pic_maxsources) {
866 			return pic_establish_intr(pic, irq - pic->pic_irqbase,
867 			    ipl, type, func, arg);
868 		}
869 	}
870 
871 	return NULL;
872 }
873 
874 void
875 intr_disestablish(void *ih)
876 {
877 	struct intrsource * const is = ih;
878 
879 	KASSERT(!cpu_intr_p());
880 	KASSERT(!cpu_softintr_p());
881 
882 	pic_disestablish_source(is);
883 }
884