xref: /netbsd/sys/arch/evbarm/iq80310/iq80310_intr.c (revision c4a72b64)
1 /*	$NetBSD: iq80310_intr.c,v 1.18 2002/10/09 00:03:42 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
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  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed for the NetBSD Project by
20  *	Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #ifndef EVBARM_SPL_NOINLINE
39 #define	EVBARM_SPL_NOINLINE
40 #endif
41 
42 /*
43  * Interrupt support for the Intel IQ80310.
44  */
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/malloc.h>
49 
50 #include <uvm/uvm_extern.h>
51 
52 #include <machine/bus.h>
53 #include <machine/intr.h>
54 
55 #include <arm/cpufunc.h>
56 
57 #include <arm/xscale/i80200reg.h>
58 #include <arm/xscale/i80200var.h>
59 
60 #include <evbarm/iq80310/iq80310reg.h>
61 #include <evbarm/iq80310/iq80310var.h>
62 #include <evbarm/iq80310/obiovar.h>
63 
64 /* Interrupt handler queues. */
65 struct intrq intrq[NIRQ];
66 
67 /* Interrupts to mask at each level. */
68 int iq80310_imask[NIPL];
69 
70 /* Current interrupt priority level. */
71 __volatile int current_spl_level;
72 
73 /* Interrupts pending. */
74 __volatile int iq80310_ipending;
75 
76 /* Software copy of the IRQs we have enabled. */
77 uint32_t intr_enabled;
78 
79 /*
80  * Map a software interrupt queue index (at the top of the word, and
81  * highest priority softintr is encountered first in an ffs()).
82  */
83 #define	SI_TO_IRQBIT(si)	(1U << (31 - (si)))
84 
85 /*
86  * Map a software interrupt queue to an interrupt priority level.
87  */
88 static const int si_to_ipl[SI_NQUEUES] = {
89 	IPL_SOFT,		/* SI_SOFT */
90 	IPL_SOFTCLOCK,		/* SI_SOFTCLOCK */
91 	IPL_SOFTNET,		/* SI_SOFTNET */
92 	IPL_SOFTSERIAL,		/* SI_SOFTSERIAL */
93 };
94 
95 void	iq80310_intr_dispatch(struct clockframe *frame);
96 
97 static __inline uint32_t
98 iq80310_intstat_read(void)
99 {
100 	uint32_t intstat;
101 
102 	intstat = CPLD_READ(IQ80310_XINT3_STATUS) & 0x1f;
103 #if defined(IRQ_READ_XINT0)
104 	if (IRQ_READ_XINT0)
105 		intstat |= (CPLD_READ(IQ80310_XINT0_STATUS) & 0x7) << 5;
106 #endif
107 
108 	/* XXX Why do we have to mask off? */
109 	return (intstat & intr_enabled);
110 }
111 
112 static __inline void
113 iq80310_set_intrmask(void)
114 {
115 	uint32_t disabled;
116 
117 	intr_enabled |= IRQ_BITS_ALWAYS_ON;
118 
119 	/* The XINT_MASK register sets a bit to *disable*. */
120 	disabled = (~intr_enabled) & IRQ_BITS;
121 
122 	CPLD_WRITE(IQ80310_XINT_MASK, disabled & 0x1f);
123 }
124 
125 static __inline void
126 iq80310_enable_irq(int irq)
127 {
128 
129 	intr_enabled |= (1U << irq);
130 	iq80310_set_intrmask();
131 }
132 
133 static __inline void
134 iq80310_disable_irq(int irq)
135 {
136 
137 	intr_enabled &= ~(1U << irq);
138 	iq80310_set_intrmask();
139 }
140 
141 /*
142  * NOTE: This routine must be called with interrupts disabled in the CPSR.
143  */
144 static void
145 iq80310_intr_calculate_masks(void)
146 {
147 	struct intrq *iq;
148 	struct intrhand *ih;
149 	int irq, ipl;
150 
151 	/* First, figure out which IPLs each IRQ has. */
152 	for (irq = 0; irq < NIRQ; irq++) {
153 		int levels = 0;
154 		iq = &intrq[irq];
155 		iq80310_disable_irq(irq);
156 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
157 		     ih = TAILQ_NEXT(ih, ih_list))
158 			levels |= (1U << ih->ih_ipl);
159 		iq->iq_levels = levels;
160 	}
161 
162 	/* Next, figure out which IRQs are used by each IPL. */
163 	for (ipl = 0; ipl < NIPL; ipl++) {
164 		int irqs = 0;
165 		for (irq = 0; irq < NIRQ; irq++) {
166 			if (intrq[irq].iq_levels & (1U << ipl))
167 				irqs |= (1U << irq);
168 		}
169 		iq80310_imask[ipl] = irqs;
170 	}
171 
172 	iq80310_imask[IPL_NONE] = 0;
173 
174 	/*
175 	 * Initialize the soft interrupt masks to block themselves.
176 	 */
177 	iq80310_imask[IPL_SOFT] = SI_TO_IRQBIT(SI_SOFT);
178 	iq80310_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
179 	iq80310_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
180 	iq80310_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
181 
182 	/*
183 	 * splsoftclock() is the only interface that users of the
184 	 * generic software interrupt facility have to block their
185 	 * soft intrs, so splsoftclock() must also block IPL_SOFT.
186 	 */
187 	iq80310_imask[IPL_SOFTCLOCK] |= iq80310_imask[IPL_SOFT];
188 
189 	/*
190 	 * splsoftnet() must also block splsoftclock(), since we don't
191 	 * want timer-driven network events to occur while we're
192 	 * processing incoming packets.
193 	 */
194 	iq80310_imask[IPL_SOFTNET] |= iq80310_imask[IPL_SOFTCLOCK];
195 
196 	/*
197 	 * Enforce a heirarchy that gives "slow" device (or devices with
198 	 * limited input buffer space/"real-time" requirements) a better
199 	 * chance at not dropping data.
200 	 */
201 	iq80310_imask[IPL_BIO] |= iq80310_imask[IPL_SOFTNET];
202 	iq80310_imask[IPL_NET] |= iq80310_imask[IPL_BIO];
203 	iq80310_imask[IPL_SOFTSERIAL] |= iq80310_imask[IPL_NET];
204 	iq80310_imask[IPL_TTY] |= iq80310_imask[IPL_SOFTSERIAL];
205 
206 	/*
207 	 * splvm() blocks all interrupts that use the kernel memory
208 	 * allocation facilities.
209 	 */
210 	iq80310_imask[IPL_IMP] |= iq80310_imask[IPL_TTY];
211 
212 	/*
213 	 * Audio devices are not allowed to perform memory allocation
214 	 * in their interrupt routines, and they have fairly "real-time"
215 	 * requirements, so give them a high interrupt priority.
216 	 */
217 	iq80310_imask[IPL_AUDIO] |= iq80310_imask[IPL_IMP];
218 
219 	/*
220 	 * splclock() must block anything that uses the scheduler.
221 	 */
222 	iq80310_imask[IPL_CLOCK] |= iq80310_imask[IPL_AUDIO];
223 
224 	/*
225 	 * No separate statclock on the IQ80310.
226 	 */
227 	iq80310_imask[IPL_STATCLOCK] |= iq80310_imask[IPL_CLOCK];
228 
229 	/*
230 	 * splhigh() must block "everything".
231 	 */
232 	iq80310_imask[IPL_HIGH] |= iq80310_imask[IPL_STATCLOCK];
233 
234 	/*
235 	 * XXX We need serial drivers to run at the absolute highest priority
236 	 * in order to avoid overruns, so serial > high.
237 	 */
238 	iq80310_imask[IPL_SERIAL] |= iq80310_imask[IPL_HIGH];
239 
240 	/*
241 	 * Now compute which IRQs must be blocked when servicing any
242 	 * given IRQ.
243 	 */
244 	for (irq = 0; irq < NIRQ; irq++) {
245 		int irqs = (1U << irq);
246 		iq = &intrq[irq];
247 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
248 			iq80310_enable_irq(irq);
249 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
250 		     ih = TAILQ_NEXT(ih, ih_list))
251 			irqs |= iq80310_imask[ih->ih_ipl];
252 		iq->iq_mask = irqs;
253 	}
254 }
255 
256 void
257 iq80310_do_soft(void)
258 {
259 	static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
260 	int new, oldirqstate;
261 
262 	if (__cpu_simple_lock_try(&processing) == 0)
263 		return;
264 
265 	new = current_spl_level;
266 
267 	oldirqstate = disable_interrupts(I32_bit);
268 
269 #define	DO_SOFTINT(si)							\
270 	if ((iq80310_ipending & ~new) & SI_TO_IRQBIT(si)) {		\
271 		iq80310_ipending &= ~SI_TO_IRQBIT(si);			\
272 		current_spl_level |= iq80310_imask[si_to_ipl[(si)]];	\
273 		restore_interrupts(oldirqstate);			\
274 		softintr_dispatch(si);					\
275 		oldirqstate = disable_interrupts(I32_bit);		\
276 		current_spl_level = new;				\
277 	}
278 
279 	DO_SOFTINT(SI_SOFTSERIAL);
280 	DO_SOFTINT(SI_SOFTNET);
281 	DO_SOFTINT(SI_SOFTCLOCK);
282 	DO_SOFTINT(SI_SOFT);
283 
284 	__cpu_simple_unlock(&processing);
285 
286 	restore_interrupts(oldirqstate);
287 }
288 
289 int
290 _splraise(int ipl)
291 {
292 
293 	return (iq80310_splraise(ipl));
294 }
295 
296 __inline void
297 splx(int new)
298 {
299 
300 	return (iq80310_splx(new));
301 }
302 
303 int
304 _spllower(int ipl)
305 {
306 
307 	return (iq80310_spllower(ipl));
308 }
309 
310 void
311 _setsoftintr(int si)
312 {
313 	int oldirqstate;
314 
315 	oldirqstate = disable_interrupts(I32_bit);
316 	iq80310_ipending |= SI_TO_IRQBIT(si);
317 	restore_interrupts(oldirqstate);
318 
319 	/* Process unmasked pending soft interrupts. */
320 	if ((iq80310_ipending & ~IRQ_BITS) & ~current_spl_level)
321 		iq80310_do_soft();
322 }
323 
324 void
325 iq80310_intr_init(void)
326 {
327 	struct intrq *iq;
328 	int i;
329 
330 	/*
331 	 * The Secondary PCI interrupts INTA, INTB, and INTC
332 	 * area always enabled, since they cannot be masked
333 	 * in the CPLD.
334 	 */
335 	intr_enabled |= IRQ_BITS_ALWAYS_ON;
336 
337 	for (i = 0; i < NIRQ; i++) {
338 		iq = &intrq[i];
339 		TAILQ_INIT(&iq->iq_list);
340 
341 		sprintf(iq->iq_name, "irq %d", i);
342 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
343 		    NULL, "iq80310", iq->iq_name);
344 	}
345 
346 	iq80310_intr_calculate_masks();
347 
348 	/* Enable external interrupts on the i80200. */
349 	i80200_extirq_dispatch = iq80310_intr_dispatch;
350 	i80200_intr_enable(INTCTL_IM | INTCTL_PM);
351 
352 	/* Enable IRQs (don't yet use FIQs). */
353 	enable_interrupts(I32_bit);
354 }
355 
356 void *
357 iq80310_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
358 {
359 	struct intrq *iq;
360 	struct intrhand *ih;
361 	u_int oldirqstate;
362 
363 	if (irq < 0 || irq > NIRQ)
364 		panic("iq80310_intr_establish: IRQ %d out of range", irq);
365 
366 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
367 	if (ih == NULL)
368 		return (NULL);
369 
370 	ih->ih_func = func;
371 	ih->ih_arg = arg;
372 	ih->ih_ipl = ipl;
373 	ih->ih_irq = irq;
374 
375 	iq = &intrq[irq];
376 
377 	/* All IQ80310 interrupts are level-triggered. */
378 	iq->iq_ist = IST_LEVEL;
379 
380 	oldirqstate = disable_interrupts(I32_bit);
381 
382 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
383 
384 	iq80310_intr_calculate_masks();
385 
386 	restore_interrupts(oldirqstate);
387 
388 	return (ih);
389 }
390 
391 void
392 iq80310_intr_disestablish(void *cookie)
393 {
394 	struct intrhand *ih = cookie;
395 	struct intrq *iq = &intrq[ih->ih_irq];
396 	int oldirqstate;
397 
398 	oldirqstate = disable_interrupts(I32_bit);
399 
400 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
401 
402 	iq80310_intr_calculate_masks();
403 
404 	restore_interrupts(oldirqstate);
405 }
406 
407 void
408 iq80310_intr_dispatch(struct clockframe *frame)
409 {
410 	struct intrq *iq;
411 	struct intrhand *ih;
412 	int oldirqstate, pcpl, irq, ibit, hwpend, rv, stray;
413 
414 	stray = 1;
415 
416 	/* First, disable external IRQs. */
417 	i80200_intr_disable(INTCTL_IM | INTCTL_PM);
418 
419 	pcpl = current_spl_level;
420 
421 	for (hwpend = iq80310_intstat_read(); hwpend != 0;) {
422 		irq = ffs(hwpend) - 1;
423 		ibit = (1U << irq);
424 
425 		stray = 0;
426 
427 		hwpend &= ~ibit;
428 
429 		if (pcpl & ibit) {
430 			/*
431 			 * IRQ is masked; mark it as pending and check
432 			 * the next one.  Note: external IRQs are already
433 			 * disabled.
434 			 */
435 			iq80310_ipending |= ibit;
436 			continue;
437 		}
438 
439 		iq80310_ipending &= ~ibit;
440 		rv = 0;
441 
442 		iq = &intrq[irq];
443 		iq->iq_ev.ev_count++;
444 		uvmexp.intrs++;
445 		current_spl_level |= iq->iq_mask;
446 		oldirqstate = enable_interrupts(I32_bit);
447 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
448 		     ih = TAILQ_NEXT(ih, ih_list)) {
449 			rv |= (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
450 		}
451 		restore_interrupts(oldirqstate);
452 
453 		current_spl_level = pcpl;
454 
455 #if 0 /* XXX */
456 		if (rv == 0)
457 			printf("Stray interrupt: IRQ %d\n", irq);
458 #endif
459 	}
460 
461 #if 0 /* XXX */
462 	if (stray)
463 		printf("Stray external interrupt\n");
464 #endif
465 
466 	/* Check for pendings soft intrs. */
467 	if ((iq80310_ipending & ~IRQ_BITS) & ~current_spl_level) {
468 		oldirqstate = enable_interrupts(I32_bit);
469 		iq80310_do_soft();
470 		restore_interrupts(oldirqstate);
471 	}
472 
473 	/*
474 	 * If no hardware interrupts are masked, re-enable external
475 	 * interrupts.
476 	 */
477 	if ((iq80310_ipending & IRQ_BITS) == 0)
478 		i80200_intr_enable(INTCTL_IM | INTCTL_PM);
479 }
480