xref: /netbsd/sys/arch/evbarm/iq80310/iq80310_intr.c (revision bf9ec67e)
1 /*	$NetBSD: iq80310_intr.c,v 1.12 2002/04/14 21:32:24 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 /*
39  * Interrupt support for the Intel IQ80310.
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/malloc.h>
45 
46 #include <uvm/uvm_extern.h>
47 
48 #include <machine/bus.h>
49 #include <machine/intr.h>
50 
51 #include <arm/cpufunc.h>
52 
53 #include <arm/xscale/i80200reg.h>
54 #include <arm/xscale/i80200var.h>
55 
56 #include <evbarm/iq80310/iq80310reg.h>
57 #include <evbarm/iq80310/iq80310var.h>
58 #include <evbarm/iq80310/obiovar.h>
59 
60 #if defined(IOP310_TEAMASA_NPWR)
61 /*
62  * We have 5 interrupt source bits -- all in XINT3.  All interrupts
63  * can be masked in the CPLD.
64  */
65 #define	IRQ_BITS		0x1f
66 #define	IRQ_BITS_ALWAYS_ON	0x00
67 #else /* Default to stock IQ80310 */
68 /*
69  * We have 8 interrupt source bits -- 5 in the XINT3 register, and 3
70  * in the XINT0 register (the upper 3).  Note that the XINT0 IRQs
71  * (SPCI INTA, INTB, and INTC) are always enabled, since they can not
72  * be masked out in the CPLD (it provides only status, not masking,
73  * for those interrupts).
74  */
75 #define	IRQ_BITS		0xff
76 #define	IRQ_BITS_ALWAYS_ON	0xe0
77 #define	IRQ_READ_XINT0		1	/* XXX only if board rev >= F */
78 #endif /* list of IQ80310-based designs */
79 
80 /* Interrupt handler queues. */
81 struct intrq intrq[NIRQ];
82 
83 /* Interrupts to mask at each level. */
84 static int imask[NIPL];
85 
86 /* Current interrupt priority level. */
87 __volatile int current_spl_level;
88 
89 /* Interrupts pending. */
90 static __volatile int ipending;
91 
92 /* Software copy of the IRQs we have enabled. */
93 uint32_t intr_enabled;
94 
95 /*
96  * Map a software interrupt queue index (at the top of the word, and
97  * highest priority softintr is encountered first in an ffs()).
98  */
99 #define	SI_TO_IRQBIT(si)	(1U << (31 - (si)))
100 
101 /*
102  * Map a software interrupt queue to an interrupt priority level.
103  */
104 static const int si_to_ipl[SI_NQUEUES] = {
105 	IPL_SOFT,		/* SI_SOFT */
106 	IPL_SOFTCLOCK,		/* SI_SOFTCLOCK */
107 	IPL_SOFTNET,		/* SI_SOFTNET */
108 	IPL_SOFTSERIAL,		/* SI_SOFTSERIAL */
109 };
110 
111 void	iq80310_intr_dispatch(struct clockframe *frame);
112 
113 static __inline uint32_t
114 iq80310_intstat_read(void)
115 {
116 	uint32_t intstat;
117 
118 	intstat = CPLD_READ(IQ80310_XINT3_STATUS) & 0x1f;
119 #if defined(IRQ_READ_XINT0)
120 	if (IRQ_READ_XINT0)
121 		intstat |= (CPLD_READ(IQ80310_XINT0_STATUS) & 0x7) << 5;
122 #endif
123 
124 	/* XXX Why do we have to mask off? */
125 	return (intstat & intr_enabled);
126 }
127 
128 static __inline void
129 iq80310_set_intrmask(void)
130 {
131 	uint32_t disabled;
132 
133 	intr_enabled |= IRQ_BITS_ALWAYS_ON;
134 
135 	/* The XINT_MASK register sets a bit to *disable*. */
136 	disabled = (~intr_enabled) & IRQ_BITS;
137 
138 	CPLD_WRITE(IQ80310_XINT_MASK, disabled & 0x1f);
139 }
140 
141 static __inline void
142 iq80310_enable_irq(int irq)
143 {
144 
145 	intr_enabled |= (1U << irq);
146 	iq80310_set_intrmask();
147 }
148 
149 static __inline void
150 iq80310_disable_irq(int irq)
151 {
152 
153 	intr_enabled &= ~(1U << irq);
154 	iq80310_set_intrmask();
155 }
156 
157 /*
158  * NOTE: This routine must be called with interrupts disabled in the CPSR.
159  */
160 static void
161 iq80310_intr_calculate_masks(void)
162 {
163 	struct intrq *iq;
164 	struct intrhand *ih;
165 	int irq, ipl;
166 
167 	/* First, figure out which IPLs each IRQ has. */
168 	for (irq = 0; irq < NIRQ; irq++) {
169 		int levels = 0;
170 		iq = &intrq[irq];
171 		iq80310_disable_irq(irq);
172 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
173 		     ih = TAILQ_NEXT(ih, ih_list))
174 			levels |= (1U << ih->ih_ipl);
175 		iq->iq_levels = levels;
176 	}
177 
178 	/* Next, figure out which IRQs are used by each IPL. */
179 	for (ipl = 0; ipl < NIPL; ipl++) {
180 		int irqs = 0;
181 		for (irq = 0; irq < NIRQ; irq++) {
182 			if (intrq[irq].iq_levels & (1U << ipl))
183 				irqs |= (1U << irq);
184 		}
185 		imask[ipl] = irqs;
186 	}
187 
188 	imask[IPL_NONE] = 0;
189 
190 	/*
191 	 * Initialize the soft interrupt masks to block themselves.
192 	 */
193 	imask[IPL_SOFT] = SI_TO_IRQBIT(SI_SOFT);
194 	imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
195 	imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
196 	imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
197 
198 	/*
199 	 * splsoftclock() is the only interface that users of the
200 	 * generic software interrupt facility have to block their
201 	 * soft intrs, so splsoftclock() must also block IPL_SOFT.
202 	 */
203 	imask[IPL_SOFTCLOCK] |= imask[IPL_SOFT];
204 
205 	/*
206 	 * splsoftnet() must also block splsoftclock(), since we don't
207 	 * want timer-driven network events to occur while we're
208 	 * processing incoming packets.
209 	 */
210 	imask[IPL_SOFTNET] |= imask[IPL_SOFTCLOCK];
211 
212 	/*
213 	 * Enforce a heirarchy that gives "slow" device (or devices with
214 	 * limited input buffer space/"real-time" requirements) a better
215 	 * chance at not dropping data.
216 	 */
217 	imask[IPL_BIO] |= imask[IPL_SOFTNET];
218 	imask[IPL_NET] |= imask[IPL_BIO];
219 	imask[IPL_SOFTSERIAL] |= imask[IPL_NET];
220 	imask[IPL_TTY] |= imask[IPL_SOFTSERIAL];
221 
222 	/*
223 	 * splvm() blocks all interrupts that use the kernel memory
224 	 * allocation facilities.
225 	 */
226 	imask[IPL_IMP] |= imask[IPL_TTY];
227 
228 	/*
229 	 * Audio devices are not allowed to perform memory allocation
230 	 * in their interrupt routines, and they have fairly "real-time"
231 	 * requirements, so give them a high interrupt priority.
232 	 */
233 	imask[IPL_AUDIO] |= imask[IPL_IMP];
234 
235 	/*
236 	 * splclock() must block anything that uses the scheduler.
237 	 */
238 	imask[IPL_CLOCK] |= imask[IPL_AUDIO];
239 
240 	/*
241 	 * No separate statclock on the IQ80310.
242 	 */
243 	imask[IPL_STATCLOCK] |= imask[IPL_CLOCK];
244 
245 	/*
246 	 * splhigh() must block "everything".
247 	 */
248 	imask[IPL_HIGH] |= imask[IPL_STATCLOCK];
249 
250 	/*
251 	 * XXX We need serial drivers to run at the absolute highest priority
252 	 * in order to avoid overruns, so serial > high.
253 	 */
254 	imask[IPL_SERIAL] |= imask[IPL_HIGH];
255 
256 	/*
257 	 * Now compute which IRQs must be blocked when servicing any
258 	 * given IRQ.
259 	 */
260 	for (irq = 0; irq < NIRQ; irq++) {
261 		int irqs = (1U << irq);
262 		iq = &intrq[irq];
263 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
264 			iq80310_enable_irq(irq);
265 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
266 		     ih = TAILQ_NEXT(ih, ih_list))
267 			irqs |= imask[ih->ih_ipl];
268 		iq->iq_mask = irqs;
269 	}
270 }
271 
272 static void
273 iq80310_do_soft(void)
274 {
275 	static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
276 	int new, oldirqstate;
277 
278 	if (__cpu_simple_lock_try(&processing) == 0)
279 		return;
280 
281 	new = current_spl_level;
282 
283 	oldirqstate = disable_interrupts(I32_bit);
284 
285 #define	DO_SOFTINT(si)							\
286 	if ((ipending & ~new) & SI_TO_IRQBIT(si)) {			\
287 		ipending &= ~SI_TO_IRQBIT(si);				\
288 		current_spl_level |= imask[si_to_ipl[(si)]];		\
289 		restore_interrupts(oldirqstate);			\
290 		softintr_dispatch(si);					\
291 		oldirqstate = disable_interrupts(I32_bit);		\
292 		current_spl_level = new;				\
293 	}
294 
295 	DO_SOFTINT(SI_SOFTSERIAL);
296 	DO_SOFTINT(SI_SOFTNET);
297 	DO_SOFTINT(SI_SOFTCLOCK);
298 	DO_SOFTINT(SI_SOFT);
299 
300 	__cpu_simple_unlock(&processing);
301 
302 	restore_interrupts(oldirqstate);
303 }
304 
305 int
306 _splraise(int ipl)
307 {
308 	int old, oldirqstate;
309 
310 	oldirqstate = disable_interrupts(I32_bit);
311 	old = current_spl_level;
312 	current_spl_level |= imask[ipl];
313 
314 	restore_interrupts(oldirqstate);
315 
316 	return (old);
317 }
318 
319 __inline void
320 splx(int new)
321 {
322 	int old;
323 
324 	old = current_spl_level;
325 	current_spl_level = new;
326 
327 	/* If there are software interrupts to process, do it. */
328 	if ((ipending & ~IRQ_BITS) & ~new)
329 		iq80310_do_soft();
330 
331 	/*
332 	 * If there are pending hardware interrupts (i.e. the
333 	 * external interrupt is disabled in the ICU), and all
334 	 * hardware interrupts are being unblocked, then re-enable
335 	 * the external hardware interrupt.
336 	 *
337 	 * XXX We have to wait for ALL hardware interrupts to
338 	 * XXX be unblocked, because we currently lose if we
339 	 * XXX get nested interrupts, and I don't know why yet.
340 	 */
341 	if ((new & IRQ_BITS) == 0 && (ipending & IRQ_BITS))
342 		i80200_intr_enable(INTCTL_IM);
343 }
344 
345 int
346 _spllower(int ipl)
347 {
348 	int old = current_spl_level;
349 
350 	splx(imask[ipl]);
351 	return (old);
352 }
353 
354 void
355 _setsoftintr(int si)
356 {
357 	int oldirqstate;
358 
359 	oldirqstate = disable_interrupts(I32_bit);
360 	ipending |= SI_TO_IRQBIT(si);
361 	restore_interrupts(oldirqstate);
362 
363 	/* Process unmasked pending soft interrupts. */
364 	if ((ipending & ~IRQ_BITS) & ~current_spl_level)
365 		iq80310_do_soft();
366 }
367 
368 void
369 iq80310_intr_init(void)
370 {
371 	struct intrq *iq;
372 	int i;
373 
374 	/*
375 	 * The Secondary PCI interrupts INTA, INTB, and INTC
376 	 * area always enabled, since they cannot be masked
377 	 * in the CPLD.
378 	 */
379 	intr_enabled |= IRQ_BITS_ALWAYS_ON;
380 
381 	for (i = 0; i < NIRQ; i++) {
382 		iq = &intrq[i];
383 		TAILQ_INIT(&iq->iq_list);
384 
385 		sprintf(iq->iq_name, "irq %d", i);
386 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
387 		    NULL, "iq80310", iq->iq_name);
388 	}
389 
390 	iq80310_intr_calculate_masks();
391 
392 	/* Enable external interrupts on the i80200. */
393 	i80200_extirq_dispatch = iq80310_intr_dispatch;
394 	i80200_intr_enable(INTCTL_IM);
395 
396 	/* Enable IRQs (don't yet use FIQs). */
397 	enable_interrupts(I32_bit);
398 }
399 
400 void *
401 iq80310_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
402 {
403 	struct intrq *iq;
404 	struct intrhand *ih;
405 	u_int oldirqstate;
406 
407 	if (irq < 0 || irq > NIRQ)
408 		panic("iq80310_intr_establish: IRQ %d out of range", irq);
409 
410 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
411 	if (ih == NULL)
412 		return (NULL);
413 
414 	ih->ih_func = func;
415 	ih->ih_arg = arg;
416 	ih->ih_ipl = ipl;
417 	ih->ih_irq = irq;
418 
419 	iq = &intrq[irq];
420 
421 	/* All IQ80310 interrupts are level-triggered. */
422 	iq->iq_ist = IST_LEVEL;
423 
424 	oldirqstate = disable_interrupts(I32_bit);
425 
426 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
427 
428 	iq80310_intr_calculate_masks();
429 
430 	restore_interrupts(oldirqstate);
431 
432 	return (ih);
433 }
434 
435 void
436 iq80310_intr_disestablish(void *cookie)
437 {
438 	struct intrhand *ih = cookie;
439 	struct intrq *iq = &intrq[ih->ih_irq];
440 	int oldirqstate;
441 
442 	oldirqstate = disable_interrupts(I32_bit);
443 
444 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
445 
446 	iq80310_intr_calculate_masks();
447 
448 	restore_interrupts(oldirqstate);
449 }
450 
451 void
452 iq80310_intr_dispatch(struct clockframe *frame)
453 {
454 	struct intrq *iq;
455 	struct intrhand *ih;
456 	int oldirqstate, pcpl, irq, ibit, hwpend;
457 
458 	/* First, disable external IRQs. */
459 	i80200_intr_disable(INTCTL_IM);
460 
461 	pcpl = current_spl_level;
462 
463 	for (hwpend = iq80310_intstat_read(); hwpend != 0;) {
464 		irq = ffs(hwpend) - 1;
465 		ibit = (1U << irq);
466 
467 		hwpend &= ~ibit;
468 
469 		if (pcpl & ibit) {
470 			/*
471 			 * IRQ is masked; mark it as pending and check
472 			 * the next one.  Note: external IRQs are already
473 			 * disabled.
474 			 */
475 			ipending |= ibit;
476 			continue;
477 		}
478 
479 		ipending &= ~ibit;
480 
481 		iq = &intrq[irq];
482 		iq->iq_ev.ev_count++;
483 		uvmexp.intrs++;
484 		current_spl_level |= iq->iq_mask;
485 		oldirqstate = enable_interrupts(I32_bit);
486 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
487 		     ih = TAILQ_NEXT(ih, ih_list)) {
488 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
489 		}
490 		restore_interrupts(oldirqstate);
491 
492 		current_spl_level = pcpl;
493 	}
494 
495 	/* Check for pendings soft intrs. */
496 	if ((ipending & ~IRQ_BITS) & ~current_spl_level) {
497 		oldirqstate = enable_interrupts(I32_bit);
498 		iq80310_do_soft();
499 		restore_interrupts(oldirqstate);
500 	}
501 
502 	/*
503 	 * If no hardware interrupts are masked, re-enable external
504 	 * interrupts.
505 	 */
506 	if ((ipending & IRQ_BITS) == 0)
507 		i80200_intr_enable(INTCTL_IM);
508 }
509