xref: /netbsd-src/sys/arch/arm/xscale/ixp425_intr.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: ixp425_intr.c,v 1.2 2003/06/16 20:00:58 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 2003
5  *	Ichiro FUKUHARA <ichiro@ichiro.org>.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Ichiro FUKUHARA.
19  * 4. The name of the company nor the name of the author may be used to
20  *    endorse or promote products derived from this software without specific
21  *    prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY ICHIRO FUKUHARA ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL ICHIRO FUKUHARA OR THE VOICES IN HIS HEAD BE LIABLE FOR
27  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 /*
36  * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
37  * All rights reserved.
38  *
39  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  * 3. All advertising materials mentioning features or use of this software
50  *    must display the following acknowledgement:
51  *      This product includes software developed for the NetBSD Project by
52  *      Wasabi Systems, Inc.
53  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
54  *    or promote products derived from this software without specific prior
55  *    written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
58  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
59  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
60  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
61  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
62  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
63  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
64  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
65  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
66  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
67  * POSSIBILITY OF SUCH DAMAGE.
68  */
69 
70 #include <sys/cdefs.h>
71 __KERNEL_RCSID(0, "$NetBSD: ixp425_intr.c,v 1.2 2003/06/16 20:00:58 thorpej Exp $");
72 
73 #ifndef EVBARM_SPL_NOINLINE
74 #define	EVBARM_SPL_NOINLINE
75 #endif
76 
77 /*
78  * Interrupt support for the Intel IXP425 NetworkProcessor.
79  */
80 
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/malloc.h>
84 
85 #include <uvm/uvm_extern.h>
86 
87 #include <machine/bus.h>
88 #include <machine/intr.h>
89 
90 #include <arm/cpufunc.h>
91 
92 #include <arm/xscale/ixp425reg.h>
93 #include <arm/xscale/ixp425var.h>
94 
95 /* Interrupt handler queues. */
96 struct intrq intrq[NIRQ];
97 
98 /* Interrupts to mask at each level. */
99 int ixp425_imask[NIPL];
100 
101 /* Current interrupt priority level. */
102 __volatile int current_spl_level;
103 
104 /* Interrupts pending. */
105 __volatile int ixp425_ipending;
106 
107 /* Software copy of the IRQs we have enabled. */
108 __volatile uint32_t intr_enabled;
109 
110 /* Mask if interrupts steered to FIQs. */
111 uint32_t intr_steer;
112 
113 /*
114  * Map a software interrupt queue index
115  */
116 static const uint32_t si_to_irqbit[SI_NQUEUES] = {
117 	IXP425_INT_bit31,		/* SI_SOFT */
118 	IXP425_INT_bit30,		/* SI_SOFTCLOCK */
119 	IXP425_INT_bit29,		/* SI_SOFTNET */
120 	IXP425_INT_bit22,		/* SI_SOFTSERIAL */
121 };
122 
123 #define	SI_TO_IRQBIT(si)	(1U << si_to_irqbit[(si)])
124 
125 /*
126  * Map a software interrupt queue to an interrupt priority level.
127  */
128 static const int si_to_ipl[SI_NQUEUES] = {
129 	IPL_SOFT,		/* SI_SOFT */
130 	IPL_SOFTCLOCK,		/* SI_SOFTCLOCK */
131 	IPL_SOFTNET,		/* SI_SOFTNET */
132 	IPL_SOFTSERIAL,		/* SI_SOFTSERIAL */
133 };
134 
135 void	ixp425_intr_dispatch(struct clockframe *frame);
136 
137 static __inline uint32_t
138 ixp425_irq_read(void)
139 {
140 	return IXPREG(IXP425_INT_STATUS) & intr_enabled;
141 }
142 
143 static __inline void
144 ixp425_set_intrsteer(void)
145 {
146 	IXPREG(IXP425_INT_SELECT) = intr_steer & IXP425_INT_HWMASK;
147 }
148 
149 static __inline void
150 ixp425_enable_irq(int irq)
151 {
152 
153 	intr_enabled |= (1U << irq);
154 	ixp425_set_intrmask();
155 }
156 
157 static __inline void
158 ixp425_disable_irq(int irq)
159 {
160 
161 	intr_enabled &= ~(1U << irq);
162 	ixp425_set_intrmask();
163 }
164 
165 /*
166  * NOTE: This routine must be called with interrupts disabled in the CPSR.
167  */
168 static void
169 ixp425_intr_calculate_masks(void)
170 {
171 	struct intrq *iq;
172 	struct intrhand *ih;
173 	int irq, ipl;
174 
175 	/* First, figure out which IPLs each IRQ has. */
176 	for (irq = 0; irq < NIRQ; irq++) {
177 		int levels = 0;
178 		iq = &intrq[irq];
179 		ixp425_disable_irq(irq);
180 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
181 		     ih = TAILQ_NEXT(ih, ih_list))
182 			levels |= (1U << ih->ih_ipl);
183 		iq->iq_levels = levels;
184 	}
185 
186 	/* Next, figure out which IRQs are used by each IPL. */
187 	for (ipl = 0; ipl < NIPL; ipl++) {
188 		int irqs = 0;
189 		for (irq = 0; irq < NIRQ; irq++) {
190 			if (intrq[irq].iq_levels & (1U << ipl))
191 				irqs |= (1U << irq);
192 		}
193 		ixp425_imask[ipl] = irqs;
194 	}
195 
196 	ixp425_imask[IPL_NONE] = 0;
197 
198 	/*
199 	 * Initialize the soft interrupt masks to block themselves.
200 	 */
201 	ixp425_imask[IPL_SOFT] = SI_TO_IRQBIT(SI_SOFT);
202 	ixp425_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
203 	ixp425_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
204 	ixp425_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
205 
206 	/*
207 	 * splsoftclock() is the only interface that users of the
208 	 * generic software interrupt facility have to block their
209 	 * soft intrs, so splsoftclock() must also block IPL_SOFT.
210 	 */
211 	ixp425_imask[IPL_SOFTCLOCK] |= ixp425_imask[IPL_SOFT];
212 
213 	/*
214 	 * splsoftnet() must also block splsoftclock(), since we don't
215 	 * want timer-driven network events to occur while we're
216 	 * processing incoming packets.
217 	 */
218 	ixp425_imask[IPL_SOFTNET] |= ixp425_imask[IPL_SOFTCLOCK];
219 
220 	/*
221 	 * Enforce a heirarchy that gives "slow" device (or devices with
222 	 * limited input buffer space/"real-time" requirements) a better
223 	 * chance at not dropping data.
224 	 */
225 	ixp425_imask[IPL_BIO] |= ixp425_imask[IPL_SOFTNET];
226 	ixp425_imask[IPL_NET] |= ixp425_imask[IPL_BIO];
227 	ixp425_imask[IPL_SOFTSERIAL] |= ixp425_imask[IPL_NET];
228 	ixp425_imask[IPL_TTY] |= ixp425_imask[IPL_SOFTSERIAL];
229 
230 	/*
231 	 * splvm() blocks all interrupts that use the kernel memory
232 	 * allocation facilities.
233 	 */
234 	ixp425_imask[IPL_VM] |= ixp425_imask[IPL_TTY];
235 
236 	/*
237 	 * Audio devices are not allowed to perform memory allocation
238 	 * in their interrupt routines, and they have fairly "real-time"
239 	 * requirements, so give them a high interrupt priority.
240 	 */
241 	ixp425_imask[IPL_AUDIO] |= ixp425_imask[IPL_VM];
242 
243 	/*
244 	 * splclock() must block anything that uses the scheduler.
245 	 */
246 	ixp425_imask[IPL_CLOCK] |= ixp425_imask[IPL_AUDIO];
247 
248 	/*
249 	 * No separate statclock on the IQ80310.
250 	 */
251 	ixp425_imask[IPL_STATCLOCK] |= ixp425_imask[IPL_CLOCK];
252 
253 	/*
254 	 * splhigh() must block "everything".
255 	 */
256 	ixp425_imask[IPL_HIGH] |= ixp425_imask[IPL_STATCLOCK];
257 
258 	/*
259 	 * XXX We need serial drivers to run at the absolute highest priority
260 	 * in order to avoid overruns, so serial > high.
261 	 */
262 	ixp425_imask[IPL_SERIAL] |= ixp425_imask[IPL_HIGH];
263 
264 	/*
265 	 * Now compute which IRQs must be blocked when servicing any
266 	 * given IRQ.
267 	 */
268 	for (irq = 0; irq < NIRQ; irq++) {
269 		int irqs = (1U << irq);
270 		iq = &intrq[irq];
271 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
272 			ixp425_enable_irq(irq);
273 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
274 		     ih = TAILQ_NEXT(ih, ih_list))
275 			irqs |= ixp425_imask[ih->ih_ipl];
276 		iq->iq_mask = irqs;
277 	}
278 }
279 
280 __inline void
281 ixp425_do_pending(void)
282 {
283 	static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
284 	int new, oldirqstate;
285 
286 	if (__cpu_simple_lock_try(&processing) == 0)
287 		return;
288 
289 	new = current_spl_level;
290 
291 	oldirqstate = disable_interrupts(I32_bit);
292 
293 #define	DO_SOFTINT(si)							\
294 	if ((ixp425_ipending & ~new) & SI_TO_IRQBIT(si)) {		\
295 		ixp425_ipending &= ~SI_TO_IRQBIT(si);			\
296 		current_spl_level |= ixp425_imask[si_to_ipl[(si)]];	\
297 		restore_interrupts(oldirqstate);			\
298 		softintr_dispatch(si);					\
299 		oldirqstate = disable_interrupts(I32_bit);		\
300 		current_spl_level = new;				\
301 	}
302 
303 	DO_SOFTINT(SI_SOFTSERIAL);
304 	DO_SOFTINT(SI_SOFTNET);
305 	DO_SOFTINT(SI_SOFTCLOCK);
306 	DO_SOFTINT(SI_SOFT);
307 
308 	__cpu_simple_unlock(&processing);
309 
310 	restore_interrupts(oldirqstate);
311 }
312 
313 void
314 splx(int new)
315 {
316 
317 	ixp425_splx(new);
318 }
319 
320 int
321 _spllower(int ipl)
322 {
323 
324 	return (ixp425_spllower(ipl));
325 }
326 
327 int
328 _splraise(int ipl)
329 {
330 
331 	return (ixp425_splraise(ipl));
332 }
333 
334 void
335 _setsoftintr(int si)
336 {
337 	int oldirqstate;
338 
339 	oldirqstate = disable_interrupts(I32_bit);
340 	ixp425_ipending |= SI_TO_IRQBIT(si);
341 	restore_interrupts(oldirqstate);
342 
343 	/* Process unmasked pending soft interrupts. */
344 	if ((ixp425_ipending & INT_SWMASK) & ~current_spl_level)
345 		ixp425_do_pending();
346 }
347 
348 /*
349  * ixp425_icu_init:
350  *
351  * 	Called early in bootstrap to make clear interrupt register
352  */
353 void
354 ixp425_icu_init(void)
355 {
356 
357 	intr_enabled = 0;	/* All interrupts disabled */
358 	ixp425_set_intrmask();
359 
360 	intr_steer = 0;		/* All interrupts steered to IRQ */
361 	ixp425_set_intrsteer();
362 }
363 
364 /*
365  * ixp425_intr_init:
366  *
367  *	Initialize the rest of the interrupt subsystem, making it
368  *	ready to handle interrupts from devices.
369  */
370 void
371 ixp425_intr_init(void)
372 {
373 	struct intrq *iq;
374 	int i;
375 
376 	intr_enabled = 0;
377 
378 	for (i = 0; i < NIRQ; i++) {
379 		iq = &intrq[i];
380 		TAILQ_INIT(&iq->iq_list);
381 
382 		sprintf(iq->iq_name, "irq %d", i);
383 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
384 				     NULL, "ixp425", iq->iq_name);
385 	}
386 
387 	ixp425_intr_calculate_masks();
388 
389 	/* Enable IRQs (don't yet use FIQs). */
390 	enable_interrupts(I32_bit);
391 }
392 
393 void *
394 ixp425_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
395 {
396 	struct intrq *iq;
397 	struct intrhand *ih;
398 	u_int oldirqstate;
399 
400 	if (irq < 0 || irq > NIRQ)
401 		panic("ixp425_intr_establish: IRQ %d out of range", irq);
402 #ifdef DEBUG
403 	printf("ixp425_intr_establish(irq=%d, ipl=%d, func=%08x, arg=%08x)\n",
404                irq, ipl, (u_int32_t) func, (u_int32_t) arg);
405 #endif
406 
407 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
408 	if (ih == NULL)
409 		return (NULL);
410 
411 	ih->ih_func = func;
412 	ih->ih_arg = arg;
413 	ih->ih_ipl = ipl;
414 	ih->ih_irq = irq;
415 
416 	iq = &intrq[irq];
417 
418 	/* All IXP425 interrupts are level-triggered. */
419 	iq->iq_ist = IST_LEVEL; /* XXX */
420 
421 	oldirqstate = disable_interrupts(I32_bit);
422 
423 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
424 
425 	ixp425_intr_calculate_masks();
426 
427 	restore_interrupts(oldirqstate);
428 
429 	return (ih);
430 }
431 
432 void
433 ixp425_intr_disestablish(void *cookie)
434 {
435 	struct intrhand *ih = cookie;
436 	struct intrq *iq = &intrq[ih->ih_irq];
437 	int oldirqstate;
438 
439 	oldirqstate = disable_interrupts(I32_bit);
440 
441 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
442 
443 	ixp425_intr_calculate_masks();
444 
445 	restore_interrupts(oldirqstate);
446 }
447 
448 void
449 ixp425_intr_dispatch(struct clockframe *frame)
450 {
451 	struct intrq *iq;
452 	struct intrhand *ih;
453 	int oldirqstate, pcpl, irq, ibit, hwpend;
454 
455 	pcpl = current_spl_level;
456 
457 	hwpend = ixp425_irq_read();
458 
459 	/*
460 	 * Disable all the interrupts that are pending.  We will
461 	 * reenable them once they are processed and not masked.
462 	 */
463 	intr_enabled &= ~hwpend;
464 	ixp425_set_intrmask();
465 
466 	while (hwpend != 0) {
467 		irq = ffs(hwpend) - 1;
468 		ibit = (1U << irq);
469 
470 		hwpend &= ~ibit;
471 
472 		if (pcpl & ibit) {
473 			/*
474 			 * IRQ is masked; mark it as pending and check
475 			 * the next one.  Note: the IRQ is already disabled.
476 			 */
477 			ixp425_ipending |= ibit;
478 			continue;
479 		}
480 
481 		ixp425_ipending &= ~ibit;
482 
483 		iq = &intrq[irq];
484 		iq->iq_ev.ev_count++;
485 		uvmexp.intrs++;
486 		current_spl_level |= iq->iq_mask;
487 		oldirqstate = enable_interrupts(I32_bit);
488 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
489 		     ih = TAILQ_NEXT(ih, ih_list)) {
490 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
491 		}
492 		restore_interrupts(oldirqstate);
493 
494 		current_spl_level = pcpl;
495 
496 		/* Re-enable this interrupt now that's it's cleared. */
497 		intr_enabled |= ibit;
498 		ixp425_set_intrmask();
499 	}
500 
501 	/* Check for pendings soft intrs. */
502 	if ((ixp425_ipending & INT_SWMASK) & ~current_spl_level) {
503 		oldirqstate = enable_interrupts(I32_bit);
504 		ixp425_do_pending();
505 		restore_interrupts(oldirqstate);
506 	}
507 }
508