iq80310_intr.c revision 1.23 1 /* $NetBSD: iq80310_intr.c,v 1.23 2005/12/24 20:06:59 perry 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 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: iq80310_intr.c,v 1.23 2005/12/24 20:06:59 perry Exp $");
40
41 #ifndef EVBARM_SPL_NOINLINE
42 #define EVBARM_SPL_NOINLINE
43 #endif
44
45 /*
46 * Interrupt support for the Intel IQ80310.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/malloc.h>
52
53 #include <uvm/uvm_extern.h>
54
55 #include <machine/bus.h>
56 #include <machine/intr.h>
57
58 #include <arm/cpufunc.h>
59
60 #include <arm/xscale/i80200reg.h>
61 #include <arm/xscale/i80200var.h>
62
63 #include <evbarm/iq80310/iq80310reg.h>
64 #include <evbarm/iq80310/iq80310var.h>
65 #include <evbarm/iq80310/obiovar.h>
66
67 /* Interrupt handler queues. */
68 struct intrq intrq[NIRQ];
69
70 /* Interrupts to mask at each level. */
71 int iq80310_imask[NIPL];
72
73 /* Current interrupt priority level. */
74 volatile int current_spl_level;
75
76 /* Interrupts pending. */
77 volatile int iq80310_ipending;
78
79 /* Software copy of the IRQs we have enabled. */
80 uint32_t intr_enabled;
81
82 /*
83 * Map a software interrupt queue index (at the top of the word, and
84 * highest priority softintr is encountered first in an ffs()).
85 */
86 #define SI_TO_IRQBIT(si) (1U << (31 - (si)))
87
88 /*
89 * Map a software interrupt queue to an interrupt priority level.
90 */
91 static const int si_to_ipl[SI_NQUEUES] = {
92 IPL_SOFT, /* SI_SOFT */
93 IPL_SOFTCLOCK, /* SI_SOFTCLOCK */
94 IPL_SOFTNET, /* SI_SOFTNET */
95 IPL_SOFTSERIAL, /* SI_SOFTSERIAL */
96 };
97
98 void iq80310_intr_dispatch(struct irqframe *frame);
99
100 static inline uint32_t
101 iq80310_intstat_read(void)
102 {
103 uint32_t intstat;
104
105 intstat = CPLD_READ(IQ80310_XINT3_STATUS) & 0x1f;
106 #if defined(IRQ_READ_XINT0)
107 if (IRQ_READ_XINT0)
108 intstat |= (CPLD_READ(IQ80310_XINT0_STATUS) & 0x7) << 5;
109 #endif
110
111 /* XXX Why do we have to mask off? */
112 return (intstat & intr_enabled);
113 }
114
115 static inline void
116 iq80310_set_intrmask(void)
117 {
118 uint32_t disabled;
119
120 intr_enabled |= IRQ_BITS_ALWAYS_ON;
121
122 /* The XINT_MASK register sets a bit to *disable*. */
123 disabled = (~intr_enabled) & IRQ_BITS;
124
125 CPLD_WRITE(IQ80310_XINT_MASK, disabled & 0x1f);
126 }
127
128 static inline void
129 iq80310_enable_irq(int irq)
130 {
131
132 intr_enabled |= (1U << irq);
133 iq80310_set_intrmask();
134 }
135
136 static inline void
137 iq80310_disable_irq(int irq)
138 {
139
140 intr_enabled &= ~(1U << irq);
141 iq80310_set_intrmask();
142 }
143
144 /*
145 * NOTE: This routine must be called with interrupts disabled in the CPSR.
146 */
147 static void
148 iq80310_intr_calculate_masks(void)
149 {
150 struct intrq *iq;
151 struct intrhand *ih;
152 int irq, ipl;
153
154 /* First, figure out which IPLs each IRQ has. */
155 for (irq = 0; irq < NIRQ; irq++) {
156 int levels = 0;
157 iq = &intrq[irq];
158 iq80310_disable_irq(irq);
159 for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
160 ih = TAILQ_NEXT(ih, ih_list))
161 levels |= (1U << ih->ih_ipl);
162 iq->iq_levels = levels;
163 }
164
165 /* Next, figure out which IRQs are used by each IPL. */
166 for (ipl = 0; ipl < NIPL; ipl++) {
167 int irqs = 0;
168 for (irq = 0; irq < NIRQ; irq++) {
169 if (intrq[irq].iq_levels & (1U << ipl))
170 irqs |= (1U << irq);
171 }
172 iq80310_imask[ipl] = irqs;
173 }
174
175 iq80310_imask[IPL_NONE] = 0;
176
177 /*
178 * Initialize the soft interrupt masks to block themselves.
179 */
180 iq80310_imask[IPL_SOFT] = SI_TO_IRQBIT(SI_SOFT);
181 iq80310_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
182 iq80310_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
183 iq80310_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
184
185 /*
186 * splsoftclock() is the only interface that users of the
187 * generic software interrupt facility have to block their
188 * soft intrs, so splsoftclock() must also block IPL_SOFT.
189 */
190 iq80310_imask[IPL_SOFTCLOCK] |= iq80310_imask[IPL_SOFT];
191
192 /*
193 * splsoftnet() must also block splsoftclock(), since we don't
194 * want timer-driven network events to occur while we're
195 * processing incoming packets.
196 */
197 iq80310_imask[IPL_SOFTNET] |= iq80310_imask[IPL_SOFTCLOCK];
198
199 /*
200 * Enforce a heirarchy that gives "slow" device (or devices with
201 * limited input buffer space/"real-time" requirements) a better
202 * chance at not dropping data.
203 */
204 iq80310_imask[IPL_BIO] |= iq80310_imask[IPL_SOFTNET];
205 iq80310_imask[IPL_NET] |= iq80310_imask[IPL_BIO];
206 iq80310_imask[IPL_SOFTSERIAL] |= iq80310_imask[IPL_NET];
207 iq80310_imask[IPL_TTY] |= iq80310_imask[IPL_SOFTSERIAL];
208
209 /*
210 * splvm() blocks all interrupts that use the kernel memory
211 * allocation facilities.
212 */
213 iq80310_imask[IPL_VM] |= iq80310_imask[IPL_TTY];
214
215 /*
216 * Audio devices are not allowed to perform memory allocation
217 * in their interrupt routines, and they have fairly "real-time"
218 * requirements, so give them a high interrupt priority.
219 */
220 iq80310_imask[IPL_AUDIO] |= iq80310_imask[IPL_VM];
221
222 /*
223 * splclock() must block anything that uses the scheduler.
224 */
225 iq80310_imask[IPL_CLOCK] |= iq80310_imask[IPL_AUDIO];
226
227 /*
228 * No separate statclock on the IQ80310.
229 */
230 iq80310_imask[IPL_STATCLOCK] |= iq80310_imask[IPL_CLOCK];
231
232 /*
233 * splhigh() must block "everything".
234 */
235 iq80310_imask[IPL_HIGH] |= iq80310_imask[IPL_STATCLOCK];
236
237 /*
238 * XXX We need serial drivers to run at the absolute highest priority
239 * in order to avoid overruns, so serial > high.
240 */
241 iq80310_imask[IPL_SERIAL] |= iq80310_imask[IPL_HIGH];
242
243 /*
244 * Now compute which IRQs must be blocked when servicing any
245 * given IRQ.
246 */
247 for (irq = 0; irq < NIRQ; irq++) {
248 int irqs = (1U << irq);
249 iq = &intrq[irq];
250 if (TAILQ_FIRST(&iq->iq_list) != NULL)
251 iq80310_enable_irq(irq);
252 for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
253 ih = TAILQ_NEXT(ih, ih_list))
254 irqs |= iq80310_imask[ih->ih_ipl];
255 iq->iq_mask = irqs;
256 }
257 }
258
259 void
260 iq80310_do_soft(void)
261 {
262 static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
263 int new, oldirqstate;
264
265 if (__cpu_simple_lock_try(&processing) == 0)
266 return;
267
268 new = current_spl_level;
269
270 oldirqstate = disable_interrupts(I32_bit);
271
272 #define DO_SOFTINT(si) \
273 if ((iq80310_ipending & ~new) & SI_TO_IRQBIT(si)) { \
274 iq80310_ipending &= ~SI_TO_IRQBIT(si); \
275 current_spl_level |= iq80310_imask[si_to_ipl[(si)]]; \
276 restore_interrupts(oldirqstate); \
277 softintr_dispatch(si); \
278 oldirqstate = disable_interrupts(I32_bit); \
279 current_spl_level = new; \
280 }
281
282 DO_SOFTINT(SI_SOFTSERIAL);
283 DO_SOFTINT(SI_SOFTNET);
284 DO_SOFTINT(SI_SOFTCLOCK);
285 DO_SOFTINT(SI_SOFT);
286
287 __cpu_simple_unlock(&processing);
288
289 restore_interrupts(oldirqstate);
290 }
291
292 int
293 _splraise(int ipl)
294 {
295
296 return (iq80310_splraise(ipl));
297 }
298
299 inline void
300 splx(int new)
301 {
302
303 return (iq80310_splx(new));
304 }
305
306 int
307 _spllower(int ipl)
308 {
309
310 return (iq80310_spllower(ipl));
311 }
312
313 void
314 _setsoftintr(int si)
315 {
316 int oldirqstate;
317
318 oldirqstate = disable_interrupts(I32_bit);
319 iq80310_ipending |= SI_TO_IRQBIT(si);
320 restore_interrupts(oldirqstate);
321
322 /* Process unmasked pending soft interrupts. */
323 if ((iq80310_ipending & ~IRQ_BITS) & ~current_spl_level)
324 iq80310_do_soft();
325 }
326
327 void
328 iq80310_intr_init(void)
329 {
330 struct intrq *iq;
331 int i;
332
333 /*
334 * The Secondary PCI interrupts INTA, INTB, and INTC
335 * area always enabled, since they cannot be masked
336 * in the CPLD.
337 */
338 intr_enabled |= IRQ_BITS_ALWAYS_ON;
339
340 for (i = 0; i < NIRQ; i++) {
341 iq = &intrq[i];
342 TAILQ_INIT(&iq->iq_list);
343
344 sprintf(iq->iq_name, "irq %d", i);
345 evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
346 NULL, "iq80310", iq->iq_name);
347 }
348
349 iq80310_intr_calculate_masks();
350
351 /* Enable external interrupts on the i80200. */
352 i80200_extirq_dispatch = iq80310_intr_dispatch;
353 i80200_intr_enable(INTCTL_IM | INTCTL_PM);
354
355 /* Enable IRQs (don't yet use FIQs). */
356 enable_interrupts(I32_bit);
357 }
358
359 void *
360 iq80310_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
361 {
362 struct intrq *iq;
363 struct intrhand *ih;
364 u_int oldirqstate;
365
366 if (irq < 0 || irq > NIRQ)
367 panic("iq80310_intr_establish: IRQ %d out of range", irq);
368
369 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
370 if (ih == NULL)
371 return (NULL);
372
373 ih->ih_func = func;
374 ih->ih_arg = arg;
375 ih->ih_ipl = ipl;
376 ih->ih_irq = irq;
377
378 iq = &intrq[irq];
379
380 /* All IQ80310 interrupts are level-triggered. */
381 iq->iq_ist = IST_LEVEL;
382
383 oldirqstate = disable_interrupts(I32_bit);
384
385 TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
386
387 iq80310_intr_calculate_masks();
388
389 restore_interrupts(oldirqstate);
390
391 return (ih);
392 }
393
394 void
395 iq80310_intr_disestablish(void *cookie)
396 {
397 struct intrhand *ih = cookie;
398 struct intrq *iq = &intrq[ih->ih_irq];
399 int oldirqstate;
400
401 oldirqstate = disable_interrupts(I32_bit);
402
403 TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
404
405 iq80310_intr_calculate_masks();
406
407 restore_interrupts(oldirqstate);
408 }
409
410 void
411 iq80310_intr_dispatch(struct irqframe *frame)
412 {
413 struct intrq *iq;
414 struct intrhand *ih;
415 int oldirqstate, pcpl, irq, ibit, hwpend, rv, stray;
416
417 stray = 1;
418
419 /* First, disable external IRQs. */
420 i80200_intr_disable(INTCTL_IM | INTCTL_PM);
421
422 pcpl = current_spl_level;
423
424 for (hwpend = iq80310_intstat_read(); hwpend != 0;) {
425 irq = ffs(hwpend) - 1;
426 ibit = (1U << irq);
427
428 stray = 0;
429
430 hwpend &= ~ibit;
431
432 if (pcpl & ibit) {
433 /*
434 * IRQ is masked; mark it as pending and check
435 * the next one. Note: external IRQs are already
436 * disabled.
437 */
438 iq80310_ipending |= ibit;
439 continue;
440 }
441
442 iq80310_ipending &= ~ibit;
443 rv = 0;
444
445 iq = &intrq[irq];
446 iq->iq_ev.ev_count++;
447 uvmexp.intrs++;
448 current_spl_level |= iq->iq_mask;
449 oldirqstate = enable_interrupts(I32_bit);
450 for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
451 ih = TAILQ_NEXT(ih, ih_list)) {
452 rv |= (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
453 }
454 restore_interrupts(oldirqstate);
455
456 current_spl_level = pcpl;
457
458 #if 0 /* XXX */
459 if (rv == 0)
460 printf("Stray interrupt: IRQ %d\n", irq);
461 #endif
462 }
463
464 #if 0 /* XXX */
465 if (stray)
466 printf("Stray external interrupt\n");
467 #endif
468
469 /* Check for pendings soft intrs. */
470 if ((iq80310_ipending & ~IRQ_BITS) & ~current_spl_level) {
471 oldirqstate = enable_interrupts(I32_bit);
472 iq80310_do_soft();
473 restore_interrupts(oldirqstate);
474 }
475
476 /*
477 * If no hardware interrupts are masked, re-enable external
478 * interrupts.
479 */
480 if ((iq80310_ipending & IRQ_BITS) == 0)
481 i80200_intr_enable(INTCTL_IM | INTCTL_PM);
482 }
483