xref: /openbsd/sys/dev/ic/aic7xxx_inline.h (revision 17df1aa7)
1 /*	$OpenBSD: aic7xxx_inline.h,v 1.14 2007/05/14 01:37:49 deraadt Exp $	*/
2 /*	$NetBSD: aic7xxx_inline.h,v 1.4 2003/11/02 11:07:44 wiz Exp $	*/
3 
4 /*
5  * Inline routines shareable across OS platforms.
6  *
7  * Copyright (c) 1994-2001 Justin T. Gibbs.
8  * Copyright (c) 2000-2001 Adaptec Inc.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  *
43  * //depot/aic7xxx/aic7xxx/aic7xxx_inline.h#39 $
44  *
45  * $FreeBSD: /repoman/r/ncvs/src/sys/dev/aic7xxx/aic7xxx_inline.h,v 1.20 2003/01/20 20:44:55 gibbs Exp $
46  */
47 /*
48  * Ported from FreeBSD by Pascal Renauld, Network Storage Solutions, Inc. - April 2003
49  */
50 
51 #ifndef _AIC7XXX_INLINE_H_
52 #define _AIC7XXX_INLINE_H_
53 
54 #ifdef SMALL_KERNEL
55 #define	IO_INLINE
56 #else
57 #define	IO_INLINE	static __inline
58 #define	IO_EXPAND
59 #endif
60 
61 /************************* Sequencer Execution Control ************************/
62 IO_INLINE void ahc_pause_bug_fix(struct ahc_softc *ahc);
63 IO_INLINE int  ahc_is_paused(struct ahc_softc *ahc);
64 IO_INLINE void ahc_pause(struct ahc_softc *ahc);
65 IO_INLINE void ahc_unpause(struct ahc_softc *ahc);
66 
67 #ifdef IO_EXPAND
68 /*
69  * Work around any chip bugs related to halting sequencer execution.
70  * On Ultra2 controllers, we must clear the CIOBUS stretch signal by
71  * reading a register that will set this signal and deassert it.
72  * Without this workaround, if the chip is paused, by an interrupt or
73  * manual pause while accessing scb ram, accesses to certain registers
74  * will hang the system (infinite pci retries).
75  */
76 IO_INLINE void
77 ahc_pause_bug_fix(struct ahc_softc *ahc)
78 {
79 	if ((ahc->features & AHC_ULTRA2) != 0)
80 		(void)ahc_inb(ahc, CCSCBCTL);
81 }
82 
83 /*
84  * Determine whether the sequencer has halted code execution.
85  * Returns non-zero status if the sequencer is stopped.
86  */
87 IO_INLINE int
88 ahc_is_paused(struct ahc_softc *ahc)
89 {
90 	return ((ahc_inb(ahc, HCNTRL) & PAUSE) != 0);
91 }
92 
93 /*
94  * Request that the sequencer stop and wait, indefinitely, for it
95  * to stop.  The sequencer will only acknowledge that it is paused
96  * once it has reached an instruction boundary and PAUSEDIS is
97  * cleared in the SEQCTL register.  The sequencer may use PAUSEDIS
98  * for critical sections.
99  */
100 IO_INLINE void
101 ahc_pause(struct ahc_softc *ahc)
102 {
103 	ahc_outb(ahc, HCNTRL, ahc->pause);
104 
105 	/*
106 	 * Since the sequencer can disable pausing in a critical section, we
107 	 * must loop until it actually stops.
108 	 */
109 	while (ahc_is_paused(ahc) == 0)
110 		;
111 
112 	ahc_pause_bug_fix(ahc);
113 }
114 
115 /*
116  * Allow the sequencer to continue program execution.
117  * We check here to ensure that no additional interrupt
118  * sources that would cause the sequencer to halt have been
119  * asserted.  If, for example, a SCSI bus reset is detected
120  * while we are fielding a different, pausing, interrupt type,
121  * we don't want to release the sequencer before going back
122  * into our interrupt handler and dealing with this new
123  * condition.
124  */
125 IO_INLINE void
126 ahc_unpause(struct ahc_softc *ahc)
127 {
128 	if ((ahc_inb(ahc, INTSTAT) & (SCSIINT | SEQINT | BRKADRINT)) == 0)
129 		ahc_outb(ahc, HCNTRL, ahc->unpause);
130 }
131 #endif /* IO_EXPAND */
132 
133 /*********************** Untagged Transaction Routines ************************/
134 IO_INLINE void	ahc_freeze_untagged_queues(struct ahc_softc *ahc);
135 IO_INLINE void	ahc_release_untagged_queues(struct ahc_softc *ahc);
136 
137 #ifdef IO_EXPAND
138 /*
139  * Block our completion routine from starting the next untagged
140  * transaction for this target or target lun.
141  */
142 IO_INLINE void
143 ahc_freeze_untagged_queues(struct ahc_softc *ahc)
144 {
145 	if ((ahc->flags & AHC_SCB_BTT) == 0)
146 		ahc->untagged_queue_lock++;
147 }
148 
149 /*
150  * Allow the next untagged transaction for this target or target lun
151  * to be executed.  We use a counting semaphore to allow the lock
152  * to be acquired recursively.  Once the count drops to zero, the
153  * transaction queues will be run.
154  */
155 IO_INLINE void
156 ahc_release_untagged_queues(struct ahc_softc *ahc)
157 {
158 	if ((ahc->flags & AHC_SCB_BTT) == 0) {
159 		ahc->untagged_queue_lock--;
160 		if (ahc->untagged_queue_lock == 0)
161 			ahc_run_untagged_queues(ahc);
162 	}
163 }
164 #endif /* IO_EXPAND */
165 
166 
167 /************************** Memory mapping routines ***************************/
168 IO_INLINE struct ahc_dma_seg *
169 			ahc_sg_bus_to_virt(struct scb *scb,
170 					   uint32_t sg_busaddr);
171 IO_INLINE uint32_t
172 			ahc_sg_virt_to_bus(struct scb *scb,
173 					   struct ahc_dma_seg *sg);
174 IO_INLINE uint32_t
175 			ahc_hscb_busaddr(struct ahc_softc *ahc, u_int index);
176 IO_INLINE void		ahc_sync_scb(struct ahc_softc *ahc,
177 					   struct scb *scb, int op);
178 #ifdef AHC_TARGET_MODE
179 IO_INLINE uint32_t
180 			ahc_targetcmd_offset(struct ahc_softc *ahc,
181 					     u_int index);
182 #endif
183 
184 #ifdef IO_EXPAND
185 
186 IO_INLINE struct ahc_dma_seg *
187 ahc_sg_bus_to_virt(struct scb *scb, uint32_t sg_busaddr)
188 {
189 	int sg_index;
190 
191 	sg_index = (sg_busaddr - scb->sg_list_phys)/sizeof(struct ahc_dma_seg);
192 	/* sg_list_phys points to entry 1, not 0 */
193 	sg_index++;
194 
195 	return (&scb->sg_list[sg_index]);
196 }
197 
198 IO_INLINE uint32_t
199 ahc_sg_virt_to_bus(struct scb *scb, struct ahc_dma_seg *sg)
200 {
201 	int sg_index;
202 
203 	/* sg_list_phys points to entry 1, not 0 */
204 	sg_index = sg - &scb->sg_list[1];
205 
206 	return (scb->sg_list_phys + (sg_index * sizeof(*scb->sg_list)));
207 }
208 
209 IO_INLINE uint32_t
210 ahc_hscb_busaddr(struct ahc_softc *ahc, u_int index)
211 {
212 	return (ahc->scb_data->hscb_busaddr
213 		+ (sizeof(struct hardware_scb) * index));
214 }
215 
216 IO_INLINE void
217 ahc_sync_scb(struct ahc_softc *ahc, struct scb *scb, int op)
218 {
219 	ahc_dmamap_sync(ahc, ahc->parent_dmat,
220 			ahc->scb_data->hscb_dmamap,
221 			/*offset*/(scb->hscb - ahc->scb_data->hscbs) * sizeof(*scb->hscb),
222 			/*len*/sizeof(*scb->hscb), op);
223 }
224 
225 #ifdef AHC_TARGET_MODE
226 IO_INLINE uint32_t
227 ahc_targetcmd_offset(struct ahc_softc *ahc, u_int index)
228 {
229 	return (((uint8_t *)&ahc->targetcmds[index]) - ahc->qoutfifo);
230 }
231 #endif /* AHC_TARGET_MODE */
232 #endif /* IO_EXPAND */
233 
234 /******************************** Debugging ***********************************/
235 static __inline char *ahc_name(struct ahc_softc *ahc);
236 
237 static __inline char *
238 ahc_name(struct ahc_softc *ahc)
239 {
240 	return (ahc->name);
241 }
242 
243 /*********************** Miscellaneous Support Functions ***********************/
244 
245 IO_INLINE void	ahc_update_residual(struct ahc_softc *ahc,
246 					    struct scb *scb);
247 IO_INLINE struct ahc_initiator_tinfo *
248 			ahc_fetch_transinfo(struct ahc_softc *ahc,
249 					    char channel, u_int our_id,
250 					    u_int remote_id,
251 					    struct ahc_tmode_tstate **tstate);
252 
253 IO_INLINE uint16_t
254 			ahc_inw(struct ahc_softc *ahc, u_int port);
255 IO_INLINE void	ahc_outw(struct ahc_softc *ahc, u_int port,
256 				 u_int value);
257 IO_INLINE uint32_t
258 			ahc_inl(struct ahc_softc *ahc, u_int port);
259 IO_INLINE void	ahc_outl(struct ahc_softc *ahc, u_int port,
260 				 uint32_t value);
261 IO_INLINE struct scb*
262 			ahc_get_scb(struct ahc_softc *ahc);
263 IO_INLINE void		ahc_free_scb(struct ahc_softc *ahc, struct scb *scb);
264 IO_INLINE struct scb *ahc_lookup_scb(struct ahc_softc *ahc, u_int tag);
265 IO_INLINE void		ahc_swap_with_next_hscb(struct ahc_softc *ahc,
266 						struct scb *scb);
267 IO_INLINE void		ahc_queue_scb(struct ahc_softc *ahc, struct scb *scb);
268 IO_INLINE struct scsi_sense_data *
269 			ahc_get_sense_buf(struct ahc_softc *ahc,
270 					  struct scb *scb);
271 IO_INLINE uint32_t
272 			ahc_get_sense_bufaddr(struct ahc_softc *ahc,
273 					      struct scb *scb);
274 
275 #ifdef IO_EXPAND
276 
277 /*
278  * Determine whether the sequencer reported a residual
279  * for this SCB/transaction.
280  */
281 IO_INLINE void
282 ahc_update_residual(struct ahc_softc *ahc, struct scb *scb)
283 {
284 	uint32_t sgptr;
285 
286 	sgptr = aic_le32toh(scb->hscb->sgptr);
287 	if ((sgptr & SG_RESID_VALID) != 0)
288 		ahc_calc_residual(ahc, scb);
289 }
290 
291 /*
292  * Return pointers to the transfer negotiation information
293  * for the specified our_id/remote_id pair.
294  */
295 IO_INLINE struct ahc_initiator_tinfo *
296 ahc_fetch_transinfo(struct ahc_softc *ahc, char channel, u_int our_id,
297 		    u_int remote_id, struct ahc_tmode_tstate **tstate)
298 {
299 	/*
300 	 * Transfer data structures are stored from the perspective
301 	 * of the target role.  Since the parameters for a connection
302 	 * in the initiator role to a given target are the same as
303 	 * when the roles are reversed, we pretend we are the target.
304 	 */
305 	/*if (channel == 'B')
306 	  our_id += 8;*/
307 	*tstate = ahc->enabled_targets[our_id];
308 	return (&(*tstate)->transinfo[remote_id]);
309 }
310 
311 IO_INLINE uint16_t
312 ahc_inw(struct ahc_softc *ahc, u_int port)
313 {
314 	return ((ahc_inb(ahc, port+1) << 8) | ahc_inb(ahc, port));
315 }
316 
317 IO_INLINE void
318 ahc_outw(struct ahc_softc *ahc, u_int port, u_int value)
319 {
320 	ahc_outb(ahc, port, value & 0xFF);
321 	ahc_outb(ahc, port+1, (value >> 8) & 0xFF);
322 }
323 
324 IO_INLINE uint32_t
325 ahc_inl(struct ahc_softc *ahc, u_int port)
326 {
327 	return ((ahc_inb(ahc, port))
328 	      | (ahc_inb(ahc, port+1) << 8)
329 	      | (ahc_inb(ahc, port+2) << 16)
330 	      | (ahc_inb(ahc, port+3) << 24));
331 }
332 
333 IO_INLINE void
334 ahc_outl(struct ahc_softc *ahc, u_int port, uint32_t value)
335 {
336 	ahc_outb(ahc, port, (value) & 0xFF);
337 	ahc_outb(ahc, port+1, ((value) >> 8) & 0xFF);
338 	ahc_outb(ahc, port+2, ((value) >> 16) & 0xFF);
339 	ahc_outb(ahc, port+3, ((value) >> 24) & 0xFF);
340 }
341 
342 /*
343  * Get a free scb. If there are none, see if we can allocate a new SCB.
344  */
345 IO_INLINE struct scb *
346 ahc_get_scb(struct ahc_softc *ahc)
347 {
348 	struct scb *scb;
349 
350 	scb = SLIST_FIRST(&ahc->scb_data->free_scbs);
351 
352 	if (scb != NULL)
353 		SLIST_REMOVE_HEAD(&ahc->scb_data->free_scbs, links.sle);
354 
355 	return (scb);
356 }
357 
358 /*
359  * Return an SCB resource to the free list.
360  */
361 IO_INLINE void
362 ahc_free_scb(struct ahc_softc *ahc, struct scb *scb)
363 {
364 	struct hardware_scb *hscb;
365 
366 	hscb = scb->hscb;
367 	/* Clean up for the next user */
368 	ahc->scb_data->scbindex[hscb->tag] = NULL;
369 	scb->flags = SCB_FLAG_NONE;
370 	hscb->control = 0;
371 
372 	SLIST_INSERT_HEAD(&ahc->scb_data->free_scbs, scb, links.sle);
373 
374 	/* Notify the OSM that a resource is now available. */
375 	ahc_platform_scb_free(ahc, scb);
376 }
377 
378 
379 IO_INLINE struct scb *
380 ahc_lookup_scb(struct ahc_softc *ahc, u_int tag)
381 {
382 	struct scb* scb;
383 
384 	scb = ahc->scb_data->scbindex[tag];
385 	if (scb != NULL)
386 		ahc_sync_scb(ahc, scb,
387 			     BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
388 	return (scb);
389 }
390 
391 
392 IO_INLINE void
393 ahc_swap_with_next_hscb(struct ahc_softc *ahc, struct scb *scb)
394 {
395 	struct hardware_scb *q_hscb;
396 	u_int  saved_tag;
397 
398 	/*
399 	 * Our queuing method is a bit tricky.  The card
400 	 * knows in advance which HSCB to download, and we
401 	 * can't disappoint it.  To achieve this, the next
402 	 * SCB to download is saved off in ahc->next_queued_scb.
403 	 * When we are called to queue "an arbitrary scb",
404 	 * we copy the contents of the incoming HSCB to the one
405 	 * the sequencer knows about, swap HSCB pointers and
406 	 * finally assign the SCB to the tag indexed location
407 	 * in the scb_array.  This makes sure that we can still
408 	 * locate the correct SCB by SCB_TAG.
409 	 */
410 	q_hscb = ahc->next_queued_scb->hscb;
411 	saved_tag = q_hscb->tag;
412 	memcpy(q_hscb, scb->hscb, sizeof(*scb->hscb));
413 	if ((scb->flags & SCB_CDB32_PTR) != 0) {
414 		q_hscb->shared_data.cdb_ptr =
415 		    aic_htole32(ahc_hscb_busaddr(ahc, q_hscb->tag)
416 			      + offsetof(struct hardware_scb, cdb32));
417 	}
418 	q_hscb->tag = saved_tag;
419 	q_hscb->next = scb->hscb->tag;
420 
421 	/* Now swap HSCB pointers. */
422 	ahc->next_queued_scb->hscb = scb->hscb;
423 	scb->hscb = q_hscb;
424 
425 	/* Now define the mapping from tag to SCB in the scbindex */
426 	ahc->scb_data->scbindex[scb->hscb->tag] = scb;
427 }
428 
429 /*
430  * Tell the sequencer about a new transaction to execute.
431  */
432 IO_INLINE void
433 ahc_queue_scb(struct ahc_softc *ahc, struct scb *scb)
434 {
435 	ahc_swap_with_next_hscb(ahc, scb);
436 
437 	if (scb->hscb->tag == SCB_LIST_NULL
438 	 || scb->hscb->next == SCB_LIST_NULL)
439 		panic("Attempt to queue invalid SCB tag %x:%x",
440 		      scb->hscb->tag, scb->hscb->next);
441 
442 	/*
443 	 * Setup data "oddness".
444 	 */
445 	scb->hscb->lun &= LID;
446 	if (ahc_get_transfer_length(scb) & 0x1)
447 		scb->hscb->lun |= SCB_XFERLEN_ODD;
448 
449 	/*
450 	 * Keep a history of SCBs we've downloaded in the qinfifo.
451 	 */
452 	ahc->qinfifo[ahc->qinfifonext] = scb->hscb->tag;
453 	ahc_dmamap_sync(ahc, ahc->parent_dmat, ahc->shared_data_dmamap,
454 			/*offset*/ahc->qinfifonext+256, /*len*/1,
455 			BUS_DMASYNC_PREWRITE);
456 	ahc->qinfifonext++;
457 
458 	/*
459 	 * Make sure our data is consistent from the
460 	 * perspective of the adapter.
461 	 */
462 	ahc_sync_scb(ahc, scb, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
463 
464 	/* Tell the adapter about the newly queued SCB */
465 	if ((ahc->features & AHC_QUEUE_REGS) != 0) {
466 		ahc_outb(ahc, HNSCB_QOFF, ahc->qinfifonext);
467 	} else {
468 		if ((ahc->features & AHC_AUTOPAUSE) == 0)
469 			ahc_pause(ahc);
470 		ahc_outb(ahc, KERNEL_QINPOS, ahc->qinfifonext);
471 		if ((ahc->features & AHC_AUTOPAUSE) == 0)
472 			ahc_unpause(ahc);
473 	}
474 }
475 
476 
477 IO_INLINE struct scsi_sense_data *
478 ahc_get_sense_buf(struct ahc_softc *ahc, struct scb *scb)
479 {
480 	int offset;
481 
482 	offset = scb - ahc->scb_data->scbarray;
483 	return (&ahc->scb_data->sense[offset]);
484 }
485 
486 IO_INLINE uint32_t
487 ahc_get_sense_bufaddr(struct ahc_softc *ahc, struct scb *scb)
488 {
489 	int offset;
490 
491 	offset = scb - ahc->scb_data->scbarray;
492 	return (ahc->scb_data->sense_busaddr
493 	      + (offset * sizeof(struct scsi_sense_data)));
494 }
495 #endif /* IO_EXPAND */
496 
497 /************************** Interrupt Processing ******************************/
498 IO_INLINE void	ahc_sync_qoutfifo(struct ahc_softc *ahc, int op);
499 IO_INLINE void	ahc_sync_tqinfifo(struct ahc_softc *ahc, int op);
500 IO_INLINE u_int	ahc_check_cmdcmpltqueues(struct ahc_softc *ahc);
501 IO_INLINE int	ahc_intr(struct ahc_softc *ahc);
502 
503 #ifdef IO_EXPAND
504 IO_INLINE void
505 ahc_sync_qoutfifo(struct ahc_softc *ahc, int op)
506 {
507 	ahc_dmamap_sync(ahc, ahc->parent_dmat, ahc->shared_data_dmamap,
508 			/*offset*/0, /*len*/256, op);
509 }
510 
511 IO_INLINE void
512 ahc_sync_tqinfifo(struct ahc_softc *ahc, int op)
513 {
514 #ifdef AHC_TARGET_MODE
515 	if ((ahc->flags & AHC_TARGETROLE) != 0) {
516 	  ahc_dmamap_sync(ahc, ahc->parent_dmat /*shared_data_dmat*/,
517 				ahc->shared_data_dmamap,
518 				ahc_targetcmd_offset(ahc, 0),
519 				sizeof(struct target_cmd) * AHC_TMODE_CMDS,
520 				op);
521 	}
522 #endif
523 }
524 
525 /*
526  * See if the firmware has posted any completed commands
527  * into our in-core command complete fifos.
528  */
529 #define AHC_RUN_QOUTFIFO 0x1
530 #define AHC_RUN_TQINFIFO 0x2
531 IO_INLINE u_int
532 ahc_check_cmdcmpltqueues(struct ahc_softc *ahc)
533 {
534 	u_int retval;
535 
536 	retval = 0;
537 	ahc_dmamap_sync(ahc, ahc->parent_dmat /*shared_data_dmat*/, ahc->shared_data_dmamap,
538 			/*offset*/ahc->qoutfifonext, /*len*/1,
539 			BUS_DMASYNC_POSTREAD);
540 	if (ahc->qoutfifo[ahc->qoutfifonext] != SCB_LIST_NULL)
541 		retval |= AHC_RUN_QOUTFIFO;
542 #ifdef AHC_TARGET_MODE
543 	if ((ahc->flags & AHC_TARGETROLE) != 0
544 	    && (ahc->flags & AHC_TQINFIFO_BLOCKED) == 0) {
545 	  ahc_dmamap_sync(ahc, ahc->parent_dmat /*shared_data_dmat*/,
546 			  ahc->shared_data_dmamap,
547 			  ahc_targetcmd_offset(ahc, ahc->tqinfifonext),
548 			  /*len*/sizeof(struct target_cmd),
549 			  BUS_DMASYNC_POSTREAD);
550 		if (ahc->targetcmds[ahc->tqinfifonext].cmd_valid != 0)
551 			retval |= AHC_RUN_TQINFIFO;
552 	}
553 #endif
554 	return (retval);
555 }
556 
557 
558 /*
559  * Catch an interrupt from the adapter
560  */
561 IO_INLINE int
562 ahc_intr(struct ahc_softc *ahc)
563 {
564 	u_int	intstat;
565 
566 	if ((ahc->pause & INTEN) == 0) {
567 		/*
568 		 * Our interrupt is not enabled on the chip
569 		 * and may be disabled for re-entrancy reasons,
570 		 * so just return.  This is likely just a shared
571 		 * interrupt.
572 		 */
573 		return (0);
574 	}
575 	/*
576 	 * Instead of directly reading the interrupt status register,
577 	 * infer the cause of the interrupt by checking our in-core
578 	 * completion queues.  This avoids a costly PCI bus read in
579 	 * most cases.
580 	 */
581 	if ((ahc->flags & (AHC_ALL_INTERRUPTS|AHC_EDGE_INTERRUPT)) == 0
582 	    && (ahc_check_cmdcmpltqueues(ahc) != 0))
583                 intstat = CMDCMPLT;
584         else {
585                 intstat = ahc_inb(ahc, INTSTAT);
586         }
587 
588         if (intstat & CMDCMPLT) {
589 		ahc_outb(ahc, CLRINT, CLRCMDINT);
590 
591 		/*
592 		 * Ensure that the chip sees that we've cleared
593 		 * this interrupt before we walk the output fifo.
594 		 * Otherwise, we may, due to posted bus writes,
595 		 * clear the interrupt after we finish the scan,
596 		 * and after the sequencer has added new entries
597 		 * and asserted the interrupt again.
598 		 */
599 		ahc_flush_device_writes(ahc);
600 		ahc_run_qoutfifo(ahc);
601 #ifdef AHC_TARGET_MODE
602 		if ((ahc->flags & AHC_TARGETROLE) != 0)
603 			ahc_run_tqinfifo(ahc, /*paused*/FALSE);
604 #endif
605 	}
606 
607 	if (intstat == 0xFF && (ahc->features & AHC_REMOVABLE) != 0)
608 		/* Hot eject */
609 		return 1;
610 
611 	if ((intstat & INT_PEND) == 0) {
612 #if AHC_PCI_CONFIG > 0
613 		if (ahc->unsolicited_ints > 500) {
614 			ahc->unsolicited_ints = 0;
615 			if ((ahc->chip & AHC_PCI) != 0
616 			 && (ahc_inb(ahc, ERROR) & PCIERRSTAT) != 0)
617 				ahc->bus_intr(ahc);
618 		}
619 		ahc->unsolicited_ints++;
620 #endif
621 		return 0;
622 	}
623 	ahc->unsolicited_ints = 0;
624 
625 	if (intstat & BRKADRINT) {
626 		ahc_handle_brkadrint(ahc);
627 		/* Fatal error, no more interrupts to handle. */
628 		return 1;
629 	}
630 
631 	if ((intstat & (SEQINT|SCSIINT)) != 0)
632 		ahc_pause_bug_fix(ahc);
633 
634 	if ((intstat & SEQINT) != 0)
635 		ahc_handle_seqint(ahc, intstat);
636 
637 	if ((intstat & SCSIINT) != 0)
638 		ahc_handle_scsiint(ahc, intstat);
639 
640 	return (1);
641 }
642 
643 #endif	/* IO_EXPAND */
644 
645 #endif  /* _AIC7XXX_INLINE_H_ */
646