xref: /netbsd-src/sys/dev/isa/seagate.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: seagate.c,v 1.59 2005/12/11 12:22:03 christos Exp $	*/
2 
3 /*
4  * ST01/02, Future Domain TMC-885, TMC-950 SCSI driver
5  *
6  * Copyright 1994, Charles M. Hannum (mycroft@ai.mit.edu)
7  * Copyright 1994, Kent Palmkvist (kentp@isy.liu.se)
8  * Copyright 1994, Robert Knier (rknier@qgraph.com)
9  * Copyright 1992, 1994 Drew Eckhardt (drew@colorado.edu)
10  * Copyright 1994, Julian Elischer (julian@tfs.com)
11  *
12  * Others that has contributed by example code is
13  * 		Glen Overby (overby@cray.com)
14  *		Tatu Yllnen
15  *		Brian E Litzinger
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE DEVELOPERS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 /*
40  * kentp  940307 alpha version based on newscsi-03 version of Julians SCSI-code
41  * kentp  940314 Added possibility to not use messages
42  * rknier 940331 Added fast transfer code
43  * rknier 940407 Added assembler coded data transfers
44  */
45 
46 /*
47  * What should really be done:
48  *
49  * Add missing tests for timeouts
50  * Restructure interrupt enable/disable code (runs to long with int disabled)
51  * Find bug? giving problem with tape status
52  * Add code to handle Future Domain 840, 841, 880 and 881
53  * adjust timeouts (startup is very slow)
54  * add code to use tagged commands in SCSI2
55  * Add code to handle slow devices better (sleep if device not disconnecting)
56  * Fix unnecessary interrupts
57  */
58 
59 /*
60  * Note to users trying to share a disk between DOS and unix:
61  * The ST01/02 is a translating host-adapter. It is not giving DOS
62  * the same number of heads/tracks/sectors as specified by the disk.
63  * It is therefore important to look at what numbers DOS thinks the
64  * disk has. Use these to disklabel your disk in an appropriate manner
65  */
66 
67 #include <sys/cdefs.h>
68 __KERNEL_RCSID(0, "$NetBSD: seagate.c,v 1.59 2005/12/11 12:22:03 christos Exp $");
69 
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/kernel.h>
73 #include <sys/errno.h>
74 #include <sys/ioctl.h>
75 #include <sys/device.h>
76 #include <sys/buf.h>
77 #include <sys/proc.h>
78 #include <sys/user.h>
79 #include <sys/queue.h>
80 #include <sys/malloc.h>
81 
82 #include <machine/intr.h>
83 #include <machine/pio.h>
84 
85 #include <dev/scsipi/scsi_all.h>
86 #include <dev/scsipi/scsipi_all.h>
87 #include <dev/scsipi/scsi_message.h>
88 #include <dev/scsipi/scsiconf.h>
89 
90 #include <dev/isa/isareg.h>
91 #include <dev/isa/isavar.h>	/* XXX USES ISA HOLE DIRECTLY */
92 
93 #define	SEA_SCB_MAX	32	/* allow maximally 8 scsi control blocks */
94 #define SCB_TABLE_SIZE	8	/* start with 8 scb entries in table */
95 #define BLOCK_SIZE	512	/* size of READ/WRITE areas on SCSI card */
96 
97 /*
98  * defining SEA_BLINDTRANSFER will make DATA IN and DATA OUT to be done with
99  * blind transfers, i.e. no check is done for scsi phase changes. This will
100  * result in data loss if the scsi device does not send its data using
101  * BLOCK_SIZE bytes at a time.
102  * If SEA_BLINDTRANSFER defined and SEA_ASSEMBLER also defined will result in
103  * the use of blind transfers coded in assembler. SEA_ASSEMBLER is no good
104  * without SEA_BLINDTRANSFER defined.
105  */
106 #define	SEA_BLINDTRANSFER	/* do blind transfers */
107 #define	SEA_ASSEMBLER		/* Use assembly code for fast transfers */
108 
109 /*
110  * defining SEA_NOMSGS causes messages not to be used (thereby disabling
111  * disconnects)
112  */
113 #undef	SEA_NOMSGS
114 
115 /*
116  * defining SEA_NODATAOUT makes dataout phase being aborted
117  */
118 #undef	SEA_NODATAOUT
119 
120 /* Debugging definitions. Should not be used unless you want a lot of
121    printouts even under normal conditions */
122 
123 #undef	SEA_DEBUGQUEUE		/* Display info about queue-lengths */
124 
125 /******************************* board definitions **************************/
126 /*
127  * CONTROL defines
128  */
129 #define CMD_RST		0x01		/* scsi reset */
130 #define CMD_SEL		0x02		/* scsi select */
131 #define CMD_BSY		0x04		/* scsi busy */
132 #define	CMD_ATTN	0x08		/* scsi attention */
133 #define CMD_START_ARB	0x10		/* start arbitration bit */
134 #define	CMD_EN_PARITY	0x20		/* enable scsi parity generation */
135 #define CMD_INTR	0x40		/* enable scsi interrupts */
136 #define CMD_DRVR_ENABLE	0x80		/* scsi enable */
137 
138 /*
139  * STATUS
140  */
141 #define STAT_BSY	0x01		/* scsi busy */
142 #define STAT_MSG	0x02		/* scsi msg */
143 #define STAT_IO		0x04		/* scsi I/O */
144 #define STAT_CD		0x08		/* scsi C/D */
145 #define STAT_REQ	0x10		/* scsi req */
146 #define STAT_SEL	0x20		/* scsi select */
147 #define STAT_PARITY	0x40		/* parity error bit */
148 #define STAT_ARB_CMPL	0x80		/* arbitration complete bit */
149 
150 /*
151  * REQUESTS
152  */
153 #define PH_DATAOUT	(0)
154 #define PH_DATAIN	(STAT_IO)
155 #define PH_CMD		(STAT_CD)
156 #define PH_STAT		(STAT_CD | STAT_IO)
157 #define PH_MSGOUT	(STAT_MSG | STAT_CD)
158 #define PH_MSGIN	(STAT_MSG | STAT_CD | STAT_IO)
159 
160 #define PH_MASK		(STAT_MSG | STAT_CD | STAT_IO)
161 
162 #define PH_INVALID	0xff
163 
164 #define SEA_RAMOFFSET	0x00001800
165 
166 #define BASE_CMD	(CMD_INTR | CMD_EN_PARITY)
167 
168 #define	SEAGATE		1	/* Seagate ST0[12] */
169 #define	FDOMAIN		2	/* Future Domain TMC-{885,950} */
170 #define	FDOMAIN840	3	/* Future Domain TMC-{84[01],88[01]} */
171 
172 /******************************************************************************/
173 
174 /* scsi control block used to keep info about a scsi command */
175 struct sea_scb {
176         u_char *data;			/* position in data buffer so far */
177 	int datalen;			/* bytes remaining to transfer */
178 	TAILQ_ENTRY(sea_scb) chain;
179 	struct scsipi_xfer *xs;		/* the scsipi_xfer for this cmd */
180 	int flags;			/* status of the instruction */
181 #define	SCB_FREE	0
182 #define	SCB_ACTIVE	1
183 #define SCB_ABORTED	2
184 #define SCB_TIMEOUT	4
185 #define SCB_ERROR	8
186 };
187 
188 /*
189  * data structure describing current status of the scsi bus. One for each
190  * controller card.
191  */
192 struct sea_softc {
193 	struct device sc_dev;
194 	void *sc_ih;
195 
196 	int type;			/* board type */
197 	caddr_t	maddr;			/* Base address for card */
198 	caddr_t	maddr_cr_sr;		/* Address of control and status reg */
199 	caddr_t	maddr_dr;		/* Address of data register */
200 
201 	struct scsipi_adapter sc_adapter;
202 	struct scsipi_channel sc_channel;
203 
204 	TAILQ_HEAD(, sea_scb) free_list, ready_list, nexus_list;
205 	struct sea_scb *nexus;		/* currently connected command */
206 	int numscbs;			/* number of scsi control blocks */
207 	struct sea_scb scb[SCB_TABLE_SIZE];
208 
209 	int our_id;			/* our scsi id */
210 	u_char our_id_mask;
211 	volatile u_char busy[8];	/* index=target, bit=lun, Keep track of
212 					   busy luns at device target */
213 };
214 
215 /* flag showing if main routine is running. */
216 static volatile int main_running = 0;
217 
218 #define	STATUS	(*(volatile u_char *)sea->maddr_cr_sr)
219 #define CONTROL	STATUS
220 #define DATA	(*(volatile u_char *)sea->maddr_dr)
221 
222 /*
223  * These are "special" values for the tag parameter passed to sea_select
224  * Not implemented right now.
225  */
226 #define TAG_NEXT	-1	/* Use next free tag */
227 #define TAG_NONE	-2	/*
228 				 * Establish I_T_L nexus instead of I_T_L_Q
229 				 * even on SCSI-II devices.
230 				 */
231 
232 typedef struct {
233 	const char *signature;
234 	int offset, length;
235 	int type;
236 } BiosSignature;
237 
238 /*
239  * Signatures for automatic recognition of board type
240  */
241 static const BiosSignature signatures[] = {
242 {"ST01 v1.7  (C) Copyright 1987 Seagate", 15, 37, SEAGATE},
243 {"SCSI BIOS 2.00  (C) Copyright 1987 Seagate", 15, 40, SEAGATE},
244 
245 /*
246  * The following two lines are NOT mistakes. One detects ROM revision
247  * 3.0.0, the other 3.2. Since seagate has only one type of SCSI adapter,
248  * and this is not going to change, the "SEAGATE" and "SCSI" together
249  * are probably "good enough"
250  */
251 {"SEAGATE SCSI BIOS ", 16, 17, SEAGATE},
252 {"SEAGATE SCSI BIOS ", 17, 17, SEAGATE},
253 
254 /*
255  * However, future domain makes several incompatible SCSI boards, so specific
256  * signatures must be used.
257  */
258 {"FUTURE DOMAIN CORP. (C) 1986-1989 V5.0C2/14/89", 5, 45, FDOMAIN},
259 {"FUTURE DOMAIN CORP. (C) 1986-1989 V6.0A7/28/89", 5, 46, FDOMAIN},
260 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0105/31/90",5, 47, FDOMAIN},
261 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0209/18/90",5, 47, FDOMAIN},
262 {"FUTURE DOMAIN CORP. (C) 1986-1990 V7.009/18/90", 5, 46, FDOMAIN},
263 {"FUTURE DOMAIN CORP. (C) 1992 V8.00.004/02/92",   5, 44, FDOMAIN},
264 {"FUTURE DOMAIN TMC-950",			   5, 21, FDOMAIN},
265 };
266 
267 #define	nsignatures	(sizeof(signatures) / sizeof(signatures[0]))
268 
269 #ifdef notdef
270 static const char *bases[] = {
271 	(char *) 0xc8000, (char *) 0xca000, (char *) 0xcc000,
272 	(char *) 0xce000, (char *) 0xdc000, (char *) 0xde000
273 };
274 
275 #define	nbases		(sizeof(bases) / sizeof(bases[0]))
276 #endif
277 
278 int seaintr(void *);
279 void sea_scsipi_request(struct scsipi_channel *, scsipi_adapter_req_t, void *);
280 void sea_timeout(void *);
281 void sea_done(struct sea_softc *, struct sea_scb *);
282 struct sea_scb *sea_get_scb(struct sea_softc *, int);
283 void sea_free_scb(struct sea_softc *, struct sea_scb *, int);
284 static void sea_main(void);
285 static void sea_information_transfer(struct sea_softc *);
286 int sea_poll(struct sea_softc *, struct scsipi_xfer *, int);
287 void sea_init(struct sea_softc *);
288 void sea_send_scb(struct sea_softc *sea, struct sea_scb *scb);
289 void sea_reselect(struct sea_softc *sea);
290 int sea_select(struct sea_softc *sea, struct sea_scb *scb);
291 int sea_transfer_pio(struct sea_softc *sea, u_char *phase,
292     int *count, u_char **data);
293 int sea_abort(struct sea_softc *, struct sea_scb *scb);
294 
295 void	sea_grow_scb(struct sea_softc *);
296 
297 int	seaprobe(struct device *, struct cfdata *, void *);
298 void	seaattach(struct device *, struct device *, void *);
299 
300 CFATTACH_DECL(sea, sizeof(struct sea_softc),
301     seaprobe, seaattach, NULL, NULL);
302 
303 extern struct cfdriver sea_cd;
304 
305 #ifdef SEA_DEBUGQUEUE
306 void
307 sea_queue_length(sea)
308 	struct sea_softc *sea;
309 {
310 	struct sea_scb *scb;
311 	int connected, issued, disconnected;
312 
313 	connected = sea->nexus ? 1 : 0;
314 	for (scb = sea->ready_list.tqh_first, issued = 0; scb;
315 	    scb = scb->chain.tqe_next, issued++);
316 	for (scb = sea->nexus_list.tqh_first, disconnected = 0; scb;
317 	    scb = scb->chain.tqe_next, disconnected++);
318 	printf("%s: length: %d/%d/%d\n", sea->sc_dev.dv_xname, connected,
319 	    issued, disconnected);
320 }
321 #endif
322 
323 /*
324  * Check if the device can be found at the port given and if so, detect the
325  * type the type of board.  Set it up ready for further work. Takes the isa_dev
326  * structure from autoconf as an argument.
327  * Returns 1 if card recognized, 0 if errors.
328  */
329 int
330 seaprobe(parent, match, aux)
331 	struct device *parent;
332 	struct cfdata *match;
333 	void *aux;
334 {
335 	struct isa_attach_args *ia = aux;
336 	int i, type = 0;
337 	caddr_t maddr;
338 
339 	if (ia->ia_niomem < 1)
340 		return (0);
341 	if (ia->ia_nirq < 1)
342 		return (0);
343 
344 	if (ISA_DIRECT_CONFIG(ia))
345 		return (0);
346 
347 	if (ia->ia_iomem[0].ir_addr == ISA_UNKNOWN_IOMEM)
348 		return (0);
349 	if (ia->ia_irq[0].ir_irq == ISA_UNKNOWN_IRQ)
350 		return (0);
351 
352 	/* XXX XXX XXX */
353 	maddr = ISA_HOLE_VADDR(ia->ia_iomem[0].ir_addr);
354 
355 	/* check board type */	/* No way to define this through config */
356 	for (i = 0; i < nsignatures; i++)
357 		if (!memcmp(maddr + signatures[i].offset,
358 		    signatures[i].signature, signatures[i].length)) {
359 			type = signatures[i].type;
360 			break;
361 		}
362 
363 	/* Find controller and data memory addresses */
364 	switch (type) {
365 	case SEAGATE:
366 	case FDOMAIN840:
367 	case FDOMAIN:
368 		break;
369 	default:
370 #ifdef SEA_DEBUG
371 		printf("seaprobe: board type unknown at address %p\n", maddr);
372 #endif
373 		return 0;
374 	}
375 
376 	ia->ia_niomem = 1;
377 	ia->ia_iomem[0].ir_size = 0x2000;
378 
379 	ia->ia_nirq = 1;
380 
381 	ia->ia_nio = 0;
382 	ia->ia_ndrq = 0;
383 
384 	return 1;
385 }
386 
387 /*
388  * Attach all sub-devices we can find
389  */
390 void
391 seaattach(parent, self, aux)
392 	struct device *parent, *self;
393 	void *aux;
394 {
395 	struct isa_attach_args *ia = aux;
396 	struct sea_softc *sea = (void *)self;
397 	struct scsipi_adapter *adapt = &sea->sc_adapter;
398 	struct scsipi_channel *chan = &sea->sc_channel;
399 	int i;
400 
401 	/* XXX XXX XXX */
402 	sea->maddr = ISA_HOLE_VADDR(ia->ia_iomem[0].ir_addr);
403 
404 	/* check board type */	/* No way to define this through config */
405 	for (i = 0; i < nsignatures; i++)
406 		if (!memcmp(sea->maddr + signatures[i].offset,
407 		    signatures[i].signature, signatures[i].length)) {
408 			sea->type = signatures[i].type;
409 			break;
410 		}
411 
412 	/* Find controller and data memory addresses */
413 	switch (sea->type) {
414 	case SEAGATE:
415 	case FDOMAIN840:
416 		sea->maddr_cr_sr =
417 		    (void *) (((u_char *)sea->maddr) + 0x1a00);
418 		sea->maddr_dr =
419 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
420 		break;
421 	case FDOMAIN:
422 		sea->maddr_cr_sr =
423 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
424 		sea->maddr_dr =
425 		    (void *) (((u_char *)sea->maddr) + 0x1e00);
426 		break;
427 	default:
428 #ifdef DEBUG
429 		printf("%s: board type unknown at address %p\n",
430 		    sea->sc_dev.dv_xname, sea->maddr);
431 #endif
432 		return;
433 	}
434 
435 	/* Test controller RAM (works the same way on future domain cards?) */
436 	*((u_char *)sea->maddr + SEA_RAMOFFSET) = 0xa5;
437 	*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) = 0x5a;
438 
439 	if ((*((u_char *)sea->maddr + SEA_RAMOFFSET) != 0xa5) ||
440 	    (*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) != 0x5a)) {
441 		printf("%s: board RAM failure\n", sea->sc_dev.dv_xname);
442 		return;
443 	}
444 
445 	sea_init(sea);
446 
447 	/*
448 	 * Fill in the scsipi_adapter.
449 	 */
450 	memset(adapt, 0, sizeof(*adapt));
451 	adapt->adapt_dev = &sea->sc_dev;
452 	adapt->adapt_nchannels = 1;
453 	adapt->adapt_openings = sea->numscbs;
454 	adapt->adapt_max_periph = 1;
455 	adapt->adapt_request = sea_scsipi_request;
456 	adapt->adapt_minphys = minphys;
457 
458 	/*
459 	 * Fill in the scsipi_channel.
460 	 */
461 	memset(chan, 0, sizeof(*chan));
462 	chan->chan_adapter = adapt;
463 	chan->chan_bustype = &scsi_bustype;
464 	chan->chan_channel = 0;
465 	chan->chan_ntargets = 8;
466 	chan->chan_nluns = 8;
467 	chan->chan_id = sea->our_id;
468 	chan->chan_flags = SCSIPI_CHAN_CANGROW;
469 
470 	printf("\n");
471 
472 	sea->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq[0].ir_irq,
473 	    IST_EDGE, IPL_BIO, seaintr, sea);
474 
475 	/*
476 	 * ask the adapter what subunits are present
477 	 */
478 	config_found(self, &sea->sc_channel, scsiprint);
479 }
480 
481 /*
482  * Catch an interrupt from the adaptor
483  */
484 int
485 seaintr(arg)
486 	void *arg;
487 {
488 	struct sea_softc *sea = arg;
489 
490 #ifdef DEBUG	/* extra overhead, and only needed for intr debugging */
491 	if ((STATUS & STAT_PARITY) == 0 &&
492 	    (STATUS & (STAT_SEL | STAT_IO)) != (STAT_SEL | STAT_IO))
493 		return 0;
494 #endif
495 
496 loop:
497 	/* dispatch to appropriate routine if found and done=0 */
498 	/* should check to see that this card really caused the interrupt */
499 
500 	if (STATUS & STAT_PARITY) {
501 		/* Parity error interrupt */
502 		printf("%s: parity error\n", sea->sc_dev.dv_xname);
503 		return 1;
504 	}
505 
506 	if ((STATUS & (STAT_SEL | STAT_IO)) == (STAT_SEL | STAT_IO)) {
507 		/* Reselect interrupt */
508 		sea_reselect(sea);
509 		if (!main_running)
510 			sea_main();
511 		goto loop;
512 	}
513 
514 	return 1;
515 }
516 
517 /*
518  * Setup data structures, and reset the board and the SCSI bus.
519  */
520 void
521 sea_init(sea)
522 	struct sea_softc *sea;
523 {
524 	int i;
525 
526 	/* Reset the scsi bus (I don't know if this is needed */
527 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_RST;
528 	delay(25);	/* hold reset for at least 25 microseconds */
529 	CONTROL = BASE_CMD;
530 	delay(10); 	/* wait a Bus Clear Delay (800 ns + bus free delay (800 ns) */
531 
532 	/* Set our id (don't know anything about this) */
533 	switch (sea->type) {
534 	case SEAGATE:
535 		sea->our_id = 7;
536 		break;
537 	case FDOMAIN:
538 	case FDOMAIN840:
539 		sea->our_id = 6;
540 		break;
541 	}
542 	sea->our_id_mask = 1 << sea->our_id;
543 
544 	/* init fields used by our routines */
545 	sea->nexus = 0;
546 	TAILQ_INIT(&sea->ready_list);
547 	TAILQ_INIT(&sea->nexus_list);
548 	TAILQ_INIT(&sea->free_list);
549 	for (i = 0; i < 8; i++)
550 		sea->busy[i] = 0x00;
551 
552 	/* link up the free list of scbs */
553 	sea->numscbs = SCB_TABLE_SIZE;
554 	for (i = 0; i < SCB_TABLE_SIZE; i++) {
555 		TAILQ_INSERT_TAIL(&sea->free_list, &sea->scb[i], chain);
556 	}
557 }
558 
559 /*
560  * start a scsi operation given the command and the data address. Also needs
561  * the unit, target and lu.
562  */
563 void
564 sea_scsipi_request(chan, req, arg)
565 	struct scsipi_channel *chan;
566 	scsipi_adapter_req_t req;
567 	void *arg;
568 {
569 	struct scsipi_xfer *xs;
570 	struct scsipi_periph *periph;
571 	struct sea_softc *sea = (void *)chan->chan_adapter->adapt_dev;
572 	struct sea_scb *scb;
573 	int flags;
574 	int s;
575 
576 	switch (req) {
577 	case ADAPTER_REQ_RUN_XFER:
578 		xs = arg;
579 		periph = xs->xs_periph;
580 		flags = xs->xs_control;
581 
582 		SC_DEBUG(periph, SCSIPI_DB2, ("sea_scsipi_requeset\n"));
583 
584 		/* XXX Reset not implemented. */
585 		if (flags & XS_CTL_RESET) {
586 			printf("%s: resetting\n", sea->sc_dev.dv_xname);
587 			xs->error = XS_DRIVER_STUFFUP;
588 			scsipi_done(xs);
589 			return;
590 		}
591 
592 		/* Get an SCB to use. */
593 		scb = sea_get_scb(sea, flags);
594 #ifdef DIAGNOSTIC
595 		/*
596 		 * This should never happen as we track the resources
597 		 * in the mid-layer.
598 		 */
599 		if (scb == NULL) {
600 			scsipi_printaddr(periph);
601 			printf("unable to allocate scb\n");
602 			panic("sea_scsipi_request");
603 		}
604 #endif
605 
606 		scb->flags = SCB_ACTIVE;
607 		scb->xs = xs;
608 
609 		/*
610 		 * Put all the arguments for the xfer in the scb
611 		 */
612 		scb->datalen = xs->datalen;
613 		scb->data = xs->data;
614 
615 #ifdef SEA_DEBUGQUEUE
616 		sea_queue_length(sea);
617 #endif
618 
619 		s = splbio();
620 
621 		sea_send_scb(sea, scb);
622 
623 		if ((flags & XS_CTL_POLL) == 0) {
624 			callout_reset(&scb->xs->xs_callout,
625 			    mstohz(xs->timeout), sea_timeout, scb);
626 			splx(s);
627 			return;
628 		}
629 
630 		splx(s);
631 
632 		/*
633 		 * If we can't use interrupts, poll on completion
634 		 */
635 		if (sea_poll(sea, xs, xs->timeout)) {
636 			sea_timeout(scb);
637 			if (sea_poll(sea, xs, 2000))
638 				sea_timeout(scb);
639 		}
640 		return;
641 
642 	case ADAPTER_REQ_GROW_RESOURCES:
643 		sea_grow_scb(sea);
644 		return;
645 
646 	case ADAPTER_REQ_SET_XFER_MODE:
647 	    {
648 		struct scsipi_xfer_mode *xm = arg;
649 
650 		/*
651 		 * We don't support sync or wide or tagged queueing,
652 		 * so announce that now.
653 		 */
654 		xm->xm_mode = 0;
655 		xm->xm_period = 0;
656 		xm->xm_offset = 0;
657 		scsipi_async_event(chan, ASYNC_EVENT_XFER_MODE, xm);
658 		return;
659 	    }
660 	}
661 }
662 
663 /*
664  * Get a free scb. If there are none, see if we can allocate a new one.  If so,
665  * put it in the hash table too; otherwise return an error or sleep.
666  */
667 struct sea_scb *
668 sea_get_scb(sea, flags)
669 	struct sea_softc *sea;
670 	int flags;
671 {
672 	int s;
673 	struct sea_scb *scb;
674 
675 	s = splbio();
676 	if ((scb = TAILQ_FIRST(&sea->free_list)) != NULL)
677 		TAILQ_REMOVE(&sea->free_list, scb, chain);
678 	splx(s);
679 
680 	return (scb);
681 }
682 
683 /*
684  * Try to send this command to the board. Because this board does not use any
685  * mailboxes, this routine simply adds the command to the queue held by the
686  * sea_softc structure.
687  * A check is done to see if the command contains a REQUEST_SENSE command, and
688  * if so the command is put first in the queue, otherwise the command is added
689  * to the end of the queue. ?? Not correct ??
690  */
691 void
692 sea_send_scb(sea, scb)
693 	struct sea_softc *sea;
694 	struct sea_scb *scb;
695 {
696 
697 	TAILQ_INSERT_TAIL(&sea->ready_list, scb, chain);
698 	/* Try to do some work on the card. */
699 	if (!main_running)
700 		sea_main();
701 }
702 
703 /*
704  * Coroutine that runs as long as more work can be done on the seagate host
705  * adapter in a system.  Both sea_scsi_cmd and sea_intr will try to start it in
706  * case it is not running.
707  */
708 
709 void
710 sea_main()
711 {
712 	struct sea_softc *sea;
713 	struct sea_scb *scb;
714 	int done;
715 	int unit;
716 	int s;
717 
718 	main_running = 1;
719 
720 	/*
721 	 * This should not be run with interrupts disabled, but use the splx
722 	 * code instead.
723 	 */
724 loop:
725 	done = 1;
726 	for (unit = 0; unit < sea_cd.cd_ndevs; unit++) {
727 		sea = device_lookup(&sea_cd, unit);
728 		if (!sea)
729 			continue;
730 		s = splbio();
731 		if (!sea->nexus) {
732 			/*
733 			 * Search through the ready_list for a command
734 			 * destined for a target that's not busy.
735 			 */
736 			for (scb = sea->ready_list.tqh_first; scb;
737 			    scb = scb->chain.tqe_next) {
738 				if (!(sea->busy[scb->xs->xs_periph->periph_target] &
739 				    (1 << scb->xs->xs_periph->periph_lun))) {
740 					TAILQ_REMOVE(&sea->ready_list, scb,
741 					    chain);
742 
743 					/* Re-enable interrupts. */
744 					splx(s);
745 
746 					/*
747 					 * Attempt to establish an I_T_L nexus.
748 					 * On success, sea->nexus is set.
749 					 * On failure, we must add the command
750 					 * back to the issue queue so we can
751 					 * keep trying.
752 					 */
753 
754 					/*
755 					 * REQUEST_SENSE commands are issued
756 					 * without tagged queueing, even on
757 					 * SCSI-II devices because the
758 					 * contingent alligence condition
759 					 * exists for the entire unit.
760 					 */
761 
762 					/*
763 					 * First check that if any device has
764 					 * tried a reconnect while we have done
765 					 * other things with interrupts
766 					 * disabled.
767 					 */
768 
769 					if ((STATUS & (STAT_SEL | STAT_IO)) ==
770 					    (STAT_SEL | STAT_IO)) {
771 						sea_reselect(sea);
772 						break;
773 					}
774 					if (sea_select(sea, scb)) {
775 						s = splbio();
776 						TAILQ_INSERT_HEAD(&sea->ready_list,
777 						    scb, chain);
778 						splx(s);
779 					} else
780 						break;
781 				} /* if target/lun is not busy */
782 			} /* for scb */
783 			if (!sea->nexus) {
784 				/* check for reselection phase */
785 				if ((STATUS & (STAT_SEL | STAT_IO)) ==
786 				    (STAT_SEL | STAT_IO)) {
787 					sea_reselect(sea);
788 				}
789 			}
790 		} /* if (!sea->nexus) */
791 
792 		splx(s);
793 		if (sea->nexus) {	/* we are connected. Do the task */
794 			sea_information_transfer(sea);
795 			done = 0;
796 		} else
797 			break;
798 	} /* for instance */
799 
800 	if (!done)
801 		goto loop;
802 
803 	main_running = 0;
804 }
805 
806 /*
807  * Allocate an scb and add it to the free list.
808  * We are called at splbio.
809  */
810 void
811 sea_grow_scb(sea)
812 	struct sea_softc *sea;
813 {
814 	struct sea_scb *scb;
815 
816 	if (sea->numscbs == SEA_SCB_MAX) {
817 		sea->sc_channel.chan_flags &= ~SCSIPI_CHAN_CANGROW;
818 		return;
819 	}
820 
821 	scb = malloc(sizeof(struct sea_scb), M_DEVBUF, M_NOWAIT|M_ZERO);
822 	if (scb == NULL)
823 		return;
824 
825 	TAILQ_INSERT_TAIL(&sea->free_list, scb, chain);
826 	sea->numscbs++;
827 	sea->sc_adapter.adapt_openings++;
828 }
829 void
830 sea_free_scb(sea, scb, flags)
831 	struct sea_softc *sea;
832 	struct sea_scb *scb;
833 	int flags;
834 {
835 	int s;
836 
837 	s = splbio();
838 	scb->flags = SCB_FREE;
839 	TAILQ_INSERT_HEAD(&sea->free_list, scb, chain);
840 	splx(s);
841 }
842 
843 void
844 sea_timeout(arg)
845 	void *arg;
846 {
847 	struct sea_scb *scb = arg;
848 	struct scsipi_xfer *xs = scb->xs;
849 	struct scsipi_periph *periph = xs->xs_periph;
850 	struct sea_softc *sea =
851 	    (void *)periph->periph_channel->chan_adapter->adapt_dev;
852 	int s;
853 
854 	scsipi_printaddr(periph);
855 	printf("timed out");
856 
857 	s = splbio();
858 
859 	/*
860 	 * If it has been through before, then
861 	 * a previous abort has failed, don't
862 	 * try abort again
863 	 */
864 	if (scb->flags & SCB_ABORTED) {
865 		/* abort timed out */
866 		printf(" AGAIN\n");
867 	 	scb->xs->xs_retries = 0;
868 		scb->flags |= SCB_ABORTED;
869 		sea_done(sea, scb);
870 	} else {
871 		/* abort the operation that has timed out */
872 		printf("\n");
873 		scb->flags |= SCB_ABORTED;
874 		sea_abort(sea, scb);
875 		/* 2 secs for the abort */
876 		if ((xs->xs_control & XS_CTL_POLL) == 0)
877 			callout_reset(&scb->xs->xs_callout, 2 * hz,
878 			    sea_timeout, scb);
879 	}
880 
881 	splx(s);
882 }
883 
884 void
885 sea_reselect(sea)
886 	struct sea_softc *sea;
887 {
888 	u_char target_mask;
889 	int i;
890 	u_char lun, phase;
891 	u_char msg[3];
892 	int len;
893 	u_char *data;
894 	struct sea_scb *scb;
895 	int abort = 0;
896 
897 	if (!((target_mask = STATUS) & STAT_SEL)) {
898 		printf("%s: wrong state 0x%x\n", sea->sc_dev.dv_xname,
899 		    target_mask);
900 		return;
901 	}
902 
903 	/* wait for a device to win the reselection phase */
904 	/* signals this by asserting the I/O signal */
905 	for (i = 10; i && (STATUS & (STAT_SEL | STAT_IO | STAT_BSY)) !=
906 	    (STAT_SEL | STAT_IO | 0); i--);
907 	/* !! Check for timeout here */
908 	/* the data bus contains original initiator id ORed with target id */
909 	target_mask = DATA;
910 	/* see that we really are the initiator */
911 	if (!(target_mask & sea->our_id_mask)) {
912 		printf("%s: polled reselection was not for me: 0x%x\n",
913 		    sea->sc_dev.dv_xname, target_mask);
914 		return;
915 	}
916 	/* find target who won */
917 	target_mask &= ~sea->our_id_mask;
918 	/* host responds by asserting the BSY signal */
919 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY;
920 	/* target should respond by deasserting the SEL signal */
921 	for (i = 50000; i && (STATUS & STAT_SEL); i++);
922 	/* remove the busy status */
923 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
924 	/* we are connected. Now we wait for the MSGIN condition */
925 	for (i = 50000; i && !(STATUS & STAT_REQ); i--);
926 	/* !! Add timeout check here */
927 	/* hope we get an IDENTIFY message */
928 	len = 3;
929 	data = msg;
930 	phase = PH_MSGIN;
931 	sea_transfer_pio(sea, &phase, &len, &data);
932 
933 	if (!MSG_ISIDENTIFY(msg[0])) {
934 		printf("%s: expecting IDENTIFY message, got 0x%x\n",
935 		    sea->sc_dev.dv_xname, msg[0]);
936 		abort = 1;
937 		scb = NULL;
938 	} else {
939 		lun = msg[0] & 0x07;
940 
941 		/*
942 		 * Find the command corresponding to the I_T_L or I_T_L_Q nexus
943 		 * we just reestablished, and remove it from the disconnected
944 		 * queue.
945 		 */
946 		for (scb = sea->nexus_list.tqh_first; scb;
947 		    scb = scb->chain.tqe_next)
948 			if (target_mask == (1 << scb->xs->xs_periph->periph_target) &&
949 			    lun == scb->xs->xs_periph->periph_lun) {
950 				TAILQ_REMOVE(&sea->nexus_list, scb,
951 				    chain);
952 				break;
953 			}
954 		if (!scb) {
955 			printf("%s: target %02x lun %d not disconnected\n",
956 			    sea->sc_dev.dv_xname, target_mask, lun);
957 			/*
958 			 * Since we have an established nexus that we can't do
959 			 * anything with, we must abort it.
960 			 */
961 			abort = 1;
962 		}
963 	}
964 
965 	if (abort) {
966 		msg[0] = MSG_ABORT;
967 		len = 1;
968 		data = msg;
969 		phase = PH_MSGOUT;
970 		CONTROL = BASE_CMD | CMD_ATTN;
971 		sea_transfer_pio(sea, &phase, &len, &data);
972 	} else
973 		sea->nexus = scb;
974 
975 	return;
976 }
977 
978 /*
979  * Transfer data in given phase using polled I/O.
980  */
981 int
982 sea_transfer_pio(sea, phase, count, data)
983 	struct sea_softc *sea;
984 	u_char *phase;
985 	int *count;
986 	u_char **data;
987 {
988 	u_char p = *phase, tmp;
989 	int c = *count;
990 	u_char *d = *data;
991 	int timeout;
992 
993 	do {
994 		/*
995 		 * Wait for assertion of REQ, after which the phase bits will
996 		 * be valid.
997 		 */
998 		for (timeout = 0; timeout < 50000; timeout++)
999 			if ((tmp = STATUS) & STAT_REQ)
1000 				break;
1001 		if (!(tmp & STAT_REQ)) {
1002 			printf("%s: timeout waiting for STAT_REQ\n",
1003 			    sea->sc_dev.dv_xname);
1004 			break;
1005 		}
1006 
1007 		/*
1008 		 * Check for phase mismatch.  Reached if the target decides
1009 		 * that it has finished the transfer.
1010 		 */
1011 		if (sea->type == FDOMAIN840)
1012 			tmp = ((tmp & 0x08) >> 2) |
1013 			      ((tmp & 0x02) << 2) |
1014 			       (tmp & 0xf5);
1015 		if ((tmp & PH_MASK) != p)
1016 			break;
1017 
1018 		/* Do actual transfer from SCSI bus to/from memory. */
1019 		if (!(p & STAT_IO))
1020 			DATA = *d;
1021 		else
1022 			*d = DATA;
1023 		++d;
1024 
1025 		/*
1026 		 * The SCSI standard suggests that in MSGOUT phase, the
1027 		 * initiator should drop ATN on the last byte of the message
1028 		 * phase after REQ has been asserted for the handshake but
1029 		 * before the initiator raises ACK.
1030 		 * Don't know how to accomplish this on the ST01/02.
1031 		 */
1032 
1033 #if 0
1034 		/*
1035 		 * XXX
1036 		 * The st01 code doesn't wait for STAT_REQ to be deasserted.
1037 		 * Is this ok?
1038 		 */
1039 		for (timeout = 0; timeout < 200000L; timeout++)
1040 			if (!(STATUS & STAT_REQ))
1041 				break;
1042 		if (STATUS & STAT_REQ)
1043 			printf("%s: timeout on wait for !STAT_REQ",
1044 			    sea->sc_dev.dv_xname);
1045 #endif
1046 	} while (--c);
1047 
1048 	*count = c;
1049 	*data = d;
1050 	tmp = STATUS;
1051 	if (tmp & STAT_REQ)
1052 		*phase = tmp & PH_MASK;
1053 	else
1054 		*phase = PH_INVALID;
1055 
1056 	if (c && (*phase != p))
1057 		return -1;
1058 	return 0;
1059 }
1060 
1061 /*
1062  * Establish I_T_L or I_T_L_Q nexus for new or existing command including
1063  * ARBITRATION, SELECTION, and initial message out for IDENTIFY and queue
1064  * messages.  Return -1 if selection could not execute for some reason, 0 if
1065  * selection succeded or failed because the target did not respond.
1066  */
1067 int
1068 sea_select(sea, scb)
1069 	struct sea_softc *sea;
1070 	struct sea_scb *scb;
1071 {
1072 	u_char msg[3], phase;
1073 	u_char *data;
1074 	int len;
1075 	int timeout;
1076 
1077 	CONTROL = BASE_CMD;
1078 	DATA = sea->our_id_mask;
1079 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_START_ARB;
1080 
1081 	/* wait for arbitration to complete */
1082 	for (timeout = 0; timeout < 3000000L; timeout++)
1083 		if (STATUS & STAT_ARB_CMPL)
1084 			break;
1085 	if (!(STATUS & STAT_ARB_CMPL)) {
1086 		if (STATUS & STAT_SEL) {
1087 			printf("%s: arbitration lost\n", sea->sc_dev.dv_xname);
1088 			scb->flags |= SCB_ERROR;
1089 		} else {
1090 			printf("%s: arbitration timeout\n",
1091 			    sea->sc_dev.dv_xname);
1092 			scb->flags |= SCB_TIMEOUT;
1093 		}
1094 		CONTROL = BASE_CMD;
1095 		return -1;
1096 	}
1097 
1098 	delay(2);
1099 	DATA = (u_char)((1 << scb->xs->xs_periph->periph_target) |
1100 		sea->our_id_mask);
1101 	CONTROL =
1102 #ifdef SEA_NOMSGS
1103 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL;
1104 #else
1105 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL | CMD_ATTN;
1106 #endif
1107 	delay(1);
1108 
1109 	/* wait for a bsy from target */
1110 	for (timeout = 0; timeout < 2000000L; timeout++)
1111 		if (STATUS & STAT_BSY)
1112 			break;
1113 	if (!(STATUS & STAT_BSY)) {
1114 		/* should return some error to the higher level driver */
1115 		CONTROL = BASE_CMD;
1116 		scb->flags |= SCB_TIMEOUT;
1117 		return 0;
1118 	}
1119 
1120 	/* Try to make the target to take a message from us */
1121 #ifdef SEA_NOMSGS
1122 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE;
1123 #else
1124 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_ATTN;
1125 #endif
1126 	delay(1);
1127 
1128 	/* should start a msg_out phase */
1129 	for (timeout = 0; timeout < 2000000L; timeout++)
1130 		if (STATUS & STAT_REQ)
1131 			break;
1132 	/* Remove ATN. */
1133 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1134 	if (!(STATUS & STAT_REQ)) {
1135 		/*
1136 		 * This should not be taken as an error, but more like an
1137 		 * unsupported feature!  Should set a flag indicating that the
1138 		 * target don't support messages, and continue without failure.
1139 		 * (THIS IS NOT AN ERROR!)
1140 		 */
1141 	} else {
1142 		msg[0] = MSG_IDENTIFY(scb->xs->xs_periph->periph_lun, 1);
1143 		len = 1;
1144 		data = msg;
1145 		phase = PH_MSGOUT;
1146 		/* Should do test on result of sea_transfer_pio(). */
1147 		sea_transfer_pio(sea, &phase, &len, &data);
1148 	}
1149 	if (!(STATUS & STAT_BSY))
1150 		printf("%s: after successful arbitrate: no STAT_BSY!\n",
1151 		    sea->sc_dev.dv_xname);
1152 
1153 	sea->nexus = scb;
1154 	sea->busy[scb->xs->xs_periph->periph_target] |=
1155 	    1 << scb->xs->xs_periph->periph_lun;
1156 	/* This assignment should depend on possibility to send a message to target. */
1157 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1158 	/* XXX Reset pointer in command? */
1159 	return 0;
1160 }
1161 
1162 /*
1163  * Send an abort to the target.  Return 1 success, 0 on failure.
1164  */
1165 int
1166 sea_abort(sea, scb)
1167 	struct sea_softc *sea;
1168 	struct sea_scb *scb;
1169 {
1170 	struct sea_scb *tmp;
1171 	u_char msg, phase, *msgptr;
1172 	int len;
1173 
1174 	/*
1175 	 * If the command hasn't been issued yet, we simply remove it from the
1176 	 * issue queue
1177 	 * XXX Could avoid this loop.
1178 	 */
1179 	for (tmp = sea->ready_list.tqh_first; tmp; tmp = tmp->chain.tqe_next)
1180 		if (scb == tmp) {
1181 			TAILQ_REMOVE(&sea->ready_list, scb, chain);
1182 			/* XXX Set some type of error result for operation. */
1183 			return 1;
1184 		}
1185 
1186 	/*
1187 	 * If any commands are connected, we're going to fail the abort and let
1188 	 * the high level SCSI driver retry at a later time or issue a reset.
1189 	 */
1190 	if (sea->nexus)
1191 		return 0;
1192 
1193 	/*
1194 	 * If the command is currently disconnected from the bus, and there are
1195 	 * no connected commands, we reconnect the I_T_L or I_T_L_Q nexus
1196 	 * associated with it, go into message out, and send an abort message.
1197 	 */
1198 	for (tmp = sea->nexus_list.tqh_first; tmp;
1199 	    tmp = tmp->chain.tqe_next)
1200 		if (scb == tmp) {
1201 			if (sea_select(sea, scb))
1202 				return 0;
1203 
1204 			msg = MSG_ABORT;
1205 			msgptr = &msg;
1206 			len = 1;
1207 			phase = PH_MSGOUT;
1208 			CONTROL = BASE_CMD | CMD_ATTN;
1209 			sea_transfer_pio(sea, &phase, &len, &msgptr);
1210 
1211 			for (tmp = sea->nexus_list.tqh_first; tmp;
1212 			    tmp = tmp->chain.tqe_next)
1213 				if (scb == tmp) {
1214 					TAILQ_REMOVE(&sea->nexus_list,
1215 					    scb, chain);
1216 					/* XXX Set some type of error result
1217 					   for the operation. */
1218 					return 1;
1219 				}
1220 		}
1221 
1222 	/* Command not found in any queue; race condition? */
1223 	return 1;
1224 }
1225 
1226 void
1227 sea_done(sea, scb)
1228 	struct sea_softc *sea;
1229 	struct sea_scb *scb;
1230 {
1231 	struct scsipi_xfer *xs = scb->xs;
1232 
1233 	callout_stop(&scb->xs->xs_callout);
1234 
1235 	xs->resid = scb->datalen;
1236 
1237 	/* XXXX need to get status */
1238 	if (scb->flags == SCB_ACTIVE) {
1239 		xs->resid = 0;
1240 	} else {
1241 		if (scb->flags & (SCB_TIMEOUT | SCB_ABORTED))
1242 			xs->error = XS_TIMEOUT;
1243 		if (scb->flags & SCB_ERROR)
1244 			xs->error = XS_DRIVER_STUFFUP;
1245 	}
1246 	sea_free_scb(sea, scb, xs->xs_control);
1247 	scsipi_done(xs);
1248 }
1249 
1250 /*
1251  * Wait for completion of command in polled mode.
1252  */
1253 int
1254 sea_poll(sea, xs, count)
1255 	struct sea_softc *sea;
1256 	struct scsipi_xfer *xs;
1257 	int count;
1258 {
1259 	int s;
1260 
1261 	while (count) {
1262 		/* try to do something */
1263 		s = splbio();
1264 		if (!main_running)
1265 			sea_main();
1266 		splx(s);
1267 		if (xs->xs_status & XS_STS_DONE)
1268 			return 0;
1269 		delay(1000);
1270 		count--;
1271 	}
1272 	return 1;
1273 }
1274 
1275 /*
1276  * Do the transfer.  We know we are connected.  Update the flags, and call
1277  * sea_done() when task accomplished.  Dialog controlled by the target.
1278  */
1279 void
1280 sea_information_transfer(sea)
1281 	struct sea_softc *sea;
1282 {
1283 	int timeout;
1284 	u_char msgout = MSG_NOOP;
1285 	int len;
1286 	int s;
1287 	u_char *data;
1288 	u_char phase, tmp, old_phase = PH_INVALID;
1289 	struct sea_scb *scb = sea->nexus;
1290 	int loop;
1291 
1292 	for (timeout = 0; timeout < 10000000L; timeout++) {
1293 		tmp = STATUS;
1294 		if (tmp & STAT_PARITY)
1295 			printf("%s: parity error detected\n",
1296 			    sea->sc_dev.dv_xname);
1297 		if (!(tmp & STAT_BSY)) {
1298 			for (loop = 0; loop < 20; loop++)
1299 				if ((tmp = STATUS) & STAT_BSY)
1300 					break;
1301 			if (!(tmp & STAT_BSY)) {
1302 				printf("%s: !STAT_BSY unit in data transfer!\n",
1303 				    sea->sc_dev.dv_xname);
1304 				s = splbio();
1305 				sea->nexus = NULL;
1306 				scb->flags = SCB_ERROR;
1307 				splx(s);
1308 				sea_done(sea, scb);
1309 				return;
1310 			}
1311 		}
1312 
1313 		/* we only have a valid SCSI phase when REQ is asserted */
1314 		if (!(tmp & STAT_REQ))
1315 			continue;
1316 
1317 		if (sea->type == FDOMAIN840)
1318 			tmp = ((tmp & 0x08) >> 2) |
1319 			      ((tmp & 0x02) << 2) |
1320 			       (tmp & 0xf5);
1321 		phase = tmp & PH_MASK;
1322 		if (phase != old_phase)
1323 			old_phase = phase;
1324 
1325 		switch (phase) {
1326 		case PH_DATAOUT:
1327 #ifdef SEA_NODATAOUT
1328 			printf("%s: SEA_NODATAOUT set, attempted DATAOUT aborted\n",
1329 			    sea->sc_dev.dv_xname);
1330 			msgout = MSG_ABORT;
1331 			CONTROL = BASE_CMD | CMD_ATTN;
1332 			break;
1333 #endif
1334 		case PH_DATAIN:
1335 			if (!scb->data)
1336 				printf("no data address!\n");
1337 #ifdef SEA_BLINDTRANSFER
1338 			if (scb->datalen && !(scb->datalen % BLOCK_SIZE)) {
1339 				while (scb->datalen) {
1340 					for (loop = 0; loop < 50000; loop++)
1341 						if ((tmp = STATUS) & STAT_REQ)
1342 							break;
1343 					if (!(tmp & STAT_REQ)) {
1344 						printf("%s: timeout waiting for STAT_REQ\n",
1345 						    sea->sc_dev.dv_xname);
1346 						/* XXX Do something? */
1347 					}
1348 					if (sea->type == FDOMAIN840)
1349 						tmp = ((tmp & 0x08) >> 2) |
1350 						      ((tmp & 0x02) << 2) |
1351 						       (tmp & 0xf5);
1352 					if ((tmp & PH_MASK) != phase)
1353 						break;
1354 					if (!(phase & STAT_IO)) {
1355 #ifdef SEA_ASSEMBLER
1356 						caddr_t junk;
1357 						__asm("cld\n\t\
1358 						    rep\n\t\
1359 						    movsl" :
1360 						    "=S" (scb->data),
1361 						    "=c" (len),
1362 						    "=D" (junk) :
1363 						    "0" (scb->data),
1364 						    "1" (BLOCK_SIZE >> 2),
1365 						    "2" (sea->maddr_dr));
1366 #else
1367 					        for (len = BLOCK_SIZE;
1368 						    len; len--)
1369 							DATA = *(scb->data++);
1370 #endif
1371 					} else {
1372 #ifdef SEA_ASSEMBLER
1373 						caddr_t junk;
1374 						__asm("cld\n\t\
1375 						    rep\n\t\
1376 						    movsl" :
1377 						    "=D" (scb->data),
1378 						    "=c" (len),
1379 						    "=S" (junk) :
1380 						    "0" (scb->data),
1381 						    "1" (BLOCK_SIZE >> 2),
1382 						    "2" (sea->maddr_dr));
1383 #else
1384 					        for (len = BLOCK_SIZE;
1385 						    len; len--)
1386 							*(scb->data++) = DATA;
1387 #endif
1388 					}
1389 					scb->datalen -= BLOCK_SIZE;
1390 				}
1391 			}
1392 #endif
1393 			if (scb->datalen)
1394 				sea_transfer_pio(sea, &phase, &scb->datalen,
1395 				    &scb->data);
1396 			break;
1397 		case PH_MSGIN:
1398 			/* Multibyte messages should not be present here. */
1399 			len = 1;
1400 			data = &tmp;
1401 			sea_transfer_pio(sea, &phase, &len, &data);
1402 			/* scb->MessageIn = tmp; */
1403 
1404 			switch (tmp) {
1405 			case MSG_ABORT:
1406 				scb->flags = SCB_ABORTED;
1407 				printf("sea: command aborted by target\n");
1408 				CONTROL = BASE_CMD;
1409 				sea_done(sea, scb);
1410 				return;
1411 			case MSG_CMDCOMPLETE:
1412 				s = splbio();
1413 				sea->nexus = NULL;
1414 				splx(s);
1415 				sea->busy[scb->xs->xs_periph->periph_target] &=
1416 				    ~(1 << scb->xs->xs_periph->periph_lun);
1417 				CONTROL = BASE_CMD;
1418 				sea_done(sea, scb);
1419 				return;
1420 			case MSG_MESSAGE_REJECT:
1421 				printf("%s: message_reject received\n",
1422 				    sea->sc_dev.dv_xname);
1423 				break;
1424 			case MSG_DISCONNECT:
1425 				s = splbio();
1426 				TAILQ_INSERT_TAIL(&sea->nexus_list,
1427 				    scb, chain);
1428 				sea->nexus = NULL;
1429 				CONTROL = BASE_CMD;
1430 				splx(s);
1431 				return;
1432 			case MSG_SAVEDATAPOINTER:
1433 			case MSG_RESTOREPOINTERS:
1434 				/* save/restore of pointers are ignored */
1435 				break;
1436 			default:
1437 				/*
1438 				 * This should be handled in the pio data
1439 				 * transfer phase, as the ATN should be raised
1440 				 * before ACK goes false when rejecting a
1441 				 * message.
1442 				 */
1443 				printf("%s: unknown message in: %x\n",
1444 				    sea->sc_dev.dv_xname, tmp);
1445 				break;
1446 			} /* switch (tmp) */
1447 			break;
1448 		case PH_MSGOUT:
1449 			len = 1;
1450 			data = &msgout;
1451 			/* sea->last_message = msgout; */
1452 			sea_transfer_pio(sea, &phase, &len, &data);
1453 			if (msgout == MSG_ABORT) {
1454 				printf("%s: sent message abort to target\n",
1455 				    sea->sc_dev.dv_xname);
1456 				s = splbio();
1457 				sea->busy[scb->xs->xs_periph->periph_target] &=
1458 				    ~(1 << scb->xs->xs_periph->periph_lun);
1459 				sea->nexus = NULL;
1460 				scb->flags = SCB_ABORTED;
1461 				splx(s);
1462 				/* enable interrupt from scsi */
1463 				sea_done(sea, scb);
1464 				return;
1465 			}
1466 			msgout = MSG_NOOP;
1467 			break;
1468 		case PH_CMD:
1469 			len = scb->xs->cmdlen;
1470 			data = (char *) scb->xs->cmd;
1471 			sea_transfer_pio(sea, &phase, &len, &data);
1472 			break;
1473 		case PH_STAT:
1474 			len = 1;
1475 			data = &tmp;
1476 			sea_transfer_pio(sea, &phase, &len, &data);
1477 			scb->xs->status = tmp;
1478 			break;
1479 		default:
1480 			printf("sea: unknown phase\n");
1481 		} /* switch (phase) */
1482 	} /* for (...) */
1483 
1484 	/* If we get here we have got a timeout! */
1485 	printf("%s: timeout in data transfer\n", sea->sc_dev.dv_xname);
1486 	scb->flags = SCB_TIMEOUT;
1487 	/* XXX Should I clear scsi-bus state? */
1488 	sea_done(sea, scb);
1489 }
1490