xref: /netbsd-src/sys/dev/isa/seagate.c (revision 06be8101a16cc95f40783b3cb7afd12112103a9a)
1 /*	$NetBSD: seagate.c,v 1.43 2001/11/13 08:01:31 lukem 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 1.43 2001/11/13 08:01:31 lukem Exp $");
69 
70 #include <sys/types.h>
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/kernel.h>
74 #include <sys/errno.h>
75 #include <sys/ioctl.h>
76 #include <sys/device.h>
77 #include <sys/buf.h>
78 #include <sys/proc.h>
79 #include <sys/user.h>
80 #include <sys/queue.h>
81 #include <sys/malloc.h>
82 
83 #include <machine/intr.h>
84 #include <machine/pio.h>
85 
86 #include <dev/scsipi/scsi_all.h>
87 #include <dev/scsipi/scsipi_all.h>
88 #include <dev/scsipi/scsi_message.h>
89 #include <dev/scsipi/scsiconf.h>
90 
91 #include <dev/isa/isareg.h>
92 #include <dev/isa/isavar.h>	/* XXX USES ISA HOLE DIRECTLY */
93 
94 #define	SEA_SCB_MAX	32	/* allow maximally 8 scsi control blocks */
95 #define SCB_TABLE_SIZE	8	/* start with 8 scb entries in table */
96 #define BLOCK_SIZE	512	/* size of READ/WRITE areas on SCSI card */
97 
98 /*
99  * defining SEA_BLINDTRANSFER will make DATA IN and DATA OUT to be done with
100  * blind transfers, i.e. no check is done for scsi phase changes. This will
101  * result in data loss if the scsi device does not send its data using
102  * BLOCK_SIZE bytes at a time.
103  * If SEA_BLINDTRANSFER defined and SEA_ASSEMBLER also defined will result in
104  * the use of blind transfers coded in assembler. SEA_ASSEMBLER is no good
105  * without SEA_BLINDTRANSFER defined.
106  */
107 #define	SEA_BLINDTRANSFER	/* do blind transfers */
108 #define	SEA_ASSEMBLER		/* Use assembly code for fast transfers */
109 
110 /*
111  * defining SEA_NOMSGS causes messages not to be used (thereby disabling
112  * disconnects)
113  */
114 #undef	SEA_NOMSGS
115 
116 /*
117  * defining SEA_NODATAOUT makes dataout phase being aborted
118  */
119 #undef	SEA_NODATAOUT
120 
121 /* Debugging definitions. Should not be used unless you want a lot of
122    printouts even under normal conditions */
123 
124 #undef	SEA_DEBUGQUEUE		/* Display info about queue-lengths */
125 
126 /******************************* board definitions **************************/
127 /*
128  * CONTROL defines
129  */
130 #define CMD_RST		0x01		/* scsi reset */
131 #define CMD_SEL		0x02		/* scsi select */
132 #define CMD_BSY		0x04		/* scsi busy */
133 #define	CMD_ATTN	0x08		/* scsi attention */
134 #define CMD_START_ARB	0x10		/* start arbitration bit */
135 #define	CMD_EN_PARITY	0x20		/* enable scsi parity generation */
136 #define CMD_INTR	0x40		/* enable scsi interrupts */
137 #define CMD_DRVR_ENABLE	0x80		/* scsi enable */
138 
139 /*
140  * STATUS
141  */
142 #define STAT_BSY	0x01		/* scsi busy */
143 #define STAT_MSG	0x02		/* scsi msg */
144 #define STAT_IO		0x04		/* scsi I/O */
145 #define STAT_CD		0x08		/* scsi C/D */
146 #define STAT_REQ	0x10		/* scsi req */
147 #define STAT_SEL	0x20		/* scsi select */
148 #define STAT_PARITY	0x40		/* parity error bit */
149 #define STAT_ARB_CMPL	0x80		/* arbitration complete bit */
150 
151 /*
152  * REQUESTS
153  */
154 #define PH_DATAOUT	(0)
155 #define PH_DATAIN	(STAT_IO)
156 #define PH_CMD		(STAT_CD)
157 #define PH_STAT		(STAT_CD | STAT_IO)
158 #define PH_MSGOUT	(STAT_MSG | STAT_CD)
159 #define PH_MSGIN	(STAT_MSG | STAT_CD | STAT_IO)
160 
161 #define PH_MASK		(STAT_MSG | STAT_CD | STAT_IO)
162 
163 #define PH_INVALID	0xff
164 
165 #define SEA_RAMOFFSET	0x00001800
166 
167 #define BASE_CMD	(CMD_INTR | CMD_EN_PARITY)
168 
169 #define	SEAGATE		1	/* Seagate ST0[12] */
170 #define	FDOMAIN		2	/* Future Domain TMC-{885,950} */
171 #define	FDOMAIN840	3	/* Future Domain TMC-{84[01],88[01]} */
172 
173 /******************************************************************************/
174 
175 /* scsi control block used to keep info about a scsi command */
176 struct sea_scb {
177         u_char *data;			/* position in data buffer so far */
178 	int datalen;			/* bytes remaining to transfer */
179 	TAILQ_ENTRY(sea_scb) chain;
180 	struct scsipi_xfer *xs;		/* the scsipi_xfer for this cmd */
181 	int flags;			/* status of the instruction */
182 #define	SCB_FREE	0
183 #define	SCB_ACTIVE	1
184 #define SCB_ABORTED	2
185 #define SCB_TIMEOUT	4
186 #define SCB_ERROR	8
187 };
188 
189 /*
190  * data structure describing current status of the scsi bus. One for each
191  * controller card.
192  */
193 struct sea_softc {
194 	struct device sc_dev;
195 	void *sc_ih;
196 
197 	int type;			/* board type */
198 	caddr_t	maddr;			/* Base address for card */
199 	caddr_t	maddr_cr_sr;		/* Address of control and status reg */
200 	caddr_t	maddr_dr;		/* Address of data register */
201 
202 	struct scsipi_adapter sc_adapter;
203 	struct scsipi_channel sc_channel;
204 
205 	TAILQ_HEAD(, sea_scb) free_list, ready_list, nexus_list;
206 	struct sea_scb *nexus;		/* currently connected command */
207 	int numscbs;			/* number of scsi control blocks */
208 	struct sea_scb scb[SCB_TABLE_SIZE];
209 
210 	int our_id;			/* our scsi id */
211 	u_char our_id_mask;
212 	volatile u_char busy[8];	/* index=target, bit=lun, Keep track of
213 					   busy luns at device target */
214 };
215 
216 /* flag showing if main routine is running. */
217 static volatile int main_running = 0;
218 
219 #define	STATUS	(*(volatile u_char *)sea->maddr_cr_sr)
220 #define CONTROL	STATUS
221 #define DATA	(*(volatile u_char *)sea->maddr_dr)
222 
223 /*
224  * These are "special" values for the tag parameter passed to sea_select
225  * Not implemented right now.
226  */
227 #define TAG_NEXT	-1	/* Use next free tag */
228 #define TAG_NONE	-2	/*
229 				 * Establish I_T_L nexus instead of I_T_L_Q
230 				 * even on SCSI-II devices.
231 				 */
232 
233 typedef struct {
234 	char *signature;
235 	int offset, length;
236 	int type;
237 } BiosSignature;
238 
239 /*
240  * Signatures for automatic recognition of board type
241  */
242 static const BiosSignature signatures[] = {
243 {"ST01 v1.7  (C) Copyright 1987 Seagate", 15, 37, SEAGATE},
244 {"SCSI BIOS 2.00  (C) Copyright 1987 Seagate", 15, 40, SEAGATE},
245 
246 /*
247  * The following two lines are NOT mistakes. One detects ROM revision
248  * 3.0.0, the other 3.2. Since seagate has only one type of SCSI adapter,
249  * and this is not going to change, the "SEAGATE" and "SCSI" together
250  * are probably "good enough"
251  */
252 {"SEAGATE SCSI BIOS ", 16, 17, SEAGATE},
253 {"SEAGATE SCSI BIOS ", 17, 17, SEAGATE},
254 
255 /*
256  * However, future domain makes several incompatible SCSI boards, so specific
257  * signatures must be used.
258  */
259 {"FUTURE DOMAIN CORP. (C) 1986-1989 V5.0C2/14/89", 5, 45, FDOMAIN},
260 {"FUTURE DOMAIN CORP. (C) 1986-1989 V6.0A7/28/89", 5, 46, FDOMAIN},
261 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0105/31/90",5, 47, FDOMAIN},
262 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0209/18/90",5, 47, FDOMAIN},
263 {"FUTURE DOMAIN CORP. (C) 1986-1990 V7.009/18/90", 5, 46, FDOMAIN},
264 {"FUTURE DOMAIN CORP. (C) 1992 V8.00.004/02/92",   5, 44, FDOMAIN},
265 {"FUTURE DOMAIN TMC-950",			   5, 21, FDOMAIN},
266 };
267 
268 #define	nsignatures	(sizeof(signatures) / sizeof(signatures[0]))
269 
270 #ifdef notdef
271 static const char *bases[] = {
272 	(char *) 0xc8000, (char *) 0xca000, (char *) 0xcc000,
273 	(char *) 0xce000, (char *) 0xdc000, (char *) 0xde000
274 };
275 
276 #define	nbases		(sizeof(bases) / sizeof(bases[0]))
277 #endif
278 
279 int seaintr __P((void *));
280 void sea_scsipi_request __P((struct scsipi_channel *,
281 	scsipi_adapter_req_t, void *));
282 void sea_timeout __P((void *));
283 void sea_done __P((struct sea_softc *, struct sea_scb *));
284 struct sea_scb *sea_get_scb __P((struct sea_softc *, int));
285 void sea_free_scb __P((struct sea_softc *, struct sea_scb *, int));
286 static void sea_main __P((void));
287 static void sea_information_transfer __P((struct sea_softc *));
288 int sea_poll __P((struct sea_softc *, struct scsipi_xfer *, int));
289 void sea_init __P((struct sea_softc *));
290 void sea_send_scb __P((struct sea_softc *sea, struct sea_scb *scb));
291 void sea_reselect __P((struct sea_softc *sea));
292 int sea_select __P((struct sea_softc *sea, struct sea_scb *scb));
293 int sea_transfer_pio __P((struct sea_softc *sea, u_char *phase,
294     int *count, u_char **data));
295 int sea_abort __P((struct sea_softc *, struct sea_scb *scb));
296 
297 void	sea_grow_scb __P((struct sea_softc *));
298 
299 int	seaprobe __P((struct device *, struct cfdata *, void *));
300 void	seaattach __P((struct device *, struct device *, void *));
301 
302 struct cfattach sea_ca = {
303 	sizeof(struct sea_softc), seaprobe, seaattach
304 };
305 
306 extern struct cfdriver sea_cd;
307 
308 #ifdef SEA_DEBUGQUEUE
309 void
310 sea_queue_length(sea)
311 	struct sea_softc *sea;
312 {
313 	struct sea_scb *scb;
314 	int connected, issued, disconnected;
315 
316 	connected = sea->nexus ? 1 : 0;
317 	for (scb = sea->ready_list.tqh_first, issued = 0; scb;
318 	    scb = scb->chain.tqe_next, issued++);
319 	for (scb = sea->nexus_list.tqh_first, disconnected = 0; scb;
320 	    scb = scb->chain.tqe_next, disconnected++);
321 	printf("%s: length: %d/%d/%d\n", sea->sc_dev.dv_xname, connected,
322 	    issued, disconnected);
323 }
324 #endif
325 
326 /*
327  * Check if the device can be found at the port given and if so, detect the
328  * type the type of board.  Set it up ready for further work. Takes the isa_dev
329  * structure from autoconf as an argument.
330  * Returns 1 if card recognized, 0 if errors.
331  */
332 int
333 seaprobe(parent, match, aux)
334 	struct device *parent;
335 	struct cfdata *match;
336 	void *aux;
337 {
338 	struct isa_attach_args *ia = aux;
339 	int i, type = 0;
340 	caddr_t maddr;
341 
342 	/*
343 	 * Could try to find a board by looking through all possible addresses.
344 	 * This is not done the right way now, because I have not found a way
345 	 * to get a boards virtual memory address given its physical.  There is
346 	 * a function that returns the physical address for a given virtual
347 	 * address, but not the other way around.
348 	 */
349 
350 	if (ia->ia_maddr == MADDRUNK) {
351 		/* XXX */
352 		return 0;
353 	} else
354 		maddr = ISA_HOLE_VADDR(ia->ia_maddr);
355 
356 	/* check board type */	/* No way to define this through config */
357 	for (i = 0; i < nsignatures; i++)
358 		if (!memcmp(maddr + signatures[i].offset,
359 		    signatures[i].signature, signatures[i].length)) {
360 			type = signatures[i].type;
361 			break;
362 		}
363 
364 	/* Find controller and data memory addresses */
365 	switch (type) {
366 	case SEAGATE:
367 	case FDOMAIN840:
368 	case FDOMAIN:
369 		break;
370 	default:
371 #ifdef DEBUG
372 		printf("seaprobe: board type unknown at address 0x%x\n",
373 		    ia->ia_maddr);
374 #endif
375 		return 0;
376 	}
377 
378 	ia->ia_drq = DRQUNK;
379 	ia->ia_msize = 0x2000;
380 	ia->ia_iosize = 0;
381 	return 1;
382 }
383 
384 /*
385  * Attach all sub-devices we can find
386  */
387 void
388 seaattach(parent, self, aux)
389 	struct device *parent, *self;
390 	void *aux;
391 {
392 	struct isa_attach_args *ia = aux;
393 	struct sea_softc *sea = (void *)self;
394 	struct scsipi_adapter *adapt = &sea->sc_adapter;
395 	struct scsipi_channel *chan = &sea->sc_channel;
396 	int i;
397 
398 	sea->maddr = ISA_HOLE_VADDR(ia->ia_maddr);
399 
400 	/* check board type */	/* No way to define this through config */
401 	for (i = 0; i < nsignatures; i++)
402 		if (!memcmp(sea->maddr + signatures[i].offset,
403 		    signatures[i].signature, signatures[i].length)) {
404 			sea->type = signatures[i].type;
405 			break;
406 		}
407 
408 	/* Find controller and data memory addresses */
409 	switch (sea->type) {
410 	case SEAGATE:
411 	case FDOMAIN840:
412 		sea->maddr_cr_sr =
413 		    (void *) (((u_char *)sea->maddr) + 0x1a00);
414 		sea->maddr_dr =
415 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
416 		break;
417 	case FDOMAIN:
418 		sea->maddr_cr_sr =
419 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
420 		sea->maddr_dr =
421 		    (void *) (((u_char *)sea->maddr) + 0x1e00);
422 		break;
423 	default:
424 #ifdef DEBUG
425 		printf("%s: board type unknown at address 0x%x\n",
426 		    sea->sc_dev.dv_xname, ia->ia_maddr);
427 #endif
428 		return;
429 	}
430 
431 	/* Test controller RAM (works the same way on future domain cards?) */
432 	*((u_char *)sea->maddr + SEA_RAMOFFSET) = 0xa5;
433 	*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) = 0x5a;
434 
435 	if ((*((u_char *)sea->maddr + SEA_RAMOFFSET) != 0xa5) ||
436 	    (*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) != 0x5a)) {
437 		printf("%s: board RAM failure\n", sea->sc_dev.dv_xname);
438 		return;
439 	}
440 
441 	sea_init(sea);
442 
443 	/*
444 	 * Fill in the scsipi_adapter.
445 	 */
446 	memset(adapt, 0, sizeof(*adapt));
447 	adapt->adapt_dev = &sea->sc_dev;
448 	adapt->adapt_nchannels = 1;
449 	adapt->adapt_openings = sea->numscbs;
450 	adapt->adapt_max_periph = 1;
451 	adapt->adapt_request = sea_scsipi_request;
452 	adapt->adapt_minphys = minphys;
453 
454 	/*
455 	 * Fill in the scsipi_channel.
456 	 */
457 	memset(chan, 0, sizeof(*chan));
458 	chan->chan_adapter = adapt;
459 	chan->chan_bustype = &scsi_bustype;
460 	chan->chan_channel = 0;
461 	chan->chan_ntargets = 8;
462 	chan->chan_nluns = 8;
463 	chan->chan_id = sea->our_id;
464 	chan->chan_flags = SCSIPI_CHAN_CANGROW;
465 
466 	printf("\n");
467 
468 	sea->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq, IST_EDGE,
469 	    IPL_BIO, seaintr, sea);
470 
471 	/*
472 	 * ask the adapter what subunits are present
473 	 */
474 	config_found(self, &sea->sc_channel, scsiprint);
475 }
476 
477 /*
478  * Catch an interrupt from the adaptor
479  */
480 int
481 seaintr(arg)
482 	void *arg;
483 {
484 	struct sea_softc *sea = arg;
485 
486 #ifdef DEBUG	/* extra overhead, and only needed for intr debugging */
487 	if ((STATUS & STAT_PARITY) == 0 &&
488 	    (STATUS & (STAT_SEL | STAT_IO)) != (STAT_SEL | STAT_IO))
489 		return 0;
490 #endif
491 
492 loop:
493 	/* dispatch to appropriate routine if found and done=0 */
494 	/* should check to see that this card really caused the interrupt */
495 
496 	if (STATUS & STAT_PARITY) {
497 		/* Parity error interrupt */
498 		printf("%s: parity error\n", sea->sc_dev.dv_xname);
499 		return 1;
500 	}
501 
502 	if ((STATUS & (STAT_SEL | STAT_IO)) == (STAT_SEL | STAT_IO)) {
503 		/* Reselect interrupt */
504 		sea_reselect(sea);
505 		if (!main_running)
506 			sea_main();
507 		goto loop;
508 	}
509 
510 	return 1;
511 }
512 
513 /*
514  * Setup data structures, and reset the board and the SCSI bus.
515  */
516 void
517 sea_init(sea)
518 	struct sea_softc *sea;
519 {
520 	int i;
521 
522 	/* Reset the scsi bus (I don't know if this is needed */
523 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_RST;
524 	delay(25);	/* hold reset for at least 25 microseconds */
525 	CONTROL = BASE_CMD;
526 	delay(10); 	/* wait a Bus Clear Delay (800 ns + bus free delay (800 ns) */
527 
528 	/* Set our id (don't know anything about this) */
529 	switch (sea->type) {
530 	case SEAGATE:
531 		sea->our_id = 7;
532 		break;
533 	case FDOMAIN:
534 	case FDOMAIN840:
535 		sea->our_id = 6;
536 		break;
537 	}
538 	sea->our_id_mask = 1 << sea->our_id;
539 
540 	/* init fields used by our routines */
541 	sea->nexus = 0;
542 	TAILQ_INIT(&sea->ready_list);
543 	TAILQ_INIT(&sea->nexus_list);
544 	TAILQ_INIT(&sea->free_list);
545 	for (i = 0; i < 8; i++)
546 		sea->busy[i] = 0x00;
547 
548 	/* link up the free list of scbs */
549 	sea->numscbs = SCB_TABLE_SIZE;
550 	for (i = 0; i < SCB_TABLE_SIZE; i++) {
551 		TAILQ_INSERT_TAIL(&sea->free_list, &sea->scb[i], chain);
552 	}
553 }
554 
555 /*
556  * start a scsi operation given the command and the data address. Also needs
557  * the unit, target and lu.
558  */
559 void
560 sea_scsipi_request(chan, req, arg)
561 	struct scsipi_channel *chan;
562 	scsipi_adapter_req_t req;
563 	void *arg;
564 {
565 	struct scsipi_xfer *xs;
566 	struct scsipi_periph *periph;
567 	struct sea_softc *sea = (void *)chan->chan_adapter->adapt_dev;
568 	struct sea_scb *scb;
569 	int flags;
570 	int s;
571 
572 	switch (req) {
573 	case ADAPTER_REQ_RUN_XFER:
574 		xs = arg;
575 		periph = xs->xs_periph;
576 		flags = xs->xs_control;
577 
578 		SC_DEBUG(periph, SCSIPI_DB2, ("sea_scsipi_requeset\n"));
579 
580 		/* XXX Reset not implemented. */
581 		if (flags & XS_CTL_RESET) {
582 			printf("%s: resetting\n", sea->sc_dev.dv_xname);
583 			xs->error = XS_DRIVER_STUFFUP;
584 			scsipi_done(xs);
585 			return;
586 		}
587 
588 		/* Get an SCB to use. */
589 		scb = sea_get_scb(sea, flags);
590 #ifdef DIAGNOSTIC
591 		/*
592 		 * This should never happen as we track the resources
593 		 * in the mid-layer.
594 		 */
595 		if (scb == NULL) {
596 			scsipi_printaddr(periph);
597 			printf("unable to allocate scb\n");
598 			panic("sea_scsipi_request");
599 		}
600 #endif
601 
602 		scb->flags = SCB_ACTIVE;
603 		scb->xs = xs;
604 
605 		/*
606 		 * Put all the arguments for the xfer in the scb
607 		 */
608 		scb->datalen = xs->datalen;
609 		scb->data = xs->data;
610 
611 #ifdef SEA_DEBUGQUEUE
612 		sea_queue_length(sea);
613 #endif
614 
615 		s = splbio();
616 
617 		sea_send_scb(sea, scb);
618 
619 		if ((flags & XS_CTL_POLL) == 0) {
620 			callout_reset(&scb->xs->xs_callout,
621 			    (xs->timeout * hz) / 1000, sea_timeout, scb);
622 			splx(s);
623 			return;
624 		}
625 
626 		splx(s);
627 
628 		/*
629 		 * If we can't use interrupts, poll on completion
630 		 */
631 		if (sea_poll(sea, xs, xs->timeout)) {
632 			sea_timeout(scb);
633 			if (sea_poll(sea, xs, 2000))
634 				sea_timeout(scb);
635 		}
636 		return;
637 
638 	case ADAPTER_REQ_GROW_RESOURCES:
639 		sea_grow_scb(sea);
640 		return;
641 
642 	case ADAPTER_REQ_SET_XFER_MODE:
643 	    {
644 		struct scsipi_xfer_mode *xm = arg;
645 
646 		/*
647 		 * We don't support sync or wide or tagged queueing,
648 		 * so announce that now.
649 		 */
650 		xm->xm_mode = 0;
651 		xm->xm_period = 0;
652 		xm->xm_offset = 0;
653 		scsipi_async_event(chan, ASYNC_EVENT_XFER_MODE, xm);
654 		return;
655 	    }
656 	}
657 }
658 
659 /*
660  * Get a free scb. If there are none, see if we can allocate a new one.  If so,
661  * put it in the hash table too; otherwise return an error or sleep.
662  */
663 struct sea_scb *
664 sea_get_scb(sea, flags)
665 	struct sea_softc *sea;
666 	int flags;
667 {
668 	int s;
669 	struct sea_scb *scb;
670 
671 	s = splbio();
672 	if ((scb = TAILQ_FIRST(&sea->free_list)) != NULL)
673 		TAILQ_REMOVE(&sea->free_list, scb, chain);
674 	splx(s);
675 
676 	return (scb);
677 }
678 
679 /*
680  * Try to send this command to the board. Because this board does not use any
681  * mailboxes, this routine simply adds the command to the queue held by the
682  * sea_softc structure.
683  * A check is done to see if the command contains a REQUEST_SENSE command, and
684  * if so the command is put first in the queue, otherwise the command is added
685  * to the end of the queue. ?? Not correct ??
686  */
687 void
688 sea_send_scb(sea, scb)
689 	struct sea_softc *sea;
690 	struct sea_scb *scb;
691 {
692 
693 	TAILQ_INSERT_TAIL(&sea->ready_list, scb, chain);
694 	/* Try to do some work on the card. */
695 	if (!main_running)
696 		sea_main();
697 }
698 
699 /*
700  * Coroutine that runs as long as more work can be done on the seagate host
701  * adapter in a system.  Both sea_scsi_cmd and sea_intr will try to start it in
702  * case it is not running.
703  */
704 
705 void
706 sea_main()
707 {
708 	struct sea_softc *sea;
709 	struct sea_scb *scb;
710 	int done;
711 	int unit;
712 	int s;
713 
714 	main_running = 1;
715 
716 	/*
717 	 * This should not be run with interrupts disabled, but use the splx
718 	 * code instead.
719 	 */
720 loop:
721 	done = 1;
722 	for (unit = 0; unit < sea_cd.cd_ndevs; unit++) {
723 		sea = device_lookup(&sea_cd, unit);
724 		if (!sea)
725 			continue;
726 		s = splbio();
727 		if (!sea->nexus) {
728 			/*
729 			 * Search through the ready_list for a command
730 			 * destined for a target that's not busy.
731 			 */
732 			for (scb = sea->ready_list.tqh_first; scb;
733 			    scb = scb->chain.tqe_next) {
734 				if (!(sea->busy[scb->xs->xs_periph->periph_target] &
735 				    (1 << scb->xs->xs_periph->periph_lun))) {
736 					TAILQ_REMOVE(&sea->ready_list, scb,
737 					    chain);
738 
739 					/* Re-enable interrupts. */
740 					splx(s);
741 
742 					/*
743 					 * Attempt to establish an I_T_L nexus.
744 					 * On success, sea->nexus is set.
745 					 * On failure, we must add the command
746 					 * back to the issue queue so we can
747 					 * keep trying.
748 					 */
749 
750 					/*
751 					 * REQUEST_SENSE commands are issued
752 					 * without tagged queueing, even on
753 					 * SCSI-II devices because the
754 					 * contingent alligence condition
755 					 * exists for the entire unit.
756 					 */
757 
758 					/*
759 					 * First check that if any device has
760 					 * tried a reconnect while we have done
761 					 * other things with interrupts
762 					 * disabled.
763 					 */
764 
765 					if ((STATUS & (STAT_SEL | STAT_IO)) ==
766 					    (STAT_SEL | STAT_IO)) {
767 						sea_reselect(sea);
768 						break;
769 					}
770 					if (sea_select(sea, scb)) {
771 						s = splbio();
772 						TAILQ_INSERT_HEAD(&sea->ready_list,
773 						    scb, chain);
774 						splx(s);
775 					} else
776 						break;
777 				} /* if target/lun is not busy */
778 			} /* for scb */
779 			if (!sea->nexus) {
780 				/* check for reselection phase */
781 				if ((STATUS & (STAT_SEL | STAT_IO)) ==
782 				    (STAT_SEL | STAT_IO)) {
783 					sea_reselect(sea);
784 				}
785 			}
786 		} /* if (!sea->nexus) */
787 
788 		splx(s);
789 		if (sea->nexus) {	/* we are connected. Do the task */
790 			sea_information_transfer(sea);
791 			done = 0;
792 		} else
793 			break;
794 	} /* for instance */
795 
796 	if (!done)
797 		goto loop;
798 
799 	main_running = 0;
800 }
801 
802 /*
803  * Allocate an scb and add it to the free list.
804  * We are called at splbio.
805  */
806 void
807 sea_grow_scb(sea)
808 	struct sea_softc *sea;
809 {
810 	struct sea_scb *scb;
811 
812 	if (sea->numscbs == SEA_SCB_MAX) {
813 		sea->sc_channel.chan_flags &= ~SCSIPI_CHAN_CANGROW;
814 		return;
815 	}
816 
817 	scb = malloc(sizeof(struct sea_scb), M_DEVBUF, M_NOWAIT);
818 	if (scb == NULL)
819 		return;
820 
821 	memset(scb, 0, sizeof(struct sea_scb));
822 
823 	TAILQ_INSERT_TAIL(&sea->free_list, scb, chain);
824 	sea->numscbs++;
825 	sea->sc_adapter.adapt_openings++;
826 }
827 void
828 sea_free_scb(sea, scb, flags)
829 	struct sea_softc *sea;
830 	struct sea_scb *scb;
831 	int flags;
832 {
833 	int s;
834 
835 	s = splbio();
836 	scb->flags = SCB_FREE;
837 	TAILQ_INSERT_HEAD(&sea->free_list, scb, chain);
838 	splx(s);
839 }
840 
841 void
842 sea_timeout(arg)
843 	void *arg;
844 {
845 	struct sea_scb *scb = arg;
846 	struct scsipi_xfer *xs = scb->xs;
847 	struct scsipi_periph *periph = xs->xs_periph;
848 	struct sea_softc *sea =
849 	    (void *)periph->periph_channel->chan_adapter->adapt_dev;
850 	int s;
851 
852 	scsipi_printaddr(periph);
853 	printf("timed out");
854 
855 	s = splbio();
856 
857 	/*
858 	 * If it has been through before, then
859 	 * a previous abort has failed, don't
860 	 * try abort again
861 	 */
862 	if (scb->flags & SCB_ABORTED) {
863 		/* abort timed out */
864 		printf(" AGAIN\n");
865 	 	scb->xs->xs_retries = 0;
866 		scb->flags |= SCB_ABORTED;
867 		sea_done(sea, scb);
868 	} else {
869 		/* abort the operation that has timed out */
870 		printf("\n");
871 		scb->flags |= SCB_ABORTED;
872 		sea_abort(sea, scb);
873 		/* 2 secs for the abort */
874 		if ((xs->xs_control & XS_CTL_POLL) == 0)
875 			callout_reset(&scb->xs->xs_callout, 2 * hz,
876 			    sea_timeout, scb);
877 	}
878 
879 	splx(s);
880 }
881 
882 void
883 sea_reselect(sea)
884 	struct sea_softc *sea;
885 {
886 	u_char target_mask;
887 	int i;
888 	u_char lun, phase;
889 	u_char msg[3];
890 	int len;
891 	u_char *data;
892 	struct sea_scb *scb;
893 	int abort = 0;
894 
895 	if (!((target_mask = STATUS) & STAT_SEL)) {
896 		printf("%s: wrong state 0x%x\n", sea->sc_dev.dv_xname,
897 		    target_mask);
898 		return;
899 	}
900 
901 	/* wait for a device to win the reselection phase */
902 	/* signals this by asserting the I/O signal */
903 	for (i = 10; i && (STATUS & (STAT_SEL | STAT_IO | STAT_BSY)) !=
904 	    (STAT_SEL | STAT_IO | 0); i--);
905 	/* !! Check for timeout here */
906 	/* the data bus contains original initiator id ORed with target id */
907 	target_mask = DATA;
908 	/* see that we really are the initiator */
909 	if (!(target_mask & sea->our_id_mask)) {
910 		printf("%s: polled reselection was not for me: 0x%x\n",
911 		    sea->sc_dev.dv_xname, target_mask);
912 		return;
913 	}
914 	/* find target who won */
915 	target_mask &= ~sea->our_id_mask;
916 	/* host responds by asserting the BSY signal */
917 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY;
918 	/* target should respond by deasserting the SEL signal */
919 	for (i = 50000; i && (STATUS & STAT_SEL); i++);
920 	/* remove the busy status */
921 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
922 	/* we are connected. Now we wait for the MSGIN condition */
923 	for (i = 50000; i && !(STATUS & STAT_REQ); i--);
924 	/* !! Add timeout check here */
925 	/* hope we get an IDENTIFY message */
926 	len = 3;
927 	data = msg;
928 	phase = PH_MSGIN;
929 	sea_transfer_pio(sea, &phase, &len, &data);
930 
931 	if (!MSG_ISIDENTIFY(msg[0])) {
932 		printf("%s: expecting IDENTIFY message, got 0x%x\n",
933 		    sea->sc_dev.dv_xname, msg[0]);
934 		abort = 1;
935 		scb = NULL;
936 	} else {
937 		lun = msg[0] & 0x07;
938 
939 		/*
940 		 * Find the command corresponding to the I_T_L or I_T_L_Q nexus
941 		 * we just reestablished, and remove it from the disconnected
942 		 * queue.
943 		 */
944 		for (scb = sea->nexus_list.tqh_first; scb;
945 		    scb = scb->chain.tqe_next)
946 			if (target_mask == (1 << scb->xs->xs_periph->periph_target) &&
947 			    lun == scb->xs->xs_periph->periph_lun) {
948 				TAILQ_REMOVE(&sea->nexus_list, scb,
949 				    chain);
950 				break;
951 			}
952 		if (!scb) {
953 			printf("%s: target %02x lun %d not disconnected\n",
954 			    sea->sc_dev.dv_xname, target_mask, lun);
955 			/*
956 			 * Since we have an established nexus that we can't do
957 			 * anything with, we must abort it.
958 			 */
959 			abort = 1;
960 		}
961 	}
962 
963 	if (abort) {
964 		msg[0] = MSG_ABORT;
965 		len = 1;
966 		data = msg;
967 		phase = PH_MSGOUT;
968 		CONTROL = BASE_CMD | CMD_ATTN;
969 		sea_transfer_pio(sea, &phase, &len, &data);
970 	} else
971 		sea->nexus = scb;
972 
973 	return;
974 }
975 
976 /*
977  * Transfer data in given phase using polled I/O.
978  */
979 int
980 sea_transfer_pio(sea, phase, count, data)
981 	struct sea_softc *sea;
982 	u_char *phase;
983 	int *count;
984 	u_char **data;
985 {
986 	u_char p = *phase, tmp;
987 	int c = *count;
988 	u_char *d = *data;
989 	int timeout;
990 
991 	do {
992 		/*
993 		 * Wait for assertion of REQ, after which the phase bits will
994 		 * be valid.
995 		 */
996 		for (timeout = 0; timeout < 50000; timeout++)
997 			if ((tmp = STATUS) & STAT_REQ)
998 				break;
999 		if (!(tmp & STAT_REQ)) {
1000 			printf("%s: timeout waiting for STAT_REQ\n",
1001 			    sea->sc_dev.dv_xname);
1002 			break;
1003 		}
1004 
1005 		/*
1006 		 * Check for phase mismatch.  Reached if the target decides
1007 		 * that it has finished the transfer.
1008 		 */
1009 		if (sea->type == FDOMAIN840)
1010 			tmp = ((tmp & 0x08) >> 2) |
1011 			      ((tmp & 0x02) << 2) |
1012 			       (tmp & 0xf5);
1013 		if ((tmp & PH_MASK) != p)
1014 			break;
1015 
1016 		/* Do actual transfer from SCSI bus to/from memory. */
1017 		if (!(p & STAT_IO))
1018 			DATA = *d;
1019 		else
1020 			*d = DATA;
1021 		++d;
1022 
1023 		/*
1024 		 * The SCSI standard suggests that in MSGOUT phase, the
1025 		 * initiator should drop ATN on the last byte of the message
1026 		 * phase after REQ has been asserted for the handshake but
1027 		 * before the initiator raises ACK.
1028 		 * Don't know how to accomplish this on the ST01/02.
1029 		 */
1030 
1031 #if 0
1032 		/*
1033 		 * XXX
1034 		 * The st01 code doesn't wait for STAT_REQ to be deasserted.
1035 		 * Is this ok?
1036 		 */
1037 		for (timeout = 0; timeout < 200000L; timeout++)
1038 			if (!(STATUS & STAT_REQ))
1039 				break;
1040 		if (STATUS & STAT_REQ)
1041 			printf("%s: timeout on wait for !STAT_REQ",
1042 			    sea->sc_dev.dv_xname);
1043 #endif
1044 	} while (--c);
1045 
1046 	*count = c;
1047 	*data = d;
1048 	tmp = STATUS;
1049 	if (tmp & STAT_REQ)
1050 		*phase = tmp & PH_MASK;
1051 	else
1052 		*phase = PH_INVALID;
1053 
1054 	if (c && (*phase != p))
1055 		return -1;
1056 	return 0;
1057 }
1058 
1059 /*
1060  * Establish I_T_L or I_T_L_Q nexus for new or existing command including
1061  * ARBITRATION, SELECTION, and initial message out for IDENTIFY and queue
1062  * messages.  Return -1 if selection could not execute for some reason, 0 if
1063  * selection succeded or failed because the target did not respond.
1064  */
1065 int
1066 sea_select(sea, scb)
1067 	struct sea_softc *sea;
1068 	struct sea_scb *scb;
1069 {
1070 	u_char msg[3], phase;
1071 	u_char *data;
1072 	int len;
1073 	int timeout;
1074 
1075 	CONTROL = BASE_CMD;
1076 	DATA = sea->our_id_mask;
1077 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_START_ARB;
1078 
1079 	/* wait for arbitration to complete */
1080 	for (timeout = 0; timeout < 3000000L; timeout++)
1081 		if (STATUS & STAT_ARB_CMPL)
1082 			break;
1083 	if (!(STATUS & STAT_ARB_CMPL)) {
1084 		if (STATUS & STAT_SEL) {
1085 			printf("%s: arbitration lost\n", sea->sc_dev.dv_xname);
1086 			scb->flags |= SCB_ERROR;
1087 		} else {
1088 			printf("%s: arbitration timeout\n",
1089 			    sea->sc_dev.dv_xname);
1090 			scb->flags |= SCB_TIMEOUT;
1091 		}
1092 		CONTROL = BASE_CMD;
1093 		return -1;
1094 	}
1095 
1096 	delay(2);
1097 	DATA = (u_char)((1 << scb->xs->xs_periph->periph_target) |
1098 		sea->our_id_mask);
1099 	CONTROL =
1100 #ifdef SEA_NOMSGS
1101 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL;
1102 #else
1103 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL | CMD_ATTN;
1104 #endif
1105 	delay(1);
1106 
1107 	/* wait for a bsy from target */
1108 	for (timeout = 0; timeout < 2000000L; timeout++)
1109 		if (STATUS & STAT_BSY)
1110 			break;
1111 	if (!(STATUS & STAT_BSY)) {
1112 		/* should return some error to the higher level driver */
1113 		CONTROL = BASE_CMD;
1114 		scb->flags |= SCB_TIMEOUT;
1115 		return 0;
1116 	}
1117 
1118 	/* Try to make the target to take a message from us */
1119 #ifdef SEA_NOMSGS
1120 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE;
1121 #else
1122 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_ATTN;
1123 #endif
1124 	delay(1);
1125 
1126 	/* should start a msg_out phase */
1127 	for (timeout = 0; timeout < 2000000L; timeout++)
1128 		if (STATUS & STAT_REQ)
1129 			break;
1130 	/* Remove ATN. */
1131 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1132 	if (!(STATUS & STAT_REQ)) {
1133 		/*
1134 		 * This should not be taken as an error, but more like an
1135 		 * unsupported feature!  Should set a flag indicating that the
1136 		 * target don't support messages, and continue without failure.
1137 		 * (THIS IS NOT AN ERROR!)
1138 		 */
1139 	} else {
1140 		msg[0] = MSG_IDENTIFY(scb->xs->xs_periph->periph_lun, 1);
1141 		len = 1;
1142 		data = msg;
1143 		phase = PH_MSGOUT;
1144 		/* Should do test on result of sea_transfer_pio(). */
1145 		sea_transfer_pio(sea, &phase, &len, &data);
1146 	}
1147 	if (!(STATUS & STAT_BSY))
1148 		printf("%s: after successful arbitrate: no STAT_BSY!\n",
1149 		    sea->sc_dev.dv_xname);
1150 
1151 	sea->nexus = scb;
1152 	sea->busy[scb->xs->xs_periph->periph_target] |=
1153 	    1 << scb->xs->xs_periph->periph_lun;
1154 	/* This assignment should depend on possibility to send a message to target. */
1155 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1156 	/* XXX Reset pointer in command? */
1157 	return 0;
1158 }
1159 
1160 /*
1161  * Send an abort to the target.  Return 1 success, 0 on failure.
1162  */
1163 int
1164 sea_abort(sea, scb)
1165 	struct sea_softc *sea;
1166 	struct sea_scb *scb;
1167 {
1168 	struct sea_scb *tmp;
1169 	u_char msg, phase, *msgptr;
1170 	int len;
1171 
1172 	/*
1173 	 * If the command hasn't been issued yet, we simply remove it from the
1174 	 * issue queue
1175 	 * XXX Could avoid this loop.
1176 	 */
1177 	for (tmp = sea->ready_list.tqh_first; tmp; tmp = tmp->chain.tqe_next)
1178 		if (scb == tmp) {
1179 			TAILQ_REMOVE(&sea->ready_list, scb, chain);
1180 			/* XXX Set some type of error result for operation. */
1181 			return 1;
1182 		}
1183 
1184 	/*
1185 	 * If any commands are connected, we're going to fail the abort and let
1186 	 * the high level SCSI driver retry at a later time or issue a reset.
1187 	 */
1188 	if (sea->nexus)
1189 		return 0;
1190 
1191 	/*
1192 	 * If the command is currently disconnected from the bus, and there are
1193 	 * no connected commands, we reconnect the I_T_L or I_T_L_Q nexus
1194 	 * associated with it, go into message out, and send an abort message.
1195 	 */
1196 	for (tmp = sea->nexus_list.tqh_first; tmp;
1197 	    tmp = tmp->chain.tqe_next)
1198 		if (scb == tmp) {
1199 			if (sea_select(sea, scb))
1200 				return 0;
1201 
1202 			msg = MSG_ABORT;
1203 			msgptr = &msg;
1204 			len = 1;
1205 			phase = PH_MSGOUT;
1206 			CONTROL = BASE_CMD | CMD_ATTN;
1207 			sea_transfer_pio(sea, &phase, &len, &msgptr);
1208 
1209 			for (tmp = sea->nexus_list.tqh_first; tmp;
1210 			    tmp = tmp->chain.tqe_next)
1211 				if (scb == tmp) {
1212 					TAILQ_REMOVE(&sea->nexus_list,
1213 					    scb, chain);
1214 					/* XXX Set some type of error result
1215 					   for the operation. */
1216 					return 1;
1217 				}
1218 		}
1219 
1220 	/* Command not found in any queue; race condition? */
1221 	return 1;
1222 }
1223 
1224 void
1225 sea_done(sea, scb)
1226 	struct sea_softc *sea;
1227 	struct sea_scb *scb;
1228 {
1229 	struct scsipi_xfer *xs = scb->xs;
1230 
1231 	callout_stop(&scb->xs->xs_callout);
1232 
1233 	xs->resid = scb->datalen;
1234 
1235 	/* XXXX need to get status */
1236 	if (scb->flags == SCB_ACTIVE) {
1237 		xs->resid = 0;
1238 	} else {
1239 		if (scb->flags & (SCB_TIMEOUT | SCB_ABORTED))
1240 			xs->error = XS_TIMEOUT;
1241 		if (scb->flags & SCB_ERROR)
1242 			xs->error = XS_DRIVER_STUFFUP;
1243 	}
1244 	sea_free_scb(sea, scb, xs->xs_control);
1245 	scsipi_done(xs);
1246 }
1247 
1248 /*
1249  * Wait for completion of command in polled mode.
1250  */
1251 int
1252 sea_poll(sea, xs, count)
1253 	struct sea_softc *sea;
1254 	struct scsipi_xfer *xs;
1255 	int count;
1256 {
1257 	int s;
1258 
1259 	while (count) {
1260 		/* try to do something */
1261 		s = splbio();
1262 		if (!main_running)
1263 			sea_main();
1264 		splx(s);
1265 		if (xs->xs_status & XS_STS_DONE)
1266 			return 0;
1267 		delay(1000);
1268 		count--;
1269 	}
1270 	return 1;
1271 }
1272 
1273 /*
1274  * Do the transfer.  We know we are connected.  Update the flags, and call
1275  * sea_done() when task accomplished.  Dialog controlled by the target.
1276  */
1277 void
1278 sea_information_transfer(sea)
1279 	struct sea_softc *sea;
1280 {
1281 	int timeout;
1282 	u_char msgout = MSG_NOOP;
1283 	int len;
1284 	int s;
1285 	u_char *data;
1286 	u_char phase, tmp, old_phase = PH_INVALID;
1287 	struct sea_scb *scb = sea->nexus;
1288 	int loop;
1289 
1290 	for (timeout = 0; timeout < 10000000L; timeout++) {
1291 		tmp = STATUS;
1292 		if (tmp & STAT_PARITY)
1293 			printf("%s: parity error detected\n",
1294 			    sea->sc_dev.dv_xname);
1295 		if (!(tmp & STAT_BSY)) {
1296 			for (loop = 0; loop < 20; loop++)
1297 				if ((tmp = STATUS) & STAT_BSY)
1298 					break;
1299 			if (!(tmp & STAT_BSY)) {
1300 				printf("%s: !STAT_BSY unit in data transfer!\n",
1301 				    sea->sc_dev.dv_xname);
1302 				s = splbio();
1303 				sea->nexus = NULL;
1304 				scb->flags = SCB_ERROR;
1305 				splx(s);
1306 				sea_done(sea, scb);
1307 				return;
1308 			}
1309 		}
1310 
1311 		/* we only have a valid SCSI phase when REQ is asserted */
1312 		if (!(tmp & STAT_REQ))
1313 			continue;
1314 
1315 		if (sea->type == FDOMAIN840)
1316 			tmp = ((tmp & 0x08) >> 2) |
1317 			      ((tmp & 0x02) << 2) |
1318 			       (tmp & 0xf5);
1319 		phase = tmp & PH_MASK;
1320 		if (phase != old_phase)
1321 			old_phase = phase;
1322 
1323 		switch (phase) {
1324 		case PH_DATAOUT:
1325 #ifdef SEA_NODATAOUT
1326 			printf("%s: SEA_NODATAOUT set, attempted DATAOUT aborted\n",
1327 			    sea->sc_dev.dv_xname);
1328 			msgout = MSG_ABORT;
1329 			CONTROL = BASE_CMD | CMD_ATTN;
1330 			break;
1331 #endif
1332 		case PH_DATAIN:
1333 			if (!scb->data)
1334 				printf("no data address!\n");
1335 #ifdef SEA_BLINDTRANSFER
1336 			if (scb->datalen && !(scb->datalen % BLOCK_SIZE)) {
1337 				while (scb->datalen) {
1338 					for (loop = 0; loop < 50000; loop++)
1339 						if ((tmp = STATUS) & STAT_REQ)
1340 							break;
1341 					if (!(tmp & STAT_REQ)) {
1342 						printf("%s: timeout waiting for STAT_REQ\n",
1343 						    sea->sc_dev.dv_xname);
1344 						/* XXX Do something? */
1345 					}
1346 					if (sea->type == FDOMAIN840)
1347 						tmp = ((tmp & 0x08) >> 2) |
1348 						      ((tmp & 0x02) << 2) |
1349 						       (tmp & 0xf5);
1350 					if ((tmp & PH_MASK) != phase)
1351 						break;
1352 					if (!(phase & STAT_IO)) {
1353 #ifdef SEA_ASSEMBLER
1354 						caddr_t junk;
1355 						asm("cld\n\t\
1356 						    rep\n\t\
1357 						    movsl" :
1358 						    "=S" (scb->data),
1359 						    "=c" (len),
1360 						    "=D" (junk) :
1361 						    "0" (scb->data),
1362 						    "1" (BLOCK_SIZE >> 2),
1363 						    "2" (sea->maddr_dr));
1364 #else
1365 					        for (len = BLOCK_SIZE;
1366 						    len; len--)
1367 							DATA = *(scb->data++);
1368 #endif
1369 					} else {
1370 #ifdef SEA_ASSEMBLER
1371 						caddr_t junk;
1372 						asm("cld\n\t\
1373 						    rep\n\t\
1374 						    movsl" :
1375 						    "=D" (scb->data),
1376 						    "=c" (len),
1377 						    "=S" (junk) :
1378 						    "0" (scb->data),
1379 						    "1" (BLOCK_SIZE >> 2),
1380 						    "2" (sea->maddr_dr));
1381 #else
1382 					        for (len = BLOCK_SIZE;
1383 						    len; len--)
1384 							*(scb->data++) = DATA;
1385 #endif
1386 					}
1387 					scb->datalen -= BLOCK_SIZE;
1388 				}
1389 			}
1390 #endif
1391 			if (scb->datalen)
1392 				sea_transfer_pio(sea, &phase, &scb->datalen,
1393 				    &scb->data);
1394 			break;
1395 		case PH_MSGIN:
1396 			/* Multibyte messages should not be present here. */
1397 			len = 1;
1398 			data = &tmp;
1399 			sea_transfer_pio(sea, &phase, &len, &data);
1400 			/* scb->MessageIn = tmp; */
1401 
1402 			switch (tmp) {
1403 			case MSG_ABORT:
1404 				scb->flags = SCB_ABORTED;
1405 				printf("sea: command aborted by target\n");
1406 				CONTROL = BASE_CMD;
1407 				sea_done(sea, scb);
1408 				return;
1409 			case MSG_CMDCOMPLETE:
1410 				s = splbio();
1411 				sea->nexus = NULL;
1412 				splx(s);
1413 				sea->busy[scb->xs->xs_periph->periph_target] &=
1414 				    ~(1 << scb->xs->xs_periph->periph_lun);
1415 				CONTROL = BASE_CMD;
1416 				sea_done(sea, scb);
1417 				return;
1418 			case MSG_MESSAGE_REJECT:
1419 				printf("%s: message_reject received\n",
1420 				    sea->sc_dev.dv_xname);
1421 				break;
1422 			case MSG_DISCONNECT:
1423 				s = splbio();
1424 				TAILQ_INSERT_TAIL(&sea->nexus_list,
1425 				    scb, chain);
1426 				sea->nexus = NULL;
1427 				CONTROL = BASE_CMD;
1428 				splx(s);
1429 				return;
1430 			case MSG_SAVEDATAPOINTER:
1431 			case MSG_RESTOREPOINTERS:
1432 				/* save/restore of pointers are ignored */
1433 				break;
1434 			default:
1435 				/*
1436 				 * This should be handled in the pio data
1437 				 * transfer phase, as the ATN should be raised
1438 				 * before ACK goes false when rejecting a
1439 				 * message.
1440 				 */
1441 				printf("%s: unknown message in: %x\n",
1442 				    sea->sc_dev.dv_xname, tmp);
1443 				break;
1444 			} /* switch (tmp) */
1445 			break;
1446 		case PH_MSGOUT:
1447 			len = 1;
1448 			data = &msgout;
1449 			/* sea->last_message = msgout; */
1450 			sea_transfer_pio(sea, &phase, &len, &data);
1451 			if (msgout == MSG_ABORT) {
1452 				printf("%s: sent message abort to target\n",
1453 				    sea->sc_dev.dv_xname);
1454 				s = splbio();
1455 				sea->busy[scb->xs->xs_periph->periph_target] &=
1456 				    ~(1 << scb->xs->xs_periph->periph_lun);
1457 				sea->nexus = NULL;
1458 				scb->flags = SCB_ABORTED;
1459 				splx(s);
1460 				/* enable interrupt from scsi */
1461 				sea_done(sea, scb);
1462 				return;
1463 			}
1464 			msgout = MSG_NOOP;
1465 			break;
1466 		case PH_CMD:
1467 			len = scb->xs->cmdlen;
1468 			data = (char *) scb->xs->cmd;
1469 			sea_transfer_pio(sea, &phase, &len, &data);
1470 			break;
1471 		case PH_STAT:
1472 			len = 1;
1473 			data = &tmp;
1474 			sea_transfer_pio(sea, &phase, &len, &data);
1475 			scb->xs->status = tmp;
1476 			break;
1477 		default:
1478 			printf("sea: unknown phase\n");
1479 		} /* switch (phase) */
1480 	} /* for (...) */
1481 
1482 	/* If we get here we have got a timeout! */
1483 	printf("%s: timeout in data transfer\n", sea->sc_dev.dv_xname);
1484 	scb->flags = SCB_TIMEOUT;
1485 	/* XXX Should I clear scsi-bus state? */
1486 	sea_done(sea, scb);
1487 }
1488