xref: /netbsd-src/sys/dev/isa/seagate.c (revision 89c5a767f8fc7a4633b2d409966e2becbb98ff92)
1 /*	$NetBSD: seagate.c,v 1.34 1999/09/30 23:04:41 thorpej 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/types.h>
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/kernel.h>
71 #include <sys/errno.h>
72 #include <sys/ioctl.h>
73 #include <sys/device.h>
74 #include <sys/buf.h>
75 #include <sys/proc.h>
76 #include <sys/user.h>
77 #include <sys/queue.h>
78 #include <sys/malloc.h>
79 
80 #include <machine/intr.h>
81 #include <machine/pio.h>
82 
83 #include <dev/scsipi/scsi_all.h>
84 #include <dev/scsipi/scsipi_all.h>
85 #include <dev/scsipi/scsi_message.h>
86 #include <dev/scsipi/scsiconf.h>
87 
88 #include <dev/isa/isareg.h>
89 #include <dev/isa/isavar.h>	/* XXX USES ISA HOLE DIRECTLY */
90 
91 #define	SEA_SCB_MAX	32	/* allow maximally 8 scsi control blocks */
92 #define SCB_TABLE_SIZE	8	/* start with 8 scb entries in table */
93 #define BLOCK_SIZE	512	/* size of READ/WRITE areas on SCSI card */
94 
95 /*
96  * defining SEA_BLINDTRANSFER will make DATA IN and DATA OUT to be done with
97  * blind transfers, i.e. no check is done for scsi phase changes. This will
98  * result in data loss if the scsi device does not send its data using
99  * BLOCK_SIZE bytes at a time.
100  * If SEA_BLINDTRANSFER defined and SEA_ASSEMBLER also defined will result in
101  * the use of blind transfers coded in assembler. SEA_ASSEMBLER is no good
102  * without SEA_BLINDTRANSFER defined.
103  */
104 #define	SEA_BLINDTRANSFER	/* do blind transfers */
105 #define	SEA_ASSEMBLER		/* Use assembly code for fast transfers */
106 
107 /*
108  * defining SEA_NOMSGS causes messages not to be used (thereby disabling
109  * disconnects)
110  */
111 #undef	SEA_NOMSGS
112 
113 /*
114  * defining SEA_NODATAOUT makes dataout phase being aborted
115  */
116 #undef	SEA_NODATAOUT
117 
118 /* Debugging definitions. Should not be used unless you want a lot of
119    printouts even under normal conditions */
120 
121 #undef	SEA_DEBUGQUEUE		/* Display info about queue-lengths */
122 
123 /******************************* board definitions **************************/
124 /*
125  * CONTROL defines
126  */
127 #define CMD_RST		0x01		/* scsi reset */
128 #define CMD_SEL		0x02		/* scsi select */
129 #define CMD_BSY		0x04		/* scsi busy */
130 #define	CMD_ATTN	0x08		/* scsi attention */
131 #define CMD_START_ARB	0x10		/* start arbitration bit */
132 #define	CMD_EN_PARITY	0x20		/* enable scsi parity generation */
133 #define CMD_INTR	0x40		/* enable scsi interrupts */
134 #define CMD_DRVR_ENABLE	0x80		/* scsi enable */
135 
136 /*
137  * STATUS
138  */
139 #define STAT_BSY	0x01		/* scsi busy */
140 #define STAT_MSG	0x02		/* scsi msg */
141 #define STAT_IO		0x04		/* scsi I/O */
142 #define STAT_CD		0x08		/* scsi C/D */
143 #define STAT_REQ	0x10		/* scsi req */
144 #define STAT_SEL	0x20		/* scsi select */
145 #define STAT_PARITY	0x40		/* parity error bit */
146 #define STAT_ARB_CMPL	0x80		/* arbitration complete bit */
147 
148 /*
149  * REQUESTS
150  */
151 #define PH_DATAOUT	(0)
152 #define PH_DATAIN	(STAT_IO)
153 #define PH_CMD		(STAT_CD)
154 #define PH_STAT		(STAT_CD | STAT_IO)
155 #define PH_MSGOUT	(STAT_MSG | STAT_CD)
156 #define PH_MSGIN	(STAT_MSG | STAT_CD | STAT_IO)
157 
158 #define PH_MASK		(STAT_MSG | STAT_CD | STAT_IO)
159 
160 #define PH_INVALID	0xff
161 
162 #define SEA_RAMOFFSET	0x00001800
163 
164 #define BASE_CMD	(CMD_INTR | CMD_EN_PARITY)
165 
166 #define	SEAGATE		1	/* Seagate ST0[12] */
167 #define	FDOMAIN		2	/* Future Domain TMC-{885,950} */
168 #define	FDOMAIN840	3	/* Future Domain TMC-{84[01],88[01]} */
169 
170 /******************************************************************************/
171 
172 /* scsi control block used to keep info about a scsi command */
173 struct sea_scb {
174         u_char *data;			/* position in data buffer so far */
175 	int datalen;			/* bytes remaining to transfer */
176 	TAILQ_ENTRY(sea_scb) chain;
177 	struct scsipi_xfer *xs;		/* the scsipi_xfer for this cmd */
178 	int flags;			/* status of the instruction */
179 #define	SCB_FREE	0
180 #define	SCB_ACTIVE	1
181 #define SCB_ABORTED	2
182 #define SCB_TIMEOUT	4
183 #define SCB_ERROR	8
184 };
185 
186 /*
187  * data structure describing current status of the scsi bus. One for each
188  * controller card.
189  */
190 struct sea_softc {
191 	struct device sc_dev;
192 	void *sc_ih;
193 
194 	int type;			/* board type */
195 	caddr_t	maddr;			/* Base address for card */
196 	caddr_t	maddr_cr_sr;		/* Address of control and status reg */
197 	caddr_t	maddr_dr;		/* Address of data register */
198 
199 	struct scsipi_link sc_link;	/* prototype for subdevs */
200 	struct scsipi_adapter sc_adapter;
201 	TAILQ_HEAD(, sea_scb) free_list, ready_list, nexus_list;
202 	struct sea_scb *nexus;		/* currently connected command */
203 	int numscbs;			/* number of scsi control blocks */
204 	struct sea_scb scb[SCB_TABLE_SIZE];
205 
206 	int our_id;			/* our scsi id */
207 	u_char our_id_mask;
208 	volatile u_char busy[8];	/* index=target, bit=lun, Keep track of
209 					   busy luns at device target */
210 };
211 
212 /* flag showing if main routine is running. */
213 static volatile int main_running = 0;
214 
215 #define	STATUS	(*(volatile u_char *)sea->maddr_cr_sr)
216 #define CONTROL	STATUS
217 #define DATA	(*(volatile u_char *)sea->maddr_dr)
218 
219 /*
220  * These are "special" values for the tag parameter passed to sea_select
221  * Not implemented right now.
222  */
223 #define TAG_NEXT	-1	/* Use next free tag */
224 #define TAG_NONE	-2	/*
225 				 * Establish I_T_L nexus instead of I_T_L_Q
226 				 * even on SCSI-II devices.
227 				 */
228 
229 typedef struct {
230 	char *signature;
231 	int offset, length;
232 	int type;
233 } BiosSignature;
234 
235 /*
236  * Signatures for automatic recognition of board type
237  */
238 static const BiosSignature signatures[] = {
239 {"ST01 v1.7  (C) Copyright 1987 Seagate", 15, 37, SEAGATE},
240 {"SCSI BIOS 2.00  (C) Copyright 1987 Seagate", 15, 40, SEAGATE},
241 
242 /*
243  * The following two lines are NOT mistakes. One detects ROM revision
244  * 3.0.0, the other 3.2. Since seagate has only one type of SCSI adapter,
245  * and this is not going to change, the "SEAGATE" and "SCSI" together
246  * are probably "good enough"
247  */
248 {"SEAGATE SCSI BIOS ", 16, 17, SEAGATE},
249 {"SEAGATE SCSI BIOS ", 17, 17, SEAGATE},
250 
251 /*
252  * However, future domain makes several incompatible SCSI boards, so specific
253  * signatures must be used.
254  */
255 {"FUTURE DOMAIN CORP. (C) 1986-1989 V5.0C2/14/89", 5, 45, FDOMAIN},
256 {"FUTURE DOMAIN CORP. (C) 1986-1989 V6.0A7/28/89", 5, 46, FDOMAIN},
257 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0105/31/90",5, 47, FDOMAIN},
258 {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0209/18/90",5, 47, FDOMAIN},
259 {"FUTURE DOMAIN CORP. (C) 1986-1990 V7.009/18/90", 5, 46, FDOMAIN},
260 {"FUTURE DOMAIN CORP. (C) 1992 V8.00.004/02/92",   5, 44, FDOMAIN},
261 {"FUTURE DOMAIN TMC-950",			   5, 21, FDOMAIN},
262 };
263 
264 #define	nsignatures	(sizeof(signatures) / sizeof(signatures[0]))
265 
266 #ifdef notdef
267 static const char *bases[] = {
268 	(char *) 0xc8000, (char *) 0xca000, (char *) 0xcc000,
269 	(char *) 0xce000, (char *) 0xdc000, (char *) 0xde000
270 };
271 
272 #define	nbases		(sizeof(bases) / sizeof(bases[0]))
273 #endif
274 
275 int seaintr __P((void *));
276 int sea_scsi_cmd __P((struct scsipi_xfer *));
277 void sea_timeout __P((void *));
278 void sea_done __P((struct sea_softc *, struct sea_scb *));
279 struct sea_scb *sea_get_scb __P((struct sea_softc *, int));
280 void sea_free_scb __P((struct sea_softc *, struct sea_scb *, int));
281 static void sea_main __P((void));
282 static void sea_information_transfer __P((struct sea_softc *));
283 int sea_poll __P((struct sea_softc *, struct scsipi_xfer *, int));
284 void sea_init __P((struct sea_softc *));
285 void sea_send_scb __P((struct sea_softc *sea, struct sea_scb *scb));
286 void sea_reselect __P((struct sea_softc *sea));
287 int sea_select __P((struct sea_softc *sea, struct sea_scb *scb));
288 int sea_transfer_pio __P((struct sea_softc *sea, u_char *phase,
289     int *count, u_char **data));
290 int sea_abort __P((struct sea_softc *, struct sea_scb *scb));
291 
292 /* the below structure is so we have a default dev struct for our link struct */
293 struct scsipi_device sea_dev = {
294 	NULL,		/* use default error handler */
295 	NULL,		/* have a queue, served by this */
296 	NULL,		/* have no async handler */
297 	NULL,		/* Use default 'done' routine */
298 };
299 
300 int	seaprobe __P((struct device *, struct cfdata *, void *));
301 void	seaattach __P((struct device *, struct device *, void *));
302 
303 struct cfattach sea_ca = {
304 	sizeof(struct sea_softc), seaprobe, seaattach
305 };
306 
307 extern struct cfdriver sea_cd;
308 
309 #ifdef SEA_DEBUGQUEUE
310 void
311 sea_queue_length(sea)
312 	struct sea_softc *sea;
313 {
314 	struct sea_scb *scb;
315 	int connected, issued, disconnected;
316 
317 	connected = sea->nexus ? 1 : 0;
318 	for (scb = sea->ready_list.tqh_first, issued = 0; scb;
319 	    scb = scb->chain.tqe_next, issued++);
320 	for (scb = sea->nexus_list.tqh_first, disconnected = 0; scb;
321 	    scb = scb->chain.tqe_next, disconnected++);
322 	printf("%s: length: %d/%d/%d\n", sea->sc_dev.dv_xname, connected,
323 	    issued, disconnected);
324 }
325 #endif
326 
327 /*
328  * Check if the device can be found at the port given and if so, detect the
329  * type the type of board.  Set it up ready for further work. Takes the isa_dev
330  * structure from autoconf as an argument.
331  * Returns 1 if card recognized, 0 if errors.
332  */
333 int
334 seaprobe(parent, match, aux)
335 	struct device *parent;
336 	struct cfdata *match;
337 	void *aux;
338 {
339 	struct isa_attach_args *ia = aux;
340 	int i, type = 0;
341 	caddr_t maddr;
342 
343 	/*
344 	 * Could try to find a board by looking through all possible addresses.
345 	 * This is not done the right way now, because I have not found a way
346 	 * to get a boards virtual memory address given its physical.  There is
347 	 * a function that returns the physical address for a given virtual
348 	 * address, but not the other way around.
349 	 */
350 
351 	if (ia->ia_maddr == MADDRUNK) {
352 		/* XXX */
353 		return 0;
354 	} else
355 		maddr = ISA_HOLE_VADDR(ia->ia_maddr);
356 
357 	/* check board type */	/* No way to define this through config */
358 	for (i = 0; i < nsignatures; i++)
359 		if (!bcmp(maddr + signatures[i].offset,
360 		    signatures[i].signature, signatures[i].length)) {
361 			type = signatures[i].type;
362 			break;
363 		}
364 
365 	/* Find controller and data memory addresses */
366 	switch (type) {
367 	case SEAGATE:
368 	case FDOMAIN840:
369 	case FDOMAIN:
370 		break;
371 	default:
372 #ifdef DEBUG
373 		printf("seaprobe: board type unknown at address 0x%x\n",
374 		    ia->ia_maddr);
375 #endif
376 		return 0;
377 	}
378 
379 	ia->ia_drq = DRQUNK;
380 	ia->ia_msize = 0x2000;
381 	ia->ia_iosize = 0;
382 	return 1;
383 }
384 
385 /*
386  * Attach all sub-devices we can find
387  */
388 void
389 seaattach(parent, self, aux)
390 	struct device *parent, *self;
391 	void *aux;
392 {
393 	struct isa_attach_args *ia = aux;
394 	struct sea_softc *sea = (void *)self;
395 	int i;
396 
397 	sea->maddr = ISA_HOLE_VADDR(ia->ia_maddr);
398 
399 	/* check board type */	/* No way to define this through config */
400 	for (i = 0; i < nsignatures; i++)
401 		if (!bcmp(sea->maddr + signatures[i].offset,
402 		    signatures[i].signature, signatures[i].length)) {
403 			sea->type = signatures[i].type;
404 			break;
405 		}
406 
407 	/* Find controller and data memory addresses */
408 	switch (sea->type) {
409 	case SEAGATE:
410 	case FDOMAIN840:
411 		sea->maddr_cr_sr =
412 		    (void *) (((u_char *)sea->maddr) + 0x1a00);
413 		sea->maddr_dr =
414 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
415 		break;
416 	case FDOMAIN:
417 		sea->maddr_cr_sr =
418 		    (void *) (((u_char *)sea->maddr) + 0x1c00);
419 		sea->maddr_dr =
420 		    (void *) (((u_char *)sea->maddr) + 0x1e00);
421 		break;
422 	default:
423 #ifdef DEBUG
424 		printf("%s: board type unknown at address 0x%x\n",
425 		    sea->sc_dev.dv_xname, ia->ia_maddr);
426 #endif
427 		return;
428 	}
429 
430 	/* Test controller RAM (works the same way on future domain cards?) */
431 	*((u_char *)sea->maddr + SEA_RAMOFFSET) = 0xa5;
432 	*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) = 0x5a;
433 
434 	if ((*((u_char *)sea->maddr + SEA_RAMOFFSET) != 0xa5) ||
435 	    (*((u_char *)sea->maddr + SEA_RAMOFFSET + 1) != 0x5a)) {
436 		printf("%s: board RAM failure\n", sea->sc_dev.dv_xname);
437 		return;
438 	}
439 
440 	sea_init(sea);
441 
442 	/*
443 	 * Fill in the adapter.
444 	 */
445 	sea->sc_adapter.scsipi_cmd = sea_scsi_cmd;
446 	sea->sc_adapter.scsipi_minphys = minphys;
447 
448 	/*
449 	 * fill in the prototype scsipi_link.
450 	 */
451 	sea->sc_link.scsipi_scsi.channel = SCSI_CHANNEL_ONLY_ONE;
452 	sea->sc_link.adapter_softc = sea;
453 	sea->sc_link.scsipi_scsi.adapter_target = sea->our_id;
454 	sea->sc_link.adapter = &sea->sc_adapter;
455 	sea->sc_link.device = &sea_dev;
456 	sea->sc_link.openings = 1;
457 	sea->sc_link.scsipi_scsi.max_target = 7;
458 	sea->sc_link.scsipi_scsi.max_lun = 7;
459 	sea->sc_link.type = BUS_SCSI;
460 
461 	printf("\n");
462 
463 	sea->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq, IST_EDGE,
464 	    IPL_BIO, seaintr, sea);
465 
466 	/*
467 	 * ask the adapter what subunits are present
468 	 */
469 	config_found(self, &sea->sc_link, scsiprint);
470 }
471 
472 /*
473  * Catch an interrupt from the adaptor
474  */
475 int
476 seaintr(arg)
477 	void *arg;
478 {
479 	struct sea_softc *sea = arg;
480 
481 #ifdef DEBUG	/* extra overhead, and only needed for intr debugging */
482 	if ((STATUS & STAT_PARITY) == 0 &&
483 	    (STATUS & (STAT_SEL | STAT_IO)) != (STAT_SEL | STAT_IO))
484 		return 0;
485 #endif
486 
487 loop:
488 	/* dispatch to appropriate routine if found and done=0 */
489 	/* should check to see that this card really caused the interrupt */
490 
491 	if (STATUS & STAT_PARITY) {
492 		/* Parity error interrupt */
493 		printf("%s: parity error\n", sea->sc_dev.dv_xname);
494 		return 1;
495 	}
496 
497 	if ((STATUS & (STAT_SEL | STAT_IO)) == (STAT_SEL | STAT_IO)) {
498 		/* Reselect interrupt */
499 		sea_reselect(sea);
500 		if (!main_running)
501 			sea_main();
502 		goto loop;
503 	}
504 
505 	return 1;
506 }
507 
508 /*
509  * Setup data structures, and reset the board and the SCSI bus.
510  */
511 void
512 sea_init(sea)
513 	struct sea_softc *sea;
514 {
515 	int i;
516 
517 	/* Reset the scsi bus (I don't know if this is needed */
518 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_RST;
519 	delay(25);	/* hold reset for at least 25 microseconds */
520 	CONTROL = BASE_CMD;
521 	delay(10); 	/* wait a Bus Clear Delay (800 ns + bus free delay (800 ns) */
522 
523 	/* Set our id (don't know anything about this) */
524 	switch (sea->type) {
525 	case SEAGATE:
526 		sea->our_id = 7;
527 		break;
528 	case FDOMAIN:
529 	case FDOMAIN840:
530 		sea->our_id = 6;
531 		break;
532 	}
533 	sea->our_id_mask = 1 << sea->our_id;
534 
535 	/* init fields used by our routines */
536 	sea->nexus = 0;
537 	TAILQ_INIT(&sea->ready_list);
538 	TAILQ_INIT(&sea->nexus_list);
539 	TAILQ_INIT(&sea->free_list);
540 	for (i = 0; i < 8; i++)
541 		sea->busy[i] = 0x00;
542 
543 	/* link up the free list of scbs */
544 	sea->numscbs = SCB_TABLE_SIZE;
545 	for (i = 0; i < SCB_TABLE_SIZE; i++) {
546 		TAILQ_INSERT_TAIL(&sea->free_list, &sea->scb[i], chain);
547 	}
548 }
549 
550 /*
551  * start a scsi operation given the command and the data address. Also needs
552  * the unit, target and lu.
553  */
554 int
555 sea_scsi_cmd(xs)
556 	struct scsipi_xfer *xs;
557 {
558 	struct scsipi_link *sc_link = xs->sc_link;
559 	struct sea_softc *sea = sc_link->adapter_softc;
560 	struct sea_scb *scb;
561 	int flags;
562 	int s;
563 
564 	SC_DEBUG(sc_link, SDEV_DB2, ("sea_scsi_cmd\n"));
565 
566 	flags = xs->xs_control;
567 	if ((scb = sea_get_scb(sea, flags)) == NULL) {
568 		xs->error = XS_DRIVER_STUFFUP;
569 		return TRY_AGAIN_LATER;
570 	}
571 	scb->flags = SCB_ACTIVE;
572 	scb->xs = xs;
573 
574 	if (flags & XS_CTL_RESET) {
575 		/*
576 		 * Try to send a reset command to the card.
577 		 * XXX Not implemented.
578 		 */
579 		printf("%s: resetting\n", sea->sc_dev.dv_xname);
580 		xs->error = XS_DRIVER_STUFFUP;
581 		return COMPLETE;
582 	}
583 
584 	/*
585 	 * Put all the arguments for the xfer in the scb
586 	 */
587 	scb->datalen = xs->datalen;
588 	scb->data = xs->data;
589 
590 #ifdef SEA_DEBUGQUEUE
591 	sea_queue_length(sea);
592 #endif
593 
594 	s = splbio();
595 
596 	sea_send_scb(sea, scb);
597 
598 	/*
599 	 * Usually return SUCCESSFULLY QUEUED
600 	 */
601 	if ((flags & XS_CTL_POLL) == 0) {
602 		timeout(sea_timeout, scb, (xs->timeout * hz) / 1000);
603 		splx(s);
604 		return SUCCESSFULLY_QUEUED;
605 	}
606 
607 	splx(s);
608 
609 	/*
610 	 * If we can't use interrupts, poll on completion
611 	 */
612 	if (sea_poll(sea, xs, xs->timeout)) {
613 		sea_timeout(scb);
614 		if (sea_poll(sea, xs, 2000))
615 			sea_timeout(scb);
616 	}
617 	return COMPLETE;
618 }
619 
620 /*
621  * Get a free scb. If there are none, see if we can allocate a new one.  If so,
622  * put it in the hash table too; otherwise return an error or sleep.
623  */
624 struct sea_scb *
625 sea_get_scb(sea, flags)
626 	struct sea_softc *sea;
627 	int flags;
628 {
629 	int s;
630 	struct sea_scb *scb;
631 
632 	s = splbio();
633 
634 	/*
635 	 * If we can and have to, sleep waiting for one to come free
636 	 * but only if we can't allocate a new one.
637 	 */
638 	for (;;) {
639 		scb = sea->free_list.tqh_first;
640 		if (scb) {
641 			TAILQ_REMOVE(&sea->free_list, scb, chain);
642 			break;
643 		}
644 		if (sea->numscbs < SEA_SCB_MAX) {
645 			scb = (struct sea_scb *) malloc(sizeof(struct sea_scb),
646 			    M_TEMP, M_NOWAIT);
647 			if (scb) {
648 				bzero(scb, sizeof(struct sea_scb));
649 				sea->numscbs++;
650 			} else
651 				printf("%s: can't malloc scb\n",
652 				    sea->sc_dev.dv_xname);
653 			break;
654 		}
655 		if ((flags & XS_CTL_NOSLEEP) != 0)
656 			break;
657 		tsleep(&sea->free_list, PRIBIO, "seascb", 0);
658 	}
659 
660 	splx(s);
661 	return scb;
662 }
663 
664 /*
665  * Try to send this command to the board. Because this board does not use any
666  * mailboxes, this routine simply adds the command to the queue held by the
667  * sea_softc structure.
668  * A check is done to see if the command contains a REQUEST_SENSE command, and
669  * if so the command is put first in the queue, otherwise the command is added
670  * to the end of the queue. ?? Not correct ??
671  */
672 void
673 sea_send_scb(sea, scb)
674 	struct sea_softc *sea;
675 	struct sea_scb *scb;
676 {
677 
678 	TAILQ_INSERT_TAIL(&sea->ready_list, scb, chain);
679 	/* Try to do some work on the card. */
680 	if (!main_running)
681 		sea_main();
682 }
683 
684 /*
685  * Coroutine that runs as long as more work can be done on the seagate host
686  * adapter in a system.  Both sea_scsi_cmd and sea_intr will try to start it in
687  * case it is not running.
688  */
689 void
690 sea_main()
691 {
692 	struct sea_softc *sea;
693 	struct sea_scb *scb;
694 	int done;
695 	int unit;
696 	int s;
697 
698 	main_running = 1;
699 
700 	/*
701 	 * This should not be run with interrupts disabled, but use the splx
702 	 * code instead.
703 	 */
704 loop:
705 	done = 1;
706 	for (unit = 0; unit < sea_cd.cd_ndevs; unit++) {
707 		sea = sea_cd.cd_devs[unit];
708 		if (!sea)
709 			continue;
710 		s = splbio();
711 		if (!sea->nexus) {
712 			/*
713 			 * Search through the ready_list for a command
714 			 * destined for a target that's not busy.
715 			 */
716 			for (scb = sea->ready_list.tqh_first; scb;
717 			    scb = scb->chain.tqe_next) {
718 				if (!(sea->busy[scb->xs->sc_link->scsipi_scsi.target] &
719 				    (1 << scb->xs->sc_link->scsipi_scsi.lun))) {
720 					TAILQ_REMOVE(&sea->ready_list, scb,
721 					    chain);
722 
723 					/* Re-enable interrupts. */
724 					splx(s);
725 
726 					/*
727 					 * Attempt to establish an I_T_L nexus.
728 					 * On success, sea->nexus is set.
729 					 * On failure, we must add the command
730 					 * back to the issue queue so we can
731 					 * keep trying.
732 					 */
733 
734 					/*
735 					 * REQUEST_SENSE commands are issued
736 					 * without tagged queueing, even on
737 					 * SCSI-II devices because the
738 					 * contingent alligence condition
739 					 * exists for the entire unit.
740 					 */
741 
742 					/*
743 					 * First check that if any device has
744 					 * tried a reconnect while we have done
745 					 * other things with interrupts
746 					 * disabled.
747 					 */
748 
749 					if ((STATUS & (STAT_SEL | STAT_IO)) ==
750 					    (STAT_SEL | STAT_IO)) {
751 						sea_reselect(sea);
752 						break;
753 					}
754 					if (sea_select(sea, scb)) {
755 						s = splbio();
756 						TAILQ_INSERT_HEAD(&sea->ready_list,
757 						    scb, chain);
758 						splx(s);
759 					} else
760 						break;
761 				} /* if target/lun is not busy */
762 			} /* for scb */
763 			if (!sea->nexus) {
764 				/* check for reselection phase */
765 				if ((STATUS & (STAT_SEL | STAT_IO)) ==
766 				    (STAT_SEL | STAT_IO)) {
767 					sea_reselect(sea);
768 				}
769 			}
770 		} /* if (!sea->nexus) */
771 
772 		splx(s);
773 		if (sea->nexus) {	/* we are connected. Do the task */
774 			sea_information_transfer(sea);
775 			done = 0;
776 		} else
777 			break;
778 	} /* for instance */
779 
780 	if (!done)
781 		goto loop;
782 
783 	main_running = 0;
784 }
785 
786 void
787 sea_free_scb(sea, scb, flags)
788 	struct sea_softc *sea;
789 	struct sea_scb *scb;
790 	int flags;
791 {
792 	int s;
793 
794 	s = splbio();
795 
796 	scb->flags = SCB_FREE;
797 	TAILQ_INSERT_HEAD(&sea->free_list, scb, chain);
798 
799 	/*
800 	 * If there were none, wake anybody waiting for one to come free,
801 	 * starting with queued entries.
802 	 */
803 	if (!scb->chain.tqe_next)
804 		wakeup((caddr_t)&sea->free_list);
805 
806 	splx(s);
807 }
808 
809 void
810 sea_timeout(arg)
811 	void *arg;
812 {
813 	struct sea_scb *scb = arg;
814 	struct scsipi_xfer *xs = scb->xs;
815 	struct scsipi_link *sc_link = xs->sc_link;
816 	struct sea_softc *sea = sc_link->adapter_softc;
817 	int s;
818 
819 	scsi_print_addr(sc_link);
820 	printf("timed out");
821 
822 	s = splbio();
823 
824 	/*
825 	 * If it has been through before, then
826 	 * a previous abort has failed, don't
827 	 * try abort again
828 	 */
829 	if (scb->flags & SCB_ABORTED) {
830 		/* abort timed out */
831 		printf(" AGAIN\n");
832 	 	scb->xs->retries = 0;
833 		scb->flags |= SCB_ABORTED;
834 		sea_done(sea, scb);
835 	} else {
836 		/* abort the operation that has timed out */
837 		printf("\n");
838 		scb->flags |= SCB_ABORTED;
839 		sea_abort(sea, scb);
840 		/* 2 secs for the abort */
841 		if ((xs->xs_control & XS_CTL_POLL) == 0)
842 			timeout(sea_timeout, scb, 2 * hz);
843 	}
844 
845 	splx(s);
846 }
847 
848 void
849 sea_reselect(sea)
850 	struct sea_softc *sea;
851 {
852 	u_char target_mask;
853 	int i;
854 	u_char lun, phase;
855 	u_char msg[3];
856 	int len;
857 	u_char *data;
858 	struct sea_scb *scb;
859 	int abort = 0;
860 
861 	if (!((target_mask = STATUS) & STAT_SEL)) {
862 		printf("%s: wrong state 0x%x\n", sea->sc_dev.dv_xname,
863 		    target_mask);
864 		return;
865 	}
866 
867 	/* wait for a device to win the reselection phase */
868 	/* signals this by asserting the I/O signal */
869 	for (i = 10; i && (STATUS & (STAT_SEL | STAT_IO | STAT_BSY)) !=
870 	    (STAT_SEL | STAT_IO | 0); i--);
871 	/* !! Check for timeout here */
872 	/* the data bus contains original initiator id ORed with target id */
873 	target_mask = DATA;
874 	/* see that we really are the initiator */
875 	if (!(target_mask & sea->our_id_mask)) {
876 		printf("%s: polled reselection was not for me: 0x%x\n",
877 		    sea->sc_dev.dv_xname, target_mask);
878 		return;
879 	}
880 	/* find target who won */
881 	target_mask &= ~sea->our_id_mask;
882 	/* host responds by asserting the BSY signal */
883 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY;
884 	/* target should respond by deasserting the SEL signal */
885 	for (i = 50000; i && (STATUS & STAT_SEL); i++);
886 	/* remove the busy status */
887 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
888 	/* we are connected. Now we wait for the MSGIN condition */
889 	for (i = 50000; i && !(STATUS & STAT_REQ); i--);
890 	/* !! Add timeout check here */
891 	/* hope we get an IDENTIFY message */
892 	len = 3;
893 	data = msg;
894 	phase = PH_MSGIN;
895 	sea_transfer_pio(sea, &phase, &len, &data);
896 
897 	if (MSG_ISIDENTIFY(msg[0])) {
898 		printf("%s: expecting IDENTIFY message, got 0x%x\n",
899 		    sea->sc_dev.dv_xname, msg[0]);
900 		abort = 1;
901 		scb = NULL;
902 	} else {
903 		lun = msg[0] & 0x07;
904 
905 		/*
906 		 * Find the command corresponding to the I_T_L or I_T_L_Q nexus
907 		 * we just reestablished, and remove it from the disconnected
908 		 * queue.
909 		 */
910 		for (scb = sea->nexus_list.tqh_first; scb;
911 		    scb = scb->chain.tqe_next)
912 			if (target_mask == (1 << scb->xs->sc_link->scsipi_scsi.target) &&
913 			    lun == scb->xs->sc_link->scsipi_scsi.lun) {
914 				TAILQ_REMOVE(&sea->nexus_list, scb,
915 				    chain);
916 				break;
917 			}
918 		if (!scb) {
919 			printf("%s: target %02x lun %d not disconnected\n",
920 			    sea->sc_dev.dv_xname, target_mask, lun);
921 			/*
922 			 * Since we have an established nexus that we can't do
923 			 * anything with, we must abort it.
924 			 */
925 			abort = 1;
926 		}
927 	}
928 
929 	if (abort) {
930 		msg[0] = MSG_ABORT;
931 		len = 1;
932 		data = msg;
933 		phase = PH_MSGOUT;
934 		CONTROL = BASE_CMD | CMD_ATTN;
935 		sea_transfer_pio(sea, &phase, &len, &data);
936 	} else
937 		sea->nexus = scb;
938 
939 	return;
940 }
941 
942 /*
943  * Transfer data in given phase using polled I/O.
944  */
945 int
946 sea_transfer_pio(sea, phase, count, data)
947 	struct sea_softc *sea;
948 	u_char *phase;
949 	int *count;
950 	u_char **data;
951 {
952 	register u_char p = *phase, tmp;
953 	register int c = *count;
954 	register u_char *d = *data;
955 	int timeout;
956 
957 	do {
958 		/*
959 		 * Wait for assertion of REQ, after which the phase bits will
960 		 * be valid.
961 		 */
962 		for (timeout = 0; timeout < 50000; timeout++)
963 			if ((tmp = STATUS) & STAT_REQ)
964 				break;
965 		if (!(tmp & STAT_REQ)) {
966 			printf("%s: timeout waiting for STAT_REQ\n",
967 			    sea->sc_dev.dv_xname);
968 			break;
969 		}
970 
971 		/*
972 		 * Check for phase mismatch.  Reached if the target decides
973 		 * that it has finished the transfer.
974 		 */
975 		if (sea->type == FDOMAIN840)
976 			tmp = ((tmp & 0x08) >> 2) |
977 			      ((tmp & 0x02) << 2) |
978 			       (tmp & 0xf5);
979 		if ((tmp & PH_MASK) != p)
980 			break;
981 
982 		/* Do actual transfer from SCSI bus to/from memory. */
983 		if (!(p & STAT_IO))
984 			DATA = *d;
985 		else
986 			*d = DATA;
987 		++d;
988 
989 		/*
990 		 * The SCSI standard suggests that in MSGOUT phase, the
991 		 * initiator should drop ATN on the last byte of the message
992 		 * phase after REQ has been asserted for the handshake but
993 		 * before the initiator raises ACK.
994 		 * Don't know how to accomplish this on the ST01/02.
995 		 */
996 
997 #if 0
998 		/*
999 		 * XXX
1000 		 * The st01 code doesn't wait for STAT_REQ to be deasserted.
1001 		 * Is this ok?
1002 		 */
1003 		for (timeout = 0; timeout < 200000L; timeout++)
1004 			if (!(STATUS & STAT_REQ))
1005 				break;
1006 		if (STATUS & STAT_REQ)
1007 			printf("%s: timeout on wait for !STAT_REQ",
1008 			    sea->sc_dev.dv_xname);
1009 #endif
1010 	} while (--c);
1011 
1012 	*count = c;
1013 	*data = d;
1014 	tmp = STATUS;
1015 	if (tmp & STAT_REQ)
1016 		*phase = tmp & PH_MASK;
1017 	else
1018 		*phase = PH_INVALID;
1019 
1020 	if (c && (*phase != p))
1021 		return -1;
1022 	return 0;
1023 }
1024 
1025 /*
1026  * Establish I_T_L or I_T_L_Q nexus for new or existing command including
1027  * ARBITRATION, SELECTION, and initial message out for IDENTIFY and queue
1028  * messages.  Return -1 if selection could not execute for some reason, 0 if
1029  * selection succeded or failed because the target did not respond.
1030  */
1031 int
1032 sea_select(sea, scb)
1033 	struct sea_softc *sea;
1034 	struct sea_scb *scb;
1035 {
1036 	u_char msg[3], phase;
1037 	u_char *data;
1038 	int len;
1039 	int timeout;
1040 
1041 	CONTROL = BASE_CMD;
1042 	DATA = sea->our_id_mask;
1043 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_START_ARB;
1044 
1045 	/* wait for arbitration to complete */
1046 	for (timeout = 0; timeout < 3000000L; timeout++)
1047 		if (STATUS & STAT_ARB_CMPL)
1048 			break;
1049 	if (!(STATUS & STAT_ARB_CMPL)) {
1050 		if (STATUS & STAT_SEL) {
1051 			printf("%s: arbitration lost\n", sea->sc_dev.dv_xname);
1052 			scb->flags |= SCB_ERROR;
1053 		} else {
1054 			printf("%s: arbitration timeout\n",
1055 			    sea->sc_dev.dv_xname);
1056 			scb->flags |= SCB_TIMEOUT;
1057 		}
1058 		CONTROL = BASE_CMD;
1059 		return -1;
1060 	}
1061 
1062 	delay(2);
1063 	DATA = (u_char)((1 << scb->xs->sc_link->scsipi_scsi.target) |
1064 		sea->our_id_mask);
1065 	CONTROL =
1066 #ifdef SEA_NOMSGS
1067 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL;
1068 #else
1069 	    (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_SEL | CMD_ATTN;
1070 #endif
1071 	delay(1);
1072 
1073 	/* wait for a bsy from target */
1074 	for (timeout = 0; timeout < 2000000L; timeout++)
1075 		if (STATUS & STAT_BSY)
1076 			break;
1077 	if (!(STATUS & STAT_BSY)) {
1078 		/* should return some error to the higher level driver */
1079 		CONTROL = BASE_CMD;
1080 		scb->flags |= SCB_TIMEOUT;
1081 		return 0;
1082 	}
1083 
1084 	/* Try to make the target to take a message from us */
1085 #ifdef SEA_NOMSGS
1086 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE;
1087 #else
1088 	CONTROL = (BASE_CMD & ~CMD_INTR) | CMD_DRVR_ENABLE | CMD_ATTN;
1089 #endif
1090 	delay(1);
1091 
1092 	/* should start a msg_out phase */
1093 	for (timeout = 0; timeout < 2000000L; timeout++)
1094 		if (STATUS & STAT_REQ)
1095 			break;
1096 	/* Remove ATN. */
1097 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1098 	if (!(STATUS & STAT_REQ)) {
1099 		/*
1100 		 * This should not be taken as an error, but more like an
1101 		 * unsupported feature!  Should set a flag indicating that the
1102 		 * target don't support messages, and continue without failure.
1103 		 * (THIS IS NOT AN ERROR!)
1104 		 */
1105 	} else {
1106 		msg[0] = MSG_IDENTIFY(scb->xs->sc_link->scsipi_scsi.lun, 1);
1107 		len = 1;
1108 		data = msg;
1109 		phase = PH_MSGOUT;
1110 		/* Should do test on result of sea_transfer_pio(). */
1111 		sea_transfer_pio(sea, &phase, &len, &data);
1112 	}
1113 	if (!(STATUS & STAT_BSY))
1114 		printf("%s: after successful arbitrate: no STAT_BSY!\n",
1115 		    sea->sc_dev.dv_xname);
1116 
1117 	sea->nexus = scb;
1118 	sea->busy[scb->xs->sc_link->scsipi_scsi.target] |=
1119 						1 << scb->xs->sc_link->scsipi_scsi.lun;
1120 	/* This assignment should depend on possibility to send a message to target. */
1121 	CONTROL = BASE_CMD | CMD_DRVR_ENABLE;
1122 	/* XXX Reset pointer in command? */
1123 	return 0;
1124 }
1125 
1126 /*
1127  * Send an abort to the target.  Return 1 success, 0 on failure.
1128  */
1129 int
1130 sea_abort(sea, scb)
1131 	struct sea_softc *sea;
1132 	struct sea_scb *scb;
1133 {
1134 	struct sea_scb *tmp;
1135 	u_char msg, phase, *msgptr;
1136 	int len;
1137 
1138 	/*
1139 	 * If the command hasn't been issued yet, we simply remove it from the
1140 	 * issue queue
1141 	 * XXX Could avoid this loop.
1142 	 */
1143 	for (tmp = sea->ready_list.tqh_first; tmp; tmp = tmp->chain.tqe_next)
1144 		if (scb == tmp) {
1145 			TAILQ_REMOVE(&sea->ready_list, scb, chain);
1146 			/* XXX Set some type of error result for operation. */
1147 			return 1;
1148 		}
1149 
1150 	/*
1151 	 * If any commands are connected, we're going to fail the abort and let
1152 	 * the high level SCSI driver retry at a later time or issue a reset.
1153 	 */
1154 	if (sea->nexus)
1155 		return 0;
1156 
1157 	/*
1158 	 * If the command is currently disconnected from the bus, and there are
1159 	 * no connected commands, we reconnect the I_T_L or I_T_L_Q nexus
1160 	 * associated with it, go into message out, and send an abort message.
1161 	 */
1162 	for (tmp = sea->nexus_list.tqh_first; tmp;
1163 	    tmp = tmp->chain.tqe_next)
1164 		if (scb == tmp) {
1165 			if (sea_select(sea, scb))
1166 				return 0;
1167 
1168 			msg = MSG_ABORT;
1169 			msgptr = &msg;
1170 			len = 1;
1171 			phase = PH_MSGOUT;
1172 			CONTROL = BASE_CMD | CMD_ATTN;
1173 			sea_transfer_pio(sea, &phase, &len, &msgptr);
1174 
1175 			for (tmp = sea->nexus_list.tqh_first; tmp;
1176 			    tmp = tmp->chain.tqe_next)
1177 				if (scb == tmp) {
1178 					TAILQ_REMOVE(&sea->nexus_list,
1179 					    scb, chain);
1180 					/* XXX Set some type of error result
1181 					   for the operation. */
1182 					return 1;
1183 				}
1184 		}
1185 
1186 	/* Command not found in any queue; race condition? */
1187 	return 1;
1188 }
1189 
1190 void
1191 sea_done(sea, scb)
1192 	struct sea_softc *sea;
1193 	struct sea_scb *scb;
1194 {
1195 	struct scsipi_xfer *xs = scb->xs;
1196 
1197 	untimeout(sea_timeout, scb);
1198 
1199 	xs->resid = scb->datalen;
1200 
1201 	/* XXXX need to get status */
1202 	if (scb->flags == SCB_ACTIVE) {
1203 		xs->resid = 0;
1204 	} else {
1205 		if (scb->flags & (SCB_TIMEOUT | SCB_ABORTED))
1206 			xs->error = XS_TIMEOUT;
1207 		if (scb->flags & SCB_ERROR)
1208 			xs->error = XS_DRIVER_STUFFUP;
1209 	}
1210 	xs->xs_status |= XS_STS_DONE;
1211 	sea_free_scb(sea, scb, xs->xs_control);
1212 	scsipi_done(xs);
1213 }
1214 
1215 /*
1216  * Wait for completion of command in polled mode.
1217  */
1218 int
1219 sea_poll(sea, xs, count)
1220 	struct sea_softc *sea;
1221 	struct scsipi_xfer *xs;
1222 	int count;
1223 {
1224 	int s;
1225 
1226 	while (count) {
1227 		/* try to do something */
1228 		s = splbio();
1229 		if (!main_running)
1230 			sea_main();
1231 		splx(s);
1232 		if (xs->xs_status & XS_STS_DONE)
1233 			return 0;
1234 		delay(1000);
1235 		count--;
1236 	}
1237 	return 1;
1238 }
1239 
1240 /*
1241  * Do the transfer.  We know we are connected.  Update the flags, and call
1242  * sea_done() when task accomplished.  Dialog controlled by the target.
1243  */
1244 void
1245 sea_information_transfer(sea)
1246 	struct sea_softc *sea;
1247 {
1248 	int timeout;
1249 	u_char msgout = MSG_NOOP;
1250 	int len;
1251 	int s;
1252 	u_char *data;
1253 	u_char phase, tmp, old_phase = PH_INVALID;
1254 	struct sea_scb *scb = sea->nexus;
1255 	int loop;
1256 
1257 	for (timeout = 0; timeout < 10000000L; timeout++) {
1258 		tmp = STATUS;
1259 		if (tmp & STAT_PARITY)
1260 			printf("%s: parity error detected\n",
1261 			    sea->sc_dev.dv_xname);
1262 		if (!(tmp & STAT_BSY)) {
1263 			for (loop = 0; loop < 20; loop++)
1264 				if ((tmp = STATUS) & STAT_BSY)
1265 					break;
1266 			if (!(tmp & STAT_BSY)) {
1267 				printf("%s: !STAT_BSY unit in data transfer!\n",
1268 				    sea->sc_dev.dv_xname);
1269 				s = splbio();
1270 				sea->nexus = NULL;
1271 				scb->flags = SCB_ERROR;
1272 				splx(s);
1273 				sea_done(sea, scb);
1274 				return;
1275 			}
1276 		}
1277 
1278 		/* we only have a valid SCSI phase when REQ is asserted */
1279 		if (!(tmp & STAT_REQ))
1280 			continue;
1281 
1282 		if (sea->type == FDOMAIN840)
1283 			tmp = ((tmp & 0x08) >> 2) |
1284 			      ((tmp & 0x02) << 2) |
1285 			       (tmp & 0xf5);
1286 		phase = tmp & PH_MASK;
1287 		if (phase != old_phase)
1288 			old_phase = phase;
1289 
1290 		switch (phase) {
1291 		case PH_DATAOUT:
1292 #ifdef SEA_NODATAOUT
1293 			printf("%s: SEA_NODATAOUT set, attempted DATAOUT aborted\n",
1294 			    sea->sc_dev.dv_xname);
1295 			msgout = MSG_ABORT;
1296 			CONTROL = BASE_CMD | CMD_ATTN;
1297 			break;
1298 #endif
1299 		case PH_DATAIN:
1300 			if (!scb->data)
1301 				printf("no data address!\n");
1302 #ifdef SEA_BLINDTRANSFER
1303 			if (scb->datalen && !(scb->datalen % BLOCK_SIZE)) {
1304 				while (scb->datalen) {
1305 					for (loop = 0; loop < 50000; loop++)
1306 						if ((tmp = STATUS) & STAT_REQ)
1307 							break;
1308 					if (!(tmp & STAT_REQ)) {
1309 						printf("%s: timeout waiting for STAT_REQ\n",
1310 						    sea->sc_dev.dv_xname);
1311 						/* XXX Do something? */
1312 					}
1313 					if (sea->type == FDOMAIN840)
1314 						tmp = ((tmp & 0x08) >> 2) |
1315 						      ((tmp & 0x02) << 2) |
1316 						       (tmp & 0xf5);
1317 					if ((tmp & PH_MASK) != phase)
1318 						break;
1319 					if (!(phase & STAT_IO)) {
1320 #ifdef SEA_ASSEMBLER
1321 						asm("shr $2, %%ecx\n\t\
1322 						    cld\n\t\
1323 						    rep\n\t\
1324 						    movsl" :
1325 						    "=S" (scb->data) :
1326 						    "0" (scb->data),
1327 						    "D" (sea->maddr_dr),
1328 						    "c" (BLOCK_SIZE) :
1329 						    "%ecx", "%edi");
1330 #else
1331 						for (count = 0;
1332 						    count < BLOCK_SIZE;
1333 						    count++)
1334 							DATA = *(scb->data++);
1335 #endif
1336 					} else {
1337 #ifdef SEA_ASSEMBLER
1338 						asm("shr $2, %%ecx\n\t\
1339 						    cld\n\t\
1340 						    rep\n\t\
1341 						    movsl" :
1342 						    "=D" (scb->data) :
1343 						    "S" (sea->maddr_dr),
1344 						    "0" (scb->data),
1345 						    "c" (BLOCK_SIZE) :
1346 						    "%ecx", "%esi");
1347 #else
1348 					        for (count = 0;
1349 						    count < BLOCK_SIZE;
1350 						    count++)
1351 							*(scb->data++) = DATA;
1352 #endif
1353 					}
1354 					scb->datalen -= BLOCK_SIZE;
1355 				}
1356 			}
1357 #endif
1358 			if (scb->datalen)
1359 				sea_transfer_pio(sea, &phase, &scb->datalen,
1360 				    &scb->data);
1361 			break;
1362 		case PH_MSGIN:
1363 			/* Multibyte messages should not be present here. */
1364 			len = 1;
1365 			data = &tmp;
1366 			sea_transfer_pio(sea, &phase, &len, &data);
1367 			/* scb->MessageIn = tmp; */
1368 
1369 			switch (tmp) {
1370 			case MSG_ABORT:
1371 				scb->flags = SCB_ABORTED;
1372 				printf("sea: command aborted by target\n");
1373 				CONTROL = BASE_CMD;
1374 				sea_done(sea, scb);
1375 				return;
1376 			case MSG_CMDCOMPLETE:
1377 				s = splbio();
1378 				sea->nexus = NULL;
1379 				splx(s);
1380 				sea->busy[scb->xs->sc_link->scsipi_scsi.target] &=
1381 				    ~(1 << scb->xs->sc_link->scsipi_scsi.lun);
1382 				CONTROL = BASE_CMD;
1383 				sea_done(sea, scb);
1384 				return;
1385 			case MSG_MESSAGE_REJECT:
1386 				printf("%s: message_reject recieved\n",
1387 				    sea->sc_dev.dv_xname);
1388 				break;
1389 			case MSG_DISCONNECT:
1390 				s = splbio();
1391 				TAILQ_INSERT_TAIL(&sea->nexus_list,
1392 				    scb, chain);
1393 				sea->nexus = NULL;
1394 				CONTROL = BASE_CMD;
1395 				splx(s);
1396 				return;
1397 			case MSG_SAVEDATAPOINTER:
1398 			case MSG_RESTOREPOINTERS:
1399 				/* save/restore of pointers are ignored */
1400 				break;
1401 			default:
1402 				/*
1403 				 * This should be handled in the pio data
1404 				 * transfer phase, as the ATN should be raised
1405 				 * before ACK goes false when rejecting a
1406 				 * message.
1407 				 */
1408 				printf("%s: unknown message in: %x\n",
1409 				    sea->sc_dev.dv_xname, tmp);
1410 				break;
1411 			} /* switch (tmp) */
1412 			break;
1413 		case PH_MSGOUT:
1414 			len = 1;
1415 			data = &msgout;
1416 			/* sea->last_message = msgout; */
1417 			sea_transfer_pio(sea, &phase, &len, &data);
1418 			if (msgout == MSG_ABORT) {
1419 				printf("%s: sent message abort to target\n",
1420 				    sea->sc_dev.dv_xname);
1421 				s = splbio();
1422 				sea->busy[scb->xs->sc_link->scsipi_scsi.target] &=
1423 				    ~(1 << scb->xs->sc_link->scsipi_scsi.lun);
1424 				sea->nexus = NULL;
1425 				scb->flags = SCB_ABORTED;
1426 				splx(s);
1427 				/* enable interrupt from scsi */
1428 				sea_done(sea, scb);
1429 				return;
1430 			}
1431 			msgout = MSG_NOOP;
1432 			break;
1433 		case PH_CMD:
1434 			len = scb->xs->cmdlen;
1435 			data = (char *) scb->xs->cmd;
1436 			sea_transfer_pio(sea, &phase, &len, &data);
1437 			break;
1438 		case PH_STAT:
1439 			len = 1;
1440 			data = &tmp;
1441 			sea_transfer_pio(sea, &phase, &len, &data);
1442 			scb->xs->status = tmp;
1443 			break;
1444 		default:
1445 			printf("sea: unknown phase\n");
1446 		} /* switch (phase) */
1447 	} /* for (...) */
1448 
1449 	/* If we get here we have got a timeout! */
1450 	printf("%s: timeout in data transfer\n", sea->sc_dev.dv_xname);
1451 	scb->flags = SCB_TIMEOUT;
1452 	/* XXX Should I clear scsi-bus state? */
1453 	sea_done(sea, scb);
1454 }
1455