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mb89352.c revision 1.37
      1 /*	$NetBSD: mb89352.c,v 1.37 2004/09/25 12:17:30 tsutsui Exp $	*/
      2 /*	NecBSD: mb89352.c,v 1.4 1998/03/14 07:31:20 kmatsuda Exp	*/
      3 
      4 /*-
      5  * Copyright (c) 1996,97,98,99,2004 The NetBSD Foundation, Inc.
      6  * All rights reserved.
      7  *
      8  * This code is derived from software contributed to The NetBSD Foundation
      9  * by Charles M. Hannum, Masaru Oki and Kouichi Matsuda.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by Charles M. Hannum.
     22  * 4. The name of the author may not be used to endorse or promote products
     23  *    derived from this software without specific prior written permission.
     24  *
     25  * Copyright (c) 1994 Jarle Greipsland
     26  * All rights reserved.
     27  *
     28  * Redistribution and use in source and binary forms, with or without
     29  * modification, are permitted provided that the following conditions
     30  * are met:
     31  * 1. Redistributions of source code must retain the above copyright
     32  *    notice, this list of conditions and the following disclaimer.
     33  * 2. Redistributions in binary form must reproduce the above copyright
     34  *    notice, this list of conditions and the following disclaimer in the
     35  *    documentation and/or other materials provided with the distribution.
     36  * 3. The name of the author may not be used to endorse or promote products
     37  *    derived from this software without specific prior written permission.
     38  *
     39  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     40  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     41  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     42  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
     43  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     44  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     45  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     46  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     47  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
     48  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     49  * POSSIBILITY OF SUCH DAMAGE.
     50  */
     51 /*
     52  * [NetBSD for NEC PC-98 series]
     53  *  Copyright (c) 1996, 1997, 1998
     54  *	NetBSD/pc98 porting staff. All rights reserved.
     55  *  Copyright (c) 1996, 1997, 1998
     56  *	Kouichi Matsuda. All rights reserved.
     57  */
     58 
     59 /*
     60  * Acknowledgements: Many of the algorithms used in this driver are
     61  * inspired by the work of Julian Elischer (julian (at) tfs.com) and
     62  * Charles Hannum (mycroft (at) duality.gnu.ai.mit.edu).  Thanks a million!
     63  */
     64 
     65 /* TODO list:
     66  * 1) Get the DMA stuff working.
     67  * 2) Get the iov/uio stuff working. Is this a good thing ???
     68  * 3) Get the synch stuff working.
     69  * 4) Rewrite it to use malloc for the acb structs instead of static alloc.?
     70  */
     71 
     72 #include <sys/cdefs.h>
     73 __KERNEL_RCSID(0, "$NetBSD: mb89352.c,v 1.37 2004/09/25 12:17:30 tsutsui Exp $");
     74 
     75 #ifdef DDB
     76 #define	integrate
     77 #else
     78 #define	integrate	__inline static
     79 #endif
     80 
     81 /*
     82  * A few customizable items:
     83  */
     84 
     85 /* Synchronous data transfers? */
     86 #define SPC_USE_SYNCHRONOUS	0
     87 #define SPC_SYNC_REQ_ACK_OFS 	8
     88 
     89 /* Wide data transfers? */
     90 #define	SPC_USE_WIDE		0
     91 #define	SPC_MAX_WIDTH		0
     92 
     93 /* Max attempts made to transmit a message */
     94 #define SPC_MSG_MAX_ATTEMPT	3 /* Not used now XXX */
     95 
     96 /*
     97  * Some spin loop parameters (essentially how long to wait some places)
     98  * The problem(?) is that sometimes we expect either to be able to transmit a
     99  * byte or to get a new one from the SCSI bus pretty soon.  In order to avoid
    100  * returning from the interrupt just to get yanked back for the next byte we
    101  * may spin in the interrupt routine waiting for this byte to come.  How long?
    102  * This is really (SCSI) device and processor dependent.  Tuneable, I guess.
    103  */
    104 #define SPC_MSGIN_SPIN	1 	/* Will spinwait upto ?ms for a new msg byte */
    105 #define SPC_MSGOUT_SPIN	1
    106 
    107 /*
    108  * Include debug functions?  At the end of this file there are a bunch of
    109  * functions that will print out various information regarding queued SCSI
    110  * commands, driver state and chip contents.  You can call them from the
    111  * kernel debugger.  If you set SPC_DEBUG to 0 they are not included (the
    112  * kernel uses less memory) but you lose the debugging facilities.
    113  */
    114 #if 0
    115 #define SPC_DEBUG		1
    116 #endif
    117 
    118 #define	SPC_ABORT_TIMEOUT	2000	/* time to wait for abort */
    119 
    120 /* threshold length for DMA transfer */
    121 #define SPC_MIN_DMA_LEN	32
    122 
    123 #ifdef x68k	/* XXX it seems x68k SPC SCSI hardware has some quirks */
    124 #define NEED_DREQ_ON_HARDWARE_XFER
    125 #define NO_MANUAL_XFER
    126 #endif
    127 
    128 /* End of customizable parameters */
    129 
    130 /*
    131  * MB89352 SCSI Protocol Controller (SPC) routines.
    132  */
    133 
    134 #include "opt_ddb.h"
    135 
    136 #include <sys/param.h>
    137 #include <sys/systm.h>
    138 #include <sys/kernel.h>
    139 #include <sys/errno.h>
    140 #include <sys/ioctl.h>
    141 #include <sys/device.h>
    142 #include <sys/buf.h>
    143 #include <sys/proc.h>
    144 #include <sys/user.h>
    145 #include <sys/queue.h>
    146 
    147 #include <machine/intr.h>
    148 #include <machine/bus.h>
    149 
    150 #include <dev/scsipi/scsi_all.h>
    151 #include <dev/scsipi/scsipi_all.h>
    152 #include <dev/scsipi/scsi_message.h>
    153 #include <dev/scsipi/scsiconf.h>
    154 
    155 #include <dev/ic/mb89352reg.h>
    156 #include <dev/ic/mb89352var.h>
    157 
    158 #ifndef DDB
    159 #define	Debugger() panic("should call debugger here (mb89352.c)")
    160 #endif /* ! DDB */
    161 
    162 #if SPC_DEBUG
    163 int spc_debug = 0x00; /* SPC_SHOWSTART|SPC_SHOWMISC|SPC_SHOWTRACE; */
    164 #endif
    165 
    166 void	spc_done(struct spc_softc *, struct spc_acb *);
    167 void	spc_dequeue(struct spc_softc *, struct spc_acb *);
    168 void	spc_scsipi_request(struct scsipi_channel *, scsipi_adapter_req_t,
    169     void *);
    170 int	spc_poll(struct spc_softc *, struct scsipi_xfer *, int);
    171 integrate void	spc_sched_msgout(struct spc_softc *, u_char);
    172 integrate void	spc_setsync(struct spc_softc *, struct spc_tinfo *);
    173 void	spc_select(struct spc_softc *, struct spc_acb *);
    174 void	spc_timeout(void *);
    175 void	spc_scsi_reset(struct spc_softc *);
    176 void	spc_reset(struct spc_softc *);
    177 void	spc_free_acb(struct spc_softc *, struct spc_acb *, int);
    178 struct spc_acb* spc_get_acb(struct spc_softc *);
    179 int	spc_reselect(struct spc_softc *, int);
    180 void	spc_msgin(struct spc_softc *);
    181 void	spc_abort(struct spc_softc *, struct spc_acb *);
    182 void	spc_msgout(struct spc_softc *);
    183 int	spc_dataout_pio(struct spc_softc *, u_char *, int);
    184 int	spc_datain_pio(struct spc_softc *, u_char *, int);
    185 #if SPC_DEBUG
    186 void	spc_print_acb(struct spc_acb *);
    187 void	spc_dump_driver(struct spc_softc *);
    188 void	spc_dump89352(struct spc_softc *);
    189 void	spc_show_scsi_cmd(struct spc_acb *);
    190 void	spc_print_active_acb(void);
    191 #endif
    192 
    193 extern struct cfdriver spc_cd;
    194 
    195 /*
    196  * INITIALIZATION ROUTINES (probe, attach ++)
    197  */
    198 
    199 /*
    200  * Do the real search-for-device.
    201  * Prerequisite: sc->sc_iobase should be set to the proper value
    202  */
    203 int
    204 spc_find(bus_space_tag_t iot, bus_space_handle_t ioh, int bdid)
    205 {
    206 	long timeout = SPC_ABORT_TIMEOUT;
    207 
    208 	SPC_TRACE(("spc: probing for spc-chip\n"));
    209 	/*
    210 	 * Disable interrupts then reset the FUJITSU chip.
    211 	 */
    212 	bus_space_write_1(iot, ioh, SCTL, SCTL_DISABLE | SCTL_CTRLRST);
    213 	bus_space_write_1(iot, ioh, SCMD, 0);
    214 	bus_space_write_1(iot, ioh, PCTL, 0);
    215 	bus_space_write_1(iot, ioh, TEMP, 0);
    216 	bus_space_write_1(iot, ioh, TCH, 0);
    217 	bus_space_write_1(iot, ioh, TCM, 0);
    218 	bus_space_write_1(iot, ioh, TCL, 0);
    219 	bus_space_write_1(iot, ioh, INTS, 0);
    220 	bus_space_write_1(iot, ioh, SCTL,
    221 	    SCTL_DISABLE | SCTL_ABRT_ENAB | SCTL_PARITY_ENAB | SCTL_RESEL_ENAB);
    222 	bus_space_write_1(iot, ioh, BDID, bdid);
    223 	delay(400);
    224 	bus_space_write_1(iot, ioh, SCTL,
    225 	    bus_space_read_1(iot, ioh, SCTL) & ~SCTL_DISABLE);
    226 
    227 	/* The following detection is derived from spc.c
    228 	 * (by Takahide Matsutsuka) in FreeBSD/pccard-test.
    229 	 */
    230 	while (bus_space_read_1(iot, ioh, PSNS) && timeout) {
    231 		timeout--;
    232 		DELAY(1);
    233 	}
    234 	if (timeout == 0) {
    235 		printf("spc: find failed\n");
    236 		return 0;
    237 	}
    238 
    239 	SPC_START(("SPC found"));
    240 	return 1;
    241 }
    242 
    243 void
    244 spc_attach(struct spc_softc *sc)
    245 {
    246 	struct scsipi_adapter *adapt = &sc->sc_adapter;
    247 	struct scsipi_channel *chan = &sc->sc_channel;
    248 
    249 	SPC_TRACE(("spc_attach  "));
    250 	sc->sc_state = SPC_INIT;
    251 
    252 	sc->sc_freq = 20;	/* XXXX Assume 20 MHz. */
    253 
    254 #if SPC_USE_SYNCHRONOUS
    255 	/*
    256 	 * These are the bounds of the sync period, based on the frequency of
    257 	 * the chip's clock input and the size and offset of the sync period
    258 	 * register.
    259 	 *
    260 	 * For a 20MHz clock, this gives us 25, or 100nS, or 10MB/s, as a
    261 	 * maximum transfer rate, and 112.5, or 450nS, or 2.22MB/s, as a
    262 	 * minimum transfer rate.
    263 	 */
    264 	sc->sc_minsync = (2 * 250) / sc->sc_freq;
    265 	sc->sc_maxsync = (9 * 250) / sc->sc_freq;
    266 #endif
    267 
    268 	/*
    269 	 * Fill in the adapter.
    270 	 */
    271 	adapt->adapt_dev = &sc->sc_dev;
    272 	adapt->adapt_nchannels = 1;
    273 	adapt->adapt_openings = 7;
    274 	adapt->adapt_max_periph = 1;
    275 	adapt->adapt_request = spc_scsipi_request;
    276 	adapt->adapt_minphys = minphys;
    277 
    278 	chan->chan_adapter = &sc->sc_adapter;
    279 	chan->chan_bustype = &scsi_bustype;
    280 	chan->chan_channel = 0;
    281 	chan->chan_ntargets = 8;
    282 	chan->chan_nluns = 8;
    283 	chan->chan_id = sc->sc_initiator;
    284 
    285 	/*
    286 	 * Add reference to adapter so that we drop the reference after
    287 	 * config_found() to make sure the adatper is disabled.
    288 	 */
    289 	if (scsipi_adapter_addref(adapt) != 0) {
    290 		printf("%s: unable to enable controller\n",
    291 		    sc->sc_dev.dv_xname);
    292 		return;
    293 	}
    294 
    295 	spc_init(sc, 1);	/* Init chip and driver */
    296 
    297 	/*
    298 	 * ask the adapter what subunits are present
    299 	 */
    300 	sc->sc_child = config_found(&sc->sc_dev, chan, scsiprint);
    301 	scsipi_adapter_delref(adapt);
    302 }
    303 
    304 int
    305 spc_activate(struct device *self, enum devact act)
    306 {
    307 	struct spc_softc *sc = (void *)self;
    308 	int s, rv = 0;
    309 
    310 	s = splhigh();
    311 	switch (act) {
    312 	case DVACT_ACTIVATE:
    313 		rv = EOPNOTSUPP;
    314 		break;
    315 
    316 	case DVACT_DEACTIVATE:
    317 		if (sc->sc_child != NULL)
    318 			rv = config_deactivate(sc->sc_child);
    319 		break;
    320 	}
    321 	splx(s);
    322 
    323 	return (rv);
    324 }
    325 
    326 int
    327 spc_detach(struct device *self, int flags)
    328 {
    329 	struct spc_softc *sc = (void *)self;
    330 	int rv = 0;
    331 
    332 	if (sc->sc_child != NULL)
    333 		rv = config_detach(sc->sc_child, flags);
    334 
    335 	return (rv);
    336 }
    337 
    338 /*
    339  * Initialize MB89352 chip itself
    340  * The following conditions should hold:
    341  * spc_isa_probe should have succeeded, i.e. the iobase address in spc_softc
    342  * must be valid.
    343  */
    344 void
    345 spc_reset(struct spc_softc *sc)
    346 {
    347 	bus_space_tag_t iot = sc->sc_iot;
    348 	bus_space_handle_t ioh = sc->sc_ioh;
    349 
    350 	SPC_TRACE(("spc_reset  "));
    351 	/*
    352 	 * Disable interrupts then reset the FUJITSU chip.
    353 	 */
    354 	bus_space_write_1(iot, ioh, SCTL, SCTL_DISABLE | SCTL_CTRLRST);
    355 	bus_space_write_1(iot, ioh, SCMD, 0);
    356 	bus_space_write_1(iot, ioh, TMOD, 0);
    357 	bus_space_write_1(iot, ioh, PCTL, 0);
    358 	bus_space_write_1(iot, ioh, TEMP, 0);
    359 	bus_space_write_1(iot, ioh, TCH, 0);
    360 	bus_space_write_1(iot, ioh, TCM, 0);
    361 	bus_space_write_1(iot, ioh, TCL, 0);
    362 	bus_space_write_1(iot, ioh, INTS, 0);
    363 	bus_space_write_1(iot, ioh, SCTL,
    364 	    SCTL_DISABLE | SCTL_ABRT_ENAB | SCTL_PARITY_ENAB | SCTL_RESEL_ENAB);
    365 	bus_space_write_1(iot, ioh, BDID, sc->sc_initiator);
    366 	delay(400);
    367 	bus_space_write_1(iot, ioh, SCTL,
    368 	    bus_space_read_1(iot, ioh, SCTL) & ~SCTL_DISABLE);
    369 }
    370 
    371 
    372 /*
    373  * Pull the SCSI RST line for 500us.
    374  */
    375 void
    376 spc_scsi_reset(struct spc_softc *sc)
    377 {
    378 	bus_space_tag_t iot = sc->sc_iot;
    379 	bus_space_handle_t ioh = sc->sc_ioh;
    380 
    381 	SPC_TRACE(("spc_scsi_reset  "));
    382 	bus_space_write_1(iot, ioh, SCMD,
    383 	    bus_space_read_1(iot, ioh, SCMD) | SCMD_RST);
    384 	delay(500);
    385 	bus_space_write_1(iot, ioh, SCMD,
    386 	    bus_space_read_1(iot, ioh, SCMD) & ~SCMD_RST);
    387 	delay(50);
    388 }
    389 
    390 /*
    391  * Initialize spc SCSI driver.
    392  */
    393 void
    394 spc_init(struct spc_softc *sc, int bus_reset)
    395 {
    396 	struct spc_acb *acb;
    397 	int r;
    398 
    399 	SPC_TRACE(("spc_init  "));
    400 	if (bus_reset) {
    401 		spc_reset(sc);
    402 		spc_scsi_reset(sc);
    403 	}
    404 	spc_reset(sc);
    405 
    406 	if (sc->sc_state == SPC_INIT) {
    407 		/* First time through; initialize. */
    408 		TAILQ_INIT(&sc->ready_list);
    409 		TAILQ_INIT(&sc->nexus_list);
    410 		TAILQ_INIT(&sc->free_list);
    411 		sc->sc_nexus = NULL;
    412 		acb = sc->sc_acb;
    413 		memset(acb, 0, sizeof(sc->sc_acb));
    414 		for (r = 0; r < sizeof(sc->sc_acb) / sizeof(*acb); r++) {
    415 			TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);
    416 			acb++;
    417 		}
    418 		memset(&sc->sc_tinfo, 0, sizeof(sc->sc_tinfo));
    419 	} else {
    420 		/* Cancel any active commands. */
    421 		sc->sc_state = SPC_CLEANING;
    422 		if ((acb = sc->sc_nexus) != NULL) {
    423 			acb->xs->error = XS_DRIVER_STUFFUP;
    424 			callout_stop(&acb->xs->xs_callout);
    425 			spc_done(sc, acb);
    426 		}
    427 		while ((acb = TAILQ_FIRST(&sc->nexus_list)) != NULL) {
    428 			acb->xs->error = XS_DRIVER_STUFFUP;
    429 			callout_stop(&acb->xs->xs_callout);
    430 			spc_done(sc, acb);
    431 		}
    432 	}
    433 
    434 	sc->sc_prevphase = PH_INVALID;
    435 	for (r = 0; r < 8; r++) {
    436 		struct spc_tinfo *ti = &sc->sc_tinfo[r];
    437 
    438 		ti->flags = 0;
    439 #if SPC_USE_SYNCHRONOUS
    440 		ti->flags |= DO_SYNC;
    441 		ti->period = sc->sc_minsync;
    442 		ti->offset = SPC_SYNC_REQ_ACK_OFS;
    443 #else
    444 		ti->period = ti->offset = 0;
    445 #endif
    446 #if SPC_USE_WIDE
    447 		ti->flags |= DO_WIDE;
    448 		ti->width = SPC_MAX_WIDTH;
    449 #else
    450 		ti->width = 0;
    451 #endif
    452 	}
    453 
    454 	sc->sc_state = SPC_IDLE;
    455 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, SCTL,
    456 	    bus_space_read_1(sc->sc_iot, sc->sc_ioh, SCTL) | SCTL_INTR_ENAB);
    457 }
    458 
    459 void
    460 spc_free_acb(struct spc_softc *sc, struct spc_acb *acb, int flags)
    461 {
    462 	int s;
    463 
    464 	SPC_TRACE(("spc_free_acb  "));
    465 	s = splbio();
    466 
    467 	acb->flags = 0;
    468 	TAILQ_INSERT_HEAD(&sc->free_list, acb, chain);
    469 	splx(s);
    470 }
    471 
    472 struct spc_acb *
    473 spc_get_acb(struct spc_softc *sc)
    474 {
    475 	struct spc_acb *acb;
    476 	int s;
    477 
    478 	SPC_TRACE(("spc_get_acb  "));
    479 	s = splbio();
    480 	acb = TAILQ_FIRST(&sc->free_list);
    481 	if (acb != NULL) {
    482 		TAILQ_REMOVE(&sc->free_list, acb, chain);
    483 		acb->flags |= ACB_ALLOC;
    484 	}
    485 	splx(s);
    486 	return acb;
    487 }
    488 
    489 /*
    490  * DRIVER FUNCTIONS CALLABLE FROM HIGHER LEVEL DRIVERS
    491  */
    492 
    493 /*
    494  * Expected sequence:
    495  * 1) Command inserted into ready list
    496  * 2) Command selected for execution
    497  * 3) Command won arbitration and has selected target device
    498  * 4) Send message out (identify message, eventually also sync.negotiations)
    499  * 5) Send command
    500  * 5a) Receive disconnect message, disconnect.
    501  * 5b) Reselected by target
    502  * 5c) Receive identify message from target.
    503  * 6) Send or receive data
    504  * 7) Receive status
    505  * 8) Receive message (command complete etc.)
    506  */
    507 
    508 /*
    509  * Start a SCSI-command
    510  * This function is called by the higher level SCSI-driver to queue/run
    511  * SCSI-commands.
    512  */
    513 void
    514 spc_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
    515     void *arg)
    516 {
    517 	struct scsipi_xfer *xs;
    518 	struct scsipi_periph *periph;
    519 	struct spc_softc *sc = (void *)chan->chan_adapter->adapt_dev;
    520 	struct spc_acb *acb;
    521 	int s, flags;
    522 
    523 	switch (req) {
    524 	case ADAPTER_REQ_RUN_XFER:
    525 		xs = arg;
    526 		periph = xs->xs_periph;
    527 		SPC_TRACE(("spc_scsipi_request  "));
    528 		SPC_CMDS(("[0x%x, %d]->%d ", (int)xs->cmd->opcode, xs->cmdlen,
    529 		    periph->periph_target));
    530 
    531 		flags = xs->xs_control;
    532 		acb = spc_get_acb(sc);
    533 #ifdef DIAGNOSTIC
    534 		/*
    535 		 * This should nerver happen as we track the resources
    536 		 * in the mid-layer.
    537 		 */
    538 		if (acb == NULL) {
    539 			scsipi_printaddr(periph);
    540 			printf("unable to allocate acb\n");
    541 			panic("spc_scsipi_request");
    542 		}
    543 #endif
    544 
    545 		/* Initialize acb */
    546 		acb->xs = xs;
    547 		acb->timeout = xs->timeout;
    548 
    549 		if (xs->xs_control & XS_CTL_RESET) {
    550 			acb->flags |= ACB_RESET;
    551 			acb->scsipi_cmd_length = 0;
    552 			acb->data_length = 0;
    553 		} else {
    554 			memcpy(&acb->scsipi_cmd, xs->cmd, xs->cmdlen);
    555 			acb->scsipi_cmd_length = xs->cmdlen;
    556 			acb->data_addr = xs->data;
    557 			acb->data_length = xs->datalen;
    558 		}
    559 		acb->target_stat = 0;
    560 
    561 		s = splbio();
    562 
    563 		TAILQ_INSERT_TAIL(&sc->ready_list, acb, chain);
    564 		/*
    565 		 * Start scheduling unless a queue process is in progress.
    566 		 */
    567 		if (sc->sc_state == SPC_IDLE)
    568 			spc_sched(sc);
    569 		/*
    570 		 * After successful sending, check if we should return just now.
    571 		 * If so, return SUCCESSFULLY_QUEUED.
    572 		 */
    573 
    574 		splx(s);
    575 
    576 		if ((flags & XS_CTL_POLL) == 0)
    577 			return;
    578 
    579 		/* Not allowed to use interrupts, use polling instead */
    580 		s = splbio();
    581 		if (spc_poll(sc, xs, acb->timeout)) {
    582 			spc_timeout(acb);
    583 			if (spc_poll(sc, xs, acb->timeout))
    584 				spc_timeout(acb);
    585 		}
    586 		splx(s);
    587 		return;
    588 	case ADAPTER_REQ_GROW_RESOURCES:
    589 		/* XXX Not supported. */
    590 		return;
    591 	case ADAPTER_REQ_SET_XFER_MODE:
    592 	    {
    593 		/*
    594 		 * We don't support Sync, Wide, or Tagged Command Queuing.
    595 		 * Just callback now, to report this.
    596 		 */
    597 		struct scsipi_xfer_mode *xm = arg;
    598 
    599 		xm->xm_mode = 0;
    600 		xm->xm_period = 0;
    601 		xm->xm_offset = 0;
    602 		scsipi_async_event(chan, ASYNC_EVENT_XFER_MODE, xm);
    603 		return;
    604 	    }
    605 	}
    606 }
    607 
    608 /*
    609  * Used when interrupt driven I/O isn't allowed, e.g. during boot.
    610  */
    611 int
    612 spc_poll(struct spc_softc *sc, struct scsipi_xfer *xs, int count)
    613 {
    614 	bus_space_tag_t iot = sc->sc_iot;
    615 	bus_space_handle_t ioh = sc->sc_ioh;
    616 
    617 	SPC_TRACE(("spc_poll  "));
    618 	while (count) {
    619 		/*
    620 		 * If we had interrupts enabled, would we
    621 		 * have got an interrupt?
    622 		 */
    623 		if (bus_space_read_1(iot, ioh, INTS) != 0)
    624 			spc_intr(sc);
    625 		if ((xs->xs_status & XS_STS_DONE) != 0)
    626 			return 0;
    627 		delay(1000);
    628 		count--;
    629 	}
    630 	return 1;
    631 }
    632 
    633 /*
    634  * LOW LEVEL SCSI UTILITIES
    635  */
    636 
    637 integrate void
    638 spc_sched_msgout(struct spc_softc *sc, u_char m)
    639 {
    640 	bus_space_tag_t iot = sc->sc_iot;
    641 	bus_space_handle_t ioh = sc->sc_ioh;
    642 
    643 	SPC_TRACE(("spc_sched_msgout  "));
    644 	if (sc->sc_msgpriq == 0)
    645 		bus_space_write_1(iot, ioh, SCMD, SCMD_SET_ATN);
    646 	sc->sc_msgpriq |= m;
    647 }
    648 
    649 /*
    650  * Set synchronous transfer offset and period.
    651  */
    652 integrate void
    653 spc_setsync(struct spc_softc *sc, struct spc_tinfo *ti)
    654 {
    655 #if SPC_USE_SYNCHRONOUS
    656 	bus_space_tag_t iot = sc->sc_iot;
    657 	bus_space_handle_t ioh = sc->sc_ioh;
    658 
    659 	SPC_TRACE(("spc_setsync  "));
    660 	if (ti->offset != 0)
    661 		bus_space_write_1(iot, ioh, TMOD,
    662 		    ((ti->period * sc->sc_freq) / 250 - 2) << 4 | ti->offset);
    663 	else
    664 		bus_space_write_1(iot, ioh, TMOD, 0);
    665 #endif
    666 }
    667 
    668 /*
    669  * Start a selection.  This is used by spc_sched() to select an idle target.
    670  */
    671 void
    672 spc_select(struct spc_softc *sc, struct spc_acb *acb)
    673 {
    674 	struct scsipi_periph *periph = acb->xs->xs_periph;
    675 	int target = periph->periph_target;
    676 	struct spc_tinfo *ti = &sc->sc_tinfo[target];
    677 	bus_space_tag_t iot = sc->sc_iot;
    678 	bus_space_handle_t ioh = sc->sc_ioh;
    679 
    680 	SPC_TRACE(("spc_select  "));
    681 	spc_setsync(sc, ti);
    682 
    683 #if 0
    684 	bus_space_write_1(iot, ioh, SCMD, SCMD_SET_ATN);
    685 #endif
    686 
    687 	bus_space_write_1(iot, ioh, PCTL, 0);
    688 	bus_space_write_1(iot, ioh, TEMP,
    689 	    (1 << sc->sc_initiator) | (1 << target));
    690 	/*
    691 	 * Setup BSY timeout (selection timeout).
    692 	 * 250ms according to the SCSI specification.
    693 	 * T = (X * 256 + 15) * Tclf * 2  (Tclf = 200ns on x68k)
    694 	 * To setup 256ms timeout,
    695 	 * 128000ns/200ns = X * 256 + 15
    696 	 * 640 - 15 = X * 256
    697 	 * X = 625 / 256
    698 	 * X = 2 + 113 / 256
    699 	 *  ==> tch = 2, tcm = 113 (correct?)
    700 	 */
    701 	/* Time to the information transfer phase start. */
    702 	/* XXX These values should be calculated from sc_freq */
    703 	bus_space_write_1(iot, ioh, TCH, 2);
    704 	bus_space_write_1(iot, ioh, TCM, 113);
    705 	bus_space_write_1(iot, ioh, TCL, 3);
    706 	bus_space_write_1(iot, ioh, SCMD, SCMD_SELECT);
    707 
    708 	sc->sc_state = SPC_SELECTING;
    709 }
    710 
    711 int
    712 spc_reselect(struct spc_softc *sc, int message)
    713 {
    714 	u_char selid, target, lun;
    715 	struct spc_acb *acb;
    716 	struct scsipi_periph *periph;
    717 	struct spc_tinfo *ti;
    718 
    719 	SPC_TRACE(("spc_reselect  "));
    720 	/*
    721 	 * The SCSI chip made a snapshot of the data bus while the reselection
    722 	 * was being negotiated.  This enables us to determine which target did
    723 	 * the reselect.
    724 	 */
    725 	selid = sc->sc_selid & ~(1 << sc->sc_initiator);
    726 	if (selid & (selid - 1)) {
    727 		printf("%s: reselect with invalid selid %02x; "
    728 		    "sending DEVICE RESET\n", sc->sc_dev.dv_xname, selid);
    729 		SPC_BREAK();
    730 		goto reset;
    731 	}
    732 
    733 	/*
    734 	 * Search wait queue for disconnected cmd
    735 	 * The list should be short, so I haven't bothered with
    736 	 * any more sophisticated structures than a simple
    737 	 * singly linked list.
    738 	 */
    739 	target = ffs(selid) - 1;
    740 	lun = message & 0x07;
    741 	TAILQ_FOREACH(acb, &sc->nexus_list, chain) {
    742 		periph = acb->xs->xs_periph;
    743 		if (periph->periph_target == target &&
    744 		    periph->periph_lun == lun)
    745 			break;
    746 	}
    747 	if (acb == NULL) {
    748 		printf("%s: reselect from target %d lun %d with no nexus; "
    749 		    "sending ABORT\n", sc->sc_dev.dv_xname, target, lun);
    750 		SPC_BREAK();
    751 		goto abort;
    752 	}
    753 
    754 	/* Make this nexus active again. */
    755 	TAILQ_REMOVE(&sc->nexus_list, acb, chain);
    756 	sc->sc_state = SPC_CONNECTED;
    757 	sc->sc_nexus = acb;
    758 	ti = &sc->sc_tinfo[target];
    759 	ti->lubusy |= (1 << lun);
    760 	spc_setsync(sc, ti);
    761 
    762 	if (acb->flags & ACB_RESET)
    763 		spc_sched_msgout(sc, SEND_DEV_RESET);
    764 	else if (acb->flags & ACB_ABORT)
    765 		spc_sched_msgout(sc, SEND_ABORT);
    766 
    767 	/* Do an implicit RESTORE POINTERS. */
    768 	sc->sc_dp = acb->data_addr;
    769 	sc->sc_dleft = acb->data_length;
    770 	sc->sc_cp = (u_char *)&acb->scsipi_cmd;
    771 	sc->sc_cleft = acb->scsipi_cmd_length;
    772 
    773 	return (0);
    774 
    775 reset:
    776 	spc_sched_msgout(sc, SEND_DEV_RESET);
    777 	return (1);
    778 
    779 abort:
    780 	spc_sched_msgout(sc, SEND_ABORT);
    781 	return (1);
    782 }
    783 
    784 /*
    785  * Schedule a SCSI operation.  This has now been pulled out of the interrupt
    786  * handler so that we may call it from spc_scsi_cmd and spc_done.  This may
    787  * save us an unnecessary interrupt just to get things going.  Should only be
    788  * called when state == SPC_IDLE and at bio pl.
    789  */
    790 void
    791 spc_sched(struct spc_softc *sc)
    792 {
    793 	struct spc_acb *acb;
    794 	struct scsipi_periph *periph;
    795 	struct spc_tinfo *ti;
    796 
    797 	/* missing the hw, just return and wait for our hw */
    798 	if (sc->sc_flags & SPC_INACTIVE)
    799 		return;
    800 	SPC_TRACE(("spc_sched  "));
    801 	/*
    802 	 * Find first acb in ready queue that is for a target/lunit pair that
    803 	 * is not busy.
    804 	 */
    805 	TAILQ_FOREACH(acb, &sc->ready_list, chain) {
    806 		periph = acb->xs->xs_periph;
    807 		ti = &sc->sc_tinfo[periph->periph_target];
    808 		if ((ti->lubusy & (1 << periph->periph_lun)) == 0) {
    809 			SPC_MISC(("selecting %d:%d  ",
    810 			    periph->periph_target, periph->periph_lun));
    811 			TAILQ_REMOVE(&sc->ready_list, acb, chain);
    812 			sc->sc_nexus = acb;
    813 			spc_select(sc, acb);
    814 			return;
    815 		} else
    816 			SPC_MISC(("%d:%d busy\n",
    817 			    periph->periph_target, periph->periph_lun));
    818 	}
    819 	SPC_MISC(("idle  "));
    820 	/* Nothing to start; just enable reselections and wait. */
    821 }
    822 
    823 /*
    824  * POST PROCESSING OF SCSI_CMD (usually current)
    825  */
    826 void
    827 spc_done(struct spc_softc *sc, struct spc_acb *acb)
    828 {
    829 	struct scsipi_xfer *xs = acb->xs;
    830 	struct scsipi_periph *periph = xs->xs_periph;
    831 	struct spc_tinfo *ti = &sc->sc_tinfo[periph->periph_target];
    832 
    833 	SPC_TRACE(("spc_done  "));
    834 
    835 	if (xs->error == XS_NOERROR) {
    836 		if (acb->flags & ACB_ABORT) {
    837 			xs->error = XS_DRIVER_STUFFUP;
    838 		} else {
    839 			switch (acb->target_stat) {
    840 			case SCSI_CHECK:
    841 				/* First, save the return values */
    842 				xs->resid = acb->data_length;
    843 				/* FALLTHROUGH */
    844 			case SCSI_BUSY:
    845 				xs->status = acb->target_stat;
    846 				xs->error = XS_BUSY;
    847 				break;
    848 			case SCSI_OK:
    849 				xs->resid = acb->data_length;
    850 				break;
    851 			default:
    852 				xs->error = XS_DRIVER_STUFFUP;
    853 #if SPC_DEBUG
    854 				printf("%s: spc_done: bad stat 0x%x\n",
    855 				    sc->sc_dev.dv_xname, acb->target_stat);
    856 #endif
    857 				break;
    858 			}
    859 		}
    860 	}
    861 
    862 #if SPC_DEBUG
    863 	if ((spc_debug & SPC_SHOWMISC) != 0) {
    864 		if (xs->resid != 0)
    865 			printf("resid=%d ", xs->resid);
    866 		else
    867 			printf("error=%d\n", xs->error);
    868 	}
    869 #endif
    870 
    871 	/*
    872 	 * Remove the ACB from whatever queue it happens to be on.
    873 	 */
    874 	if (acb->flags & ACB_NEXUS)
    875 		ti->lubusy &= ~(1 << periph->periph_lun);
    876 	if (acb == sc->sc_nexus) {
    877 		sc->sc_nexus = NULL;
    878 		sc->sc_state = SPC_IDLE;
    879 		spc_sched(sc);
    880 	} else
    881 		spc_dequeue(sc, acb);
    882 
    883 	spc_free_acb(sc, acb, xs->xs_control);
    884 	ti->cmds++;
    885 	scsipi_done(xs);
    886 }
    887 
    888 void
    889 spc_dequeue(struct spc_softc *sc, struct spc_acb *acb)
    890 {
    891 
    892 	SPC_TRACE(("spc_dequeue  "));
    893 	if (acb->flags & ACB_NEXUS)
    894 		TAILQ_REMOVE(&sc->nexus_list, acb, chain);
    895 	else
    896 		TAILQ_REMOVE(&sc->ready_list, acb, chain);
    897 }
    898 
    899 /*
    900  * INTERRUPT/PROTOCOL ENGINE
    901  */
    902 
    903 /*
    904  * Precondition:
    905  * The SCSI bus is already in the MSGI phase and there is a message byte
    906  * on the bus, along with an asserted REQ signal.
    907  */
    908 void
    909 spc_msgin(struct spc_softc *sc)
    910 {
    911 	bus_space_tag_t iot = sc->sc_iot;
    912 	bus_space_handle_t ioh = sc->sc_ioh;
    913 	int n;
    914 	u_int8_t msg;
    915 
    916 	SPC_TRACE(("spc_msgin  "));
    917 
    918 	if (sc->sc_prevphase == PH_MSGIN) {
    919 		/* This is a continuation of the previous message. */
    920 		n = sc->sc_imp - sc->sc_imess;
    921 		goto nextbyte;
    922 	}
    923 
    924 	/* This is a new MESSAGE IN phase.  Clean up our state. */
    925 	sc->sc_flags &= ~SPC_DROP_MSGIN;
    926 
    927 nextmsg:
    928 	n = 0;
    929 	sc->sc_imp = &sc->sc_imess[n];
    930 
    931 nextbyte:
    932 	/*
    933 	 * Read a whole message, but don't ack the last byte.  If we reject the
    934 	 * message, we have to assert ATN during the message transfer phase
    935 	 * itself.
    936 	 */
    937 	for (;;) {
    938 #ifdef NO_MANUAL_XFER /* XXX */
    939 		if (bus_space_read_1(iot, ioh, INTS) != 0) {
    940 			/*
    941 			 * Target left MESSAGE IN, probably because it
    942 			 * a) noticed our ATN signal, or
    943 			 * b) ran out of messages.
    944 			 */
    945 			goto out;
    946 		}
    947 #endif
    948 		/* If parity error, just dump everything on the floor. */
    949 		if ((bus_space_read_1(iot, ioh, SERR) &
    950 		     (SERR_SCSI_PAR|SERR_SPC_PAR)) != 0) {
    951 			sc->sc_flags |= SPC_DROP_MSGIN;
    952 			spc_sched_msgout(sc, SEND_PARITY_ERROR);
    953 		}
    954 
    955 #ifdef NO_MANUAL_XFER /* XXX */
    956 		/* send TRANSFER command. */
    957 		bus_space_write_1(iot, ioh, TCH, 0);
    958 		bus_space_write_1(iot, ioh, TCM, 0);
    959 		bus_space_write_1(iot, ioh, TCL, 1);
    960 		bus_space_write_1(iot, ioh, PCTL,
    961 		    sc->sc_phase | PCTL_BFINT_ENAB);
    962 #ifdef NEED_DREQ_ON_HARDWARE_XFER
    963 		bus_space_write_1(iot, ioh, SCMD, SCMD_XFR);
    964 #else
    965 		bus_space_write_1(iot, ioh, SCMD, SCMD_XFR | SCMD_PROG_XFR);
    966 #endif
    967 		for (;;) {
    968 			if ((bus_space_read_1(iot, ioh, SSTS) &
    969 			    SSTS_DREG_EMPTY) == 0)
    970 				break;
    971 			if (bus_space_read_1(iot, ioh, INTS) != 0)
    972 				goto out;
    973 		}
    974 		msg = bus_space_read_1(iot, ioh, DREG);
    975 #else
    976 		if ((bus_space_read_1(iot, ioh, PSNS) & PSNS_ATN) != 0)
    977 			bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ATN);
    978 		bus_space_write_1(iot, ioh, PCTL, PCTL_BFINT_ENAB | PH_MSGIN);
    979 
    980 		while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) == 0) {
    981 			if ((bus_space_read_1(iot, ioh, PSNS) & PH_MASK)
    982 			    != PH_MSGIN ||
    983 			    bus_space_read_1(iot, ioh, INTS) != 0)
    984 				/*
    985 				 * Target left MESSAGE IN, probably because it
    986 				 * a) noticed our ATN signal, or
    987 				 * b) ran out of messages.
    988 				 */
    989 				goto out;
    990 			DELAY(1);	/* XXX needs timeout */
    991 		}
    992 
    993 		msg = bus_space_read_1(iot, ioh, TEMP);
    994 #endif
    995 
    996 		/* Gather incoming message bytes if needed. */
    997 		if ((sc->sc_flags & SPC_DROP_MSGIN) == 0) {
    998 			if (n >= SPC_MAX_MSG_LEN) {
    999 				sc->sc_flags |= SPC_DROP_MSGIN;
   1000 				spc_sched_msgout(sc, SEND_REJECT);
   1001 			} else {
   1002 				*sc->sc_imp++ = msg;
   1003 				n++;
   1004 				/*
   1005 				 * This testing is suboptimal, but most
   1006 				 * messages will be of the one byte variety, so
   1007 				 * it should not affect performance
   1008 				 * significantly.
   1009 				 */
   1010 				if (n == 1 && MSG_IS1BYTE(sc->sc_imess[0]))
   1011 					break;
   1012 				if (n == 2 && MSG_IS2BYTE(sc->sc_imess[0]))
   1013 					break;
   1014 				if (n >= 3 && MSG_ISEXTENDED(sc->sc_imess[0]) &&
   1015 				    n == sc->sc_imess[1] + 2)
   1016 					break;
   1017 			}
   1018 		}
   1019 		/*
   1020 		 * If we reach this spot we're either:
   1021 		 * a) in the middle of a multi-byte message, or
   1022 		 * b) dropping bytes.
   1023 		 */
   1024 
   1025 #ifndef NO_MANUAL_XFER /* XXX */
   1026 		/* Ack the last byte read. */
   1027 		bus_space_write_1(iot, ioh, SCMD, SCMD_SET_ACK);
   1028 		while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) != 0)
   1029 			DELAY(1);	/* XXX needs timeout */
   1030 		bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ACK);
   1031 #endif
   1032 	}
   1033 
   1034 	SPC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));
   1035 
   1036 	/* We now have a complete message.  Parse it. */
   1037 	switch (sc->sc_state) {
   1038 		struct spc_acb *acb;
   1039 		struct scsipi_periph *periph;
   1040 		struct spc_tinfo *ti;
   1041 
   1042 	case SPC_CONNECTED:
   1043 		SPC_ASSERT(sc->sc_nexus != NULL);
   1044 		acb = sc->sc_nexus;
   1045 		ti = &sc->sc_tinfo[acb->xs->xs_periph->periph_target];
   1046 
   1047 		switch (sc->sc_imess[0]) {
   1048 		case MSG_CMDCOMPLETE:
   1049 			if (sc->sc_dleft < 0) {
   1050 				periph = acb->xs->xs_periph;
   1051 				printf("%s: %ld extra bytes from %d:%d\n",
   1052 				    sc->sc_dev.dv_xname, (long)-sc->sc_dleft,
   1053 				    periph->periph_target, periph->periph_lun);
   1054 				sc->sc_dleft = 0;
   1055 			}
   1056 			acb->xs->resid = acb->data_length = sc->sc_dleft;
   1057 			sc->sc_state = SPC_CMDCOMPLETE;
   1058 			break;
   1059 
   1060 		case MSG_PARITY_ERROR:
   1061 			/* Resend the last message. */
   1062 			spc_sched_msgout(sc, sc->sc_lastmsg);
   1063 			break;
   1064 
   1065 		case MSG_MESSAGE_REJECT:
   1066 			SPC_MISC(("message rejected %02x  ", sc->sc_lastmsg));
   1067 			switch (sc->sc_lastmsg) {
   1068 #if SPC_USE_SYNCHRONOUS + SPC_USE_WIDE
   1069 			case SEND_IDENTIFY:
   1070 				ti->flags &= ~(DO_SYNC | DO_WIDE);
   1071 				ti->period = ti->offset = 0;
   1072 				spc_setsync(sc, ti);
   1073 				ti->width = 0;
   1074 				break;
   1075 #endif
   1076 #if SPC_USE_SYNCHRONOUS
   1077 			case SEND_SDTR:
   1078 				ti->flags &= ~DO_SYNC;
   1079 				ti->period = ti->offset = 0;
   1080 				spc_setsync(sc, ti);
   1081 				break;
   1082 #endif
   1083 #if SPC_USE_WIDE
   1084 			case SEND_WDTR:
   1085 				ti->flags &= ~DO_WIDE;
   1086 				ti->width = 0;
   1087 				break;
   1088 #endif
   1089 			case SEND_INIT_DET_ERR:
   1090 				spc_sched_msgout(sc, SEND_ABORT);
   1091 				break;
   1092 			}
   1093 			break;
   1094 
   1095 		case MSG_NOOP:
   1096 			break;
   1097 
   1098 		case MSG_DISCONNECT:
   1099 			ti->dconns++;
   1100 			sc->sc_state = SPC_DISCONNECT;
   1101 			break;
   1102 
   1103 		case MSG_SAVEDATAPOINTER:
   1104 			acb->data_addr = sc->sc_dp;
   1105 			acb->data_length = sc->sc_dleft;
   1106 			break;
   1107 
   1108 		case MSG_RESTOREPOINTERS:
   1109 			sc->sc_dp = acb->data_addr;
   1110 			sc->sc_dleft = acb->data_length;
   1111 			sc->sc_cp = (u_char *)&acb->scsipi_cmd;
   1112 			sc->sc_cleft = acb->scsipi_cmd_length;
   1113 			break;
   1114 
   1115 		case MSG_EXTENDED:
   1116 			switch (sc->sc_imess[2]) {
   1117 #if SPC_USE_SYNCHRONOUS
   1118 			case MSG_EXT_SDTR:
   1119 				if (sc->sc_imess[1] != 3)
   1120 					goto reject;
   1121 				ti->period = sc->sc_imess[3];
   1122 				ti->offset = sc->sc_imess[4];
   1123 				ti->flags &= ~DO_SYNC;
   1124 				if (ti->offset == 0) {
   1125 				} else if (ti->period < sc->sc_minsync ||
   1126 				    ti->period > sc->sc_maxsync ||
   1127 				    ti->offset > 8) {
   1128 					ti->period = ti->offset = 0;
   1129 					spc_sched_msgout(sc, SEND_SDTR);
   1130 				} else {
   1131 					scsipi_printaddr(acb->xs->xs_periph);
   1132 					printf("sync, offset %d, "
   1133 					    "period %dnsec\n",
   1134 					    ti->offset, ti->period * 4);
   1135 				}
   1136 				spc_setsync(sc, ti);
   1137 				break;
   1138 #endif
   1139 
   1140 #if SPC_USE_WIDE
   1141 			case MSG_EXT_WDTR:
   1142 				if (sc->sc_imess[1] != 2)
   1143 					goto reject;
   1144 				ti->width = sc->sc_imess[3];
   1145 				ti->flags &= ~DO_WIDE;
   1146 				if (ti->width == 0) {
   1147 				} else if (ti->width > SPC_MAX_WIDTH) {
   1148 					ti->width = 0;
   1149 					spc_sched_msgout(sc, SEND_WDTR);
   1150 				} else {
   1151 					scsipi_printaddr(acb->xs->xs_periph);
   1152 					printf("wide, width %d\n",
   1153 					    1 << (3 + ti->width));
   1154 				}
   1155 				break;
   1156 #endif
   1157 
   1158 			default:
   1159 				printf("%s: unrecognized MESSAGE EXTENDED; "
   1160 				    "sending REJECT\n", sc->sc_dev.dv_xname);
   1161 				SPC_BREAK();
   1162 				goto reject;
   1163 			}
   1164 			break;
   1165 
   1166 		default:
   1167 			printf("%s: unrecognized MESSAGE; sending REJECT\n",
   1168 			    sc->sc_dev.dv_xname);
   1169 			SPC_BREAK();
   1170 		reject:
   1171 			spc_sched_msgout(sc, SEND_REJECT);
   1172 			break;
   1173 		}
   1174 		break;
   1175 
   1176 	case SPC_RESELECTED:
   1177 		if (!MSG_ISIDENTIFY(sc->sc_imess[0])) {
   1178 			printf("%s: reselect without IDENTIFY; "
   1179 			    "sending DEVICE RESET\n", sc->sc_dev.dv_xname);
   1180 			SPC_BREAK();
   1181 			goto reset;
   1182 		}
   1183 
   1184 		(void) spc_reselect(sc, sc->sc_imess[0]);
   1185 		break;
   1186 
   1187 	default:
   1188 		printf("%s: unexpected MESSAGE IN; sending DEVICE RESET\n",
   1189 		    sc->sc_dev.dv_xname);
   1190 		SPC_BREAK();
   1191 	reset:
   1192 		spc_sched_msgout(sc, SEND_DEV_RESET);
   1193 		break;
   1194 
   1195 #ifdef notdef
   1196 	abort:
   1197 		spc_sched_msgout(sc, SEND_ABORT);
   1198 		break;
   1199 #endif
   1200 	}
   1201 
   1202 #ifndef NO_MANUAL_XFER /* XXX */
   1203 	/* Ack the last message byte. */
   1204 	bus_space_write_1(iot, ioh, SCMD, SCMD_SET_ACK);
   1205 	while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) != 0)
   1206 		DELAY(1);	/* XXX needs timeout */
   1207 	bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ACK);
   1208 #endif
   1209 
   1210 	/* Go get the next message, if any. */
   1211 	goto nextmsg;
   1212 
   1213 out:
   1214 #ifdef NO_MANUAL_XFER /* XXX */
   1215 	/* Ack the last message byte. */
   1216 	bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ACK);
   1217 #endif
   1218 	SPC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));
   1219 }
   1220 
   1221 /*
   1222  * Send the highest priority, scheduled message.
   1223  */
   1224 void
   1225 spc_msgout(struct spc_softc *sc)
   1226 {
   1227 	bus_space_tag_t iot = sc->sc_iot;
   1228 	bus_space_handle_t ioh = sc->sc_ioh;
   1229 #if SPC_USE_SYNCHRONOUS
   1230 	struct spc_tinfo *ti;
   1231 #endif
   1232 	int n;
   1233 
   1234 	SPC_TRACE(("spc_msgout  "));
   1235 
   1236 	if (sc->sc_prevphase == PH_MSGOUT) {
   1237 		if (sc->sc_omp == sc->sc_omess) {
   1238 			/*
   1239 			 * This is a retransmission.
   1240 			 *
   1241 			 * We get here if the target stayed in MESSAGE OUT
   1242 			 * phase.  Section 5.1.9.2 of the SCSI 2 spec indicates
   1243 			 * that all of the previously transmitted messages must
   1244 			 * be sent again, in the same order.  Therefore, we
   1245 			 * requeue all the previously transmitted messages, and
   1246 			 * start again from the top.  Our simple priority
   1247 			 * scheme keeps the messages in the right order.
   1248 			 */
   1249 			SPC_MISC(("retransmitting  "));
   1250 			sc->sc_msgpriq |= sc->sc_msgoutq;
   1251 			/*
   1252 			 * Set ATN.  If we're just sending a trivial 1-byte
   1253 			 * message, we'll clear ATN later on anyway.
   1254 			 */
   1255 			bus_space_write_1(iot, ioh, SCMD,
   1256 			    SCMD_SET_ATN);	/* XXX? */
   1257 		} else {
   1258 			/* This is a continuation of the previous message. */
   1259 			n = sc->sc_omp - sc->sc_omess;
   1260 			goto nextbyte;
   1261 		}
   1262 	}
   1263 
   1264 	/* No messages transmitted so far. */
   1265 	sc->sc_msgoutq = 0;
   1266 	sc->sc_lastmsg = 0;
   1267 
   1268 nextmsg:
   1269 	/* Pick up highest priority message. */
   1270 	sc->sc_currmsg = sc->sc_msgpriq & -sc->sc_msgpriq;
   1271 	sc->sc_msgpriq &= ~sc->sc_currmsg;
   1272 	sc->sc_msgoutq |= sc->sc_currmsg;
   1273 
   1274 	/* Build the outgoing message data. */
   1275 	switch (sc->sc_currmsg) {
   1276 	case SEND_IDENTIFY:
   1277 		SPC_ASSERT(sc->sc_nexus != NULL);
   1278 		sc->sc_omess[0] =
   1279 		    MSG_IDENTIFY(sc->sc_nexus->xs->xs_periph->periph_lun, 1);
   1280 		n = 1;
   1281 		break;
   1282 
   1283 #if SPC_USE_SYNCHRONOUS
   1284 	case SEND_SDTR:
   1285 		SPC_ASSERT(sc->sc_nexus != NULL);
   1286 		ti = &sc->sc_tinfo[sc->sc_nexus->xs->xs_periph->periph_target];
   1287 		sc->sc_omess[4] = MSG_EXTENDED;
   1288 		sc->sc_omess[3] = MSG_EXT_SDTR_LEN;
   1289 		sc->sc_omess[2] = MSG_EXT_SDTR;
   1290 		sc->sc_omess[1] = ti->period >> 2;
   1291 		sc->sc_omess[0] = ti->offset;
   1292 		n = 5;
   1293 		break;
   1294 #endif
   1295 
   1296 #if SPC_USE_WIDE
   1297 	case SEND_WDTR:
   1298 		SPC_ASSERT(sc->sc_nexus != NULL);
   1299 		ti = &sc->sc_tinfo[sc->sc_nexus->xs->xs_periph->periph_target];
   1300 		sc->sc_omess[3] = MSG_EXTENDED;
   1301 		sc->sc_omess[2] = MSG_EXT_WDTR_LEN;
   1302 		sc->sc_omess[1] = MSG_EXT_WDTR;
   1303 		sc->sc_omess[0] = ti->width;
   1304 		n = 4;
   1305 		break;
   1306 #endif
   1307 
   1308 	case SEND_DEV_RESET:
   1309 		sc->sc_flags |= SPC_ABORTING;
   1310 		sc->sc_omess[0] = MSG_BUS_DEV_RESET;
   1311 		n = 1;
   1312 		break;
   1313 
   1314 	case SEND_REJECT:
   1315 		sc->sc_omess[0] = MSG_MESSAGE_REJECT;
   1316 		n = 1;
   1317 		break;
   1318 
   1319 	case SEND_PARITY_ERROR:
   1320 		sc->sc_omess[0] = MSG_PARITY_ERROR;
   1321 		n = 1;
   1322 		break;
   1323 
   1324 	case SEND_INIT_DET_ERR:
   1325 		sc->sc_omess[0] = MSG_INITIATOR_DET_ERR;
   1326 		n = 1;
   1327 		break;
   1328 
   1329 	case SEND_ABORT:
   1330 		sc->sc_flags |= SPC_ABORTING;
   1331 		sc->sc_omess[0] = MSG_ABORT;
   1332 		n = 1;
   1333 		break;
   1334 
   1335 	default:
   1336 		printf("%s: unexpected MESSAGE OUT; sending NOOP\n",
   1337 		    sc->sc_dev.dv_xname);
   1338 		SPC_BREAK();
   1339 		sc->sc_omess[0] = MSG_NOOP;
   1340 		n = 1;
   1341 		break;
   1342 	}
   1343 	sc->sc_omp = &sc->sc_omess[n];
   1344 
   1345 nextbyte:
   1346 	/* Send message bytes. */
   1347 	/* send TRANSFER command. */
   1348 	bus_space_write_1(iot, ioh, TCH, n >> 16);
   1349 	bus_space_write_1(iot, ioh, TCM, n >> 8);
   1350 	bus_space_write_1(iot, ioh, TCL, n);
   1351 	bus_space_write_1(iot, ioh, PCTL, sc->sc_phase | PCTL_BFINT_ENAB);
   1352 #ifdef NEED_DREQ_ON_HARDWARE_XFER
   1353 	bus_space_write_1(iot, ioh, SCMD, SCMD_XFR);	/* XXX */
   1354 #else
   1355 	bus_space_write_1(iot, ioh, SCMD,
   1356 	    SCMD_XFR | SCMD_PROG_XFR);
   1357 #endif
   1358 	for (;;) {
   1359 		if ((bus_space_read_1(iot, ioh, SSTS) & SSTS_BUSY) != 0)
   1360 			break;
   1361 		if (bus_space_read_1(iot, ioh, INTS) != 0)
   1362 			goto out;
   1363 	}
   1364 	for (;;) {
   1365 #if 0
   1366 		for (;;) {
   1367 			if ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) != 0)
   1368 				break;
   1369 			/* Wait for REQINIT.  XXX Need timeout. */
   1370 		}
   1371 #endif
   1372 		if (bus_space_read_1(iot, ioh, INTS) != 0) {
   1373 			/*
   1374 			 * Target left MESSAGE OUT, possibly to reject
   1375 			 * our message.
   1376 			 *
   1377 			 * If this is the last message being sent, then we
   1378 			 * deassert ATN, since either the target is going to
   1379 			 * ignore this message, or it's going to ask for a
   1380 			 * retransmission via MESSAGE PARITY ERROR (in which
   1381 			 * case we reassert ATN anyway).
   1382 			 */
   1383 #if 0
   1384 			if (sc->sc_msgpriq == 0)
   1385 				bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ATN);
   1386 #endif
   1387 			goto out;
   1388 		}
   1389 
   1390 #if 0
   1391 		/* Clear ATN before last byte if this is the last message. */
   1392 		if (n == 1 && sc->sc_msgpriq == 0)
   1393 			bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ATN);
   1394 #endif
   1395 
   1396 		while ((bus_space_read_1(iot, ioh, SSTS) & SSTS_DREG_FULL) != 0)
   1397 			DELAY(1);
   1398 		/* Send message byte. */
   1399 		bus_space_write_1(iot, ioh, DREG, *--sc->sc_omp);
   1400 		--n;
   1401 		/* Keep track of the last message we've sent any bytes of. */
   1402 		sc->sc_lastmsg = sc->sc_currmsg;
   1403 #if 0
   1404 		/* Wait for ACK to be negated.  XXX Need timeout. */
   1405 		while ((bus_space_read_1(iot, ioh, PSNS) & ACKI) != 0)
   1406 			;
   1407 #endif
   1408 
   1409 		if (n == 0)
   1410 			break;
   1411 	}
   1412 
   1413 	/* We get here only if the entire message has been transmitted. */
   1414 	if (sc->sc_msgpriq != 0) {
   1415 		/* There are more outgoing messages. */
   1416 		goto nextmsg;
   1417 	}
   1418 
   1419 	/*
   1420 	 * The last message has been transmitted.  We need to remember the last
   1421 	 * message transmitted (in case the target switches to MESSAGE IN phase
   1422 	 * and sends a MESSAGE REJECT), and the list of messages transmitted
   1423 	 * this time around (in case the target stays in MESSAGE OUT phase to
   1424 	 * request a retransmit).
   1425 	 */
   1426 
   1427 out:
   1428 	/* Disable REQ/ACK protocol. */
   1429 	return;
   1430 }
   1431 
   1432 /*
   1433  * spc_dataout_pio: perform a data transfer using the FIFO datapath in the spc
   1434  * Precondition: The SCSI bus should be in the DOUT phase, with REQ asserted
   1435  * and ACK deasserted (i.e. waiting for a data byte)
   1436  *
   1437  * This new revision has been optimized (I tried) to make the common case fast,
   1438  * and the rarer cases (as a result) somewhat more comlex
   1439  */
   1440 int
   1441 spc_dataout_pio(struct spc_softc *sc, u_char *p, int n)
   1442 {
   1443 	bus_space_tag_t iot = sc->sc_iot;
   1444 	bus_space_handle_t ioh = sc->sc_ioh;
   1445 	u_char intstat = 0;
   1446 	int out = 0;
   1447 #define DOUTAMOUNT 8		/* Full FIFO */
   1448 
   1449 	SPC_TRACE(("spc_dataout_pio  "));
   1450 	/* send TRANSFER command. */
   1451 	bus_space_write_1(iot, ioh, TCH, n >> 16);
   1452 	bus_space_write_1(iot, ioh, TCM, n >> 8);
   1453 	bus_space_write_1(iot, ioh, TCL, n);
   1454 	bus_space_write_1(iot, ioh, PCTL, sc->sc_phase | PCTL_BFINT_ENAB);
   1455 #ifdef NEED_DREQ_ON_HARDWARE_XFER
   1456 	bus_space_write_1(iot, ioh, SCMD, SCMD_XFR);	/* XXX */
   1457 #else
   1458 	bus_space_write_1(iot, ioh, SCMD,
   1459 	    SCMD_XFR | SCMD_PROG_XFR);	/* XXX */
   1460 #endif
   1461 	for (;;) {
   1462 		if ((bus_space_read_1(iot, ioh, SSTS) & SSTS_BUSY) != 0)
   1463 			break;
   1464 		if (bus_space_read_1(iot, ioh, INTS) != 0)
   1465 			break;
   1466 	}
   1467 
   1468 	/*
   1469 	 * I have tried to make the main loop as tight as possible.  This
   1470 	 * means that some of the code following the loop is a bit more
   1471 	 * complex than otherwise.
   1472 	 */
   1473 	while (n > 0) {
   1474 		int xfer;
   1475 
   1476 		for (;;) {
   1477 			intstat = bus_space_read_1(iot, ioh, INTS);
   1478 			/* Wait till buffer is empty. */
   1479 			if ((bus_space_read_1(iot, ioh, SSTS) &
   1480 			    SSTS_DREG_EMPTY) != 0)
   1481 				break;
   1482 			/* Break on interrupt. */
   1483 			if (intstat != 0)
   1484 				goto phasechange;
   1485 			DELAY(1);
   1486 		}
   1487 
   1488 		xfer = min(DOUTAMOUNT, n);
   1489 
   1490 		SPC_MISC(("%d> ", xfer));
   1491 
   1492 		n -= xfer;
   1493 		out += xfer;
   1494 
   1495 		bus_space_write_multi_1(iot, ioh, DREG, p, xfer);
   1496 		p += xfer;
   1497 	}
   1498 
   1499 	if (out == 0) {
   1500 		for (;;) {
   1501 			if (bus_space_read_1(iot, ioh, INTS) != 0)
   1502 				break;
   1503 			DELAY(1);
   1504 		}
   1505 		SPC_MISC(("extra data  "));
   1506 	} else {
   1507 		/* See the bytes off chip */
   1508 		for (;;) {
   1509 			/* Wait till buffer is empty. */
   1510 			if ((bus_space_read_1(iot, ioh, SSTS) &
   1511 			    SSTS_DREG_EMPTY) != 0)
   1512 				break;
   1513 			intstat = bus_space_read_1(iot, ioh, INTS);
   1514 			/* Break on interrupt. */
   1515 			if (intstat != 0)
   1516 				goto phasechange;
   1517 			DELAY(1);
   1518 		}
   1519 	}
   1520 
   1521 phasechange:
   1522 	/* Stop the FIFO data path. */
   1523 
   1524 	if (intstat != 0) {
   1525 		/* Some sort of phase change. */
   1526 		int amount;
   1527 
   1528 		amount = (bus_space_read_1(iot, ioh, TCH) << 16) |
   1529 		    (bus_space_read_1(iot, ioh, TCM) << 8) |
   1530 		    bus_space_read_1(iot, ioh, TCL);
   1531 		if (amount > 0) {
   1532 			out -= amount;
   1533 			SPC_MISC(("+%d ", amount));
   1534 		}
   1535 	}
   1536 
   1537 	return out;
   1538 }
   1539 
   1540 /*
   1541  * spc_datain_pio: perform data transfers using the FIFO datapath in the spc
   1542  * Precondition: The SCSI bus should be in the DIN phase, with REQ asserted
   1543  * and ACK deasserted (i.e. at least one byte is ready).
   1544  *
   1545  * For now, uses a pretty dumb algorithm, hangs around until all data has been
   1546  * transferred.  This, is OK for fast targets, but not so smart for slow
   1547  * targets which don't disconnect or for huge transfers.
   1548  */
   1549 int
   1550 spc_datain_pio(struct spc_softc *sc, u_char *p, int n)
   1551 {
   1552 	bus_space_tag_t iot = sc->sc_iot;
   1553 	bus_space_handle_t ioh = sc->sc_ioh;
   1554 	int in = 0;
   1555 	u_int8_t intstat, sstat;
   1556 #define DINAMOUNT 8		/* Full FIFO */
   1557 
   1558 	SPC_TRACE(("spc_datain_pio  "));
   1559 	/* send TRANSFER command. */
   1560 	bus_space_write_1(iot, ioh, TCH, n >> 16);
   1561 	bus_space_write_1(iot, ioh, TCM, n >> 8);
   1562 	bus_space_write_1(iot, ioh, TCL, n);
   1563 	bus_space_write_1(iot, ioh, PCTL, sc->sc_phase | PCTL_BFINT_ENAB);
   1564 #ifdef NEED_DREQ_ON_HARDWARE_XFER
   1565 	bus_space_write_1(iot, ioh, SCMD, SCMD_XFR);	/* XXX */
   1566 #else
   1567 	bus_space_write_1(iot, ioh, SCMD,
   1568 	    SCMD_XFR | SCMD_PROG_XFR);	/* XXX */
   1569 #endif
   1570 
   1571 	/*
   1572 	 * We leave this loop if one or more of the following is true:
   1573 	 * a) phase != PH_DATAIN && FIFOs are empty
   1574 	 * b) reset has occurred or busfree is detected.
   1575 	 */
   1576 	intstat = 0;
   1577 	while (n > 0) {
   1578 		sstat = bus_space_read_1(iot, ioh, SSTS);
   1579 		if ((sstat & SSTS_DREG_FULL) != 0) {
   1580 			n -= DINAMOUNT;
   1581 			in += DINAMOUNT;
   1582 			bus_space_read_multi_1(iot, ioh, DREG, p, DINAMOUNT);
   1583 			p += DINAMOUNT;
   1584 		} else if ((sstat & SSTS_DREG_EMPTY) == 0) {
   1585 			n--;
   1586 			in++;
   1587 			*p++ = bus_space_read_1(iot, ioh, DREG);
   1588 		} else {
   1589 			if (intstat != 0)
   1590 				goto phasechange;
   1591 			intstat = bus_space_read_1(iot, ioh, INTS);
   1592 		}
   1593 	}
   1594 
   1595 	/*
   1596 	 * Some SCSI-devices are rude enough to transfer more data than what
   1597 	 * was requested, e.g. 2048 bytes from a CD-ROM instead of the
   1598 	 * requested 512.  Test for progress, i.e. real transfers.  If no real
   1599 	 * transfers have been performed (n is probably already zero) and the
   1600 	 * FIFO is not empty, waste some bytes....
   1601 	 */
   1602 	if (in == 0) {
   1603 		for (;;) {
   1604 			sstat = bus_space_read_1(iot, ioh, SSTS);
   1605 			if ((sstat & SSTS_DREG_EMPTY) == 0) {
   1606 				(void) bus_space_read_1(iot, ioh, DREG);
   1607 			} else {
   1608 				if (intstat != 0)
   1609 					goto phasechange;
   1610 				intstat = bus_space_read_1(iot, ioh, INTS);
   1611 			}
   1612 			DELAY(1);
   1613 		}
   1614 		SPC_MISC(("extra data  "));
   1615 	}
   1616 
   1617 phasechange:
   1618 	/* Stop the FIFO data path. */
   1619 
   1620 	return in;
   1621 }
   1622 
   1623 /*
   1624  * Catch an interrupt from the adaptor
   1625  */
   1626 /*
   1627  * This is the workhorse routine of the driver.
   1628  * Deficiencies (for now):
   1629  * 1) always uses programmed I/O
   1630  */
   1631 int
   1632 spc_intr(void *arg)
   1633 {
   1634 	struct spc_softc *sc = arg;
   1635 	bus_space_tag_t iot = sc->sc_iot;
   1636 	bus_space_handle_t ioh = sc->sc_ioh;
   1637 	u_char ints;
   1638 	struct spc_acb *acb;
   1639 	struct scsipi_periph *periph;
   1640 	struct spc_tinfo *ti;
   1641 	int n;
   1642 
   1643 	SPC_TRACE(("spc_intr  "));
   1644 
   1645 	ints = bus_space_read_1(iot, ioh, INTS);
   1646 	if (ints == 0)
   1647 		return 0;
   1648 
   1649 	/*
   1650 	 * Disable interrupt.
   1651 	 */
   1652 	bus_space_write_1(iot, ioh, SCTL,
   1653 	    bus_space_read_1(iot, ioh, SCTL) & ~SCTL_INTR_ENAB);
   1654 
   1655 	if (sc->sc_dma_done != NULL &&
   1656 	    sc->sc_state == SPC_CONNECTED &&
   1657 	    (sc->sc_flags & SPC_DOINGDMA) != 0 &&
   1658 	    (sc->sc_phase == PH_DATAOUT || sc->sc_phase == PH_DATAIN)) {
   1659 		(*sc->sc_dma_done)(sc);
   1660 	}
   1661 
   1662 loop:
   1663 	/*
   1664 	 * Loop until transfer completion.
   1665 	 */
   1666 	/*
   1667 	 * First check for abnormal conditions, such as reset.
   1668 	 */
   1669 	ints = bus_space_read_1(iot, ioh, INTS);
   1670 	SPC_MISC(("ints = 0x%x  ", ints));
   1671 
   1672 	if ((ints & INTS_RST) != 0) {
   1673 		printf("%s: SCSI bus reset\n", sc->sc_dev.dv_xname);
   1674 		goto reset;
   1675 	}
   1676 
   1677 	/*
   1678 	 * Check for less serious errors.
   1679 	 */
   1680 	if ((bus_space_read_1(iot, ioh, SERR) & (SERR_SCSI_PAR|SERR_SPC_PAR))
   1681 	    != 0) {
   1682 		printf("%s: SCSI bus parity error\n", sc->sc_dev.dv_xname);
   1683 		if (sc->sc_prevphase == PH_MSGIN) {
   1684 			sc->sc_flags |= SPC_DROP_MSGIN;
   1685 			spc_sched_msgout(sc, SEND_PARITY_ERROR);
   1686 		} else
   1687 			spc_sched_msgout(sc, SEND_INIT_DET_ERR);
   1688 	}
   1689 
   1690 	/*
   1691 	 * If we're not already busy doing something test for the following
   1692 	 * conditions:
   1693 	 * 1) We have been reselected by something
   1694 	 * 2) We have selected something successfully
   1695 	 * 3) Our selection process has timed out
   1696 	 * 4) This is really a bus free interrupt just to get a new command
   1697 	 *    going?
   1698 	 * 5) Spurious interrupt?
   1699 	 */
   1700 	switch (sc->sc_state) {
   1701 	case SPC_IDLE:
   1702 	case SPC_SELECTING:
   1703 		SPC_MISC(("ints:0x%02x ", ints));
   1704 
   1705 		if ((ints & INTS_SEL) != 0) {
   1706 			/*
   1707 			 * We don't currently support target mode.
   1708 			 */
   1709 			printf("%s: target mode selected; going to BUS FREE\n",
   1710 			    sc->sc_dev.dv_xname);
   1711 
   1712 			goto sched;
   1713 		} else if ((ints & INTS_RESEL) != 0) {
   1714 			SPC_MISC(("reselected  "));
   1715 
   1716 			/*
   1717 			 * If we're trying to select a target ourselves,
   1718 			 * push our command back into the ready list.
   1719 			 */
   1720 			if (sc->sc_state == SPC_SELECTING) {
   1721 				SPC_MISC(("backoff selector  "));
   1722 				SPC_ASSERT(sc->sc_nexus != NULL);
   1723 				acb = sc->sc_nexus;
   1724 				sc->sc_nexus = NULL;
   1725 				TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
   1726 			}
   1727 
   1728 			/* Save reselection ID. */
   1729 			sc->sc_selid = bus_space_read_1(iot, ioh, TEMP);
   1730 
   1731 			sc->sc_state = SPC_RESELECTED;
   1732 		} else if ((ints & INTS_CMD_DONE) != 0) {
   1733 			SPC_MISC(("selected  "));
   1734 
   1735 			/*
   1736 			 * We have selected a target. Things to do:
   1737 			 * a) Determine what message(s) to send.
   1738 			 * b) Verify that we're still selecting the target.
   1739 			 * c) Mark device as busy.
   1740 			 */
   1741 			if (sc->sc_state != SPC_SELECTING) {
   1742 				printf("%s: selection out while idle; "
   1743 				    "resetting\n", sc->sc_dev.dv_xname);
   1744 				SPC_BREAK();
   1745 				goto reset;
   1746 			}
   1747 			SPC_ASSERT(sc->sc_nexus != NULL);
   1748 			acb = sc->sc_nexus;
   1749 			periph = acb->xs->xs_periph;
   1750 			ti = &sc->sc_tinfo[periph->periph_target];
   1751 
   1752 			sc->sc_msgpriq = SEND_IDENTIFY;
   1753 			if (acb->flags & ACB_RESET)
   1754 				sc->sc_msgpriq |= SEND_DEV_RESET;
   1755 			else if (acb->flags & ACB_ABORT)
   1756 				sc->sc_msgpriq |= SEND_ABORT;
   1757 			else {
   1758 #if SPC_USE_SYNCHRONOUS
   1759 				if ((ti->flags & DO_SYNC) != 0)
   1760 					sc->sc_msgpriq |= SEND_SDTR;
   1761 #endif
   1762 #if SPC_USE_WIDE
   1763 				if ((ti->flags & DO_WIDE) != 0)
   1764 					sc->sc_msgpriq |= SEND_WDTR;
   1765 #endif
   1766 			}
   1767 
   1768 			acb->flags |= ACB_NEXUS;
   1769 			ti->lubusy |= (1 << periph->periph_lun);
   1770 
   1771 			/* Do an implicit RESTORE POINTERS. */
   1772 			sc->sc_dp = acb->data_addr;
   1773 			sc->sc_dleft = acb->data_length;
   1774 			sc->sc_cp = (u_char *)&acb->scsipi_cmd;
   1775 			sc->sc_cleft = acb->scsipi_cmd_length;
   1776 
   1777 			/* On our first connection, schedule a timeout. */
   1778 			if ((acb->xs->xs_control & XS_CTL_POLL) == 0)
   1779 				callout_reset(&acb->xs->xs_callout,
   1780 				    mstohz(acb->timeout), spc_timeout, acb);
   1781 
   1782 			sc->sc_state = SPC_CONNECTED;
   1783 		} else if ((ints & INTS_TIMEOUT) != 0) {
   1784 			SPC_MISC(("selection timeout  "));
   1785 
   1786 			if (sc->sc_state != SPC_SELECTING) {
   1787 				printf("%s: selection timeout while idle; "
   1788 				    "resetting\n", sc->sc_dev.dv_xname);
   1789 				SPC_BREAK();
   1790 				goto reset;
   1791 			}
   1792 			SPC_ASSERT(sc->sc_nexus != NULL);
   1793 			acb = sc->sc_nexus;
   1794 
   1795 			delay(250);
   1796 
   1797 			acb->xs->error = XS_SELTIMEOUT;
   1798 			goto finish;
   1799 		} else {
   1800 			if (sc->sc_state != SPC_IDLE) {
   1801 				printf("%s: BUS FREE while not idle; "
   1802 				    "state=%d\n",
   1803 				    sc->sc_dev.dv_xname, sc->sc_state);
   1804 				SPC_BREAK();
   1805 				goto out;
   1806 			}
   1807 
   1808 			goto sched;
   1809 		}
   1810 
   1811 		/*
   1812 		 * Turn off selection stuff, and prepare to catch bus free
   1813 		 * interrupts, parity errors, and phase changes.
   1814 		 */
   1815 
   1816 		sc->sc_flags = 0;
   1817 		sc->sc_prevphase = PH_INVALID;
   1818 		goto dophase;
   1819 	}
   1820 
   1821 	if ((ints & INTS_DISCON) != 0) {
   1822 		/* We've gone to BUS FREE phase. */
   1823 		/* disable disconnect interrupt */
   1824 		bus_space_write_1(iot, ioh, PCTL,
   1825 		    bus_space_read_1(iot, ioh, PCTL) & ~PCTL_BFINT_ENAB);
   1826 		/* XXX reset interrput */
   1827 		bus_space_write_1(iot, ioh, INTS, ints);
   1828 
   1829 		switch (sc->sc_state) {
   1830 		case SPC_RESELECTED:
   1831 			goto sched;
   1832 
   1833 		case SPC_CONNECTED:
   1834 			SPC_ASSERT(sc->sc_nexus != NULL);
   1835 			acb = sc->sc_nexus;
   1836 
   1837 #if SPC_USE_SYNCHRONOUS + SPC_USE_WIDE
   1838 			if (sc->sc_prevphase == PH_MSGOUT) {
   1839 				/*
   1840 				 * If the target went to BUS FREE phase during
   1841 				 * or immediately after sending a SDTR or WDTR
   1842 				 * message, disable negotiation.
   1843 				 */
   1844 				periph = acb->xs->xs_periph;
   1845 				ti = &sc->sc_tinfo[periph->periph_target];
   1846 				switch (sc->sc_lastmsg) {
   1847 #if SPC_USE_SYNCHRONOUS
   1848 				case SEND_SDTR:
   1849 					ti->flags &= ~DO_SYNC;
   1850 					ti->period = ti->offset = 0;
   1851 					break;
   1852 #endif
   1853 #if SPC_USE_WIDE
   1854 				case SEND_WDTR:
   1855 					ti->flags &= ~DO_WIDE;
   1856 					ti->width = 0;
   1857 					break;
   1858 #endif
   1859 				}
   1860 			}
   1861 #endif
   1862 
   1863 			if ((sc->sc_flags & SPC_ABORTING) == 0) {
   1864 				/*
   1865 				 * Section 5.1.1 of the SCSI 2 spec suggests
   1866 				 * issuing a REQUEST SENSE following an
   1867 				 * unexpected disconnect.  Some devices go into
   1868 				 * a contingent allegiance condition when
   1869 				 * disconnecting, and this is necessary to
   1870 				 * clean up their state.
   1871 				 */
   1872 				printf("%s: unexpected disconnect; "
   1873 				    "sending REQUEST SENSE\n",
   1874 				    sc->sc_dev.dv_xname);
   1875 				SPC_BREAK();
   1876 				acb->target_stat = SCSI_CHECK;
   1877 				acb->xs->error = XS_NOERROR;
   1878 				goto finish;
   1879 			}
   1880 
   1881 			acb->xs->error = XS_DRIVER_STUFFUP;
   1882 			goto finish;
   1883 
   1884 		case SPC_DISCONNECT:
   1885 			SPC_ASSERT(sc->sc_nexus != NULL);
   1886 			acb = sc->sc_nexus;
   1887 			TAILQ_INSERT_HEAD(&sc->nexus_list, acb, chain);
   1888 			sc->sc_nexus = NULL;
   1889 			goto sched;
   1890 
   1891 		case SPC_CMDCOMPLETE:
   1892 			SPC_ASSERT(sc->sc_nexus != NULL);
   1893 			acb = sc->sc_nexus;
   1894 			goto finish;
   1895 		}
   1896 	}
   1897 	else if ((ints & INTS_CMD_DONE) != 0 &&
   1898 	    sc->sc_prevphase == PH_MSGIN &&
   1899 	    sc->sc_state != SPC_CONNECTED)
   1900 		goto out;
   1901 
   1902 dophase:
   1903 #if 0
   1904 	if ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) == 0) {
   1905 		/* Wait for REQINIT. */
   1906 		goto out;
   1907 	}
   1908 #else
   1909 	bus_space_write_1(iot, ioh, INTS, ints);
   1910 	ints = 0;
   1911 	while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) == 0)
   1912 		delay(1);	/* need timeout XXX */
   1913 #endif
   1914 
   1915 	/*
   1916 	 * State transition.
   1917 	 */
   1918 	sc->sc_phase = bus_space_read_1(iot, ioh, PSNS) & PH_MASK;
   1919 #if 0
   1920 	bus_space_write_1(iot, ioh, PCTL, sc->sc_phase);
   1921 #endif
   1922 
   1923 	SPC_MISC(("phase=%d\n", sc->sc_phase));
   1924 	switch (sc->sc_phase) {
   1925 	case PH_MSGOUT:
   1926 		if (sc->sc_state != SPC_CONNECTED &&
   1927 		    sc->sc_state != SPC_RESELECTED)
   1928 			break;
   1929 		spc_msgout(sc);
   1930 		sc->sc_prevphase = PH_MSGOUT;
   1931 		goto loop;
   1932 
   1933 	case PH_MSGIN:
   1934 		if (sc->sc_state != SPC_CONNECTED &&
   1935 		    sc->sc_state != SPC_RESELECTED)
   1936 			break;
   1937 		spc_msgin(sc);
   1938 		sc->sc_prevphase = PH_MSGIN;
   1939 		goto loop;
   1940 
   1941 	case PH_CMD:
   1942 		if (sc->sc_state != SPC_CONNECTED)
   1943 			break;
   1944 #if SPC_DEBUG
   1945 		if ((spc_debug & SPC_SHOWMISC) != 0) {
   1946 			SPC_ASSERT(sc->sc_nexus != NULL);
   1947 			acb = sc->sc_nexus;
   1948 			printf("cmd=0x%02x+%d  ",
   1949 			    acb->scsipi_cmd.opcode, acb->scsipi_cmd_length - 1);
   1950 		}
   1951 #endif
   1952 		n = spc_dataout_pio(sc, sc->sc_cp, sc->sc_cleft);
   1953 		sc->sc_cp += n;
   1954 		sc->sc_cleft -= n;
   1955 		sc->sc_prevphase = PH_CMD;
   1956 		goto loop;
   1957 
   1958 	case PH_DATAOUT:
   1959 		if (sc->sc_state != SPC_CONNECTED)
   1960 			break;
   1961 		SPC_MISC(("dataout dleft=%d  ", sc->sc_dleft));
   1962 		if (sc->sc_dma_start != NULL &&
   1963 		    sc->sc_dleft > SPC_MIN_DMA_LEN) {
   1964 			(*sc->sc_dma_start)(sc, sc->sc_dp, sc->sc_dleft, 0);
   1965 			sc->sc_prevphase = PH_DATAOUT;
   1966 			goto out;
   1967 		}
   1968 		n = spc_dataout_pio(sc, sc->sc_dp, sc->sc_dleft);
   1969 		sc->sc_dp += n;
   1970 		sc->sc_dleft -= n;
   1971 		sc->sc_prevphase = PH_DATAOUT;
   1972 		goto loop;
   1973 
   1974 	case PH_DATAIN:
   1975 		if (sc->sc_state != SPC_CONNECTED)
   1976 			break;
   1977 		SPC_MISC(("datain  "));
   1978 		if (sc->sc_dma_start != NULL &&
   1979 		    sc->sc_dleft > SPC_MIN_DMA_LEN) {
   1980 			(*sc->sc_dma_start)(sc, sc->sc_dp, sc->sc_dleft, 1);
   1981 			sc->sc_prevphase = PH_DATAIN;
   1982 			goto out;
   1983 		}
   1984 		n = spc_datain_pio(sc, sc->sc_dp, sc->sc_dleft);
   1985 		sc->sc_dp += n;
   1986 		sc->sc_dleft -= n;
   1987 		sc->sc_prevphase = PH_DATAIN;
   1988 		goto loop;
   1989 
   1990 	case PH_STAT:
   1991 		if (sc->sc_state != SPC_CONNECTED)
   1992 			break;
   1993 		SPC_ASSERT(sc->sc_nexus != NULL);
   1994 		acb = sc->sc_nexus;
   1995 
   1996 		if ((bus_space_read_1(iot, ioh, PSNS) & PSNS_ATN) != 0)
   1997 			bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ATN);
   1998 		bus_space_write_1(iot, ioh, PCTL, PCTL_BFINT_ENAB | PH_STAT);
   1999 		while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) == 0)
   2000 			DELAY(1);	/* XXX needs timeout */
   2001 		acb->target_stat = bus_space_read_1(iot, ioh, TEMP);
   2002 		bus_space_write_1(iot, ioh, SCMD, SCMD_SET_ACK);
   2003 		while ((bus_space_read_1(iot, ioh, PSNS) & PSNS_REQ) != 0)
   2004 			DELAY(1);	/* XXX needs timeout */
   2005 		bus_space_write_1(iot, ioh, SCMD, SCMD_RST_ACK);
   2006 
   2007 		SPC_MISC(("target_stat=0x%02x  ", acb->target_stat));
   2008 		sc->sc_prevphase = PH_STAT;
   2009 		goto loop;
   2010 	}
   2011 
   2012 	printf("%s: unexpected bus phase; resetting\n", sc->sc_dev.dv_xname);
   2013 	SPC_BREAK();
   2014 reset:
   2015 	spc_init(sc, 1);
   2016 	return 1;
   2017 
   2018 finish:
   2019 	callout_stop(&acb->xs->xs_callout);
   2020 	bus_space_write_1(iot, ioh, INTS, ints);
   2021 	ints = 0;
   2022 	spc_done(sc, acb);
   2023 	goto out;
   2024 
   2025 sched:
   2026 	sc->sc_state = SPC_IDLE;
   2027 	spc_sched(sc);
   2028 	goto out;
   2029 
   2030 out:
   2031 	if (ints)
   2032 		bus_space_write_1(iot, ioh, INTS, ints);
   2033 	bus_space_write_1(iot, ioh, SCTL,
   2034 	    bus_space_read_1(iot, ioh, SCTL) | SCTL_INTR_ENAB);
   2035 	return 1;
   2036 }
   2037 
   2038 void
   2039 spc_abort(struct spc_softc *sc, struct spc_acb *acb)
   2040 {
   2041 
   2042 	/* 2 secs for the abort */
   2043 	acb->timeout = SPC_ABORT_TIMEOUT;
   2044 	acb->flags |= ACB_ABORT;
   2045 
   2046 	if (acb == sc->sc_nexus) {
   2047 		/*
   2048 		 * If we're still selecting, the message will be scheduled
   2049 		 * after selection is complete.
   2050 		 */
   2051 		if (sc->sc_state == SPC_CONNECTED)
   2052 			spc_sched_msgout(sc, SEND_ABORT);
   2053 	} else {
   2054 		spc_dequeue(sc, acb);
   2055 		TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
   2056 		if (sc->sc_state == SPC_IDLE)
   2057 			spc_sched(sc);
   2058 	}
   2059 }
   2060 
   2061 void
   2062 spc_timeout(void *arg)
   2063 {
   2064 	struct spc_acb *acb = arg;
   2065 	struct scsipi_xfer *xs = acb->xs;
   2066 	struct scsipi_periph *periph = xs->xs_periph;
   2067 	struct spc_softc *sc;
   2068 	int s;
   2069 
   2070 	sc = (void *)periph->periph_channel->chan_adapter->adapt_dev;
   2071 	scsipi_printaddr(periph);
   2072 	printf("timed out");
   2073 
   2074 	s = splbio();
   2075 
   2076 	if (acb->flags & ACB_ABORT) {
   2077 		/* abort timed out */
   2078 		printf(" AGAIN\n");
   2079 		/* XXX Must reset! */
   2080 	} else {
   2081 		/* abort the operation that has timed out */
   2082 		printf("\n");
   2083 		acb->xs->error = XS_TIMEOUT;
   2084 		spc_abort(sc, acb);
   2085 	}
   2086 
   2087 	splx(s);
   2088 }
   2089 
   2090 #ifdef SPC_DEBUG
   2091 /*
   2092  * The following functions are mostly used for debugging purposes, either
   2093  * directly called from the driver or from the kernel debugger.
   2094  */
   2095 
   2096 void
   2097 spc_show_scsi_cmd(struct spc_acb *acb)
   2098 {
   2099 	u_char  *b = (u_char *)&acb->scsipi_cmd;
   2100 	int i;
   2101 
   2102 	scsipi_printaddr(acb->xs->xs_periph);
   2103 	if ((acb->xs->xs_control & XS_CTL_RESET) == 0) {
   2104 		for (i = 0; i < acb->scsipi_cmd_length; i++) {
   2105 			if (i)
   2106 				printf(",");
   2107 			printf("%x", b[i]);
   2108 		}
   2109 		printf("\n");
   2110 	} else
   2111 		printf("RESET\n");
   2112 }
   2113 
   2114 void
   2115 spc_print_acb(struct spc_acb *acb)
   2116 {
   2117 
   2118 	printf("acb@%p xs=%p flags=%x", acb, acb->xs, acb->flags);
   2119 	printf(" dp=%p dleft=%d target_stat=%x\n",
   2120 	    acb->data_addr, acb->data_length, acb->target_stat);
   2121 	spc_show_scsi_cmd(acb);
   2122 }
   2123 
   2124 void
   2125 spc_print_active_acb(void)
   2126 {
   2127 	struct spc_acb *acb;
   2128 	struct spc_softc *sc = spc_cd.cd_devs[0]; /* XXX */
   2129 
   2130 	printf("ready list:\n");
   2131 	TAILQ_FOREACH(acb, &sc->ready_list, chain)
   2132 		spc_print_acb(acb);
   2133 	printf("nexus:\n");
   2134 	if (sc->sc_nexus != NULL)
   2135 		spc_print_acb(sc->sc_nexus);
   2136 	printf("nexus list:\n");
   2137 	TAILQ_FOREACH(acb, &sc->nexus_list, chain)
   2138 		spc_print_acb(acb);
   2139 }
   2140 
   2141 void
   2142 spc_dump89352(struct spc_softc *sc)
   2143 {
   2144 	bus_space_tag_t iot = sc->sc_iot;
   2145 	bus_space_handle_t ioh = sc->sc_ioh;
   2146 
   2147 	printf("mb89352: BDID=%x SCTL=%x SCMD=%x TMOD=%x\n",
   2148 	    bus_space_read_1(iot, ioh, BDID),
   2149 	    bus_space_read_1(iot, ioh, SCTL),
   2150 	    bus_space_read_1(iot, ioh, SCMD),
   2151 	    bus_space_read_1(iot, ioh, TMOD));
   2152 	printf("         INTS=%x PSNS=%x SSTS=%x SERR=%x PCTL=%x\n",
   2153 	    bus_space_read_1(iot, ioh, INTS),
   2154 	    bus_space_read_1(iot, ioh, PSNS),
   2155 	    bus_space_read_1(iot, ioh, SSTS),
   2156 	    bus_space_read_1(iot, ioh, SERR),
   2157 	    bus_space_read_1(iot, ioh, PCTL));
   2158 	printf("         MBC=%x DREG=%x TEMP=%x TCH=%x TCM=%x\n",
   2159 	    bus_space_read_1(iot, ioh, MBC),
   2160 #if 0
   2161 	    bus_space_read_1(iot, ioh, DREG),
   2162 #else
   2163 	    0,
   2164 #endif
   2165 	    bus_space_read_1(iot, ioh, TEMP),
   2166 	    bus_space_read_1(iot, ioh, TCH),
   2167 	    bus_space_read_1(iot, ioh, TCM));
   2168 	printf("         TCL=%x EXBF=%x\n",
   2169 	    bus_space_read_1(iot, ioh, TCL),
   2170 	    bus_space_read_1(iot, ioh, EXBF));
   2171 }
   2172 
   2173 void
   2174 spc_dump_driver(struct spc_softc *sc)
   2175 {
   2176 	struct spc_tinfo *ti;
   2177 	int i;
   2178 
   2179 	printf("nexus=%p prevphase=%x\n", sc->sc_nexus, sc->sc_prevphase);
   2180 	printf("state=%x msgin=%x msgpriq=%x msgoutq=%x lastmsg=%x "
   2181 	    "currmsg=%x\n", sc->sc_state, sc->sc_imess[0],
   2182 	    sc->sc_msgpriq, sc->sc_msgoutq, sc->sc_lastmsg, sc->sc_currmsg);
   2183 	for (i = 0; i < 7; i++) {
   2184 		ti = &sc->sc_tinfo[i];
   2185 		printf("tinfo%d: %d cmds %d disconnects %d timeouts",
   2186 		    i, ti->cmds, ti->dconns, ti->touts);
   2187 		printf(" %d senses flags=%x\n", ti->senses, ti->flags);
   2188 	}
   2189 }
   2190 #endif
   2191