Home | History | Annotate | Line # | Download | only in dev
mac68k5380.c revision 1.19
      1 /*	$NetBSD: mac68k5380.c,v 1.19 1996/02/19 02:51:03 briggs Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1995 Allen Briggs
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *      This product includes software developed by Allen Briggs
     18  * 4. The name of the author may not be used to endorse or promote products
     19  *    derived from this software without specific prior written permission
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     31  *
     32  * Derived from atari5380.c for the mac68k port of NetBSD.
     33  *
     34  */
     35 
     36 #include <sys/param.h>
     37 #include <sys/systm.h>
     38 #include <sys/kernel.h>
     39 #include <sys/device.h>
     40 #include <sys/dkstat.h>
     41 #include <sys/syslog.h>
     42 #include <sys/buf.h>
     43 #include <scsi/scsi_all.h>
     44 #include <scsi/scsi_message.h>
     45 #include <scsi/scsiconf.h>
     46 
     47 /*
     48  * Include the driver definitions
     49  */
     50 #include <mac68k/dev/ncr5380reg.h>
     51 
     52 #include <machine/stdarg.h>
     53 
     54 #include "../mac68k/via.h"
     55 
     56 /*
     57  * Set the various driver options
     58  */
     59 #define	NREQ		18	/* Size of issue queue			*/
     60 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
     61 
     62 #define	DRNAME		ncrscsi	/* used in various prints	*/
     63 #undef	DBG_SEL			/* Show the selection process		*/
     64 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
     65 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
     66 #undef	DBG_PIO			/* Show the polled-I/O process		*/
     67 #undef	DBG_INF			/* Show information transfer process	*/
     68 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
     69 #define	DBG_PID		25	/* Keep track of driver			*/
     70 #ifdef DBG_NOSTATIC
     71 #	define	static
     72 #endif
     73 #ifdef DBG_SEL
     74 #	define	DBG_SELPRINT(a,b)	printf(a,b)
     75 #else
     76 #	define DBG_SELPRINT(a,b)
     77 #endif
     78 #ifdef DBG_PIO
     79 #	define DBG_PIOPRINT(a,b,c) 	printf(a,b,c)
     80 #else
     81 #	define DBG_PIOPRINT(a,b,c)
     82 #endif
     83 #ifdef DBG_INF
     84 #	define DBG_INFPRINT(a,b,c)	a(b,c)
     85 #else
     86 #	define DBG_INFPRINT(a,b,c)
     87 #endif
     88 #ifdef DBG_PID
     89 	/* static	char	*last_hit = NULL, *olast_hit = NULL; */
     90 	static char *last_hit[DBG_PID];
     91 #	define	PID(a)	\
     92 	{ int i; \
     93 	  for (i=0; i< DBG_PID-1; i++) \
     94 		last_hit[i] = last_hit[i+1]; \
     95 	  last_hit[DBG_PID-1] = a; }
     96 #else
     97 #	define	PID(a)
     98 #endif
     99 
    100 #undef 	REAL_DMA		/* Use DMA if sensible			*/
    101 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
    102 #define fair_to_keep_dma()	1
    103 #define claimed_dma()		1
    104 #define reconsider_dma()
    105 #define	USE_PDMA	1	/* Use special pdma-transfer function	*/
    106 #define MIN_PHYS	0x2000	/* pdma space w/ /DSACK is only 0x2000  */
    107 
    108 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
    109 
    110 /*
    111  * softc of currently active controller (well, we only have one for now).
    112  */
    113 
    114 static struct ncr_softc	*cur_softc;
    115 
    116 struct scsi_5380 {
    117 	volatile u_char	scsi_5380[8*16]; /* 8 regs, 1 every 16th byte. */
    118 };
    119 
    120 extern vm_offset_t	SCSIBase;
    121 static volatile u_char	*ncr		= (volatile u_char *) 0x10000;
    122 static volatile u_char	*ncr_5380_with_drq	= (volatile u_char *)  0x6000;
    123 static volatile u_char	*ncr_5380_without_drq	= (volatile u_char *) 0x12000;
    124 
    125 static volatile u_char	*scsi_enable		= NULL;
    126 
    127 #define SCSI_5380		((struct scsi_5380 *) ncr)
    128 #define GET_5380_REG(rnum)	SCSI_5380->scsi_5380[((rnum)<<4)]
    129 #define SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[((rnum)<<4)] = (val))
    130 
    131 void	ncr5380_irq_intr(void *);
    132 void	ncr5380_drq_intr(void *);
    133 
    134 static __inline__ void
    135 scsi_clr_ipend()
    136 {
    137 	int	tmp;
    138 
    139 	tmp = GET_5380_REG(NCR5380_IRCV);
    140 }
    141 
    142 extern __inline__ void
    143 scsi_ienable()
    144 {
    145 	int	s;
    146 
    147 	s = splhigh();
    148 	*scsi_enable = 0x80 | (V2IF_SCSIIRQ | V2IF_SCSIDRQ);
    149 	splx(s);
    150 }
    151 
    152 extern __inline__ void
    153 scsi_idisable()
    154 {
    155 	int	s;
    156 
    157 	s = splhigh();
    158 	*scsi_enable = V2IF_SCSIIRQ | V2IF_SCSIDRQ;
    159 	splx(s);
    160 }
    161 
    162 static void
    163 scsi_mach_init(sc)
    164 	struct ncr_softc	*sc;
    165 {
    166 	static int	initted = 0;
    167 
    168 	if (initted++)
    169 		panic("scsi_mach_init called again.\n");
    170 
    171 	ncr		= (volatile u_char *)
    172 			  (SCSIBase + (u_long) ncr);
    173 	ncr_5380_with_drq	= (volatile u_char *)
    174 			  (SCSIBase + (u_int) ncr_5380_with_drq);
    175 	ncr_5380_without_drq	= (volatile u_char *)
    176 			  (SCSIBase + (u_int) ncr_5380_without_drq);
    177 
    178 	if (VIA2 == VIA2OFF)
    179 		scsi_enable = Via1Base + VIA2 * 0x2000 + vIER;
    180 	else
    181 		scsi_enable = Via1Base + VIA2 * 0x2000 + rIER;
    182 
    183 	mac68k_register_scsi_irq(ncr5380_irq_intr, sc);
    184 	mac68k_register_scsi_drq(ncr5380_drq_intr, sc);
    185 }
    186 
    187 static int
    188 machine_match(pdp, cdp, auxp, cd)
    189 	struct device	*pdp;
    190 	struct cfdata	*cdp;
    191 	void		*auxp;
    192 	struct cfdriver	*cd;
    193 {
    194 	if (matchbyname(pdp, cdp, auxp) == 0)
    195 		return 0;
    196 	if (!mac68k_machine.scsi80)
    197 		return 0;
    198 	if (cdp->cf_unit != 0)
    199 		return 0;
    200 	return 1;
    201 }
    202 
    203 #if USE_PDMA
    204 int	pdma_5380_dir = 0;
    205 
    206 u_char	*pending_5380_data;
    207 u_long	pending_5380_count;
    208 
    209 #define NCR5380_PDMA_DEBUG 1 	/* Maybe we try with this off eventually. */
    210 
    211 #if NCR5380_PDMA_DEBUG
    212 int		pdma_5380_sends = 0;
    213 int		pdma_5380_bytes = 0;
    214 
    215 void
    216 pdma_stat()
    217 {
    218 	printf("PDMA SCSI: %d xfers completed for %d bytes.\n",
    219 		pdma_5380_sends, pdma_5380_bytes);
    220 	printf("pdma_5380_dir = %d\t",
    221 		pdma_5380_dir);
    222 	printf("datap = 0x%x, remainder = %d.\n",
    223 		pending_5380_data, pending_5380_count);
    224 	scsi_show();
    225 }
    226 #endif
    227 
    228 void
    229 pdma_cleanup(void)
    230 {
    231 	SC_REQ	*reqp = connected;
    232 	int	bytes, s;
    233 
    234 	s = splbio();
    235 	PID("pdma_cleanup0");
    236 
    237 	pdma_5380_dir = 0;
    238 
    239 #if NCR5380_PDMA_DEBUG
    240 	pdma_5380_sends++;
    241 	pdma_5380_bytes+=(reqp->xdata_len - pending_5380_count);
    242 #endif
    243 
    244 	/*
    245 	 * Update pointers.
    246 	 */
    247 	reqp->xdata_ptr += reqp->xdata_len - pending_5380_count;
    248 	reqp->xdata_len  = pending_5380_count;
    249 
    250 	/*
    251 	 * Reset DMA mode.
    252 	 */
    253 	SET_5380_REG(NCR5380_MODE, GET_5380_REG(NCR5380_MODE) & ~SC_M_DMA);
    254 
    255 	/*
    256 	 * Clear any pending interrupts.
    257 	 */
    258 	scsi_clr_ipend();
    259 
    260 	/*
    261 	 * Tell interrupt functions that DMA has ended.
    262 	 */
    263 	reqp->dr_flag &= ~DRIVER_IN_DMA;
    264 
    265 	SET_5380_REG(NCR5380_MODE, IMODE_BASE);
    266 	SET_5380_REG(NCR5380_ICOM, 0);
    267 
    268 	splx(s);
    269 
    270 	/*
    271 	 * Back for more punishment.
    272 	 */
    273 	PID("pdma_cleanup1");
    274 	run_main(cur_softc);
    275 	PID("pdma_cleanup2");
    276 }
    277 #endif
    278 
    279 static __inline__ int
    280 pdma_ready()
    281 {
    282 #if USE_PDMA
    283 	SC_REQ	*reqp = connected;
    284 	int	dmstat, idstat;
    285 extern	u_char	ncr5380_no_parchk;
    286 
    287 	PID("pdma_ready0");
    288 	if (pdma_5380_dir) {
    289 		PID("pdma_ready1.")
    290 		/*
    291 		 * If Mr. IRQ isn't set one might wonder how we got
    292 		 * here.  It does happen, though.
    293 		 */
    294 		dmstat = GET_5380_REG(NCR5380_DMSTAT);
    295 		if (!(dmstat & SC_IRQ_SET)) {
    296 			PID("pdma_ready2");
    297 			return 0;
    298 		}
    299 		/*
    300 		 * For a phase mis-match, ATN is a "don't care," IRQ is 1 and
    301 		 * all other bits in the Bus & Status Register are 0.  Also,
    302 		 * the current SCSI Bus Status Register has a 1 for BSY and
    303 		 * REQ.  Since we're just checking that this interrupt isn't a
    304 		 * reselection or a reset, we just check for either.
    305 		 */
    306 		idstat = GET_5380_REG(NCR5380_IDSTAT);
    307 		if (   ((dmstat & (0xff & ~SC_ATN_STAT)) == SC_IRQ_SET)
    308 		    && ((idstat & (SC_S_BSY|SC_S_REQ))
    309 			== (SC_S_BSY | SC_S_REQ)) ) {
    310 			PID("pdma_ready3");
    311 			pdma_cleanup();
    312 			return 1;
    313 		} else if (PH_IN(reqp->phase) && (dmstat & SC_PAR_ERR)) {
    314 			if (!(ncr5380_no_parchk & (1 << reqp->targ_id)))
    315 				/* XXX: Should be parity error ???? */
    316 				reqp->xs->error = XS_DRIVER_STUFFUP;
    317 			PID("pdma_ready4");
    318 			/* XXX: is this the right reaction? */
    319 			pdma_cleanup();
    320 			return 1;
    321 		} else if (   !(idstat & SC_S_REQ)
    322 			   || (((idstat>>2) & 7) != reqp->phase)) {
    323 #ifdef DIAGNOSTIC
    324 			/* XXX: is this the right reaction? Can this happen? */
    325 			scsi_show();
    326 			printf("Unexpected phase change.\n");
    327 #endif
    328 			reqp->xs->error = XS_DRIVER_STUFFUP;
    329 			pdma_cleanup();
    330 			return 1;
    331 		} else {
    332 			scsi_show();
    333 			panic("Spurious interrupt during PDMA xfer.\n");
    334 		}
    335 	} else
    336 		PID("pdma_ready5");
    337 #endif
    338 	return 0;
    339 }
    340 
    341 void
    342 ncr5380_irq_intr(p)
    343 	void	*p;
    344 {
    345 	struct ncr_softc	*sc = p;
    346 
    347 	PID("irq");
    348 #if USE_PDMA
    349 	if (pdma_ready()) {
    350 		return;
    351 	}
    352 #endif
    353 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
    354 		scsi_idisable();
    355 		ncr_ctrl_intr(cur_softc);
    356 	}
    357 }
    358 
    359 /*
    360  * This is the meat of the PDMA transfer.
    361  * When we get here, we shove data as fast as the mac can take it.
    362  * We depend on several things:
    363  *   * All macs after the Mac Plus that have a 5380 chip should have a general
    364  *     logic IC that handshakes data for blind transfers.
    365  *   * If the SCSI controller finishes sending/receiving data before we do,
    366  *     the same general logic IC will generate a /BERR for us in short order.
    367  *   * The fault address for said /BERR minus the base address for the
    368  *     transfer will be the amount of data that was actually written.
    369  *
    370  * We use the nofault flag and the setjmp/longjmp in locore.s so we can
    371  * detect and handle the bus error for early termination of a command.
    372  * This is usually caused by a disconnecting target.
    373  */
    374 void
    375 ncr5380_drq_intr(p)
    376 	void	*p;
    377 {
    378 #if USE_PDMA
    379 extern	int			*nofault, mac68k_buserr_addr;
    380 	struct ncr_softc	*sc = p;
    381 	label_t			faultbuf;
    382 	register int		count;
    383 	volatile u_int32_t	*long_drq;
    384 	u_int32_t		*long_data;
    385 	volatile u_int8_t	*drq;
    386 	u_int8_t		*data;
    387 
    388 	/*
    389 	 * If we're not ready to xfer data, just return.
    390 	 */
    391 	if (   !(GET_5380_REG(NCR5380_DMSTAT) & SC_DMA_REQ)
    392 	    || !pdma_5380_dir) {
    393 		PID("drq0");
    394 		return;
    395 	}
    396 
    397 	/*
    398 	 * I don't think this should be necessary, but it is
    399 	 * for writes--at least to some devices.  They don't
    400 	 * let go of PH_DATAOUT until we do pdma_cleanup().
    401 	 */
    402 	if (pending_5380_count == 0) {
    403 #if DBG_PID
    404 		if (pdma_5380_dir == 2) {
    405 			PID("drq1 (in)");
    406 		} else {
    407 			PID("drq1 (out)");
    408 		}
    409 #endif
    410 		pdma_cleanup();
    411 		return;
    412 	}
    413 
    414 #if DBG_PID
    415 	if (pdma_5380_dir == 2) {
    416 		PID("drq (in)");
    417 	} else {
    418 		PID("drq (out)");
    419 	}
    420 #endif
    421 
    422 	/*
    423 	 * Setup for a possible bus error caused by SCSI controller
    424 	 * switching out of DATA-IN/OUT before we're done with the
    425 	 * current transfer.
    426 	 */
    427 	nofault = (int *) &faultbuf;
    428 
    429 	if (setjmp((label_t *) nofault)) {
    430 		PID("drq berr");
    431 		nofault = (int *) 0;
    432 		count = (  (u_long) mac68k_buserr_addr
    433 			 - (u_long) ncr_5380_with_drq);
    434 		if ((count < 0) || (count > pending_5380_count)) {
    435 			printf("pdma %s: count = %d (0x%x) (pending "
    436 				"count %d)\n",
    437 				(pdma_5380_dir == 2) ? "in" : "out",
    438 				count, count, pending_5380_count);
    439 			panic("something is wrong");
    440 		}
    441 
    442 		pending_5380_data += count;
    443 		pending_5380_count -= count;
    444 
    445 		PID("end drq early");
    446 		mac68k_buserr_addr = 0;
    447 		return;
    448 	}
    449 
    450 	if (pdma_5380_dir == 2) { /* Data In */
    451 		int	resid;
    452 
    453 		/*
    454 		 * Get the dest address aligned.
    455 		 */
    456 		resid = count = min(pending_5380_count,
    457 				    4 - (((int) pending_5380_data) & 0x3));
    458 		if (count && (count < 4)) {
    459 			data = (u_int8_t *) pending_5380_data;
    460 			drq = (u_int8_t *) ncr_5380_with_drq;
    461 			while (count) {
    462 #define R1	*data++ = *drq++
    463 				R1; count--;
    464 #undef R1
    465 			}
    466 			pending_5380_data += resid;
    467 			pending_5380_count -= resid;
    468 		}
    469 
    470 		/*
    471 		 * Get ready to start the transfer.
    472 		 */
    473 		while (pending_5380_count) {
    474 		int dcount;
    475 
    476 		dcount = count = min(pending_5380_count, MIN_PHYS);
    477 		long_drq = (volatile u_int32_t *) ncr_5380_with_drq;
    478 		long_data = (u_int32_t *) pending_5380_data;
    479 
    480 #define R4	*long_data++ = *long_drq++
    481 		while ( count >= 512 ) {
    482 			if (!(GET_5380_REG(NCR5380_DMSTAT) & SC_DMA_REQ)) {
    483 				nofault = (int *) 0;
    484 
    485 				pending_5380_data += (dcount - count);
    486 				pending_5380_count -= (dcount - count);
    487 				return;
    488 			}
    489 			R4; R4; R4; R4; R4; R4; R4; R4;
    490 			R4; R4; R4; R4; R4; R4; R4; R4;	/* 64 */
    491 			R4; R4; R4; R4; R4; R4; R4; R4;
    492 			R4; R4; R4; R4; R4; R4; R4; R4;	/* 128 */
    493 			R4; R4; R4; R4; R4; R4; R4; R4;
    494 			R4; R4; R4; R4; R4; R4; R4; R4;
    495 			R4; R4; R4; R4; R4; R4; R4; R4;
    496 			R4; R4; R4; R4; R4; R4; R4; R4;	/* 256 */
    497 			R4; R4; R4; R4; R4; R4; R4; R4;
    498 			R4; R4; R4; R4; R4; R4; R4; R4;
    499 			R4; R4; R4; R4; R4; R4; R4; R4;
    500 			R4; R4; R4; R4; R4; R4; R4; R4;
    501 			R4; R4; R4; R4; R4; R4; R4; R4;
    502 			R4; R4; R4; R4; R4; R4; R4; R4;
    503 			R4; R4; R4; R4; R4; R4; R4; R4;
    504 			R4; R4; R4; R4; R4; R4; R4; R4;	/* 512 */
    505 			count -= 512;
    506 		}
    507 		while (count >= 4) {
    508 			R4; count -= 4;
    509 		}
    510 #undef R4
    511 		data = (u_int8_t *) long_data;
    512 		drq = (u_int8_t *) long_drq;
    513 		while (count) {
    514 #define R1	*data++ = *drq++
    515 			R1; count--;
    516 #undef R1
    517 		}
    518 		pending_5380_count -= dcount;
    519 		pending_5380_data += dcount;
    520 		}
    521 	} else {
    522 		int	resid;
    523 
    524 		/*
    525 		 * Get the source address aligned.
    526 		 */
    527 		resid = count = min(pending_5380_count,
    528 				    4 - (((int) pending_5380_data) & 0x3));
    529 		if (count && (count < 4)) {
    530 			data = (u_int8_t *) pending_5380_data;
    531 			drq = (u_int8_t *) ncr_5380_with_drq;
    532 			while (count) {
    533 #define W1	*drq++ = *data++
    534 				W1; count--;
    535 #undef W1
    536 			}
    537 			pending_5380_data += resid;
    538 			pending_5380_count -= resid;
    539 		}
    540 
    541 		/*
    542 		 * Get ready to start the transfer.
    543 		 */
    544 		while (pending_5380_count) {
    545 		int dcount;
    546 
    547 		dcount = count = min(pending_5380_count, MIN_PHYS);
    548 		long_drq = (volatile u_int32_t *) ncr_5380_with_drq;
    549 		long_data = (u_int32_t *) pending_5380_data;
    550 
    551 #define W4	*long_drq++ = *long_data++
    552 		while ( count >= 64 ) {
    553 			W4; W4; W4; W4; W4; W4; W4; W4;
    554 			W4; W4; W4; W4; W4; W4; W4; W4; /*  64 */
    555 			count -= 64;
    556 		}
    557 		while (count >= 4) {
    558 			W4; count -= 4;
    559 		}
    560 #undef W4
    561 		data = (u_int8_t *) long_data;
    562 		drq = (u_int8_t *) long_drq;
    563 		while (count) {
    564 #define W1	*drq++ = *data++
    565 			W1; count--;
    566 #undef W1
    567 		}
    568 		pending_5380_count -= dcount;
    569 		pending_5380_data += dcount;
    570 		}
    571 	}
    572 
    573 	/*
    574 	 * OK.  No bus error occurred above.  Clear the nofault flag
    575 	 * so we no longer short-circuit bus errors.
    576 	 */
    577 	nofault = (int *) 0;
    578 
    579 	PID("end drq");
    580 #endif	/* if USE_PDMA */
    581 }
    582 
    583 #if USE_PDMA
    584 
    585 #define SCSI_TIMEOUT_VAL	10000000
    586 
    587 static int
    588 transfer_pdma(phasep, data, count)
    589 	u_char	*phasep;
    590 	u_char	*data;
    591 	u_long	*count;
    592 {
    593 	SC_REQ	*reqp = connected;
    594 	int	len = *count, i, scsi_timeout = SCSI_TIMEOUT_VAL;
    595 	int	s, err;
    596 
    597 	if (pdma_5380_dir) {
    598 		panic("ncrscsi: transfer_pdma called when operation already "
    599 			"pending.\n");
    600 	}
    601 	PID("transfer_pdma0")
    602 
    603 	/*
    604  	 * Don't bother with PDMA if we can't sleep or for small transfers.
    605  	 */
    606 	if (reqp->dr_flag & DRIVER_NOINT) {
    607 		PID("pdma, falling back to transfer_pio.")
    608 		transfer_pio(phasep, data, count, 0);
    609 		return -1;
    610 	}
    611 
    612 	/*
    613 	 * We are probably already at spl2(), so this is likely a no-op.
    614 	 * Paranoia.
    615 	 */
    616 	s = splbio();
    617 
    618 	scsi_idisable();
    619 
    620 	/*
    621 	 * Match phases with target.
    622 	 */
    623 	SET_5380_REG(NCR5380_TCOM, *phasep);
    624 
    625 	/*
    626 	 * Clear pending interrupts.
    627 	 */
    628 	scsi_clr_ipend();
    629 
    630 	/*
    631 	 * Wait until target asserts BSY.
    632 	 */
    633 	while (    ((GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY) == 0)
    634 		&& (--scsi_timeout) );
    635 	if (!scsi_timeout) {
    636 #if DIAGNOSTIC
    637 		printf("scsi timeout: waiting for BSY in %s.\n",
    638 			(*phasep == PH_DATAOUT) ? "pdma_out" : "pdma_in");
    639 #endif
    640 		goto scsi_timeout_error;
    641 	}
    642 
    643 	/*
    644 	 * Tell the driver that we're in DMA mode.
    645 	 */
    646 	reqp->dr_flag |= DRIVER_IN_DMA;
    647 
    648 	/*
    649 	 * Load transfer values for DRQ interrupt handlers.
    650 	 */
    651 	pending_5380_data = data;
    652 	pending_5380_count = len;
    653 
    654 	/*
    655 	 * Set the transfer function to be called on DRQ interrupts.
    656 	 * And note that we're waiting.
    657 	 */
    658 	switch (*phasep) {
    659 	default:
    660 		panic("Unexpected phase in transfer_pdma.\n");
    661 	case PH_DATAOUT:
    662 		pdma_5380_dir = 1;
    663 		SET_5380_REG(NCR5380_ICOM, GET_5380_REG(NCR5380_ICOM)|SC_ADTB);
    664 		SET_5380_REG(NCR5380_MODE, GET_5380_REG(NCR5380_MODE)|SC_M_DMA);
    665 		SET_5380_REG(NCR5380_DMSTAT, 0);
    666 		break;
    667 	case PH_DATAIN:
    668 		pdma_5380_dir = 2;
    669 		SET_5380_REG(NCR5380_ICOM, 0);
    670 		SET_5380_REG(NCR5380_MODE, GET_5380_REG(NCR5380_MODE)|SC_M_DMA);
    671 		SET_5380_REG(NCR5380_IRCV, 0);
    672 		break;
    673 	}
    674 
    675 	PID("waiting for interrupt.")
    676 
    677 	/*
    678 	 * Now that we're set up, enable interrupts and drop processor
    679 	 * priority back down.
    680 	 */
    681 	scsi_ienable();
    682 	splx(s);
    683 	return 0;
    684 
    685 scsi_timeout_error:
    686 	/*
    687 	 * Clear the DMA mode.
    688 	 */
    689 	SET_5380_REG(NCR5380_MODE, GET_5380_REG(NCR5380_MODE) & ~SC_M_DMA);
    690 	return -1;
    691 }
    692 #endif /* if USE_PDMA */
    693 
    694 /* Include general routines. */
    695 #include <mac68k/dev/ncr5380.c>
    696