xref: /netbsd-src/sys/arch/mac68k/obio/esp.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: esp.c,v 1.25 2000/06/05 07:59:52 nisimura Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Jason R. Thorpe.
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 for the NetBSD Project
18  *	by Jason R. Thorpe.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 1994 Peter Galbavy
36  * All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *	This product includes software developed by Peter Galbavy
49  * 4. The name of the author may not be used to endorse or promote products
50  *    derived from this software without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
53  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
54  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
55  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
56  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
57  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
58  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
60  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
61  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
62  * POSSIBILITY OF SUCH DAMAGE.
63  */
64 
65 /*
66  * Based on aic6360 by Jarle Greipsland
67  *
68  * Acknowledgements: Many of the algorithms used in this driver are
69  * inspired by the work of Julian Elischer (julian@tfs.com) and
70  * Charles Hannum (mycroft@duality.gnu.ai.mit.edu).  Thanks a million!
71  */
72 
73 /*
74  * Initial m68k mac support from Allen Briggs <briggs@macbsd.com>
75  * (basically consisting of the match, a bit of the attach, and the
76  *  "DMA" glue functions).
77  */
78 
79 #include <sys/types.h>
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/kernel.h>
83 #include <sys/errno.h>
84 #include <sys/ioctl.h>
85 #include <sys/device.h>
86 #include <sys/buf.h>
87 #include <sys/proc.h>
88 #include <sys/user.h>
89 #include <sys/queue.h>
90 
91 #include <dev/scsipi/scsi_all.h>
92 #include <dev/scsipi/scsipi_all.h>
93 #include <dev/scsipi/scsiconf.h>
94 #include <dev/scsipi/scsi_message.h>
95 
96 #include <machine/cpu.h>
97 #include <machine/bus.h>
98 #include <machine/param.h>
99 
100 #include <dev/ic/ncr53c9xreg.h>
101 #include <dev/ic/ncr53c9xvar.h>
102 
103 #include <machine/viareg.h>
104 
105 #include <mac68k/obio/espvar.h>
106 #include <mac68k/obio/obiovar.h>
107 
108 void	espattach	__P((struct device *, struct device *, void *));
109 int	espmatch	__P((struct device *, struct cfdata *, void *));
110 
111 /* Linkup to the rest of the kernel */
112 struct cfattach esp_ca = {
113 	sizeof(struct esp_softc), espmatch, espattach
114 };
115 
116 /*
117  * Functions and the switch for the MI code.
118  */
119 u_char	esp_read_reg __P((struct ncr53c9x_softc *, int));
120 void	esp_write_reg __P((struct ncr53c9x_softc *, int, u_char));
121 int	esp_dma_isintr __P((struct ncr53c9x_softc *));
122 void	esp_dma_reset __P((struct ncr53c9x_softc *));
123 int	esp_dma_intr __P((struct ncr53c9x_softc *));
124 int	esp_dma_setup __P((struct ncr53c9x_softc *, caddr_t *,
125 	    size_t *, int, size_t *));
126 void	esp_dma_go __P((struct ncr53c9x_softc *));
127 void	esp_dma_stop __P((struct ncr53c9x_softc *));
128 int	esp_dma_isactive __P((struct ncr53c9x_softc *));
129 void	esp_quick_write_reg __P((struct ncr53c9x_softc *, int, u_char));
130 int	esp_quick_dma_intr __P((struct ncr53c9x_softc *));
131 int	esp_quick_dma_setup __P((struct ncr53c9x_softc *, caddr_t *,
132 	    size_t *, int, size_t *));
133 void	esp_quick_dma_go __P((struct ncr53c9x_softc *));
134 
135 void	esp_intr __P((void *sc));
136 void	esp_dualbus_intr __P((void *sc));
137 static struct esp_softc		*esp0 = NULL, *esp1 = NULL;
138 
139 static __inline__ int esp_dafb_have_dreq __P((struct esp_softc *esc));
140 static __inline__ int esp_iosb_have_dreq __P((struct esp_softc *esc));
141 int (*esp_have_dreq) __P((struct esp_softc *esc));
142 
143 struct ncr53c9x_glue esp_glue = {
144 	esp_read_reg,
145 	esp_write_reg,
146 	esp_dma_isintr,
147 	esp_dma_reset,
148 	esp_dma_intr,
149 	esp_dma_setup,
150 	esp_dma_go,
151 	esp_dma_stop,
152 	esp_dma_isactive,
153 	NULL,			/* gl_clear_latched_intr */
154 };
155 
156 int
157 espmatch(parent, cf, aux)
158 	struct device *parent;
159 	struct cfdata *cf;
160 	void *aux;
161 {
162 	int	found = 0;
163 
164 	if ((cf->cf_unit == 0) && mac68k_machine.scsi96) {
165 		found = 1;
166 	}
167 	if ((cf->cf_unit == 1) && mac68k_machine.scsi96_2) {
168 		found = 1;
169 	}
170 
171 	return found;
172 }
173 
174 /*
175  * Attach this instance, and then all the sub-devices
176  */
177 void
178 espattach(parent, self, aux)
179 	struct device *parent, *self;
180 	void *aux;
181 {
182 	struct obio_attach_args *oa = (struct obio_attach_args *)aux;
183 	extern vaddr_t		SCSIBase;
184 	struct esp_softc	*esc = (void *)self;
185 	struct ncr53c9x_softc	*sc = &esc->sc_ncr53c9x;
186 	int			quick = 0;
187 	unsigned long		reg_offset;
188 
189 	reg_offset = SCSIBase - IOBase;
190 	esc->sc_tag = oa->oa_tag;
191 	/*
192 	 * For Wombat, Primus and Optimus motherboards, DREQ is
193 	 * visible on bit 0 of the IOSB's emulated VIA2 vIFR (and
194 	 * the scsi registers are offset 0x1000 bytes from IOBase).
195 	 *
196 	 * For the Q700/900/950 it's at f9800024 for bus 0 and
197 	 * f9800028 for bus 1 (900/950).  For these machines, that is also
198 	 * a (12-bit) configuration register for DAFB's control of the
199 	 * pseudo-DMA timing.  The default value is 0x1d1.
200 	 */
201 	esp_have_dreq = esp_dafb_have_dreq;
202 	if (sc->sc_dev.dv_unit == 0) {
203 		if (reg_offset == 0x10000) {
204 			quick = 1;
205 			esp_have_dreq = esp_iosb_have_dreq;
206 		} else if (reg_offset == 0x18000) {
207 			quick = 0;
208 		} else {
209 			if (bus_space_map(esc->sc_tag, 0xf9800024,
210 					  4, 0, &esc->sc_bsh)) {
211 				printf("failed to map 4 at 0xf9800024.\n");
212 			} else {
213 				quick = 1;
214 				bus_space_write_4(esc->sc_tag,
215 						  esc->sc_bsh, 0, 0x1d1);
216 			}
217 		}
218 	} else {
219 		if (bus_space_map(esc->sc_tag, 0xf9800028,
220 				  4, 0, &esc->sc_bsh)) {
221 			printf("failed to map 4 at 0xf9800028.\n");
222 		} else {
223 			quick = 1;
224 			bus_space_write_4(esc->sc_tag, esc->sc_bsh, 0, 0x1d1);
225 		}
226 	}
227 	if (quick) {
228 		esp_glue.gl_write_reg = esp_quick_write_reg;
229 		esp_glue.gl_dma_intr = esp_quick_dma_intr;
230 		esp_glue.gl_dma_setup = esp_quick_dma_setup;
231 		esp_glue.gl_dma_go = esp_quick_dma_go;
232 	}
233 
234 	/*
235 	 * Set up the glue for MI code early; we use some of it here.
236 	 */
237 	sc->sc_glue = &esp_glue;
238 
239 	/*
240 	 * Save the regs
241 	 */
242 	if (sc->sc_dev.dv_unit == 0) {
243 		esp0 = esc;
244 
245 		esc->sc_reg = (volatile u_char *) SCSIBase;
246 		via2_register_irq(VIA2_SCSIIRQ, esp_intr, esc);
247 		esc->irq_mask = V2IF_SCSIIRQ;
248 		if (reg_offset == 0x10000) {
249 			sc->sc_freq = 16500000;
250 		} else {
251 			sc->sc_freq = 25000000;
252 		}
253 
254 		if (esp_glue.gl_dma_go == esp_quick_dma_go) {
255 			printf(" (quick)");
256 		}
257 	} else {
258 		esp1 = esc;
259 
260 		esc->sc_reg = (volatile u_char *) SCSIBase + 0x402;
261 		via2_register_irq(VIA2_SCSIIRQ, esp_dualbus_intr, NULL);
262 		esc->irq_mask = 0;
263 		sc->sc_freq = 25000000;
264 
265 		if (esp_glue.gl_dma_go == esp_quick_dma_go) {
266 			printf(" (quick)");
267 		}
268 	}
269 
270 	printf(": address %p", esc->sc_reg);
271 
272 	sc->sc_id = 7;
273 
274 	/* gimme Mhz */
275 	sc->sc_freq /= 1000000;
276 
277 	/*
278 	 * It is necessary to try to load the 2nd config register here,
279 	 * to find out what rev the esp chip is, else the esp_reset
280 	 * will not set up the defaults correctly.
281 	 */
282 	sc->sc_cfg1 = sc->sc_id; /* | NCRCFG1_PARENB; */
283 	sc->sc_cfg2 = NCRCFG2_SCSI2;
284 	sc->sc_cfg3 = 0;
285 	sc->sc_rev = NCR_VARIANT_NCR53C96;
286 
287 	/*
288 	 * This is the value used to start sync negotiations
289 	 * Note that the NCR register "SYNCTP" is programmed
290 	 * in "clocks per byte", and has a minimum value of 4.
291 	 * The SCSI period used in negotiation is one-fourth
292 	 * of the time (in nanoseconds) needed to transfer one byte.
293 	 * Since the chip's clock is given in MHz, we have the following
294 	 * formula: 4 * period = (1000 / freq) * 4
295 	 */
296 	sc->sc_minsync = 1000 / sc->sc_freq;
297 
298 	sc->sc_minsync = 0;	/* No synchronous xfers w/o DMA */
299 	/* Really no limit, but since we want to fit into the TCR... */
300 	sc->sc_maxxfer = 8 * 1024; /*64 * 1024; XXX */
301 
302 	/*
303 	 * Configure interrupts.
304 	 */
305 	if (esc->irq_mask) {
306 		via2_reg(vPCR) = 0x22;
307 		via2_reg(vIFR) = esc->irq_mask;
308 		via2_reg(vIER) = 0x80 | esc->irq_mask;
309 	}
310 
311 	/*
312 	 * Now try to attach all the sub-devices
313 	 */
314 	ncr53c9x_attach(sc, NULL, NULL);
315 }
316 
317 /*
318  * Glue functions.
319  */
320 
321 u_char
322 esp_read_reg(sc, reg)
323 	struct ncr53c9x_softc *sc;
324 	int reg;
325 {
326 	struct esp_softc *esc = (struct esp_softc *)sc;
327 
328 	return esc->sc_reg[reg * 16];
329 }
330 
331 void
332 esp_write_reg(sc, reg, val)
333 	struct ncr53c9x_softc *sc;
334 	int reg;
335 	u_char val;
336 {
337 	struct esp_softc *esc = (struct esp_softc *)sc;
338 	u_char	v = val;
339 
340 	if (reg == NCR_CMD && v == (NCRCMD_TRANS|NCRCMD_DMA)) {
341 		v = NCRCMD_TRANS;
342 	}
343 	esc->sc_reg[reg * 16] = v;
344 }
345 
346 void
347 esp_dma_stop(sc)
348 	struct ncr53c9x_softc *sc;
349 {
350 }
351 
352 int
353 esp_dma_isactive(sc)
354 	struct ncr53c9x_softc *sc;
355 {
356 	struct esp_softc *esc = (struct esp_softc *)sc;
357 
358 	return esc->sc_active;
359 }
360 
361 int
362 esp_dma_isintr(sc)
363 	struct ncr53c9x_softc *sc;
364 {
365 	struct esp_softc *esc = (struct esp_softc *)sc;
366 
367 	return esc->sc_reg[NCR_STAT * 16] & 0x80;
368 }
369 
370 void
371 esp_dma_reset(sc)
372 	struct ncr53c9x_softc *sc;
373 {
374 	struct esp_softc *esc = (struct esp_softc *)sc;
375 
376 	esc->sc_active = 0;
377 	esc->sc_tc = 0;
378 }
379 
380 int
381 esp_dma_intr(sc)
382 	struct ncr53c9x_softc *sc;
383 {
384 	struct esp_softc *esc = (struct esp_softc *)sc;
385 	volatile u_char *cmdreg, *intrreg, *statreg, *fiforeg;
386 	u_char	*p;
387 	u_int	espphase, espstat, espintr;
388 	int	cnt, s;
389 
390 	if (esc->sc_active == 0) {
391 		printf("dma_intr--inactive DMA\n");
392 		return -1;
393 	}
394 
395 	if ((sc->sc_espintr & NCRINTR_BS) == 0) {
396 		esc->sc_active = 0;
397 		return 0;
398 	}
399 
400 	cnt = *esc->sc_dmalen;
401 	if (*esc->sc_dmalen == 0) {
402 		printf("data interrupt, but no count left.");
403 	}
404 
405 	p = *esc->sc_dmaaddr;
406 	espphase = sc->sc_phase;
407 	espstat = (u_int) sc->sc_espstat;
408 	espintr = (u_int) sc->sc_espintr;
409 	cmdreg = esc->sc_reg + NCR_CMD * 16;
410 	fiforeg = esc->sc_reg + NCR_FIFO * 16;
411 	statreg = esc->sc_reg + NCR_STAT * 16;
412 	intrreg = esc->sc_reg + NCR_INTR * 16;
413 	do {
414 		if (esc->sc_datain) {
415 			*p++ = *fiforeg;
416 			cnt--;
417 			if (espphase == DATA_IN_PHASE) {
418 				*cmdreg = NCRCMD_TRANS;
419 			} else {
420 				esc->sc_active = 0;
421 			}
422 	 	} else {
423 			if (   (espphase == DATA_OUT_PHASE)
424 			    || (espphase == MESSAGE_OUT_PHASE)) {
425 				*fiforeg = *p++;
426 				cnt--;
427 				*cmdreg = NCRCMD_TRANS;
428 			} else {
429 				esc->sc_active = 0;
430 			}
431 		}
432 
433 		if (esc->sc_active) {
434 			while (!(*statreg & 0x80));
435 			s = splhigh();
436 			espstat = *statreg;
437 			espintr = *intrreg;
438 			espphase = (espintr & NCRINTR_DIS)
439 				    ? /* Disconnected */ BUSFREE_PHASE
440 				    : espstat & PHASE_MASK;
441 			splx(s);
442 		}
443 	} while (esc->sc_active && (espintr & NCRINTR_BS));
444 	sc->sc_phase = espphase;
445 	sc->sc_espstat = (u_char) espstat;
446 	sc->sc_espintr = (u_char) espintr;
447 	*esc->sc_dmaaddr = p;
448 	*esc->sc_dmalen = cnt;
449 
450 	if (*esc->sc_dmalen == 0) {
451 		esc->sc_tc = NCRSTAT_TC;
452 	}
453 	sc->sc_espstat |= esc->sc_tc;
454 	return 0;
455 }
456 
457 int
458 esp_dma_setup(sc, addr, len, datain, dmasize)
459 	struct ncr53c9x_softc *sc;
460 	caddr_t *addr;
461 	size_t *len;
462 	int datain;
463 	size_t *dmasize;
464 {
465 	struct esp_softc *esc = (struct esp_softc *)sc;
466 
467 	esc->sc_dmaaddr = addr;
468 	esc->sc_dmalen = len;
469 	esc->sc_datain = datain;
470 	esc->sc_dmasize = *dmasize;
471 	esc->sc_tc = 0;
472 
473 	return 0;
474 }
475 
476 void
477 esp_dma_go(sc)
478 	struct ncr53c9x_softc *sc;
479 {
480 	struct esp_softc *esc = (struct esp_softc *)sc;
481 
482 	if (esc->sc_datain == 0) {
483 		esc->sc_reg[NCR_FIFO * 16] = **esc->sc_dmaaddr;
484 		(*esc->sc_dmalen)--;
485 		(*esc->sc_dmaaddr)++;
486 	}
487 	esc->sc_active = 1;
488 }
489 
490 void
491 esp_quick_write_reg(sc, reg, val)
492 	struct ncr53c9x_softc *sc;
493 	int reg;
494 	u_char val;
495 {
496 	struct esp_softc *esc = (struct esp_softc *)sc;
497 
498 	esc->sc_reg[reg * 16] = val;
499 }
500 
501 int
502 esp_quick_dma_intr(sc)
503 	struct ncr53c9x_softc *sc;
504 {
505 	struct esp_softc *esc = (struct esp_softc *)sc;
506 	int trans=0, resid=0;
507 
508 	if (esc->sc_active == 0)
509 		panic("dma_intr--inactive DMA\n");
510 
511 	esc->sc_active = 0;
512 
513 	if (esc->sc_dmasize == 0) {
514 		int	res;
515 
516 		res = 65536;
517 		res -= NCR_READ_REG(sc, NCR_TCL);
518 		res -= NCR_READ_REG(sc, NCR_TCM) << 8;
519 		printf("dmaintr: discarded %d b (last transfer was %d b).\n",
520 			res, esc->sc_prevdmasize);
521 		return 0;
522 	}
523 
524 	if (esc->sc_datain &&
525 	    (resid = (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
526 		printf("dmaintr: empty FIFO of %d\n", resid);
527 		DELAY(1);
528 	}
529 
530 	if ((sc->sc_espstat & NCRSTAT_TC) == 0) {
531 		resid += NCR_READ_REG(sc, NCR_TCL);
532 		resid += NCR_READ_REG(sc, NCR_TCM) << 8;
533 
534 		if (resid == 0)
535 			resid = 65536;
536 	}
537 
538 	trans = esc->sc_dmasize - resid;
539 	if (trans < 0) {
540 		printf("dmaintr: trans < 0????");
541 		trans = esc->sc_dmasize;
542 	}
543 
544 	NCR_DMA(("dmaintr: trans %d, resid %d.\n", trans, resid));
545 	*esc->sc_dmaaddr += trans;
546 	*esc->sc_dmalen -= trans;
547 
548 	return 0;
549 }
550 
551 int
552 esp_quick_dma_setup(sc, addr, len, datain, dmasize)
553 	struct ncr53c9x_softc *sc;
554 	caddr_t *addr;
555 	size_t *len;
556 	int datain;
557 	size_t *dmasize;
558 {
559 	struct esp_softc *esc = (struct esp_softc *)sc;
560 
561 	esc->sc_dmaaddr = addr;
562 	esc->sc_dmalen = len;
563 
564 	esc->sc_pdmaddr = (u_int16_t *) *addr;
565 	esc->sc_pdmalen = *len;
566 	if (esc->sc_pdmalen & 1) {
567 		esc->sc_pdmalen--;
568 		esc->sc_pad = 1;
569 	} else {
570 		esc->sc_pad = 0;
571 	}
572 
573 	esc->sc_datain = datain;
574 	esc->sc_prevdmasize = esc->sc_dmasize;
575 	esc->sc_dmasize = *dmasize;
576 
577 	return 0;
578 }
579 
580 static __inline__ int
581 esp_dafb_have_dreq(esc)
582 	struct esp_softc *esc;
583 {
584 	u_int32_t r;
585 
586 	r = bus_space_read_4(esc->sc_tag, esc->sc_bsh, 0);
587 	return (r & 0x200);
588 }
589 
590 static __inline__ int
591 esp_iosb_have_dreq(esc)
592 	struct esp_softc *esc;
593 {
594 	return (via2_reg(vIFR) & V2IF_SCSIDRQ);
595 }
596 
597 static int espspl=-1;
598 #define __splx(s) __asm __volatile ("movew %0,sr" : : "di" (s));
599 #define __spl2()  __splx(PSL_S|PSL_IPL2)
600 #define __spl6()  __splx(PSL_S|PSL_IPL6)
601 
602 void
603 esp_quick_dma_go(sc)
604 	struct ncr53c9x_softc *sc;
605 {
606 	struct esp_softc *esc = (struct esp_softc *)sc;
607 	extern int *nofault;
608 	label_t faultbuf;
609 	u_int16_t volatile *pdma;
610 	u_char volatile *statreg;
611 
612 	esc->sc_active = 1;
613 
614 	espspl = spl2();
615 
616 restart_dmago:
617 	nofault = (int *) &faultbuf;
618 	if (setjmp((label_t *) nofault)) {
619 		int	i=0;
620 
621 		nofault = (int *) 0;
622 		statreg = esc->sc_reg + NCR_STAT * 16;
623 		for (;;) {
624 			if (*statreg & 0x80) {
625 				goto gotintr;
626 			}
627 
628 			if (esp_have_dreq(esc)) {
629 				break;
630 			}
631 
632 			DELAY(1);
633 			if (i++ > 10000)
634 				panic("esp_dma_go: Argh!");
635 		}
636 		goto restart_dmago;
637 	}
638 
639 	statreg = esc->sc_reg + NCR_STAT * 16;
640 	pdma = (u_int16_t *) (esc->sc_reg + 0x100);
641 
642 #define WAIT while (!esp_have_dreq(esc)) if (*statreg & 0x80) goto gotintr
643 
644 	if (esc->sc_datain == 0) {
645 		while (esc->sc_pdmalen) {
646 			WAIT;
647 			__spl6(); *pdma = *(esc->sc_pdmaddr)++; __spl2()
648 			esc->sc_pdmalen -= 2;
649 		}
650 		if (esc->sc_pad) {
651 			unsigned short	us;
652 			unsigned char	*c;
653 			c = (unsigned char *) esc->sc_pdmaddr;
654 			us = *c;
655 			WAIT;
656 			__spl6(); *pdma = us; __spl2()
657 		}
658 	} else {
659 		while (esc->sc_pdmalen) {
660 			WAIT;
661 			__spl6(); *(esc->sc_pdmaddr)++ = *pdma; __spl2()
662 			esc->sc_pdmalen -= 2;
663 		}
664 		if (esc->sc_pad) {
665 			unsigned short	us;
666 			unsigned char	*c;
667 			WAIT;
668 			__spl6(); us = *pdma; __spl2()
669 			c = (unsigned char *) esc->sc_pdmaddr;
670 			*c = us & 0xff;
671 		}
672 	}
673 #undef WAIT
674 
675 	nofault = (int *) 0;
676 
677 	if ((*statreg & 0x80) == 0) {
678 		if (espspl != -1) splx(espspl); espspl = -1;
679 		return;
680 	}
681 
682 gotintr:
683 	ncr53c9x_intr(sc);
684 	if (espspl != -1) splx(espspl); espspl = -1;
685 }
686 
687 void
688 esp_intr(sc)
689 	void *sc;
690 {
691 	struct esp_softc *esc = (struct esp_softc *)sc;
692 	int	i = 0;
693 
694 	do {
695 		if (esc->sc_reg[NCR_STAT * 16] & 0x80) {
696 			ncr53c9x_intr((struct ncr53c9x_softc *) esp0);
697 			i++;
698 		}
699 
700 		if (!i) {
701 			delay(10000);
702 		}
703 	} while (!i++);
704 }
705 
706 void
707 esp_dualbus_intr(sc)
708 	void *sc;
709 {
710 	int	i = 0;
711 
712 	do {
713 		if (esp0 && (esp0->sc_reg[NCR_STAT * 16] & 0x80)) {
714 			ncr53c9x_intr((struct ncr53c9x_softc *) esp0);
715 			i++;
716 		}
717 
718 		if (esp1 && (esp1->sc_reg[NCR_STAT * 16] & 0x80)) {
719 			ncr53c9x_intr((struct ncr53c9x_softc *) esp1);
720 			i++;
721 		}
722 
723 		if (!i) {
724 			delay(10000);
725 		}
726 	} while (!i++);
727 }
728