xref: /netbsd-src/sys/dev/tc/tcds.c (revision 27578b9aac214cc7796ead81dcc5427e79d5f2a0)
1 /* $NetBSD: tcds.c,v 1.2 2001/08/22 05:00:27 nisimura Exp $ */
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center.
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 the NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
42  * All rights reserved.
43  *
44  * Author: Keith Bostic, Chris G. Demetriou
45  *
46  * Permission to use, copy, modify and distribute this software and
47  * its documentation is hereby granted, provided that both the copyright
48  * notice and this permission notice appear in all copies of the
49  * software, derivative works or modified versions, and any portions
50  * thereof, and that both notices appear in supporting documentation.
51  *
52  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
53  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
54  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
55  *
56  * Carnegie Mellon requests users of this software to return to
57  *
58  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
59  *  School of Computer Science
60  *  Carnegie Mellon University
61  *  Pittsburgh PA 15213-3890
62  *
63  * any improvements or extensions that they make and grant Carnegie the
64  * rights to redistribute these changes.
65  */
66 
67 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
68 
69 __KERNEL_RCSID(0, "$NetBSD: tcds.c,v 1.2 2001/08/22 05:00:27 nisimura Exp $");
70 
71 #include <sys/param.h>
72 #include <sys/kernel.h>
73 #include <sys/systm.h>
74 #include <sys/device.h>
75 #include <sys/malloc.h>
76 
77 #ifdef __alpha__
78 #include <machine/rpb.h>
79 #endif /* __alpha__ */
80 
81 #include <dev/scsipi/scsi_all.h>
82 #include <dev/scsipi/scsipi_all.h>
83 #include <dev/scsipi/scsiconf.h>
84 
85 #include <dev/ic/ncr53c9xvar.h>
86 
87 #include <machine/bus.h>
88 
89 #include <dev/tc/tcvar.h>
90 #include <dev/tc/tcdsreg.h>
91 #include <dev/tc/tcdsvar.h>
92 
93 #include "locators.h"
94 
95 struct tcds_softc {
96 	struct	device sc_dv;
97 	bus_space_tag_t sc_bst;
98 	bus_space_handle_t sc_bsh;
99 	bus_dma_tag_t sc_dmat;
100 	void	*sc_cookie;
101 	int	sc_flags;
102 	struct tcds_slotconfig sc_slots[2];
103 };
104 
105 /* sc_flags */
106 #define	TCDSF_BASEBOARD		0x01	/* baseboard on DEC 3000 */
107 #define	TCDSF_FASTSCSI		0x02	/* supports Fast SCSI */
108 
109 /* Definition of the driver for autoconfig. */
110 int	tcdsmatch __P((struct device *, struct cfdata *, void *));
111 void	tcdsattach __P((struct device *, struct device *, void *));
112 int     tcdsprint __P((void *, const char *));
113 int	tcdssubmatch __P((struct device *, struct cfdata *, void *));
114 
115 struct cfattach tcds_ca = {
116 	sizeof(struct tcds_softc), tcdsmatch, tcdsattach,
117 };
118 
119 /*static*/ int	tcds_intr __P((void *));
120 /*static*/ int	tcds_intrnull __P((void *));
121 
122 struct tcds_device {
123 	const char *td_name;
124 	int td_flags;
125 } tcds_devices[] = {
126 #ifdef __alpha__
127 	{ "PMAZ-DS ",	TCDSF_BASEBOARD },
128 	{ "PMAZ-FS ",	TCDSF_BASEBOARD|TCDSF_FASTSCSI },
129 #endif /* __alpha__ */
130 	{ "PMAZB-AA",	0 },
131 	{ "PMAZC-AA",	TCDSF_FASTSCSI },
132 	{ NULL,		0 },
133 };
134 
135 struct tcds_device *tcds_lookup __P((const char *));
136 void	tcds_params __P((struct tcds_softc *, int, int *, int *));
137 
138 struct tcds_device *
139 tcds_lookup(modname)
140 	const char *modname;
141 {
142 	struct tcds_device *td;
143 
144 	for (td = tcds_devices; td->td_name != NULL; td++)
145 		if (strncmp(td->td_name, modname, TC_ROM_LLEN) == 0)
146 			return (td);
147 
148 	return (NULL);
149 }
150 
151 int
152 tcdsmatch(parent, cfdata, aux)
153 	struct device *parent;
154 	struct cfdata *cfdata;
155 	void *aux;
156 {
157 	struct tc_attach_args *ta = aux;
158 
159 	return (tcds_lookup(ta->ta_modname) != NULL);
160 }
161 
162 void
163 tcdsattach(parent, self, aux)
164 	struct device *parent, *self;
165 	void *aux;
166 {
167 	struct tcds_softc *sc = (struct tcds_softc *)self;
168 	struct tc_attach_args *ta = aux;
169 	struct tcdsdev_attach_args tcdsdev;
170 	struct tcds_slotconfig *slotc;
171 	struct tcds_device *td;
172 	bus_space_handle_t sbsh[2];
173 	int i, gpi2;
174 	const struct evcnt *pevcnt;
175 
176 	td = tcds_lookup(ta->ta_modname);
177 	if (td == NULL)
178 		panic("\ntcdsattach: impossible");
179 
180 	printf(": TurboChannel Dual SCSI");
181 	if (td->td_flags & TCDSF_BASEBOARD)
182 		printf(" (baseboard)");
183 	printf("\n");
184 
185 	sc->sc_flags = td->td_flags;
186 
187 	sc->sc_bst = ta->ta_memt;
188 	sc->sc_dmat = ta->ta_dmat;
189 
190 	/*
191 	 * Map the device.
192 	 */
193 	if (bus_space_map(sc->sc_bst, ta->ta_addr,
194 	    (TCDS_SCSI1_OFFSET + 0x100), 0, &sc->sc_bsh)) {
195 		printf("%s: unable to map device\n", sc->sc_dv.dv_xname);
196 		return;
197 	}
198 
199 	/*
200 	 * Now, slice off two subregions for the individual NCR SCSI chips.
201 	 */
202 	if (bus_space_subregion(sc->sc_bst, sc->sc_bsh, TCDS_SCSI0_OFFSET,
203 	    0x100, &sbsh[0]) ||
204 	    bus_space_subregion(sc->sc_bst, sc->sc_bsh, TCDS_SCSI1_OFFSET,
205 	    0x100, &sbsh[1])) {
206 		printf("%s: unable to subregion SCSI chip space\n",
207 		    sc->sc_dv.dv_xname);
208 		return;
209 	}
210 
211 	sc->sc_cookie = ta->ta_cookie;
212 
213 	pevcnt = tc_intr_evcnt(parent, sc->sc_cookie);
214 	tc_intr_establish(parent, sc->sc_cookie, TC_IPL_BIO, tcds_intr, sc);
215 
216 	/*
217 	 * XXX
218 	 * IMER apparently has some random (or, not so random, but still
219 	 * not useful) bits set in it when the system boots.  Clear it.
220 	 */
221 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_IMER, 0);
222 
223 	/* XXX Initial contents of CIR? */
224 
225 	/*
226 	 * Remember if GPI2 is set in the CIR; we'll need it later.
227 	 */
228 	gpi2 = (bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR) &
229 	    TCDS_CIR_GPI_2) != 0;
230 
231 	/*
232 	 * Set up the per-slot defintions for later use.
233 	 */
234 
235 	/* fill in common information first */
236 	for (i = 0; i < 2; i++) {
237 		char *cp;
238 
239 		slotc = &sc->sc_slots[i];
240 		bzero(slotc, sizeof *slotc);	/* clear everything */
241 
242 		cp = slotc->sc_name;
243 		snprintf(cp, sizeof(slotc->sc_name), "chip %d", i);
244 		evcnt_attach_dynamic(&slotc->sc_evcnt, EVCNT_TYPE_INTR,
245 		    pevcnt, sc->sc_dv.dv_xname, cp);
246 
247 		slotc->sc_slot = i;
248 		slotc->sc_bst = sc->sc_bst;
249 		slotc->sc_bsh = sc->sc_bsh;
250 		slotc->sc_intrhand = tcds_intrnull;
251 		slotc->sc_intrarg = (void *)(long)i;
252 	}
253 
254 	/* information for slot 0 */
255 	slotc = &sc->sc_slots[0];
256 	slotc->sc_resetbits = TCDS_CIR_SCSI0_RESET;
257 	slotc->sc_intrmaskbits =
258 	    TCDS_IMER_SCSI0_MASK | TCDS_IMER_SCSI0_ENB;
259 	slotc->sc_intrbits = TCDS_CIR_SCSI0_INT;
260 	slotc->sc_dmabits = TCDS_CIR_SCSI0_DMAENA;
261 	slotc->sc_errorbits = 0;				/* XXX */
262 	slotc->sc_sda = TCDS_SCSI0_DMA_ADDR;
263 	slotc->sc_dic = TCDS_SCSI0_DMA_INTR;
264 	slotc->sc_dud0 = TCDS_SCSI0_DMA_DUD0;
265 	slotc->sc_dud1 = TCDS_SCSI0_DMA_DUD1;
266 
267 	/* information for slot 1 */
268 	slotc = &sc->sc_slots[1];
269 	slotc->sc_resetbits = TCDS_CIR_SCSI1_RESET;
270 	slotc->sc_intrmaskbits =
271 	    TCDS_IMER_SCSI1_MASK | TCDS_IMER_SCSI1_ENB;
272 	slotc->sc_intrbits = TCDS_CIR_SCSI1_INT;
273 	slotc->sc_dmabits = TCDS_CIR_SCSI1_DMAENA;
274 	slotc->sc_errorbits = 0;				/* XXX */
275 	slotc->sc_sda = TCDS_SCSI1_DMA_ADDR;
276 	slotc->sc_dic = TCDS_SCSI1_DMA_INTR;
277 	slotc->sc_dud0 = TCDS_SCSI1_DMA_DUD0;
278 	slotc->sc_dud1 = TCDS_SCSI1_DMA_DUD1;
279 
280 	/* find the hardware attached to the TCDS ASIC */
281 	for (i = 0; i < 2; i++) {
282 		tcds_params(sc, i, &tcdsdev.tcdsda_id,
283 		    &tcdsdev.tcdsda_fast);
284 
285 		tcdsdev.tcdsda_bst = sc->sc_bst;
286 		tcdsdev.tcdsda_bsh = sbsh[i];
287 		tcdsdev.tcdsda_dmat = sc->sc_dmat;
288 		tcdsdev.tcdsda_chip = i;
289 		tcdsdev.tcdsda_sc = &sc->sc_slots[i];
290 		/*
291 		 * Determine the chip frequency.  TCDSF_FASTSCSI will be set
292 		 * for TC option cards.  For baseboard chips, GPI2 is set, for a
293 		 * 25MHz clock, else a 40MHz clock.
294 		 */
295 		if ((sc->sc_flags & TCDSF_BASEBOARD && gpi2 == 0) ||
296 		    sc->sc_flags & TCDSF_FASTSCSI) {
297 			tcdsdev.tcdsda_freq = 40000000;
298 			tcdsdev.tcdsda_period = tcdsdev.tcdsda_fast ? 4 : 8;
299 		} else {
300 			tcdsdev.tcdsda_freq = 25000000;
301 			tcdsdev.tcdsda_period = 5;
302 		}
303 		if (sc->sc_flags & TCDSF_BASEBOARD)
304 			tcdsdev.tcdsda_variant = NCR_VARIANT_NCR53C94;
305 		else
306 			tcdsdev.tcdsda_variant = NCR_VARIANT_NCR53C96;
307 
308 		tcds_scsi_reset(tcdsdev.tcdsda_sc);
309 
310 		config_found_sm(self, &tcdsdev, tcdsprint, tcdssubmatch);
311 #ifdef __alpha__
312 		/*
313 		 * The second SCSI chip isn't present on the baseboard TCDS
314 		 * on the DEC Alpha 3000/300 series.
315 		 */
316 		if (sc->sc_flags & TCDSF_BASEBOARD &&
317 		    cputype == ST_DEC_3000_300)
318 			break;
319 #endif /* __alpha__ */
320 	}
321 }
322 
323 int
324 tcdssubmatch(parent, cf, aux)
325 	struct device *parent;
326 	struct cfdata *cf;
327 	void *aux;
328 {
329 	struct tcdsdev_attach_args *tcdsdev = aux;
330 
331 	if (cf->cf_loc[TCDSCF_CHIP] != TCDSCF_CHIP_DEFAULT &&
332 	    cf->cf_loc[TCDSCF_CHIP] != tcdsdev->tcdsda_chip)
333 		return (0);
334 
335 	return ((*cf->cf_attach->ca_match)(parent, cf, aux));
336 }
337 
338 int
339 tcdsprint(aux, pnp)
340 	void *aux;
341 	const char *pnp;
342 {
343 	struct tcdsdev_attach_args *tcdsdev = aux;
344 
345 	/* Only ASCs can attach to TCDSs; easy. */
346 	if (pnp)
347 		printf("asc at %s", pnp);
348 
349 	printf(" chip %d", tcdsdev->tcdsda_chip);
350 
351 	return (UNCONF);
352 }
353 
354 void
355 tcds_intr_establish(tcds, slot, func, arg)
356 	struct device *tcds;
357 	int slot;
358 	int (*func) __P((void *));
359 	void *arg;
360 {
361 	struct tcds_softc *sc = (struct tcds_softc *)tcds;
362 
363 	if (sc->sc_slots[slot].sc_intrhand != tcds_intrnull)
364 		panic("tcds_intr_establish: chip %d twice", slot);
365 
366 	sc->sc_slots[slot].sc_intrhand = func;
367 	sc->sc_slots[slot].sc_intrarg = arg;
368 	tcds_scsi_reset(&sc->sc_slots[slot]);
369 }
370 
371 void
372 tcds_intr_disestablish(tcds, slot)
373 	struct device *tcds;
374 	int slot;
375 {
376 	struct tcds_softc *sc = (struct tcds_softc *)tcds;
377 
378 	if (sc->sc_slots[slot].sc_intrhand == tcds_intrnull)
379 		panic("tcds_intr_disestablish: chip %d missing intr",
380 		    slot);
381 
382 	sc->sc_slots[slot].sc_intrhand = tcds_intrnull;
383 	sc->sc_slots[slot].sc_intrarg = (void *)(u_long)slot;
384 
385 	tcds_dma_enable(&sc->sc_slots[slot], 0);
386 	tcds_scsi_enable(&sc->sc_slots[slot], 0);
387 }
388 
389 int
390 tcds_intrnull(val)
391 	void *val;
392 {
393 
394 	panic("tcds_intrnull: uncaught TCDS intr for chip %lu\n",
395 	    (u_long)val);
396 }
397 
398 void
399 tcds_scsi_reset(sc)
400 	struct tcds_slotconfig *sc;
401 {
402 	u_int32_t cir;
403 
404 	tcds_dma_enable(sc, 0);
405 	tcds_scsi_enable(sc, 0);
406 
407 	cir = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
408 	TCDS_CIR_CLR(cir, sc->sc_resetbits);
409 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR, cir);
410 
411 	DELAY(1);
412 
413 	cir = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
414 	TCDS_CIR_SET(cir, sc->sc_resetbits);
415 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR, cir);
416 
417 	tcds_scsi_enable(sc, 1);
418 	tcds_dma_enable(sc, 1);
419 }
420 
421 void
422 tcds_scsi_enable(sc, on)
423 	struct tcds_slotconfig *sc;
424 	int on;
425 {
426 	u_int32_t imer;
427 
428 	imer = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_IMER);
429 
430 	if (on)
431 		imer |= sc->sc_intrmaskbits;
432 	else
433 		imer &= ~sc->sc_intrmaskbits;
434 
435 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_IMER, imer);
436 }
437 
438 void
439 tcds_dma_enable(sc, on)
440 	struct tcds_slotconfig *sc;
441 	int on;
442 {
443 	u_int32_t cir;
444 
445 	cir = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
446 
447 	/* XXX Clear/set IOSLOT/PBS bits. */
448 	if (on)
449 		TCDS_CIR_SET(cir, sc->sc_dmabits);
450 	else
451 		TCDS_CIR_CLR(cir, sc->sc_dmabits);
452 
453 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR, cir);
454 }
455 
456 int
457 tcds_scsi_isintr(sc, clear)
458 	struct tcds_slotconfig *sc;
459 	int clear;
460 {
461 	u_int32_t cir;
462 
463 	cir = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
464 
465 	if ((cir & sc->sc_intrbits) != 0) {
466 		if (clear) {
467 			TCDS_CIR_CLR(cir, sc->sc_intrbits);
468 			bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR,
469 			    cir);
470 		}
471 		return (1);
472 	} else
473 		return (0);
474 }
475 
476 int
477 tcds_scsi_iserr(sc)
478 	struct tcds_slotconfig *sc;
479 {
480 	u_int32_t cir;
481 
482 	cir = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
483 	return ((cir & sc->sc_errorbits) != 0);
484 }
485 
486 int
487 tcds_intr(arg)
488 	void *arg;
489 {
490 	struct tcds_softc *sc = arg;
491 	u_int32_t ir, ir0;
492 
493 	/*
494 	 * XXX
495 	 * Copy and clear (gag!) the interrupts.
496 	 */
497 	ir = ir0 = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR);
498 	TCDS_CIR_CLR(ir0, TCDS_CIR_ALLINTR);
499 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, TCDS_CIR, ir0);
500 	tc_syncbus();
501 
502 #define	INCRINTRCNT(slot)	sc->sc_slots[slot].sc_evcnt.ev_count++
503 
504 #define	CHECKINTR(slot)							\
505 	if (ir & sc->sc_slots[slot].sc_intrbits) {			\
506 		INCRINTRCNT(slot);					\
507 		(void)(*sc->sc_slots[slot].sc_intrhand)			\
508 		    (sc->sc_slots[slot].sc_intrarg);			\
509 	}
510 	CHECKINTR(0);
511 	CHECKINTR(1);
512 #undef CHECKINTR
513 
514 #ifdef DIAGNOSTIC
515 	/*
516 	 * Interrupts not currently handled, but would like to know if they
517 	 * occur.
518 	 *
519 	 * XXX
520 	 * Don't know if we have to set the interrupt mask and enable bits
521 	 * in the IMER to allow some of them to happen?
522 	 */
523 #define	PRINTINTR(msg, bits)						\
524 	if (ir & bits)							\
525 		printf("%s: %s", sc->sc_dv.dv_xname, msg);
526 	PRINTINTR("SCSI0 DREQ interrupt.\n", TCDS_CIR_SCSI0_DREQ);
527 	PRINTINTR("SCSI1 DREQ interrupt.\n", TCDS_CIR_SCSI1_DREQ);
528 	PRINTINTR("SCSI0 prefetch interrupt.\n", TCDS_CIR_SCSI0_PREFETCH);
529 	PRINTINTR("SCSI1 prefetch interrupt.\n", TCDS_CIR_SCSI1_PREFETCH);
530 	PRINTINTR("SCSI0 DMA error.\n", TCDS_CIR_SCSI0_DMA);
531 	PRINTINTR("SCSI1 DMA error.\n", TCDS_CIR_SCSI1_DMA);
532 	PRINTINTR("SCSI0 DB parity error.\n", TCDS_CIR_SCSI0_DB);
533 	PRINTINTR("SCSI1 DB parity error.\n", TCDS_CIR_SCSI1_DB);
534 	PRINTINTR("SCSI0 DMA buffer parity error.\n", TCDS_CIR_SCSI0_DMAB_PAR);
535 	PRINTINTR("SCSI1 DMA buffer parity error.\n", TCDS_CIR_SCSI1_DMAB_PAR);
536 	PRINTINTR("SCSI0 DMA read parity error.\n", TCDS_CIR_SCSI0_DMAR_PAR);
537 	PRINTINTR("SCSI1 DMA read parity error.\n", TCDS_CIR_SCSI1_DMAR_PAR);
538 	PRINTINTR("TC write parity error.\n", TCDS_CIR_TCIOW_PAR);
539 	PRINTINTR("TC I/O address parity error.\n", TCDS_CIR_TCIOA_PAR);
540 #undef PRINTINTR
541 #endif
542 
543 	/*
544 	 * XXX
545 	 * The MACH source had this, with the comment:
546 	 *	This is wrong, but machine keeps dying.
547 	 */
548 	DELAY(1);
549 
550 	return (1);
551 }
552 
553 void
554 tcds_params(sc, chip, idp, fastp)
555 	struct tcds_softc *sc;
556 	int chip, *idp, *fastp;
557 {
558 	int id, fast;
559 	u_int32_t ids;
560 
561 #ifdef __alpha__
562 	if (sc->sc_flags & TCDSF_BASEBOARD) {
563 		extern u_int8_t dec_3000_scsiid[], dec_3000_scsifast[];
564 
565 		id = dec_3000_scsiid[chip];
566 		fast = dec_3000_scsifast[chip];
567 	} else
568 #endif /* __alpha__ */
569 	{
570 		/*
571 		 * SCSI IDs are stored in the EEPROM, along with whether or
572 		 * not the device is "fast".  Chip 0 is the high nibble,
573 		 * chip 1 the low nibble.
574 		 */
575 		ids = bus_space_read_4(sc->sc_bst, sc->sc_bsh, TCDS_EEPROM_IDS);
576 		if (chip == 0)
577 			ids >>= 4;
578 
579 		id = ids & 0x7;
580 		fast = ids & 0x8;
581 	}
582 
583 	if (id < 0 || id > 7) {
584 		printf("%s: WARNING: bad SCSI ID %d for chip %d, using 7\n",
585 		    sc->sc_dv.dv_xname, id, chip);
586 		id = 7;
587 	}
588 
589 	if (fast)
590 		printf("%s: fast mode set for chip %d\n",
591 		    sc->sc_dv.dv_xname, chip);
592 
593 	*idp = id;
594 	*fastp = fast;
595 }
596