xref: /netbsd-src/sys/dev/pci/ahd_pci.c (revision da5f4674a3fc214be3572d358b66af40ab9401e7)
1 /*	$NetBSD: ahd_pci.c,v 1.6 2003/08/29 04:17:39 thorpej Exp $	*/
2 
3 /*
4  * Product specific probe and attach routines for:
5  *	aic7901 and aic7902 SCSI controllers
6  *
7  * Copyright (c) 1994-2001 Justin T. Gibbs.
8  * Copyright (c) 2000-2002 Adaptec Inc.
9  * All rights reserved.
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  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  *
43  * Id: //depot/aic7xxx/aic7xxx/aic79xx_pci.c#76 $
44  *
45  * $FreeBSD: src/sys/dev/aic7xxx/aic79xx_pci.c,v 1.14 2003/06/28 04:39:49 gibbs Exp $
46  */
47 /*
48  * Ported from FreeBSD by Pascal Renauld, Network Storage Solutions, Inc. - April 2003
49  */
50 
51 #include <sys/cdefs.h>
52 __KERNEL_RCSID(0, "$NetBSD: ahd_pci.c,v 1.6 2003/08/29 04:17:39 thorpej Exp $");
53 
54 #define AHD_PCI_IOADDR	PCI_MAPREG_START	/* I/O Address */
55 #define AHD_PCI_MEMADDR	(PCI_MAPREG_START + 4)	/* Mem I/O Address */
56 
57 #include <dev/ic/aic79xx_osm.h>
58 #include <dev/ic/aic79xx_inline.h>
59 
60 static __inline uint64_t
61 ahd_compose_id(u_int device, u_int vendor, u_int subdevice, u_int subvendor)
62 {
63 	uint64_t id;
64 
65 	id = subvendor
66 	   | (subdevice << 16)
67 	   | ((uint64_t)vendor << 32)
68 	   | ((uint64_t)device << 48);
69 
70 	return (id);
71 }
72 
73 #define ID_ALL_MASK			0xFFFFFFFFFFFFFFFFull
74 #define ID_ALL_IROC_MASK		0xFFFFFF7FFFFFFFFFull
75 #define ID_DEV_VENDOR_MASK		0xFFFFFFFF00000000ull
76 #define ID_9005_GENERIC_MASK		0xFFF0FFFF00000000ull
77 #define ID_9005_GENERIC_IROC_MASK	0xFFF0FF7F00000000ull
78 
79 #define ID_AIC7901			0x800F9005FFFF9005ull
80 #define ID_AHA_29320A			0x8000900500609005ull
81 #define ID_AHA_29320ALP			0x8017900500449005ull
82 
83 #define ID_AIC7901A			0x801E9005FFFF9005ull
84 #define ID_AHA_29320			0x8012900500429005ull
85 #define ID_AHA_29320B			0x8013900500439005ull
86 #define ID_AHA_29320LP			0x8014900500449005ull
87 
88 #define ID_AIC7902			0x801F9005FFFF9005ull
89 #define ID_AIC7902_B			0x801D9005FFFF9005ull
90 #define ID_AHA_39320			0x8010900500409005ull
91 #define ID_AHA_39320_B			0x8015900500409005ull
92 #define ID_AHA_39320A			0x8016900500409005ull
93 #define ID_AHA_39320D			0x8011900500419005ull
94 #define ID_AHA_39320D_B			0x801C900500419005ull
95 #define ID_AHA_39320D_HP		0x8011900500AC0E11ull
96 #define ID_AHA_39320D_B_HP		0x801C900500AC0E11ull
97 #define ID_AIC7902_PCI_REV_A4		0x3
98 #define ID_AIC7902_PCI_REV_B0		0x10
99 #define SUBID_HP			0x0E11
100 
101 #define DEVID_9005_TYPE(id) ((id) & 0xF)
102 #define		DEVID_9005_TYPE_HBA		0x0	/* Standard Card */
103 #define		DEVID_9005_TYPE_HBA_2EXT	0x1	/* 2 External Ports */
104 #define		DEVID_9005_TYPE_IROC		0x8	/* Raid(0,1,10) Card */
105 #define		DEVID_9005_TYPE_MB		0xF	/* On Motherboard */
106 
107 #define DEVID_9005_MFUNC(id) ((id) & 0x10)
108 
109 #define DEVID_9005_PACKETIZED(id) ((id) & 0x8000)
110 
111 #define SUBID_9005_TYPE(id) ((id) & 0xF)
112 #define		SUBID_9005_TYPE_HBA		0x0	/* Standard Card */
113 #define		SUBID_9005_TYPE_MB		0xF	/* On Motherboard */
114 
115 #define SUBID_9005_AUTOTERM(id)	(((id) & 0x10) == 0)
116 
117 #define SUBID_9005_LEGACYCONN_FUNC(id) ((id) & 0x20)
118 
119 #define SUBID_9005_SEEPTYPE(id) ((id) & 0x0C0) >> 6)
120 #define		SUBID_9005_SEEPTYPE_NONE	0x0
121 #define		SUBID_9005_SEEPTYPE_4K		0x1
122 
123 static ahd_device_setup_t ahd_aic7901_setup;
124 static ahd_device_setup_t ahd_aic7901A_setup;
125 static ahd_device_setup_t ahd_aic7902_setup;
126 static ahd_device_setup_t ahd_aic790X_setup;
127 
128 struct ahd_pci_identity ahd_pci_ident_table [] =
129 {
130 	/* aic7901 based controllers */
131 	{
132 		ID_AHA_29320A,
133 		ID_ALL_MASK,
134 		"Adaptec 29320A Ultra320 SCSI adapter",
135 		ahd_aic7901_setup
136 	},
137 	{
138 		ID_AHA_29320ALP,
139 		ID_ALL_MASK,
140 		"Adaptec 29320ALP Ultra320 SCSI adapter",
141 		ahd_aic7901_setup
142 	},
143 	/* aic7901A based controllers */
144 	{
145 		ID_AHA_29320,
146 		ID_ALL_MASK,
147 		"Adaptec 29320 Ultra320 SCSI adapter",
148 		ahd_aic7901A_setup
149 	},
150 	{
151 		ID_AHA_29320B,
152 		ID_ALL_MASK,
153 		"Adaptec 29320B Ultra320 SCSI adapter",
154 		ahd_aic7901A_setup
155 	},
156 	{
157 		ID_AHA_29320LP,
158 		ID_ALL_MASK,
159 		"Adaptec 29320LP Ultra320 SCSI adapter",
160 		ahd_aic7901A_setup
161 	},
162 	/* aic7902 based controllers */
163 	{
164 		ID_AHA_39320,
165 		ID_ALL_MASK,
166 		"Adaptec 39320 Ultra320 SCSI adapter",
167 		ahd_aic7902_setup
168 	},
169 	{
170 		ID_AHA_39320_B,
171 		ID_ALL_MASK,
172 		"Adaptec 39320 Ultra320 SCSI adapter",
173 		ahd_aic7902_setup
174 	},
175 	{
176 		ID_AHA_39320A,
177 		ID_ALL_MASK,
178 		"Adaptec 39320A Ultra320 SCSI adapter",
179 		ahd_aic7902_setup
180 	},
181 	{
182 		ID_AHA_39320D,
183 		ID_ALL_MASK,
184 		"Adaptec 39320D Ultra320 SCSI adapter",
185 		ahd_aic7902_setup
186 	},
187 	{
188 		ID_AHA_39320D_HP,
189 		ID_ALL_MASK,
190 		"Adaptec (HP OEM) 39320D Ultra320 SCSI adapter",
191 		ahd_aic7902_setup
192 	},
193 	{
194 		ID_AHA_39320D_B,
195 		ID_ALL_MASK,
196 		"Adaptec 39320D Ultra320 SCSI adapter",
197 		ahd_aic7902_setup
198 	},
199 	{
200 		ID_AHA_39320D_B_HP,
201 		ID_ALL_MASK,
202 		"Adaptec (HP OEM) 39320D Ultra320 SCSI adapter",
203 		ahd_aic7902_setup
204 	},
205 	{
206 		ID_AHA_29320,
207 		ID_ALL_MASK,
208 		"Adaptec 29320 Ultra320 SCSI adapter",
209 		ahd_aic7902_setup
210 	},
211 	{
212 		ID_AHA_29320B,
213 		ID_ALL_MASK,
214 		"Adaptec 29320B Ultra320 SCSI adapter",
215 		ahd_aic7902_setup
216 	},
217 	/* Generic chip probes for devices we don't know 'exactly' */
218 	{
219 		ID_AIC7901 & ID_DEV_VENDOR_MASK,
220 		ID_DEV_VENDOR_MASK,
221 		"Adaptec AIC7901 Ultra320 SCSI adapter",
222 		ahd_aic7901_setup
223 	},
224 	{
225 		ID_AIC7901A & ID_DEV_VENDOR_MASK,
226 		ID_DEV_VENDOR_MASK,
227 		"Adaptec AIC7901A Ultra320 SCSI adapter",
228 		ahd_aic7901A_setup
229 	},
230 	{
231 		ID_AIC7902 & ID_9005_GENERIC_MASK,
232 		ID_9005_GENERIC_MASK,
233 		"Adaptec AIC7902 Ultra320 SCSI adapter",
234 		ahd_aic7902_setup
235 	}
236 };
237 
238 const u_int ahd_num_pci_devs = NUM_ELEMENTS(ahd_pci_ident_table);
239 
240 #define	                DEVCONFIG		0x40
241 #define		        PCIXINITPAT	        0x0000E000ul
242 #define			PCIXINIT_PCI33_66	0x0000E000ul
243 #define			PCIXINIT_PCIX50_66	0x0000C000ul
244 #define			PCIXINIT_PCIX66_100	0x0000A000ul
245 #define			PCIXINIT_PCIX100_133	0x00008000ul
246 #define	PCI_BUS_MODES_INDEX(devconfig)	\
247 	(((devconfig) & PCIXINITPAT) >> 13)
248 
249 static const char *pci_bus_modes[] =
250 {
251 	"PCI bus mode unknown",
252 	"PCI bus mode unknown",
253 	"PCI bus mode unknown",
254 	"PCI bus mode unknown",
255 	"PCI-X 101-133Mhz",
256 	"PCI-X 67-100Mhz",
257 	"PCI-X 50-66Mhz",
258 	"PCI 33 or 66Mhz"
259 };
260 
261 #define		TESTMODE	0x00000800ul
262 #define		IRDY_RST	0x00000200ul
263 #define		FRAME_RST	0x00000100ul
264 #define		PCI64BIT	0x00000080ul
265 #define		MRDCEN		0x00000040ul
266 #define		ENDIANSEL	0x00000020ul
267 #define		MIXQWENDIANEN	0x00000008ul
268 #define		DACEN		0x00000004ul
269 #define		STPWLEVEL	0x00000002ul
270 #define		QWENDIANSEL	0x00000001ul
271 
272 #define	        DEVCONFIG1     	0x44
273 #define		PREQDIS		0x01
274 
275 #define		LATTIME		0x0000ff00ul
276 
277 int	ahd_pci_probe __P((struct device *, struct cfdata *, void *));
278 void	ahd_pci_attach __P((struct device *, struct device *, void *));
279 
280 CFATTACH_DECL(ahd_pci, sizeof(struct ahd_softc),
281     ahd_pci_probe, ahd_pci_attach, NULL, NULL);
282 
283 static int	ahd_check_extport(struct ahd_softc *ahd);
284 static void	ahd_configure_termination(struct ahd_softc *ahd,
285 					  u_int adapter_control);
286 static void	ahd_pci_split_intr(struct ahd_softc *ahd, u_int intstat);
287 
288 const struct ahd_pci_identity *
289 ahd_find_pci_device(id, subid)
290 	pcireg_t id, subid;
291 {
292 	u_int64_t  full_id;
293 	const struct	   ahd_pci_identity *entry;
294 	u_int	   i;
295 
296 	full_id = ahd_compose_id(PCI_PRODUCT(id), PCI_VENDOR(id),
297 				 PCI_PRODUCT(subid), PCI_VENDOR(subid));
298 
299 	for (i = 0; i < ahd_num_pci_devs; i++) {
300 		entry = &ahd_pci_ident_table[i];
301 		if (entry->full_id == (full_id & entry->id_mask))
302 			return (entry);
303 	}
304 	return (NULL);
305 }
306 
307 int
308 ahd_pci_probe(parent, match, aux)
309 	struct device *parent;
310 	struct cfdata *match;
311 	void *aux;
312 {
313 	struct pci_attach_args *pa = aux;
314 	const struct	   ahd_pci_identity *entry;
315 	pcireg_t   subid;
316 
317 	subid = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_SUBSYS_ID_REG);
318 	entry = ahd_find_pci_device(pa->pa_id, subid);
319 	return entry != NULL ? 1 : 0;
320 }
321 
322 void
323 ahd_pci_attach(parent, self, aux)
324 	struct device *parent, *self;
325 	void *aux;
326 {
327 	struct pci_attach_args	*pa = aux;
328 	struct ahd_softc       	*ahd = (void *)self;
329 
330 	const struct ahd_pci_identity *entry;
331 
332 	uint32_t	   	devconfig;
333 	pcireg_t	   	command;
334 	int		   	error;
335 	pcireg_t	   	subid;
336 	uint16_t	   	subvendor;
337 	int                	pci_pwrmgmt_cap_reg;
338 	int                	pci_pwrmgmt_csr_reg;
339 	pcireg_t           	reg;
340 	int		   	ioh_valid, ioh2_valid, memh_valid;
341 	pcireg_t           	memtype;
342 	pci_intr_handle_t  	ih;
343 	const char         	*intrstr;
344 	struct ahd_pci_busdata 	*bd;
345 
346 	ahd_set_name(ahd, ahd->sc_dev.dv_xname);
347 	ahd->parent_dmat = pa->pa_dmat;
348 
349 	command = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
350 	subid = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_SUBSYS_ID_REG);
351 	entry = ahd_find_pci_device(pa->pa_id, subid);
352 	if (entry == NULL)
353 		return;
354 
355 	/* Keep information about the PCI bus */
356 	bd = malloc(sizeof (struct ahd_pci_busdata), M_DEVBUF, M_NOWAIT);
357 	if (bd == NULL) {
358 		printf("%s: unable to allocate bus-specific data\n", ahd_name(ahd));
359 		return;
360 	}
361 	memset(bd, 0, sizeof(struct ahd_pci_busdata));
362 
363 	bd->pc = pa->pa_pc;
364 	bd->tag = pa->pa_tag;
365 	bd->func = pa->pa_function;
366 	bd->dev = pa->pa_device;
367 
368 	ahd->bus_data = bd;
369 
370 	ahd->description = entry->name;
371 
372 	ahd->seep_config = malloc(sizeof(*ahd->seep_config),
373 				  M_DEVBUF, M_NOWAIT);
374 	if (ahd->seep_config == NULL) {
375 		printf("%s: cannot malloc seep_config!\n", ahd_name(ahd));
376 		return;
377 	}
378 	memset(ahd->seep_config, 0, sizeof(*ahd->seep_config));
379 
380 	LIST_INIT(&ahd->pending_scbs);
381 	ahd_timer_init(&ahd->reset_timer);
382 	ahd_timer_init(&ahd->stat_timer);
383 	ahd->int_coalescing_timer = AHD_INT_COALESCING_TIMER_DEFAULT;
384 	ahd->int_coalescing_maxcmds = AHD_INT_COALESCING_MAXCMDS_DEFAULT;
385 	ahd->int_coalescing_mincmds = AHD_INT_COALESCING_MINCMDS_DEFAULT;
386 	ahd->int_coalescing_threshold = AHD_INT_COALESCING_THRESHOLD_DEFAULT;
387 	ahd->int_coalescing_stop_threshold = AHD_INT_COALESCING_STOP_THRESHOLD_DEFAULT;
388 
389 	if (ahd_platform_alloc(ahd, NULL) != 0) {
390                 ahd_free(ahd);
391                 return;
392         }
393 
394 	/*
395 	 * Record if this is an HP board.
396 	 */
397 	subvendor = PCI_VENDOR(subid);
398 	if (subvendor == SUBID_HP)
399 		ahd->flags |= AHD_HP_BOARD;
400 
401 	error = entry->setup(ahd, pa);
402 	if (error != 0)
403 		return;
404 
405 	devconfig = pci_conf_read(pa->pa_pc, pa->pa_tag, DEVCONFIG);
406 	if ((devconfig & PCIXINITPAT) == PCIXINIT_PCI33_66 ||
407 		(devconfig & PCIXINITPAT) == PCIXINIT_PCIX66_100) {
408 		ahd->chip |= AHD_PCI;
409 		/* Disable PCIX workarounds when running in PCI mode. */
410 		ahd->bugs &= ~AHD_PCIX_BUG_MASK;
411 	} else {
412 		ahd->chip |= AHD_PCIX;
413 	}
414 	ahd->bus_description = pci_bus_modes[PCI_BUS_MODES_INDEX(devconfig)];
415 
416 	memh_valid = ioh_valid = ioh2_valid = 0;
417 
418 	if (!pci_get_capability(pa->pa_pc, pa->pa_tag, PCI_CAP_PCIX,
419 	    &bd->pcix_off, NULL)) {
420 		if (ahd->chip & AHD_PCIX)
421 			printf("%s: warning: can't find PCI-X capability\n",
422 			    ahd->sc_dev.dv_xname);
423 		ahd->chip &= ~AHD_PCIX;
424 		ahd->chip |= AHD_PCI;
425 		ahd->bugs &= ~AHD_PCIX_BUG_MASK;
426 	}
427 
428 	/*
429 	 * Map PCI Registers
430 	 */
431 	if ((command & (PCI_COMMAND_MEM_ENABLE)) != 0) {
432 		memtype = pci_mapreg_type(pa->pa_pc, pa->pa_tag, AHD_PCI_MEMADDR);
433 		switch (memtype) {
434 		case PCI_MAPREG_TYPE_MEM | PCI_MAPREG_MEM_TYPE_32BIT:
435 		case PCI_MAPREG_TYPE_MEM | PCI_MAPREG_MEM_TYPE_64BIT:
436 			memh_valid = (pci_mapreg_map(pa, AHD_PCI_MEMADDR,
437 						     memtype, 0, &ahd->tags[0],
438 						     &ahd->bshs[0], NULL, NULL) == 0);
439 
440 			ahd->tags[1] = ahd->tags[0];
441 
442 			bus_space_subregion(ahd->tags[0], ahd->bshs[0],
443 					    /*offset*/0x100,
444 					    /*size*/0x100,
445 					    &ahd->bshs[1]);
446 			break;
447 		default:
448 			printf("%s: unable to map memory registers\n", ahd_name(ahd));
449 			return;
450 		}
451 
452 		if (memh_valid) {
453 			command &= ~PCI_COMMAND_IO_ENABLE;
454                         pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, command);
455 		}
456 #ifdef AHD_DEBUG
457 		printf("%s: doing memory mapping tag0 0x%x, tag1 0x%x, shs0 0x%lx, shs1 0x%lx\n",
458 			 ahd_name(ahd), ahd->tags[0], ahd->tags[1], ahd->bshs[0], ahd->bshs[1]);
459 #endif
460 	}
461 
462 	if ((command & (PCI_COMMAND_IO_ENABLE)) != 0 &&
463 	    !(ahd->bugs & AHD_PCIX_MMAPIO_BUG)) {
464 		memtype = pci_mapreg_type(pa->pa_pc, pa->pa_tag, AHD_PCI_IOADDR);
465 
466 		/* First BAR */
467 		ioh_valid = (pci_mapreg_map(pa, AHD_PCI_IOADDR,
468 					    memtype, 0, &ahd->tags[0],
469 					    &ahd->bshs[0], NULL, NULL) == 0);
470 
471 		memtype = pci_mapreg_type(pa->pa_pc, pa->pa_tag, AHD_PCI_IOADDR1);
472 
473 		/* 2nd BAR */
474 		ioh2_valid = (pci_mapreg_map(pa, AHD_PCI_IOADDR1,
475 					     memtype, 0, &ahd->tags[1],
476 					     &ahd->bshs[1], NULL, NULL) == 0);
477 
478 		if (ioh_valid && ioh2_valid) {
479 			command &= ~PCI_COMMAND_MEM_ENABLE;
480                         pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, command);
481 		}
482 #ifdef AHD_DEBUG
483 		printf("%s: doing io mapping tag0 0x%x, tag1 0x%x, shs0 0x%lx, shs1 0x%lx\n",
484 			 ahd_name(ahd), ahd->tags[0], ahd->tags[1], ahd->bshs[0], ahd->bshs[1]);
485 #endif
486 
487 	}
488 
489 	if ((memh_valid == 0) && ((ioh_valid == 0) || (ioh2_valid == 0))) {
490 		printf("%s: unable to map memory registers\n", ahd_name(ahd));
491 		return;
492 	}
493 
494 	printf("\n");
495 
496 	/*
497          * Set Power State D0.
498          */
499 	if (pci_get_capability(pa->pa_pc, pa->pa_tag, PCI_CAP_PWRMGMT,
500 			       &pci_pwrmgmt_cap_reg, 0)) {
501 
502 	  	pci_pwrmgmt_csr_reg = pci_pwrmgmt_cap_reg + 4;
503 		reg = pci_conf_read(pa->pa_pc, pa->pa_tag,
504                                     pci_pwrmgmt_csr_reg);
505 		if ((reg & PCI_PMCSR_STATE_MASK) != PCI_PMCSR_STATE_D0) {
506                         pci_conf_write(pa->pa_pc, pa->pa_tag, pci_pwrmgmt_csr_reg,
507                                        (reg & ~PCI_PMCSR_STATE_MASK) |
508                                        PCI_PMCSR_STATE_D0);
509                 }
510         }
511 
512 	/*
513          * Should we bother disabling 39Bit addressing
514          * based on installed memory?
515          */
516         if (sizeof(bus_addr_t) > 4)
517         	ahd->flags |= AHD_39BIT_ADDRESSING;
518 
519 	/*
520 	 * If we need to support high memory, enable dual
521 	 * address cycles.  This bit must be set to enable
522 	 * high address bit generation even if we are on a
523 	 * 64bit bus (PCI64BIT set in devconfig).
524 	 */
525 	if ((ahd->flags & (AHD_39BIT_ADDRESSING|AHD_64BIT_ADDRESSING)) != 0) {
526 		uint32_t devconfig;
527 
528 		printf("%s: Enabling 39Bit Addressing\n", ahd_name(ahd));
529 		devconfig = pci_conf_read(pa->pa_pc, pa->pa_tag, DEVCONFIG);
530 		devconfig |= DACEN;
531 		pci_conf_write(pa->pa_pc, pa->pa_tag, DEVCONFIG, devconfig);
532 	}
533 
534 	/* Ensure busmastering is enabled */
535         reg = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
536         pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
537 		       reg | PCI_COMMAND_MASTER_ENABLE);
538 
539 	ahd_softc_init(ahd);
540 
541 	/*
542 	 * Map the interrupt routines
543 	 */
544 	ahd->bus_intr = ahd_pci_intr;
545 
546 	if (pci_intr_map(pa, &ih)) {
547 		printf("%s: couldn't map interrupt\n", ahd_name(ahd));
548 		ahd_free(ahd);
549 		return;
550 	}
551 	intrstr = pci_intr_string(pa->pa_pc, ih);
552 	ahd->ih = pci_intr_establish(pa->pa_pc, ih, IPL_BIO, ahd_intr, ahd);
553 	if (ahd->ih == NULL) {
554 		printf("%s: couldn't establish interrupt",
555 		       ahd_name(ahd));
556 		if (intrstr != NULL)
557 			printf(" at %s", intrstr);
558 		printf("\n");
559 		ahd_free(ahd);
560 		return;
561 	}
562 	if (intrstr != NULL)
563 		printf("%s: interrupting at %s\n", ahd_name(ahd),
564 		       intrstr);
565 
566 	/* Get the size of the cache */
567 	ahd->pci_cachesize = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_BHLC_REG);
568 	ahd->pci_cachesize *= 4;
569 
570  	ahd_set_modes(ahd, AHD_MODE_SCSI, AHD_MODE_SCSI);
571 	/* See if we have a SEEPROM and perform auto-term */
572 	error = ahd_check_extport(ahd);
573 	if (error != 0)
574 		return;
575 
576 	/* Core initialization */
577 	error = ahd_init(ahd);
578 	if (error != 0)
579 		return;
580 
581 	/*
582 	 * Link this softc in with all other ahd instances.
583 	 */
584 	ahd_attach(ahd);
585 
586 	return;
587 }
588 
589 
590 /*
591  * Check the external port logic for a serial eeprom
592  * and termination/cable detection contrls.
593  */
594 static int
595 ahd_check_extport(struct ahd_softc *ahd)
596 {
597 	struct	vpd_config vpd;
598 	struct	seeprom_config *sc;
599 	u_int	adapter_control;
600 	int	have_seeprom;
601 	int	error;
602 
603 	sc = ahd->seep_config;
604 	have_seeprom = ahd_acquire_seeprom(ahd);
605 	if (have_seeprom) {
606 		u_int start_addr;
607 
608 		/*
609 		 * Fetch VPD for this function and parse it.
610 		 */
611 #ifdef AHD_DEBUG
612 		printf("%s: Reading VPD from SEEPROM...",
613 		       ahd_name(ahd));
614 #endif
615 		/* Address is always in units of 16bit words */
616 		start_addr = ((2 * sizeof(*sc))
617 			    + (sizeof(vpd) * (ahd->channel - 'A'))) / 2;
618 
619 		error = ahd_read_seeprom(ahd, (uint16_t *)&vpd,
620 					 start_addr, sizeof(vpd)/2,
621 					 /*bytestream*/TRUE);
622 		if (error == 0)
623 			error = ahd_parse_vpddata(ahd, &vpd);
624 #ifdef AHD_DEBUG
625 		printf("%s: VPD parsing %s\n",
626 		       ahd_name(ahd),
627 		       error == 0 ? "successful" : "failed");
628 #endif
629 
630 #ifdef AHD_DEBUG
631 		printf("%s: Reading SEEPROM...", ahd_name(ahd));
632 #endif
633 
634 		/* Address is always in units of 16bit words */
635 		start_addr = (sizeof(*sc) / 2) * (ahd->channel - 'A');
636 
637 		error = ahd_read_seeprom(ahd, (uint16_t *)sc,
638 					 start_addr, sizeof(*sc)/2,
639 					 /*bytestream*/FALSE);
640 
641 		if (error != 0) {
642 #ifdef AHD_DEBUG
643 			printf("Unable to read SEEPROM\n");
644 #endif
645 			have_seeprom = 0;
646 		} else {
647 			have_seeprom = ahd_verify_cksum(sc);
648 #ifdef AHD_DEBUG
649 			if (have_seeprom == 0)
650 				printf ("checksum error\n");
651 			else
652 				printf ("done.\n");
653 #endif
654 		}
655 		ahd_release_seeprom(ahd);
656 	}
657 
658 	if (!have_seeprom) {
659 		u_int	  nvram_scb;
660 
661 		/*
662 		 * Pull scratch ram settings and treat them as
663 		 * if they are the contents of an seeprom if
664 		 * the 'ADPT', 'BIOS', or 'ASPI' signature is found
665 		 * in SCB 0xFF.  We manually compose the data as 16bit
666 		 * values to avoid endian issues.
667 		 */
668 		ahd_set_scbptr(ahd, 0xFF);
669 		nvram_scb = ahd_inb_scbram(ahd, SCB_BASE + NVRAM_SCB_OFFSET);
670 		if (nvram_scb != 0xFF
671 		 && ((ahd_inb_scbram(ahd, SCB_BASE + 0) == 'A'
672 		   && ahd_inb_scbram(ahd, SCB_BASE + 1) == 'D'
673 		   && ahd_inb_scbram(ahd, SCB_BASE + 2) == 'P'
674 		   && ahd_inb_scbram(ahd, SCB_BASE + 3) == 'T')
675 		  || (ahd_inb_scbram(ahd, SCB_BASE + 0) == 'B'
676 		   && ahd_inb_scbram(ahd, SCB_BASE + 1) == 'I'
677 		   && ahd_inb_scbram(ahd, SCB_BASE + 2) == 'O'
678 		   && ahd_inb_scbram(ahd, SCB_BASE + 3) == 'S')
679 		  || (ahd_inb_scbram(ahd, SCB_BASE + 0) == 'A'
680 		   && ahd_inb_scbram(ahd, SCB_BASE + 1) == 'S'
681 		   && ahd_inb_scbram(ahd, SCB_BASE + 2) == 'P'
682 		   && ahd_inb_scbram(ahd, SCB_BASE + 3) == 'I'))) {
683 			uint16_t *sc_data;
684 			int	  i;
685 
686 			ahd_set_scbptr(ahd, nvram_scb);
687 			sc_data = (uint16_t *)sc;
688 			for (i = 0; i < 64; i += 2)
689 				*sc_data++ = ahd_inw_scbram(ahd, SCB_BASE+i);
690 			have_seeprom = ahd_verify_cksum(sc);
691 			if (have_seeprom)
692 				ahd->flags |= AHD_SCB_CONFIG_USED;
693 		}
694 	}
695 
696 #ifdef AHD_DEBUG
697 	if ((have_seeprom != 0)	 && (ahd_debug & AHD_DUMP_SEEPROM) != 0) {
698 		uint16_t *sc_data;
699 		int	  i;
700 
701 		printf("%s: Seeprom Contents:", ahd_name(ahd));
702 		sc_data = (uint16_t *)sc;
703 		for (i = 0; i < (sizeof(*sc)); i += 2)
704 			printf("\n\t0x%.4x", sc_data[i]);
705 		printf("\n");
706 	}
707 #endif
708 
709 	if (!have_seeprom) {
710 		printf("%s: No SEEPROM available.\n", ahd_name(ahd));
711 		ahd->flags |= AHD_USEDEFAULTS;
712 		error = ahd_default_config(ahd);
713 		adapter_control = CFAUTOTERM|CFSEAUTOTERM;
714 		free(ahd->seep_config, M_DEVBUF);
715 		ahd->seep_config = NULL;
716 	} else {
717 		error = ahd_parse_cfgdata(ahd, sc);
718 		adapter_control = sc->adapter_control;
719 	}
720 	if (error != 0)
721 		return (error);
722 
723 	ahd_configure_termination(ahd, adapter_control);
724 
725 	return (0);
726 }
727 
728 static void
729 ahd_configure_termination(struct ahd_softc *ahd, u_int adapter_control)
730 {
731 	int	 error;
732 	u_int	 sxfrctl1;
733 	uint8_t	 termctl;
734 	uint32_t devconfig;
735 	struct ahd_pci_busdata 	*bd = ahd->bus_data;
736 
737 	devconfig = pci_conf_read(bd->pc, bd->tag, DEVCONFIG);
738 	devconfig &= ~STPWLEVEL;
739 	if ((ahd->flags & AHD_STPWLEVEL_A) != 0)
740 		devconfig |= STPWLEVEL;
741 #ifdef AHD_DEBUG
742 	printf("%s: STPWLEVEL is %s\n",
743 	       ahd_name(ahd), (devconfig & STPWLEVEL) ? "on" : "off");
744 #endif
745 	pci_conf_write(bd->pc, bd->tag, DEVCONFIG, devconfig);
746 
747 	/* Make sure current sensing is off. */
748 	if ((ahd->flags & AHD_CURRENT_SENSING) != 0) {
749 		(void)ahd_write_flexport(ahd, FLXADDR_ROMSTAT_CURSENSECTL, 0);
750 	}
751 
752 	/*
753 	 * Read to sense.  Write to set.
754 	 */
755 	error = ahd_read_flexport(ahd, FLXADDR_TERMCTL, &termctl);
756 	if ((adapter_control & CFAUTOTERM) == 0) {
757 		printf("%s: Manual Primary Termination\n",
758 		       ahd_name(ahd));
759 		termctl &= ~(FLX_TERMCTL_ENPRILOW|FLX_TERMCTL_ENPRIHIGH);
760 		if ((adapter_control & CFSTERM) != 0)
761 			termctl |= FLX_TERMCTL_ENPRILOW;
762 		if ((adapter_control & CFWSTERM) != 0)
763 			termctl |= FLX_TERMCTL_ENPRIHIGH;
764 	} else if (error != 0) {
765 		printf("%s: Primary Auto-Term Sensing failed! "
766 		       "Using Defaults.\n", ahd_name(ahd));
767 		termctl = FLX_TERMCTL_ENPRILOW|FLX_TERMCTL_ENPRIHIGH;
768 	}
769 
770 	if ((adapter_control & CFSEAUTOTERM) == 0) {
771 		printf("%s: Manual Secondary Termination\n",
772 		       ahd_name(ahd));
773 		termctl &= ~(FLX_TERMCTL_ENSECLOW|FLX_TERMCTL_ENSECHIGH);
774 		if ((adapter_control & CFSELOWTERM) != 0)
775 			termctl |= FLX_TERMCTL_ENSECLOW;
776 		if ((adapter_control & CFSEHIGHTERM) != 0)
777 			termctl |= FLX_TERMCTL_ENSECHIGH;
778 	} else if (error != 0) {
779 		printf("%s: Secondary Auto-Term Sensing failed! "
780 		       "Using Defaults.\n", ahd_name(ahd));
781 		termctl |= FLX_TERMCTL_ENSECLOW|FLX_TERMCTL_ENSECHIGH;
782 	}
783 
784 	/*
785 	 * Now set the termination based on what we found.
786 	 */
787 	sxfrctl1 = ahd_inb(ahd, SXFRCTL1) & ~STPWEN;
788 	if ((termctl & FLX_TERMCTL_ENPRILOW) != 0) {
789 		ahd->flags |= AHD_TERM_ENB_A;
790 		sxfrctl1 |= STPWEN;
791 	}
792 	/* Must set the latch once in order to be effective. */
793 	ahd_outb(ahd, SXFRCTL1, sxfrctl1|STPWEN);
794 	ahd_outb(ahd, SXFRCTL1, sxfrctl1);
795 
796 	error = ahd_write_flexport(ahd, FLXADDR_TERMCTL, termctl);
797 	if (error != 0) {
798 		printf("%s: Unable to set termination settings!\n",
799 		       ahd_name(ahd));
800 	} else {
801 		printf("%s: Primary High byte termination %sabled\n",
802 		       ahd_name(ahd),
803 		       (termctl & FLX_TERMCTL_ENPRIHIGH) ? "En" : "Dis");
804 
805 		printf("%s: Primary Low byte termination %sabled\n",
806 		       ahd_name(ahd),
807 		       (termctl & FLX_TERMCTL_ENPRILOW) ? "En" : "Dis");
808 
809 		printf("%s: Secondary High byte termination %sabled\n",
810 		       ahd_name(ahd),
811 		       (termctl & FLX_TERMCTL_ENSECHIGH) ? "En" : "Dis");
812 
813 		printf("%s: Secondary Low byte termination %sabled\n",
814 		       ahd_name(ahd),
815 		       (termctl & FLX_TERMCTL_ENSECLOW) ? "En" : "Dis");
816 	}
817 	return;
818 }
819 
820 #define	DPE	0x80
821 #define SSE	0x40
822 #define	RMA	0x20
823 #define	RTA	0x10
824 #define STA	0x08
825 #define DPR	0x01
826 
827 static const char *split_status_source[] =
828 {
829 	"DFF0",
830 	"DFF1",
831 	"OVLY",
832 	"CMC",
833 };
834 
835 static const char *pci_status_source[] =
836 {
837 	"DFF0",
838 	"DFF1",
839 	"SG",
840 	"CMC",
841 	"OVLY",
842 	"NONE",
843 	"MSI",
844 	"TARG"
845 };
846 
847 static const char *split_status_strings[] =
848 {
849   	"%s: Received split response in %s.\n",
850 	"%s: Received split completion error message in %s\n",
851 	"%s: Receive overrun in %s\n",
852 	"%s: Count not complete in %s\n",
853 	"%s: Split completion data bucket in %s\n",
854 	"%s: Split completion address error in %s\n",
855 	"%s: Split completion byte count error in %s\n",
856 	"%s: Signaled Target-abort to early terminate a split in %s\n"
857 };
858 
859 static const char *pci_status_strings[] =
860 {
861 	"%s: Data Parity Error has been reported via PERR# in %s\n",
862 	"%s: Target initial wait state error in %s\n",
863 	"%s: Split completion read data parity error in %s\n",
864 	"%s: Split completion address attribute parity error in %s\n",
865 	"%s: Received a Target Abort in %s\n",
866 	"%s: Received a Master Abort in %s\n",
867 	"%s: Signal System Error Detected in %s\n",
868 	"%s: Address or Write Phase Parity Error Detected in %s.\n"
869 };
870 
871 int
872 ahd_pci_intr(struct ahd_softc *ahd)
873 {
874 	uint8_t			pci_status[8];
875 	ahd_mode_state		saved_modes;
876 	u_int			pci_status1;
877 	u_int			intstat;
878 	u_int			i;
879 	u_int			reg;
880 	struct ahd_pci_busdata 	*bd = ahd->bus_data;
881 
882 	intstat = ahd_inb(ahd, INTSTAT);
883 
884 	if ((intstat & SPLTINT) != 0)
885 		ahd_pci_split_intr(ahd, intstat);
886 
887 	if ((intstat & PCIINT) == 0)
888 		return 0;
889 
890 	printf("%s: PCI error Interrupt\n", ahd_name(ahd));
891 	saved_modes = ahd_save_modes(ahd);
892 	ahd_dump_card_state(ahd);
893 	ahd_set_modes(ahd, AHD_MODE_CFG, AHD_MODE_CFG);
894 	for (i = 0, reg = DF0PCISTAT; i < 8; i++, reg++) {
895 
896 		if (i == 5)
897 			continue;
898 		pci_status[i] = ahd_inb(ahd, reg);
899 		/* Clear latched errors.  So our interrupt deasserts. */
900 		ahd_outb(ahd, reg, pci_status[i]);
901 	}
902 
903 	for (i = 0; i < 8; i++) {
904 		u_int bit;
905 
906 		if (i == 5)
907 			continue;
908 
909 		for (bit = 0; bit < 8; bit++) {
910 
911 			if ((pci_status[i] & (0x1 << bit)) != 0) {
912 				static const char *s;
913 
914 				s = pci_status_strings[bit];
915 				if (i == 7/*TARG*/ && bit == 3)
916 					s = "%s: Signaled Target Abort\n";
917 				printf(s, ahd_name(ahd), pci_status_source[i]);
918 			}
919 		}
920 	}
921 	pci_status1 = pci_conf_read(bd->pc, bd->tag, PCI_COMMAND_STATUS_REG);
922 	pci_conf_write(bd->pc, bd->tag, PCI_COMMAND_STATUS_REG , pci_status1);
923 
924 	ahd_restore_modes(ahd, saved_modes);
925 	ahd_outb(ahd, CLRINT, CLRPCIINT);
926 	ahd_unpause(ahd);
927 
928 	return 1;
929 }
930 
931 static void
932 ahd_pci_split_intr(struct ahd_softc *ahd, u_int intstat)
933 {
934 	uint8_t			split_status[4];
935 	uint8_t			split_status1[4];
936 	uint8_t			sg_split_status[2];
937 	uint8_t			sg_split_status1[2];
938 	ahd_mode_state		saved_modes;
939 	u_int			i;
940 	pcireg_t		pcix_status;
941 	struct ahd_pci_busdata 	*bd = ahd->bus_data;
942 
943 	/*
944 	 * Check for splits in all modes.  Modes 0 and 1
945 	 * additionally have SG engine splits to look at.
946 	 */
947 	pcix_status = pci_conf_read(bd->pc, bd->tag,
948 	    bd->pcix_off + PCI_PCIX_STATUS);
949 	printf("%s: PCI Split Interrupt - PCI-X status = 0x%x\n",
950 	       ahd_name(ahd), pcix_status);
951 
952 	saved_modes = ahd_save_modes(ahd);
953 	for (i = 0; i < 4; i++) {
954 		ahd_set_modes(ahd, i, i);
955 
956 		split_status[i] = ahd_inb(ahd, DCHSPLTSTAT0);
957 		split_status1[i] = ahd_inb(ahd, DCHSPLTSTAT1);
958 		/* Clear latched errors.  So our interrupt deasserts. */
959 		ahd_outb(ahd, DCHSPLTSTAT0, split_status[i]);
960 		ahd_outb(ahd, DCHSPLTSTAT1, split_status1[i]);
961 		if (i > 1)
962 			continue;
963 		sg_split_status[i] = ahd_inb(ahd, SGSPLTSTAT0);
964 		sg_split_status1[i] = ahd_inb(ahd, SGSPLTSTAT1);
965 		/* Clear latched errors.  So our interrupt deasserts. */
966 		ahd_outb(ahd, SGSPLTSTAT0, sg_split_status[i]);
967 		ahd_outb(ahd, SGSPLTSTAT1, sg_split_status1[i]);
968 	}
969 
970 	for (i = 0; i < 4; i++) {
971 		u_int bit;
972 
973 		for (bit = 0; bit < 8; bit++) {
974 
975 			if ((split_status[i] & (0x1 << bit)) != 0) {
976 				static const char *s;
977 
978 				s = split_status_strings[bit];
979 				printf(s, ahd_name(ahd),
980 				       split_status_source[i]);
981 			}
982 
983 			if (i > 0)
984 				continue;
985 
986 			if ((sg_split_status[i] & (0x1 << bit)) != 0) {
987 				static const char *s;
988 
989 				s = split_status_strings[bit];
990 				printf(s, ahd_name(ahd), "SG");
991 			}
992 		}
993 	}
994 	/*
995 	 * Clear PCI-X status bits.
996 	 */
997 	pci_conf_write(bd->pc, bd->tag, bd->pcix_off + PCI_PCIX_STATUS,
998 	    pcix_status);
999 	ahd_outb(ahd, CLRINT, CLRSPLTINT);
1000 	ahd_restore_modes(ahd, saved_modes);
1001 }
1002 
1003 static int
1004 ahd_aic7901_setup(struct ahd_softc *ahd, struct pci_attach_args *pa)
1005 {
1006 
1007 	ahd->chip = AHD_AIC7901;
1008 	ahd->features = AHD_AIC7901_FE;
1009 	return (ahd_aic790X_setup(ahd, pa));
1010 }
1011 
1012 static int
1013 ahd_aic7901A_setup(struct ahd_softc *ahd, struct pci_attach_args *pa)
1014 {
1015 
1016 	ahd->chip = AHD_AIC7901A;
1017 	ahd->features = AHD_AIC7901A_FE;
1018 	return (ahd_aic790X_setup(ahd, pa));
1019 }
1020 
1021 static int
1022 ahd_aic7902_setup(struct ahd_softc *ahd, struct pci_attach_args *pa)
1023 {
1024 
1025 	ahd->chip = AHD_AIC7902;
1026 	ahd->features = AHD_AIC7902_FE;
1027 	return (ahd_aic790X_setup(ahd, pa));
1028 }
1029 
1030 static int
1031 ahd_aic790X_setup(struct ahd_softc *ahd, struct pci_attach_args	*pa)
1032 {
1033 	u_int rev;
1034 
1035 	rev = PCI_REVISION(pa->pa_class);
1036 #ifdef AHD_DEBUG
1037 	printf("\n%s: aic7902 chip revision 0x%x\n", ahd_name(ahd), rev);
1038 #endif
1039 	if (rev < ID_AIC7902_PCI_REV_A4) {
1040 		printf("%s: Unable to attach to unsupported chip revision %d\n",
1041 		       ahd_name(ahd), rev);
1042 		pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, 0);
1043 		return (ENXIO);
1044 	}
1045 
1046 	ahd->channel = (pa->pa_function == 1) ? 'B' : 'A';
1047 	if (rev < ID_AIC7902_PCI_REV_B0) {
1048 		/*
1049 		 * Enable A series workarounds.
1050 		 */
1051 		ahd->bugs |= AHD_SENT_SCB_UPDATE_BUG|AHD_ABORT_LQI_BUG
1052 			  |  AHD_PKT_BITBUCKET_BUG|AHD_LONG_SETIMO_BUG
1053 			  |  AHD_NLQICRC_DELAYED_BUG|AHD_SCSIRST_BUG
1054 			  |  AHD_LQO_ATNO_BUG|AHD_AUTOFLUSH_BUG
1055 			  |  AHD_CLRLQO_AUTOCLR_BUG|AHD_PCIX_MMAPIO_BUG
1056 			  |  AHD_PCIX_CHIPRST_BUG|AHD_PCIX_SCBRAM_RD_BUG
1057 			  |  AHD_PKTIZED_STATUS_BUG|AHD_PKT_LUN_BUG
1058 			  |  AHD_MDFF_WSCBPTR_BUG|AHD_REG_SLOW_SETTLE_BUG
1059 			  |  AHD_SET_MODE_BUG|AHD_BUSFREEREV_BUG
1060 			  |  AHD_NONPACKFIFO_BUG|AHD_PACED_NEGTABLE_BUG
1061 			  |  AHD_FAINT_LED_BUG;
1062 
1063 
1064 		/*
1065 		 * IO Cell paramter setup.
1066 		 */
1067 		AHD_SET_PRECOMP(ahd, AHD_PRECOMP_CUTBACK_29);
1068 
1069 		if ((ahd->flags & AHD_HP_BOARD) == 0)
1070 			AHD_SET_SLEWRATE(ahd, AHD_SLEWRATE_DEF_REVA);
1071 	} else {
1072 		u_int devconfig1;
1073 
1074 		ahd->features |= AHD_RTI|AHD_NEW_IOCELL_OPTS
1075 			      |  AHD_NEW_DFCNTRL_OPTS;
1076 		ahd->bugs |= AHD_LQOOVERRUN_BUG|AHD_EARLY_REQ_BUG;
1077 
1078 		/*
1079 		 * Some issues have been resolved in the 7901B.
1080 		 */
1081 		if ((ahd->features & AHD_MULTI_FUNC) != 0)
1082 			ahd->bugs |= AHD_INTCOLLISION_BUG|AHD_ABORT_LQI_BUG;
1083 
1084 		/*
1085 		 * IO Cell paramter setup.
1086 		 */
1087 		AHD_SET_PRECOMP(ahd, AHD_PRECOMP_CUTBACK_29);
1088 		AHD_SET_SLEWRATE(ahd, AHD_SLEWRATE_DEF_REVB);
1089 		AHD_SET_AMPLITUDE(ahd, AHD_AMPLITUDE_DEF);
1090 
1091 		/*
1092 		 * Set the PREQDIS bit for H2B which disables some workaround
1093 		 * that doesn't work on regular PCI busses.
1094 		 * XXX - Find out exactly what this does from the hardware
1095 		 * 	 folks!
1096 		 */
1097 		devconfig1 = pci_conf_read(pa->pa_pc, pa->pa_tag, DEVCONFIG1);
1098 		pci_conf_write(pa->pa_pc, pa->pa_tag, DEVCONFIG1, devconfig1|PREQDIS);
1099 		devconfig1 = pci_conf_read(pa->pa_pc, pa->pa_tag, DEVCONFIG1);
1100 	}
1101 
1102 	return (0);
1103 }
1104 
1105