xref: /netbsd-src/sys/dev/pci/pciconf.c (revision b757af438b42b93f8c6571f026d8b8ef3eaf5fc9)
1 /*	$NetBSD: pciconf.c,v 1.34 2012/01/27 18:53:08 para Exp $	*/
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Allen Briggs for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 /*
38  * Derived in part from code from PMON/2000 (http://pmon.groupbsd.org/).
39  */
40 
41 /*
42  * To do:
43  *    - Perform all data structure allocation dynamically, don't have
44  *	statically-sized arrays ("oops, you lose because you have too
45  *	many slots filled!")
46  *    - Do this in 2 passes, with an MD hook to control the behavior:
47  *		(1) Configure the bus (possibly including expansion
48  *		    ROMs.
49  *		(2) Another pass to disable expansion ROMs if they're
50  *		    mapped (since you're not supposed to leave them
51  *		    mapped when you're not using them).
52  *	This would facilitate MD code executing the expansion ROMs
53  *	if necessary (possibly with an x86 emulator) to configure
54  *	devices (e.g. VGA cards).
55  *    - Deal with "anything can be hot-plugged" -- i.e., carry configuration
56  *	information around & be able to reconfigure on the fly
57  *    - Deal with segments (See IA64 System Abstraction Layer)
58  *    - Deal with subtractive bridges (& non-spec positive/subtractive decode)
59  *    - Deal with ISA/VGA/VGA palette snooping
60  *    - Deal with device capabilities on bridges
61  *    - Worry about changing a bridge to/from transparency
62  * From thorpej (05/25/01)
63  *    - Try to handle devices that are already configured (perhaps using that
64  *      as a hint to where we put other devices)
65  */
66 
67 #include <sys/cdefs.h>
68 __KERNEL_RCSID(0, "$NetBSD: pciconf.c,v 1.34 2012/01/27 18:53:08 para Exp $");
69 
70 #include "opt_pci.h"
71 
72 #include <sys/param.h>
73 #include <sys/extent.h>
74 #include <sys/queue.h>
75 #include <sys/systm.h>
76 #include <sys/malloc.h>
77 #include <sys/kmem.h>
78 
79 #include <dev/pci/pcivar.h>
80 #include <dev/pci/pciconf.h>
81 #include <dev/pci/pcidevs.h>
82 #include <dev/pci/pccbbreg.h>
83 
84 int pci_conf_debug = 0;
85 
86 #if !defined(MIN)
87 #define	MIN(a,b) (((a)<(b))?(a):(b))
88 #define	MAX(a,b) (((a)>(b))?(a):(b))
89 #endif
90 
91 /* per-bus constants. */
92 #define MAX_CONF_DEV	32			/* Arbitrary */
93 #define MAX_CONF_MEM	(3 * MAX_CONF_DEV)	/* Avg. 3 per device -- Arb. */
94 #define MAX_CONF_IO	(3 * MAX_CONF_DEV)	/* Avg. 1 per device -- Arb. */
95 
96 struct _s_pciconf_bus_t;			/* Forward declaration */
97 
98 typedef struct _s_pciconf_dev_t {
99 	int		ipin;
100 	int		iline;
101 	int		min_gnt;
102 	int		max_lat;
103 	int		enable;
104 	pcitag_t	tag;
105 	pci_chipset_tag_t	pc;
106 	struct _s_pciconf_bus_t	*ppb;		/* I am really a bridge */
107 } pciconf_dev_t;
108 
109 typedef struct _s_pciconf_win_t {
110 	pciconf_dev_t	*dev;
111 	int		reg;			/* 0 for busses */
112 	int		align;
113 	int		prefetch;
114 	u_int64_t	size;
115 	u_int64_t	address;
116 } pciconf_win_t;
117 
118 typedef struct _s_pciconf_bus_t {
119 	int		busno;
120 	int		next_busno;
121 	int		last_busno;
122 	int		max_mingnt;
123 	int		min_maxlat;
124 	int		cacheline_size;
125 	int		prefetch;
126 	int		fast_b2b;
127 	int		freq_66;
128 	int		def_ltim;
129 	int		max_ltim;
130 	int		bandwidth_used;
131 	int		swiz;
132 	int		io_32bit;
133 	int		pmem_64bit;
134 
135 	int		ndevs;
136 	pciconf_dev_t	device[MAX_CONF_DEV];
137 
138 	/* These should be sorted in order of decreasing size */
139 	int		nmemwin;
140 	pciconf_win_t	pcimemwin[MAX_CONF_MEM];
141 	int		niowin;
142 	pciconf_win_t	pciiowin[MAX_CONF_IO];
143 
144 	bus_size_t	io_total;
145 	bus_size_t	mem_total;
146 	bus_size_t	pmem_total;
147 
148 	struct extent	*ioext;
149 	struct extent	*memext;
150 	struct extent	*pmemext;
151 
152 	pci_chipset_tag_t	pc;
153 	struct _s_pciconf_bus_t *parent_bus;
154 } pciconf_bus_t;
155 
156 static int	probe_bus(pciconf_bus_t *);
157 static void	alloc_busno(pciconf_bus_t *, pciconf_bus_t *);
158 static void	set_busreg(pci_chipset_tag_t, pcitag_t, int, int, int);
159 static int	pci_do_device_query(pciconf_bus_t *, pcitag_t, int, int, int);
160 static int	setup_iowins(pciconf_bus_t *);
161 static int	setup_memwins(pciconf_bus_t *);
162 static int	configure_bridge(pciconf_dev_t *);
163 static int	configure_bus(pciconf_bus_t *);
164 static u_int64_t	pci_allocate_range(struct extent *, u_int64_t, int);
165 static pciconf_win_t	*get_io_desc(pciconf_bus_t *, bus_size_t);
166 static pciconf_win_t	*get_mem_desc(pciconf_bus_t *, bus_size_t);
167 static pciconf_bus_t	*query_bus(pciconf_bus_t *, pciconf_dev_t *, int);
168 
169 static void	print_tag(pci_chipset_tag_t, pcitag_t);
170 
171 static void
172 print_tag(pci_chipset_tag_t pc, pcitag_t tag)
173 {
174 	int	bus, dev, func;
175 
176 	pci_decompose_tag(pc, tag, &bus, &dev, &func);
177 	printf("PCI: bus %d, device %d, function %d: ", bus, dev, func);
178 }
179 
180 /************************************************************************/
181 /************************************************************************/
182 /***********************   Bus probing routines   ***********************/
183 /************************************************************************/
184 /************************************************************************/
185 static pciconf_win_t *
186 get_io_desc(pciconf_bus_t *pb, bus_size_t size)
187 {
188 	int	i, n;
189 
190 	n = pb->niowin;
191 	for (i=n; i > 0 && size > pb->pciiowin[i-1].size; i--)
192 		pb->pciiowin[i] = pb->pciiowin[i-1]; /* struct copy */
193 	return &pb->pciiowin[i];
194 }
195 
196 static pciconf_win_t *
197 get_mem_desc(pciconf_bus_t *pb, bus_size_t size)
198 {
199 	int	i, n;
200 
201 	n = pb->nmemwin;
202 	for (i=n; i > 0 && size > pb->pcimemwin[i-1].size; i--)
203 		pb->pcimemwin[i] = pb->pcimemwin[i-1]; /* struct copy */
204 	return &pb->pcimemwin[i];
205 }
206 
207 /*
208  * Set up bus common stuff, then loop over devices & functions.
209  * If we find something, call pci_do_device_query()).
210  */
211 static int
212 probe_bus(pciconf_bus_t *pb)
213 {
214 	int device;
215 	uint8_t devs[32];
216 	int i, n;
217 
218 	pb->ndevs = 0;
219 	pb->niowin = 0;
220 	pb->nmemwin = 0;
221 	pb->freq_66 = 1;
222 #ifdef PCICONF_NO_FAST_B2B
223 	pb->fast_b2b = 0;
224 #else
225 	pb->fast_b2b = 1;
226 #endif
227 	pb->prefetch = 1;
228 	pb->max_mingnt = 0;	/* we are looking for the maximum */
229 	pb->min_maxlat = 0x100;	/* we are looking for the minimum */
230 	pb->bandwidth_used = 0;
231 
232 	n = pci_bus_devorder(pb->pc, pb->busno, devs, __arraycount(devs));
233 	for (i = 0; i < n; i++) {
234 		pcitag_t tag;
235 		pcireg_t id, bhlcr;
236 		int function, nfunction;
237 		int confmode;
238 
239 		device = devs[i];
240 
241 		tag = pci_make_tag(pb->pc, pb->busno, device, 0);
242 		if (pci_conf_debug) {
243 			print_tag(pb->pc, tag);
244 		}
245 		id = pci_conf_read(pb->pc, tag, PCI_ID_REG);
246 
247 		if (pci_conf_debug) {
248 			printf("id=%x: Vendor=%x, Product=%x\n",
249 			    id, PCI_VENDOR(id),PCI_PRODUCT(id));
250 		}
251 		/* Invalid vendor ID value? */
252 		if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
253 			continue;
254 
255 		bhlcr = pci_conf_read(pb->pc, tag, PCI_BHLC_REG);
256 		nfunction = PCI_HDRTYPE_MULTIFN(bhlcr) ? 8 : 1;
257 		for (function = 0 ; function < nfunction ; function++) {
258 			tag = pci_make_tag(pb->pc, pb->busno, device, function);
259 			id = pci_conf_read(pb->pc, tag, PCI_ID_REG);
260 			if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
261 				continue;
262 			if (pb->ndevs+1 < MAX_CONF_DEV) {
263 				if (pci_conf_debug) {
264 					print_tag(pb->pc, tag);
265 					printf("Found dev 0x%04x 0x%04x -- "
266 					    "really probing.\n",
267 					PCI_VENDOR(id), PCI_PRODUCT(id));
268 				}
269 #ifdef __HAVE_PCI_CONF_HOOK
270 				confmode = pci_conf_hook(pb->pc, pb->busno,
271 				    device, function, id);
272 				if (confmode == 0)
273 					continue;
274 #else
275 				/*
276 				 * Don't enable expansion ROMS -- some cards
277 				 * share address decoders between the EXPROM
278 				 * and PCI memory space, and enabling the ROM
279 				 * when not needed will cause all sorts of
280 				 * lossage.
281 				 */
282 				confmode = PCI_CONF_DEFAULT;
283 #endif
284 				if (pci_do_device_query(pb, tag, device,
285 				    function, confmode))
286 					return -1;
287 				pb->ndevs++;
288 			}
289 		}
290 	}
291 	return 0;
292 }
293 
294 static void
295 alloc_busno(pciconf_bus_t *parent, pciconf_bus_t *pb)
296 {
297 	pb->busno = parent->next_busno;
298 	pb->next_busno = pb->busno + 1;
299 }
300 
301 static void
302 set_busreg(pci_chipset_tag_t pc, pcitag_t tag, int prim, int sec, int sub)
303 {
304 	pcireg_t	busreg;
305 
306 	busreg  =  prim << PCI_BRIDGE_BUS_PRIMARY_SHIFT;
307 	busreg |=   sec << PCI_BRIDGE_BUS_SECONDARY_SHIFT;
308 	busreg |=   sub << PCI_BRIDGE_BUS_SUBORDINATE_SHIFT;
309 	pci_conf_write(pc, tag, PCI_BRIDGE_BUS_REG, busreg);
310 }
311 
312 static pciconf_bus_t *
313 query_bus(pciconf_bus_t *parent, pciconf_dev_t *pd, int dev)
314 {
315 	pciconf_bus_t	*pb;
316 	pcireg_t	io, pmem;
317 	pciconf_win_t	*pi, *pm;
318 
319 	pb = kmem_zalloc(sizeof (pciconf_bus_t), KM_NOSLEEP);
320 	if (!pb)
321 		panic("Unable to allocate memory for PCI configuration.");
322 
323 	pb->cacheline_size = parent->cacheline_size;
324 	pb->parent_bus = parent;
325 	alloc_busno(parent, pb);
326 
327 	set_busreg(parent->pc, pd->tag, parent->busno, pb->busno, 0xff);
328 
329 	pb->swiz = parent->swiz + dev;
330 
331 	pb->ioext = NULL;
332 	pb->memext = NULL;
333 	pb->pmemext = NULL;
334 	pb->pc = parent->pc;
335 	pb->io_total = pb->mem_total = pb->pmem_total = 0;
336 
337 	pb->io_32bit = 0;
338 	if (parent->io_32bit) {
339 		io = pci_conf_read(parent->pc, pd->tag, PCI_BRIDGE_STATIO_REG);
340 		if (PCI_BRIDGE_IO_32BITS(io)) {
341 			pb->io_32bit = 1;
342 		}
343 	}
344 
345 	pb->pmem_64bit = 0;
346 	if (parent->pmem_64bit) {
347 		pmem = pci_conf_read(parent->pc, pd->tag,
348 		    PCI_BRIDGE_PREFETCHMEM_REG);
349 		if (PCI_BRIDGE_PREFETCHMEM_64BITS(pmem)) {
350 			pb->pmem_64bit = 1;
351 		}
352 	}
353 
354 	if (probe_bus(pb)) {
355 		printf("Failed to probe bus %d\n", pb->busno);
356 		goto err;
357 	}
358 
359 	/* We have found all subordinate busses now, reprogram busreg. */
360 	pb->last_busno = pb->next_busno-1;
361 	parent->next_busno = pb->next_busno;
362 	set_busreg(parent->pc, pd->tag, parent->busno, pb->busno,
363 		   pb->last_busno);
364 	if (pci_conf_debug)
365 		printf("PCI bus bridge (parent %d) covers busses %d-%d\n",
366 			parent->busno, pb->busno, pb->last_busno);
367 
368 	if (pb->io_total > 0) {
369 		if (parent->niowin >= MAX_CONF_IO) {
370 			printf("pciconf: too many I/O windows\n");
371 			goto err;
372 		}
373 		pb->io_total |= 0xfff;	/* Round up */
374 		pi = get_io_desc(parent, pb->io_total);
375 		pi->dev = pd;
376 		pi->reg = 0;
377 		pi->size = pb->io_total;
378 		pi->align = 0x1000;	/* 4K alignment */
379 		pi->prefetch = 0;
380 		parent->niowin++;
381 		parent->io_total += pb->io_total;
382 	}
383 
384 	if (pb->mem_total > 0) {
385 		if (parent->nmemwin >= MAX_CONF_MEM) {
386 			printf("pciconf: too many MEM windows\n");
387 			goto err;
388 		}
389 		pb->mem_total |= 0xfffff;	/* Round up */
390 		pm = get_mem_desc(parent, pb->mem_total);
391 		pm->dev = pd;
392 		pm->reg = 0;
393 		pm->size = pb->mem_total;
394 		pm->align = 0x100000;	/* 1M alignment */
395 		pm->prefetch = 0;
396 		parent->nmemwin++;
397 		parent->mem_total += pb->mem_total;
398 	}
399 
400 	if (pb->pmem_total > 0) {
401 		if (parent->nmemwin >= MAX_CONF_MEM) {
402 			printf("pciconf: too many MEM windows\n");
403 			goto err;
404 		}
405 		pb->pmem_total |= 0xfffff;	/* Round up */
406 		pm = get_mem_desc(parent, pb->pmem_total);
407 		pm->dev = pd;
408 		pm->reg = 0;
409 		pm->size = pb->pmem_total;
410 		pm->align = 0x100000;		/* 1M alignment */
411 		pm->prefetch = 1;
412 		parent->nmemwin++;
413 		parent->pmem_total += pb->pmem_total;
414 	}
415 
416 	return pb;
417 err:
418 	kmem_free(pb, sizeof(*pb));
419 	return NULL;
420 }
421 
422 static int
423 pci_do_device_query(pciconf_bus_t *pb, pcitag_t tag, int dev, int func, int mode)
424 {
425 	pciconf_dev_t	*pd;
426 	pciconf_win_t	*pi, *pm;
427 	pcireg_t	class, cmd, icr, bhlc, bar, mask, bar64, mask64, busreg;
428 	u_int64_t	size;
429 	int		br, width, reg_start, reg_end;
430 
431 	pd = &pb->device[pb->ndevs];
432 	pd->pc = pb->pc;
433 	pd->tag = tag;
434 	pd->ppb = NULL;
435 	pd->enable = mode;
436 
437 	class = pci_conf_read(pb->pc, tag, PCI_CLASS_REG);
438 
439 	cmd = pci_conf_read(pb->pc, tag, PCI_COMMAND_STATUS_REG);
440 	bhlc = pci_conf_read(pb->pc, tag, PCI_BHLC_REG);
441 
442 	if (PCI_CLASS(class) != PCI_CLASS_BRIDGE
443 	    && PCI_HDRTYPE_TYPE(bhlc) != PCI_HDRTYPE_PPB) {
444 		cmd &= ~(PCI_COMMAND_MASTER_ENABLE |
445 		    PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
446 		pci_conf_write(pb->pc, tag, PCI_COMMAND_STATUS_REG, cmd);
447 	} else if (pci_conf_debug) {
448 		print_tag(pb->pc, tag);
449 		printf("device is a bridge; not clearing enables\n");
450 	}
451 
452 	if ((cmd & PCI_STATUS_BACKTOBACK_SUPPORT) == 0)
453 		pb->fast_b2b = 0;
454 
455 	if ((cmd & PCI_STATUS_66MHZ_SUPPORT) == 0)
456 		pb->freq_66 = 0;
457 
458 	switch (PCI_HDRTYPE_TYPE(bhlc)) {
459 	case PCI_HDRTYPE_DEVICE:
460 		reg_start = PCI_MAPREG_START;
461 		reg_end = PCI_MAPREG_END;
462 		break;
463 	case PCI_HDRTYPE_PPB:
464 		pd->ppb = query_bus(pb, pd, dev);
465 		if (pd->ppb == NULL)
466 			return -1;
467 		return 0;
468 	case PCI_HDRTYPE_PCB:
469 		reg_start = PCI_MAPREG_START;
470 		reg_end = PCI_MAPREG_PCB_END;
471 
472 		busreg = pci_conf_read(pb->pc, tag, PCI_BUSNUM);
473 		busreg  =  (busreg & 0xff000000) |
474 		    pb->busno << PCI_BRIDGE_BUS_PRIMARY_SHIFT |
475 		    pb->next_busno << PCI_BRIDGE_BUS_SECONDARY_SHIFT |
476 		    pb->next_busno << PCI_BRIDGE_BUS_SUBORDINATE_SHIFT;
477 		pci_conf_write(pb->pc, tag, PCI_BUSNUM, busreg);
478 
479 		pb->next_busno++;
480 		break;
481 	default:
482 		return -1;
483 	}
484 
485 	icr = pci_conf_read(pb->pc, tag, PCI_INTERRUPT_REG);
486 	pd->ipin = PCI_INTERRUPT_PIN(icr);
487 	pd->iline = PCI_INTERRUPT_LINE(icr);
488 	pd->min_gnt = PCI_MIN_GNT(icr);
489 	pd->max_lat = PCI_MAX_LAT(icr);
490 	if (pd->iline || pd->ipin) {
491 		pci_conf_interrupt(pb->pc, pb->busno, dev, pd->ipin, pb->swiz,
492 		    &pd->iline);
493 		icr &= ~(PCI_INTERRUPT_LINE_MASK << PCI_INTERRUPT_LINE_SHIFT);
494 		icr |= (pd->iline << PCI_INTERRUPT_LINE_SHIFT);
495 		pci_conf_write(pb->pc, tag, PCI_INTERRUPT_REG, icr);
496 	}
497 
498 	if (pd->min_gnt != 0 || pd->max_lat != 0) {
499 		if (pd->min_gnt != 0 && pd->min_gnt > pb->max_mingnt)
500 			pb->max_mingnt = pd->min_gnt;
501 
502 		if (pd->max_lat != 0 && pd->max_lat < pb->min_maxlat)
503 			pb->min_maxlat = pd->max_lat;
504 
505 		pb->bandwidth_used += pd->min_gnt * 4000000 /
506 				(pd->min_gnt + pd->max_lat);
507 	}
508 
509 	width = 4;
510 	for (br = reg_start; br < reg_end; br += width) {
511 #if 0
512 /* XXX Should only ignore if IDE not in legacy mode? */
513 		if (PCI_CLASS(class) == PCI_CLASS_MASS_STORAGE &&
514 		    PCI_SUBCLASS(class) == PCI_SUBCLASS_MASS_STORAGE_IDE) {
515 			break;
516 		}
517 #endif
518 		bar = pci_conf_read(pb->pc, tag, br);
519 		pci_conf_write(pb->pc, tag, br, 0xffffffff);
520 		mask = pci_conf_read(pb->pc, tag, br);
521 		pci_conf_write(pb->pc, tag, br, bar);
522 		width = 4;
523 
524 		if (   (mode & PCI_CONF_MAP_IO)
525 		    && (PCI_MAPREG_TYPE(mask) == PCI_MAPREG_TYPE_IO)) {
526 			/*
527 			 * Upper 16 bits must be one.  Devices may hardwire
528 			 * them to zero, though, per PCI 2.2, 6.2.5.1, p 203.
529 			 */
530 			mask |= 0xffff0000;
531 
532 			size = PCI_MAPREG_IO_SIZE(mask);
533 			if (size == 0) {
534 				if (pci_conf_debug) {
535 					print_tag(pb->pc, tag);
536 					printf("I/O BAR 0x%x is void\n", br);
537 				}
538 				continue;
539 			}
540 
541 			if (pb->niowin >= MAX_CONF_IO) {
542 				printf("pciconf: too many I/O windows\n");
543 				return -1;
544 			}
545 
546 			pi = get_io_desc(pb, size);
547 			pi->dev = pd;
548 			pi->reg = br;
549 			pi->size = (u_int64_t) size;
550 			pi->align = 4;
551 			pi->prefetch = 0;
552 			if (pci_conf_debug) {
553 				print_tag(pb->pc, tag);
554 				printf("Register 0x%x, I/O size %" PRIu64 "\n",
555 				    br, pi->size);
556 			}
557 			pb->niowin++;
558 			pb->io_total += size;
559 		} else if ((mode & PCI_CONF_MAP_MEM)
560 			   && (PCI_MAPREG_TYPE(mask) == PCI_MAPREG_TYPE_MEM)) {
561 			switch (PCI_MAPREG_MEM_TYPE(mask)) {
562 			case PCI_MAPREG_MEM_TYPE_32BIT:
563 			case PCI_MAPREG_MEM_TYPE_32BIT_1M:
564 				size = (u_int64_t) PCI_MAPREG_MEM_SIZE(mask);
565 				break;
566 			case PCI_MAPREG_MEM_TYPE_64BIT:
567 				bar64 = pci_conf_read(pb->pc, tag, br + 4);
568 				pci_conf_write(pb->pc, tag, br + 4, 0xffffffff);
569 				mask64 = pci_conf_read(pb->pc, tag, br + 4);
570 				pci_conf_write(pb->pc, tag, br + 4, bar64);
571 				size = (u_int64_t) PCI_MAPREG_MEM64_SIZE(
572 				      (((u_int64_t) mask64) << 32) | mask);
573 				width = 8;
574 				break;
575 			default:
576 				print_tag(pb->pc, tag);
577 				printf("reserved mapping type 0x%x\n",
578 					PCI_MAPREG_MEM_TYPE(mask));
579 				continue;
580 			}
581 
582 			if (size == 0) {
583 				if (pci_conf_debug) {
584 					print_tag(pb->pc, tag);
585 					printf("MEM%d BAR 0x%x is void\n",
586 					    PCI_MAPREG_MEM_TYPE(mask) ==
587 						PCI_MAPREG_MEM_TYPE_64BIT ?
588 						64 : 32, br);
589 				}
590 				continue;
591 			} else {
592 				if (pci_conf_debug) {
593 					print_tag(pb->pc, tag);
594 					printf("MEM%d BAR 0x%x has size %lx\n",
595 					    PCI_MAPREG_MEM_TYPE(mask) ==
596 						PCI_MAPREG_MEM_TYPE_64BIT ?
597 						64 : 32, br, (unsigned long)size);
598 				}
599 			}
600 
601 			if (pb->nmemwin >= MAX_CONF_MEM) {
602 				printf("pciconf: too many memory windows\n");
603 				return -1;
604 			}
605 
606 			pm = get_mem_desc(pb, size);
607 			pm->dev = pd;
608 			pm->reg = br;
609 			pm->size = size;
610 			pm->align = 4;
611 			pm->prefetch = PCI_MAPREG_MEM_PREFETCHABLE(mask);
612 			if (pci_conf_debug) {
613 				print_tag(pb->pc, tag);
614 				printf("Register 0x%x, memory size %"
615 				    PRIu64 "\n", br, pm->size);
616 			}
617 			pb->nmemwin++;
618 			if (pm->prefetch) {
619 				pb->pmem_total += size;
620 			} else {
621 				pb->mem_total += size;
622 			}
623 		}
624 	}
625 
626 	if (mode & PCI_CONF_MAP_ROM) {
627 		bar = pci_conf_read(pb->pc, tag, PCI_MAPREG_ROM);
628 		pci_conf_write(pb->pc, tag, PCI_MAPREG_ROM, 0xfffffffe);
629 		mask = pci_conf_read(pb->pc, tag, PCI_MAPREG_ROM);
630 		pci_conf_write(pb->pc, tag, PCI_MAPREG_ROM, bar);
631 
632 		if (mask != 0 && mask != 0xffffffff) {
633 			if (pb->nmemwin >= MAX_CONF_MEM) {
634 				printf("pciconf: too many memory windows\n");
635 				return -1;
636 			}
637 			size = (u_int64_t) PCI_MAPREG_MEM_SIZE(mask);
638 
639 			pm = get_mem_desc(pb, size);
640 			pm->dev = pd;
641 			pm->reg = PCI_MAPREG_ROM;
642 			pm->size = size;
643 			pm->align = 4;
644 			pm->prefetch = 1;
645 			if (pci_conf_debug) {
646 				print_tag(pb->pc, tag);
647 				printf("Expansion ROM memory size %"
648 				    PRIu64 "\n", pm->size);
649 			}
650 			pb->nmemwin++;
651 			pb->pmem_total += size;
652 		}
653 	} else {
654 		/* Don't enable ROMs if we aren't going to map them. */
655 		mode &= ~PCI_CONF_ENABLE_ROM;
656 		pd->enable &= ~PCI_CONF_ENABLE_ROM;
657 	}
658 
659 	if (!(mode & PCI_CONF_ENABLE_ROM)) {
660 		/* Ensure ROM is disabled */
661 		bar = pci_conf_read(pb->pc, tag, PCI_MAPREG_ROM);
662 		pci_conf_write(pb->pc, tag, PCI_MAPREG_ROM,
663 		    bar & ~PCI_MAPREG_ROM_ENABLE);
664 	}
665 
666 	return 0;
667 }
668 
669 /************************************************************************/
670 /************************************************************************/
671 /********************   Bus configuration routines   ********************/
672 /************************************************************************/
673 /************************************************************************/
674 static u_int64_t
675 pci_allocate_range(struct extent *ex, u_int64_t amt, int align)
676 {
677 	int	r;
678 	u_long	addr;
679 
680 	r = extent_alloc(ex, amt, align, 0, EX_NOWAIT, &addr);
681 	if (r) {
682 		addr = (u_long) -1;
683 		printf("extent_alloc(%p, %" PRIu64 ", %d) returned %d\n",
684 		    ex, amt, align, r);
685 		extent_print(ex);
686 	}
687 	return (pcireg_t) addr;
688 }
689 
690 static int
691 setup_iowins(pciconf_bus_t *pb)
692 {
693 	pciconf_win_t	*pi;
694 	pciconf_dev_t	*pd;
695 
696 	for (pi=pb->pciiowin; pi < &pb->pciiowin[pb->niowin] ; pi++) {
697 		if (pi->size == 0)
698 			continue;
699 
700 		pd = pi->dev;
701 		pi->address = pci_allocate_range(pb->ioext, pi->size,
702 		    pi->align);
703 		if (pi->address == -1) {
704 			print_tag(pd->pc, pd->tag);
705 			printf("Failed to allocate PCI I/O space (%"
706 			    PRIu64 " req)\n", pi->size);
707 			return -1;
708 		}
709 		if (pd->ppb && pi->reg == 0) {
710 			pd->ppb->ioext = extent_create("pciconf", pi->address,
711 			    pi->address + pi->size, NULL, 0,
712 			    EX_NOWAIT);
713 			if (pd->ppb->ioext == NULL) {
714 				print_tag(pd->pc, pd->tag);
715 				printf("Failed to alloc I/O ext. for bus %d\n",
716 				    pd->ppb->busno);
717 				return -1;
718 			}
719 			continue;
720 		}
721 		if (!pb->io_32bit && pi->address > 0xFFFF) {
722 			pi->address = 0;
723 			pd->enable &= ~PCI_CONF_ENABLE_IO;
724 		} else {
725 			pd->enable |= PCI_CONF_ENABLE_IO;
726 		}
727 		if (pci_conf_debug) {
728 			print_tag(pd->pc, pd->tag);
729 			printf("Putting %" PRIu64 " I/O bytes @ %#" PRIx64
730 			    " (reg %x)\n", pi->size, pi->address, pi->reg);
731 		}
732 		pci_conf_write(pd->pc, pd->tag, pi->reg,
733 		    PCI_MAPREG_IO_ADDR(pi->address) | PCI_MAPREG_TYPE_IO);
734 	}
735 	return 0;
736 }
737 
738 static int
739 setup_memwins(pciconf_bus_t *pb)
740 {
741 	pciconf_win_t	*pm;
742 	pciconf_dev_t	*pd;
743 	pcireg_t	base;
744 	struct extent	*ex;
745 
746 	for (pm=pb->pcimemwin; pm < &pb->pcimemwin[pb->nmemwin] ; pm++) {
747 		if (pm->size == 0)
748 			continue;
749 
750 		pd = pm->dev;
751 		ex = (pm->prefetch) ? pb->pmemext : pb->memext;
752 		pm->address = pci_allocate_range(ex, pm->size, pm->align);
753 		if (pm->address == -1) {
754 			print_tag(pd->pc, pd->tag);
755 			printf(
756 			   "Failed to allocate PCI memory space (%" PRIu64
757 			   " req)\n", pm->size);
758 			return -1;
759 		}
760 		if (pd->ppb && pm->reg == 0) {
761 			ex = extent_create("pciconf", pm->address,
762 			    pm->address + pm->size, NULL, 0, EX_NOWAIT);
763 			if (ex == NULL) {
764 				print_tag(pd->pc, pd->tag);
765 				printf("Failed to alloc MEM ext. for bus %d\n",
766 				    pd->ppb->busno);
767 				return -1;
768 			}
769 			if (pm->prefetch) {
770 				pd->ppb->pmemext = ex;
771 			} else {
772 				pd->ppb->memext = ex;
773 			}
774 			continue;
775 		}
776 		if (pm->prefetch && !pb->pmem_64bit &&
777 		    pm->address > 0xFFFFFFFFULL) {
778 			pm->address = 0;
779 			pd->enable &= ~PCI_CONF_ENABLE_MEM;
780 		} else {
781 			pd->enable |= PCI_CONF_ENABLE_MEM;
782 		}
783 		if (pm->reg != PCI_MAPREG_ROM) {
784 			if (pci_conf_debug) {
785 				print_tag(pd->pc, pd->tag);
786 				printf(
787 				    "Putting %" PRIu64 " MEM bytes @ %#"
788 				    PRIx64 " (reg %x)\n", pm->size,
789 				    pm->address, pm->reg);
790 			}
791 			base = pci_conf_read(pd->pc, pd->tag, pm->reg);
792 			base = PCI_MAPREG_MEM_ADDR(pm->address) |
793 			    PCI_MAPREG_MEM_TYPE(base);
794 			pci_conf_write(pd->pc, pd->tag, pm->reg, base);
795 			if (PCI_MAPREG_MEM_TYPE(base) ==
796 			    PCI_MAPREG_MEM_TYPE_64BIT) {
797 				base = (pcireg_t)
798 				    (PCI_MAPREG_MEM64_ADDR(pm->address) >> 32);
799 				pci_conf_write(pd->pc, pd->tag, pm->reg + 4,
800 				    base);
801 			}
802 		}
803 	}
804 	for (pm=pb->pcimemwin; pm < &pb->pcimemwin[pb->nmemwin] ; pm++) {
805 		if (pm->reg == PCI_MAPREG_ROM && pm->address != -1) {
806 			pd = pm->dev;
807 			if (!(pd->enable & PCI_CONF_MAP_ROM))
808 				continue;
809 			if (pci_conf_debug) {
810 				print_tag(pd->pc, pd->tag);
811 				printf(
812 				    "Putting %" PRIu64 " ROM bytes @ %#"
813 				    PRIx64 " (reg %x)\n", pm->size,
814 				    pm->address, pm->reg);
815 			}
816 			base = (pcireg_t) pm->address;
817 			if (pd->enable & PCI_CONF_ENABLE_ROM)
818 				base |= PCI_MAPREG_ROM_ENABLE;
819 
820 			pci_conf_write(pd->pc, pd->tag, pm->reg, base);
821 		}
822 	}
823 	return 0;
824 }
825 
826 /*
827  * Configure I/O, memory, and prefetcable memory spaces, then make
828  * a call to configure_bus().
829  */
830 static int
831 configure_bridge(pciconf_dev_t *pd)
832 {
833 	unsigned long	io_base, io_limit, mem_base, mem_limit;
834 	pciconf_bus_t	*pb;
835 	pcireg_t	io, iohigh, mem, cmd;
836 	int		rv;
837 
838 	pb = pd->ppb;
839 	/* Configure I/O base & limit*/
840 	if (pb->ioext) {
841 		io_base = pb->ioext->ex_start;
842 		io_limit = pb->ioext->ex_end;
843 	} else {
844 		io_base  = 0x1000;	/* 4K */
845 		io_limit = 0x0000;
846 	}
847 	if (pb->io_32bit) {
848 		iohigh =
849 		    ((io_base >> 16) << PCI_BRIDGE_IOHIGH_BASE_SHIFT) |
850 		    ((io_limit >> 16) << PCI_BRIDGE_IOHIGH_LIMIT_SHIFT);
851 	} else {
852 		if (io_limit > 0xFFFF) {
853 			printf("Bus %d bridge does not support 32-bit I/O.  ",
854 			    pb->busno);
855 			printf("Disabling I/O accesses\n");
856 			io_base  = 0x1000;	/* 4K */
857 			io_limit = 0x0000;
858 		}
859 		iohigh = 0;
860 	}
861 	io = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_STATIO_REG) &
862 	    (PCI_BRIDGE_STATIO_STATUS_MASK << PCI_BRIDGE_STATIO_STATUS_SHIFT);
863 	io |= (((io_base >> 8) & PCI_BRIDGE_STATIO_IOBASE_MASK)
864 	    << PCI_BRIDGE_STATIO_IOBASE_SHIFT);
865 	io |= (((io_limit >> 8) & PCI_BRIDGE_STATIO_IOLIMIT_MASK)
866 	    << PCI_BRIDGE_STATIO_IOLIMIT_SHIFT);
867 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_STATIO_REG, io);
868 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_IOHIGH_REG, iohigh);
869 
870 	/* Configure mem base & limit */
871 	if (pb->memext) {
872 		mem_base = pb->memext->ex_start;
873 		mem_limit = pb->memext->ex_end;
874 	} else {
875 		mem_base  = 0x100000;	/* 1M */
876 		mem_limit = 0x000000;
877 	}
878 #if ULONG_MAX > 0xffffffff
879 	if (mem_limit > 0xFFFFFFFFULL) {
880 		printf("Bus %d bridge MEM range out of range.  ", pb->busno);
881 		printf("Disabling MEM accesses\n");
882 		mem_base  = 0x100000;	/* 1M */
883 		mem_limit = 0x000000;
884 	}
885 #endif
886 	mem = (((mem_base >> 20) & PCI_BRIDGE_MEMORY_BASE_MASK)
887 	    << PCI_BRIDGE_MEMORY_BASE_SHIFT);
888 	mem |= (((mem_limit >> 20) & PCI_BRIDGE_MEMORY_LIMIT_MASK)
889 	    << PCI_BRIDGE_MEMORY_LIMIT_SHIFT);
890 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_MEMORY_REG, mem);
891 
892 	/* Configure prefetchable mem base & limit */
893 	if (pb->pmemext) {
894 		mem_base = pb->pmemext->ex_start;
895 		mem_limit = pb->pmemext->ex_end;
896 	} else {
897 		mem_base  = 0x100000;	/* 1M */
898 		mem_limit = 0x000000;
899 	}
900 	mem = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG);
901 #if ULONG_MAX > 0xffffffff
902 	if (!PCI_BRIDGE_PREFETCHMEM_64BITS(mem) && mem_limit > 0xFFFFFFFFULL) {
903 		printf("Bus %d bridge does not support 64-bit PMEM.  ",
904 		    pb->busno);
905 		printf("Disabling prefetchable-MEM accesses\n");
906 		mem_base  = 0x100000;	/* 1M */
907 		mem_limit = 0x000000;
908 	}
909 #endif
910 	mem = (((mem_base >> 20) & PCI_BRIDGE_PREFETCHMEM_BASE_MASK)
911 	    << PCI_BRIDGE_PREFETCHMEM_BASE_SHIFT);
912 	mem |= (((mem_limit >> 20) & PCI_BRIDGE_PREFETCHMEM_LIMIT_MASK)
913 	    << PCI_BRIDGE_PREFETCHMEM_LIMIT_SHIFT);
914 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG, mem);
915 	/*
916 	 * XXX -- 64-bit systems need a lot more than just this...
917 	 */
918 	if (PCI_BRIDGE_PREFETCHMEM_64BITS(mem)) {
919 		mem_base  = (uint64_t) mem_base  >> 32;
920 		mem_limit = (uint64_t) mem_limit >> 32;
921 		pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHBASE32_REG,
922 		    mem_base & 0xffffffff);
923 		pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHLIMIT32_REG,
924 		    mem_limit & 0xffffffff);
925 	}
926 
927 	rv = configure_bus(pb);
928 
929 	if (pb->ioext)
930 		extent_destroy(pb->ioext);
931 	if (pb->memext)
932 		extent_destroy(pb->memext);
933 	if (pb->pmemext)
934 		extent_destroy(pb->pmemext);
935 	if (rv == 0) {
936 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_BRIDGE_CONTROL_REG);
937 		cmd &= PCI_BRIDGE_CONTROL_MASK;
938 		cmd |= (PCI_BRIDGE_CONTROL_PERE | PCI_BRIDGE_CONTROL_SERR)
939 		    << PCI_BRIDGE_CONTROL_SHIFT;
940 		if (pb->fast_b2b) {
941 			cmd |= PCI_BRIDGE_CONTROL_SECFASTB2B
942 			    << PCI_BRIDGE_CONTROL_SHIFT;
943 		}
944 		pci_conf_write(pd->pc, pd->tag, PCI_BRIDGE_CONTROL_REG, cmd);
945 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG);
946 		cmd |= PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE;
947 		pci_conf_write(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG, cmd);
948 	}
949 
950 	return rv;
951 }
952 
953 /*
954  * Calculate latency values, allocate I/O and MEM segments, then set them
955  * up.  If a PCI-PCI bridge is found, configure the bridge separately,
956  * which will cause a recursive call back here.
957  */
958 static int
959 configure_bus(pciconf_bus_t *pb)
960 {
961 	pciconf_dev_t	*pd;
962 	int		def_ltim, max_ltim, band, bus_mhz;
963 
964 	if (pb->ndevs == 0) {
965 		if (pci_conf_debug)
966 			printf("PCI bus %d - no devices\n", pb->busno);
967 		return (1);
968 	}
969 	bus_mhz = pb->freq_66 ? 66 : 33;
970 	max_ltim = pb->max_mingnt * bus_mhz / 4;	/* cvt to cycle count */
971 	band = 4000000;					/* 0.25us cycles/sec */
972 	if (band < pb->bandwidth_used) {
973 		printf("PCI bus %d: Warning: Total bandwidth exceeded!? (%d)\n",
974 		    pb->busno, pb->bandwidth_used);
975 		def_ltim = -1;
976 	} else {
977 		def_ltim = (band - pb->bandwidth_used) / pb->ndevs;
978 		if (def_ltim > pb->min_maxlat)
979 			def_ltim = pb->min_maxlat;
980 		def_ltim = def_ltim * bus_mhz / 4;
981 	}
982 	def_ltim = (def_ltim + 7) & ~7;
983 	max_ltim = (max_ltim + 7) & ~7;
984 
985 	pb->def_ltim = MIN( def_ltim, 255 );
986 	pb->max_ltim = MIN( MAX(max_ltim, def_ltim ), 255 );
987 
988 	/*
989 	 * Now we have what we need to initialize the devices.
990 	 * It would probably be better if we could allocate all of these
991 	 * for all busses at once, but "not right now".  First, get a list
992 	 * of free memory ranges from the m.d. system.
993 	 */
994 	if (setup_iowins(pb) || setup_memwins(pb)) {
995 		printf("PCI bus configuration failed: ");
996 		printf("unable to assign all I/O and memory ranges.");
997 		return -1;
998 	}
999 
1000 	/*
1001 	 * Configure the latency for the devices, and enable them.
1002 	 */
1003 	for (pd=pb->device ; pd < &pb->device[pb->ndevs] ; pd++) {
1004 		pcireg_t cmd, class, misc;
1005 		int	ltim;
1006 
1007 		if (pci_conf_debug) {
1008 			print_tag(pd->pc, pd->tag);
1009 			printf("Configuring device.\n");
1010 		}
1011 		class = pci_conf_read(pd->pc, pd->tag, PCI_CLASS_REG);
1012 		misc = pci_conf_read(pd->pc, pd->tag, PCI_BHLC_REG);
1013 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG);
1014 		if (pd->enable & PCI_CONF_ENABLE_PARITY)
1015 			cmd |= PCI_COMMAND_PARITY_ENABLE;
1016 		if (pd->enable & PCI_CONF_ENABLE_SERR)
1017 			cmd |= PCI_COMMAND_SERR_ENABLE;
1018 		if (pb->fast_b2b)
1019 			cmd |= PCI_COMMAND_BACKTOBACK_ENABLE;
1020 		if (PCI_CLASS(class) != PCI_CLASS_BRIDGE ||
1021 		    PCI_SUBCLASS(class) != PCI_SUBCLASS_BRIDGE_PCI) {
1022 			if (pd->enable & PCI_CONF_ENABLE_IO)
1023 				cmd |= PCI_COMMAND_IO_ENABLE;
1024 			if (pd->enable & PCI_CONF_ENABLE_MEM)
1025 				cmd |= PCI_COMMAND_MEM_ENABLE;
1026 			if (pd->enable & PCI_CONF_ENABLE_BM)
1027 				cmd |= PCI_COMMAND_MASTER_ENABLE;
1028 			ltim = pd->min_gnt * bus_mhz / 4;
1029 			ltim = MIN (MAX (pb->def_ltim, ltim), pb->max_ltim);
1030 		} else {
1031 			cmd |= PCI_COMMAND_MASTER_ENABLE;
1032 			ltim = MIN (pb->def_ltim, pb->max_ltim);
1033 		}
1034 		if ((pd->enable &
1035 		    (PCI_CONF_ENABLE_MEM|PCI_CONF_ENABLE_IO)) == 0) {
1036 			print_tag(pd->pc, pd->tag);
1037 			printf("Disabled due to lack of resources.\n");
1038 			cmd &= ~(PCI_COMMAND_MASTER_ENABLE |
1039 			    PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
1040 		}
1041 		pci_conf_write(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG, cmd);
1042 
1043 		misc &= ~((PCI_LATTIMER_MASK << PCI_LATTIMER_SHIFT) |
1044 		    (PCI_CACHELINE_MASK << PCI_CACHELINE_SHIFT));
1045 		misc |= (ltim & PCI_LATTIMER_MASK) << PCI_LATTIMER_SHIFT;
1046 		misc |= ((pb->cacheline_size >> 2) & PCI_CACHELINE_MASK) <<
1047 		    PCI_CACHELINE_SHIFT;
1048 		pci_conf_write(pd->pc, pd->tag, PCI_BHLC_REG, misc);
1049 
1050 		if (pd->ppb) {
1051 			if (configure_bridge(pd) < 0)
1052 				return -1;
1053 			continue;
1054 		}
1055 	}
1056 
1057 	if (pci_conf_debug) {
1058 		printf("PCI bus %d configured\n", pb->busno);
1059 	}
1060 
1061 	return 0;
1062 }
1063 
1064 /*
1065  * Let's configure the PCI bus.
1066  * This consists of basically scanning for all existing devices,
1067  * identifying their needs, and then making another pass over them
1068  * to set:
1069  *	1. I/O addresses
1070  *	2. Memory addresses (Prefetchable and not)
1071  *	3. PCI command register
1072  *	4. The latency part of the PCI BHLC (BIST (Built-In Self Test),
1073  *	    Header type, Latency timer, Cache line size) register
1074  *
1075  * The command register is set to enable fast back-to-back transactions
1076  * if the host bridge says it can handle it.  We also configure
1077  * Master Enable, SERR enable, parity enable, and (if this is not a
1078  * PCI-PCI bridge) the I/O and Memory spaces.  Apparently some devices
1079  * will not report some I/O space.
1080  *
1081  * The latency is computed to be a "fair share" of the bus bandwidth.
1082  * The bus bandwidth variable is initialized to the number of PCI cycles
1083  * in one second.  The number of cycles taken for one transaction by each
1084  * device (MAX_LAT + MIN_GNT) is then subtracted from the bandwidth.
1085  * Care is taken to ensure that the latency timer won't be set such that
1086  * it would exceed the critical time for any device.
1087  *
1088  * This is complicated somewhat due to the presence of bridges.  PCI-PCI
1089  * bridges are probed and configured recursively.
1090  */
1091 int
1092 pci_configure_bus(pci_chipset_tag_t pc, struct extent *ioext,
1093     struct extent *memext, struct extent *pmemext, int firstbus,
1094     int cacheline_size)
1095 {
1096 	pciconf_bus_t	*pb;
1097 	int		rv;
1098 
1099 	pb = kmem_zalloc(sizeof (pciconf_bus_t), KM_NOSLEEP);
1100 	pb->busno = firstbus;
1101 	pb->next_busno = pb->busno + 1;
1102 	pb->last_busno = 255;
1103 	pb->cacheline_size = cacheline_size;
1104 	pb->parent_bus = NULL;
1105 	pb->swiz = 0;
1106 	pb->io_32bit = 1;
1107 	pb->pmem_64bit = 0;
1108 	pb->ioext = ioext;
1109 	pb->memext = memext;
1110 	if (pmemext == NULL) {
1111 		pb->pmemext = memext;
1112 	} else {
1113 		pb->pmemext = pmemext;
1114 	}
1115 	pb->pc = pc;
1116 	pb->io_total = pb->mem_total = pb->pmem_total = 0;
1117 
1118 	rv = probe_bus(pb);
1119 	pb->last_busno = pb->next_busno-1;
1120 	if (rv == 0) {
1121 		rv = configure_bus(pb);
1122 	}
1123 
1124 	/*
1125 	 * All done!
1126 	 */
1127 	kmem_free(pb, sizeof(*pb));
1128 	return rv;
1129 }
1130