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pciconf.c revision 1.16
      1 /*	$NetBSD: pciconf.c,v 1.16 2002/06/27 00:59:21 briggs 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 1.16 2002/06/27 00:59:21 briggs 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 
     78 #include <dev/pci/pcivar.h>
     79 #include <dev/pci/pciconf.h>
     80 #include <dev/pci/pcidevs.h>
     81 
     82 int pci_conf_debug = 0;
     83 
     84 #if !defined(MIN)
     85 #define	MIN(a,b) (((a)<(b))?(a):(b))
     86 #define	MAX(a,b) (((a)>(b))?(a):(b))
     87 #endif
     88 
     89 /* per-bus constants. */
     90 #define MAX_CONF_DEV	32			/* Arbitrary */
     91 #define MAX_CONF_MEM	(3 * MAX_CONF_DEV)	/* Avg. 3 per device -- Arb. */
     92 #define MAX_CONF_IO	(3 * MAX_CONF_DEV)	/* Avg. 1 per device -- Arb. */
     93 
     94 #define PCI_BUSNO_SPACING	(1 << 5)
     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		busno_spacing;
    123 	int		max_mingnt;
    124 	int		min_maxlat;
    125 	int		cacheline_size;
    126 	int		prefetch;
    127 	int		fast_b2b;
    128 	int		freq_66;
    129 	int		def_ltim;
    130 	int		max_ltim;
    131 	int		bandwidth_used;
    132 	int		swiz;
    133 	int		io_32bit;
    134 	int		pmem_64bit;
    135 
    136 	int		ndevs;
    137 	pciconf_dev_t	device[MAX_CONF_DEV];
    138 
    139 	/* These should be sorted in order of decreasing size */
    140 	int		nmemwin;
    141 	pciconf_win_t	pcimemwin[MAX_CONF_MEM];
    142 	int		niowin;
    143 	pciconf_win_t	pciiowin[MAX_CONF_IO];
    144 
    145 	bus_size_t	io_total;
    146 	bus_size_t	mem_total;
    147 	bus_size_t	pmem_total;
    148 
    149 	struct extent	*ioext;
    150 	struct extent	*memext;
    151 	struct extent	*pmemext;
    152 
    153 	pci_chipset_tag_t	pc;
    154 	struct _s_pciconf_bus_t *parent_bus;
    155 } pciconf_bus_t;
    156 
    157 static int	probe_bus(pciconf_bus_t *);
    158 static void	alloc_busno(pciconf_bus_t *, pciconf_bus_t *);
    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, maxdevs;
    215 #ifdef __PCI_BUS_DEVORDER
    216 	char devs[32];
    217 	int  i;
    218 #endif
    219 
    220 	maxdevs = pci_bus_maxdevs(pb->pc, pb->busno);
    221 	pb->ndevs = 0;
    222 	pb->niowin = 0;
    223 	pb->nmemwin = 0;
    224 	pb->freq_66 = 1;
    225 	pb->fast_b2b = 1;
    226 	pb->prefetch = 1;
    227 	pb->max_mingnt = 0;	/* we are looking for the maximum */
    228 	pb->min_maxlat = 0x100;	/* we are looking for the minimum */
    229 	pb->bandwidth_used = 0;
    230 
    231 #ifdef __PCI_BUS_DEVORDER
    232 	pci_bus_devorder(pb->pc, pb->busno, devs);
    233 	for (i=0; (device=devs[i]) < 32 && device >= 0; i++) {
    234 #else
    235 	for (device=0; device < maxdevs; device++) {
    236 #endif
    237 		pcitag_t tag;
    238 		pcireg_t id, bhlcr;
    239 		int function, nfunction;
    240 		int confmode;
    241 
    242 		tag = pci_make_tag(pb->pc, pb->busno, device, 0);
    243 		if (pci_conf_debug) {
    244 			print_tag(pb->pc, tag);
    245 		}
    246 		id = pci_conf_read(pb->pc, tag, PCI_ID_REG);
    247 
    248 		if (pci_conf_debug) {
    249 			printf("id=%x: Vendor=%x, Product=%x\n",
    250 			    id, PCI_VENDOR(id),PCI_PRODUCT(id));
    251 		}
    252 		/* Invalid vendor ID value? */
    253 		if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
    254 			continue;
    255 
    256 		bhlcr = pci_conf_read(pb->pc, tag, PCI_BHLC_REG);
    257 		nfunction = PCI_HDRTYPE_MULTIFN(bhlcr) ? 8 : 1;
    258 		for (function = 0 ; function < nfunction ; function++) {
    259 			tag = pci_make_tag(pb->pc, pb->busno, device, function);
    260 			id = pci_conf_read(pb->pc, tag, PCI_ID_REG);
    261 			if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
    262 				continue;
    263 			if (pb->ndevs+1 < MAX_CONF_DEV) {
    264 				if (pci_conf_debug) {
    265 					print_tag(pb->pc, tag);
    266 					printf("Found dev 0x%04x 0x%04x -- "
    267 					    "really probing.\n",
    268 					PCI_VENDOR(id), PCI_PRODUCT(id));
    269 				}
    270 #ifdef __HAVE_PCI_CONF_HOOK
    271 				confmode = pci_conf_hook(pb->pc, pb->busno,
    272 				    device, function, id);
    273 				if (confmode == 0)
    274 					continue;
    275 #else
    276 				/*
    277 				 * Don't enable expansion ROMS -- some cards
    278 				 * share address decoders between the EXPROM
    279 				 * and PCI memory space, and enabling the ROM
    280 				 * when not needed will cause all sorts of
    281 				 * lossage.
    282 				 */
    283 				confmode = PCI_CONF_ALL & ~PCI_CONF_MAP_ROM;
    284 #endif
    285 				if (pci_do_device_query(pb, tag, device,
    286 				    function, confmode))
    287 					return -1;
    288 				pb->ndevs++;
    289 			}
    290 		}
    291 	}
    292 	return 0;
    293 }
    294 
    295 static void
    296 alloc_busno(pciconf_bus_t *parent, pciconf_bus_t *pb)
    297 {
    298 	pb->busno = parent->next_busno;
    299 	if (parent->next_busno + parent->busno_spacing > parent->last_busno)
    300 		panic("Too many PCI busses on bus %d", parent->busno);
    301 	parent->next_busno = parent->next_busno + parent->busno_spacing;
    302 	pb->next_busno = pb->busno+1;
    303 	pb->busno_spacing = parent->busno_spacing >> 1;
    304 	if (!pb->busno_spacing)
    305 		panic("PCI busses nested too deep.");
    306 	pb->last_busno = parent->next_busno - 1;
    307 }
    308 
    309 static pciconf_bus_t *
    310 query_bus(pciconf_bus_t *parent, pciconf_dev_t *pd, int dev)
    311 {
    312 	pciconf_bus_t	*pb;
    313 	pcireg_t	busreg, io, pmem;
    314 	pciconf_win_t	*pi, *pm;
    315 
    316 	pb = malloc (sizeof (pciconf_bus_t), M_DEVBUF, M_NOWAIT);
    317 	if (!pb)
    318 		panic("Unable to allocate memory for PCI configuration.");
    319 
    320 	pb->cacheline_size = parent->cacheline_size;
    321 	pb->parent_bus = parent;
    322 	alloc_busno(parent, pb);
    323 	if (pci_conf_debug)
    324 		printf("PCI bus bridge covers busses %d-%d\n",
    325 			pb->busno, pb->last_busno);
    326 
    327 	busreg  =  parent->busno << PCI_BRIDGE_BUS_PRIMARY_SHIFT;
    328 	busreg |=      pb->busno << PCI_BRIDGE_BUS_SECONDARY_SHIFT;
    329 	busreg |= pb->last_busno << PCI_BRIDGE_BUS_SUBORDINATE_SHIFT;
    330 	pci_conf_write(parent->pc, pd->tag, PCI_BRIDGE_BUS_REG, busreg);
    331 
    332 	pb->swiz = parent->swiz + dev;
    333 
    334 	pb->ioext = NULL;
    335 	pb->memext = NULL;
    336 	pb->pmemext = NULL;
    337 	pb->pc = parent->pc;
    338 	pb->io_total = pb->mem_total = pb->pmem_total = 0;
    339 
    340 	pb->io_32bit = 0;
    341 	if (parent->io_32bit) {
    342 		io = pci_conf_read(parent->pc, pd->tag, PCI_BRIDGE_STATIO_REG);
    343 		if (PCI_BRIDGE_IO_32BITS(io)) {
    344 			pb->io_32bit = 1;
    345 		}
    346 	}
    347 
    348 	pb->pmem_64bit = 0;
    349 	if (parent->pmem_64bit) {
    350 		pmem = pci_conf_read(parent->pc, pd->tag,
    351 		    PCI_BRIDGE_PREFETCHMEM_REG);
    352 		if (PCI_BRIDGE_PREFETCHMEM_64BITS(pmem)) {
    353 			pb->pmem_64bit = 1;
    354 		}
    355 	}
    356 
    357 	if (probe_bus(pb)) {
    358 		printf("Failed to probe bus %d\n", pb->busno);
    359 		goto err;
    360 	}
    361 
    362 	if (pb->io_total > 0) {
    363 		if (parent->niowin >= MAX_CONF_IO) {
    364 			printf("pciconf: too many I/O windows\n");
    365 			goto err;
    366 		}
    367 		pb->io_total |= 0xfff;	/* Round up */
    368 		pi = get_io_desc(parent, pb->io_total);
    369 		pi->dev = pd;
    370 		pi->reg = 0;
    371 		pi->size = pb->io_total;
    372 		pi->align = 0x1000;	/* 4K alignment */
    373 		pi->prefetch = 0;
    374 		parent->niowin++;
    375 		parent->io_total += pb->io_total;
    376 	}
    377 
    378 	if (pb->mem_total > 0) {
    379 		if (parent->nmemwin >= MAX_CONF_MEM) {
    380 			printf("pciconf: too many MEM windows\n");
    381 			goto err;
    382 		}
    383 		pb->mem_total |= 0xfffff;	/* Round up */
    384 		pm = get_mem_desc(parent, pb->mem_total);
    385 		pm->dev = pd;
    386 		pm->reg = 0;
    387 		pm->size = pb->mem_total;
    388 		pm->align = 0x100000;	/* 1M alignment */
    389 		pm->prefetch = 0;
    390 		parent->nmemwin++;
    391 		parent->mem_total += pb->mem_total;
    392 	}
    393 
    394 	if (pb->pmem_total > 0) {
    395 		if (parent->nmemwin >= MAX_CONF_MEM) {
    396 			printf("pciconf: too many MEM windows\n");
    397 			goto err;
    398 		}
    399 		pb->pmem_total |= 0xfffff;	/* Round up */
    400 		pm = get_mem_desc(parent, pb->pmem_total);
    401 		pm->dev = pd;
    402 		pm->reg = 0;
    403 		pm->size = pb->pmem_total;
    404 		pm->align = 0x100000;		/* 1M alignment */
    405 		pm->prefetch = 1;
    406 		parent->nmemwin++;
    407 		parent->pmem_total += pb->pmem_total;
    408 	}
    409 
    410 	return pb;
    411 err:
    412 	free(pb, M_DEVBUF);
    413 	return NULL;
    414 }
    415 
    416 static int
    417 pci_do_device_query(pciconf_bus_t *pb, pcitag_t tag, int dev, int func, int mode)
    418 {
    419 	pciconf_dev_t	*pd;
    420 	pciconf_win_t	*pi, *pm;
    421 	pcireg_t	class, cmd, icr, bar, mask, bar64, mask64;
    422 	u_int64_t	size;
    423 	int		br, width;
    424 
    425 	pd = &pb->device[pb->ndevs];
    426 	pd->pc = pb->pc;
    427 	pd->tag = tag;
    428 	pd->ppb = NULL;
    429 	pd->enable = mode;
    430 
    431 	class = pci_conf_read(pb->pc, tag, PCI_CLASS_REG);
    432 
    433 	cmd = pci_conf_read(pb->pc, tag, PCI_COMMAND_STATUS_REG);
    434 
    435 	if (PCI_CLASS(class) != PCI_CLASS_BRIDGE) {
    436 		cmd &= ~(PCI_COMMAND_MASTER_ENABLE |
    437 		    PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
    438 		pci_conf_write(pb->pc, tag, PCI_COMMAND_STATUS_REG, cmd);
    439 	} else if (pci_conf_debug) {
    440 		print_tag(pb->pc, tag);
    441 		printf("device is a bridge; not clearing enables\n");
    442 	}
    443 
    444 	if ((cmd & PCI_STATUS_BACKTOBACK_SUPPORT) == 0)
    445 		pb->fast_b2b = 0;
    446 
    447 	if ((cmd & PCI_STATUS_66MHZ_SUPPORT) == 0)
    448 		pb->freq_66 = 0;
    449 
    450 	if (   (PCI_CLASS(class) == PCI_CLASS_BRIDGE)
    451 	    && (PCI_SUBCLASS(class) == PCI_SUBCLASS_BRIDGE_PCI)) {
    452 		pd->ppb = query_bus(pb, pd, dev);
    453 		if (pd->ppb == NULL)
    454 			return -1;
    455 		return 0;
    456 	}
    457 
    458 	icr = pci_conf_read(pb->pc, tag, PCI_INTERRUPT_REG);
    459 	pd->ipin = PCI_INTERRUPT_PIN(icr);
    460 	pd->iline = PCI_INTERRUPT_LINE(icr);
    461 	pd->min_gnt = PCI_MIN_GNT(icr);
    462 	pd->max_lat = PCI_MAX_LAT(icr);
    463 	if (pd->iline || pd->ipin) {
    464 		pci_conf_interrupt(pb->pc, pb->busno, dev, pd->ipin, pb->swiz,
    465 		    &pd->iline);
    466 		icr &= ~(PCI_INTERRUPT_LINE_MASK << PCI_INTERRUPT_LINE_SHIFT);
    467 		icr |= (pd->iline << PCI_INTERRUPT_LINE_SHIFT);
    468 		pci_conf_write(pb->pc, tag, PCI_INTERRUPT_REG, icr);
    469 	}
    470 
    471 	if (pd->min_gnt != 0 || pd->max_lat != 0) {
    472 		if (pd->min_gnt != 0 && pd->min_gnt > pb->max_mingnt)
    473 			pb->max_mingnt = pd->min_gnt;
    474 
    475 		if (pd->max_lat != 0 && pd->max_lat < pb->min_maxlat)
    476 			pb->min_maxlat = pd->max_lat;
    477 
    478 		pb->bandwidth_used += pd->min_gnt * 4000000 /
    479 				(pd->min_gnt + pd->max_lat);
    480 	}
    481 
    482 	width = 4;
    483 	for (br = PCI_MAPREG_START; br < PCI_MAPREG_END; br += width) {
    484 #if 0
    485 /* XXX Should only ignore if IDE not in legacy mode? */
    486 		if (PCI_CLASS(class) == PCI_CLASS_MASS_STORAGE &&
    487 		    PCI_SUBCLASS(class) == PCI_SUBCLASS_MASS_STORAGE_IDE) {
    488 			break;
    489 		}
    490 #endif
    491 		bar = pci_conf_read(pb->pc, tag, br);
    492 		pci_conf_write(pb->pc, tag, br, 0xffffffff);
    493 		mask = pci_conf_read(pb->pc, tag, br);
    494 		pci_conf_write(pb->pc, tag, br, bar);
    495 		width = 4;
    496 
    497 		if (   (mode & PCI_CONF_MAP_IO)
    498 		    && (PCI_MAPREG_TYPE(mask) == PCI_MAPREG_TYPE_IO)) {
    499 			/*
    500 			 * Upper 16 bits must be one.  Devices may hardwire
    501 			 * them to zero, though, per PCI 2.2, 6.2.5.1, p 203.
    502 			 */
    503 			mask |= 0xffff0000;
    504 
    505 			size = PCI_MAPREG_IO_SIZE(mask);
    506 			if (size == 0) {
    507 				if (pci_conf_debug) {
    508 					print_tag(pb->pc, tag);
    509 					printf("I/O BAR 0x%x is void\n", br);
    510 				}
    511 				continue;
    512 			}
    513 
    514 			if (pb->niowin >= MAX_CONF_IO) {
    515 				printf("pciconf: too many I/O windows\n");
    516 				return -1;
    517 			}
    518 
    519 			pi = get_io_desc(pb, size);
    520 			pi->dev = pd;
    521 			pi->reg = br;
    522 			pi->size = (u_int64_t) size;
    523 			pi->align = 4;
    524 			pi->prefetch = 0;
    525 			if (pci_conf_debug) {
    526 				print_tag(pb->pc, tag);
    527 				printf("Register 0x%x, I/O size %llu\n",
    528 				    br, pi->size);
    529 			}
    530 			pb->niowin++;
    531 			pb->io_total += size;
    532 		} else if ((mode & PCI_CONF_MAP_MEM)
    533 			   && (PCI_MAPREG_TYPE(mask) == PCI_MAPREG_TYPE_MEM)) {
    534 			switch (PCI_MAPREG_MEM_TYPE(mask)) {
    535 			case PCI_MAPREG_MEM_TYPE_32BIT:
    536 			case PCI_MAPREG_MEM_TYPE_32BIT_1M:
    537 				size = (u_int64_t) PCI_MAPREG_MEM_SIZE(mask);
    538 				break;
    539 			case PCI_MAPREG_MEM_TYPE_64BIT:
    540 				bar64 = pci_conf_read(pb->pc, tag, br + 4);
    541 				pci_conf_write(pb->pc, tag, br + 4, 0xffffffff);
    542 				mask64 = pci_conf_read(pb->pc, tag, br + 4);
    543 				pci_conf_write(pb->pc, tag, br + 4, bar64);
    544 				size = (u_int64_t) PCI_MAPREG_MEM64_SIZE(
    545 				      (((u_int64_t) mask64) << 32) | mask);
    546 				width = 8;
    547 				break;
    548 			default:
    549 				print_tag(pb->pc, tag);
    550 				printf("reserved mapping type 0x%x\n",
    551 					PCI_MAPREG_MEM_TYPE(mask));
    552 				continue;
    553 			}
    554 
    555 			if (size == 0) {
    556 				if (pci_conf_debug) {
    557 					print_tag(pb->pc, tag);
    558 					printf("MEM%d BAR 0x%x is void\n",
    559 					    PCI_MAPREG_MEM_TYPE(mask) ==
    560 						PCI_MAPREG_MEM_TYPE_64BIT ?
    561 						64 : 32, br);
    562 				}
    563 				continue;
    564 			} else {
    565 				if (pci_conf_debug) {
    566 					print_tag(pb->pc, tag);
    567 					printf("MEM%d BAR 0x%x has size %lx\n",
    568 					    PCI_MAPREG_MEM_TYPE(mask) ==
    569 						PCI_MAPREG_MEM_TYPE_64BIT ?
    570 						64 : 32, br, (unsigned long)size);
    571 				}
    572 			}
    573 
    574 			if (pb->nmemwin >= MAX_CONF_MEM) {
    575 				printf("pciconf: too many memory windows\n");
    576 				return -1;
    577 			}
    578 
    579 			pm = get_mem_desc(pb, size);
    580 			pm->dev = pd;
    581 			pm->reg = br;
    582 			pm->size = size;
    583 			pm->align = 4;
    584 			pm->prefetch = PCI_MAPREG_MEM_PREFETCHABLE(mask);
    585 			if (pci_conf_debug) {
    586 				print_tag(pb->pc, tag);
    587 				printf("Register 0x%x, memory size %llu\n",
    588 				    br, pm->size);
    589 			}
    590 			pb->nmemwin++;
    591 			if (pm->prefetch) {
    592 				pb->pmem_total += size;
    593 			} else {
    594 				pb->mem_total += size;
    595 			}
    596 		}
    597 	}
    598 
    599 	if (mode & PCI_CONF_MAP_ROM) {
    600 		bar = pci_conf_read(pb->pc, tag, PCI_MAPREG_ROM);
    601 		pci_conf_write(pb->pc, tag, PCI_MAPREG_ROM, 0xfffffffe);
    602 		mask = pci_conf_read(pb->pc, tag, PCI_MAPREG_ROM);
    603 		pci_conf_write(pb->pc, tag, PCI_MAPREG_ROM, bar);
    604 
    605 		if (mask != 0 && mask != 0xffffffff) {
    606 			if (pb->nmemwin >= MAX_CONF_MEM) {
    607 				printf("pciconf: too many memory windows\n");
    608 				return -1;
    609 			}
    610 			size = (u_int64_t) PCI_MAPREG_MEM_SIZE(mask);
    611 
    612 			pm = get_mem_desc(pb, size);
    613 			pm->dev = pd;
    614 			pm->reg = PCI_MAPREG_ROM;
    615 			pm->size = size;
    616 			pm->align = 4;
    617 			pm->prefetch = 1;
    618 			if (pci_conf_debug) {
    619 				print_tag(pb->pc, tag);
    620 				printf("Expansion ROM memory size %llu\n", pm->size);
    621 			}
    622 			pb->nmemwin++;
    623 			pb->pmem_total += size;
    624 		}
    625 	} else {
    626 		/* Ensure ROM is disabled */
    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,
    631 		    bar & ~PCI_MAPREG_ROM_ENABLE);
    632 	}
    633 
    634 	return 0;
    635 }
    636 
    637 /************************************************************************/
    638 /************************************************************************/
    639 /********************   Bus configuration routines   ********************/
    640 /************************************************************************/
    641 /************************************************************************/
    642 static u_int64_t
    643 pci_allocate_range(struct extent *ex, u_int64_t amt, int align)
    644 {
    645 	int	r;
    646 	u_long	addr;
    647 
    648 	r = extent_alloc(ex, amt, align, 0, EX_NOWAIT, &addr);
    649 	if (r) {
    650 		addr = (u_long) -1;
    651 		printf("extent_alloc(%p, %llu, %d) returned %d\n",
    652 		    ex, amt, align, r);
    653 		extent_print(ex);
    654 	}
    655 	return (pcireg_t) addr;
    656 }
    657 
    658 static int
    659 setup_iowins(pciconf_bus_t *pb)
    660 {
    661 	pciconf_win_t	*pi;
    662 	pciconf_dev_t	*pd;
    663 
    664 	for (pi=pb->pciiowin; pi < &pb->pciiowin[pb->niowin] ; pi++) {
    665 		if (pi->size == 0)
    666 			continue;
    667 
    668 		pd = pi->dev;
    669 		pi->address = pci_allocate_range(pb->ioext, pi->size,
    670 		    pi->align);
    671 		if (pi->address == -1) {
    672 			print_tag(pd->pc, pd->tag);
    673 			printf("Failed to allocate PCI I/O space (%llu req)\n",
    674 			   pi->size);
    675 			return -1;
    676 		}
    677 		if (!pb->io_32bit && pi->address > 0xFFFF) {
    678 			pi->address = 0;
    679 			pd->enable = 0;
    680 		}
    681 		if (pd->ppb && pi->reg == 0) {
    682 			pd->ppb->ioext = extent_create("pciconf", pi->address,
    683 			    pi->address + pi->size, M_DEVBUF, NULL, 0,
    684 			    EX_NOWAIT);
    685 			if (pd->ppb->ioext == NULL) {
    686 				print_tag(pd->pc, pd->tag);
    687 				printf("Failed to alloc I/O ext. for bus %d\n",
    688 				    pd->ppb->busno);
    689 				return -1;
    690 			}
    691 			continue;
    692 		}
    693 		pd->enable |= PCI_CONF_ENABLE_IO;
    694 		if (pci_conf_debug) {
    695 			print_tag(pd->pc, pd->tag);
    696 			printf("Putting %llu I/O bytes @ %#llx (reg %x)\n",
    697 			    pi->size, pi->address, pi->reg);
    698 		}
    699 		pci_conf_write(pd->pc, pd->tag, pi->reg,
    700 		    PCI_MAPREG_IO_ADDR(pi->address) | PCI_MAPREG_TYPE_IO);
    701 	}
    702 	return 0;
    703 }
    704 
    705 static int
    706 setup_memwins(pciconf_bus_t *pb)
    707 {
    708 	pciconf_win_t	*pm;
    709 	pciconf_dev_t	*pd;
    710 	pcireg_t	base;
    711 	struct extent	*ex;
    712 
    713 	for (pm=pb->pcimemwin; pm < &pb->pcimemwin[pb->nmemwin] ; pm++) {
    714 		if (pm->size == 0)
    715 			continue;
    716 
    717 		pd = pm->dev;
    718 		ex = (pm->prefetch) ? pb->pmemext : pb->memext;
    719 		pm->address = pci_allocate_range(ex, pm->size, pm->align);
    720 		if (pm->address == -1) {
    721 			print_tag(pd->pc, pd->tag);
    722 			printf(
    723 			   "Failed to allocate PCI memory space (%llu req)\n",
    724 			   pm->size);
    725 			return -1;
    726 		}
    727 		if (pd->ppb && pm->reg == 0) {
    728 			ex = extent_create("pciconf", pm->address,
    729 			    pm->address + pm->size, M_DEVBUF, NULL, 0,
    730 			    EX_NOWAIT);
    731 			if (ex == NULL) {
    732 				print_tag(pd->pc, pd->tag);
    733 				printf("Failed to alloc MEM ext. for bus %d\n",
    734 				    pd->ppb->busno);
    735 				return -1;
    736 			}
    737 			if (pm->prefetch) {
    738 				pd->ppb->pmemext = ex;
    739 			} else {
    740 				pd->ppb->memext = ex;
    741 			}
    742 			continue;
    743 		}
    744 		if (pm->prefetch && !pb->pmem_64bit &&
    745 		    pm->address > 0xFFFFFFFFULL) {
    746 			pm->address = 0;
    747 			pd->enable = 0;
    748 		} else {
    749 			pd->enable |= PCI_CONF_ENABLE_MEM;
    750 		}
    751 		if (pm->reg != PCI_MAPREG_ROM) {
    752 			if (pci_conf_debug) {
    753 				print_tag(pd->pc, pd->tag);
    754 				printf(
    755 				    "Putting %llu MEM bytes @ %#llx (reg %x)\n",
    756 				     pm->size, pm->address, pm->reg);
    757 			}
    758 			base = pci_conf_read(pd->pc, pd->tag, pm->reg);
    759 			base = PCI_MAPREG_MEM_ADDR(pm->address) |
    760 			    PCI_MAPREG_MEM_TYPE(base);
    761 			pci_conf_write(pd->pc, pd->tag, pm->reg, base);
    762 			if (PCI_MAPREG_MEM_TYPE(base) ==
    763 			    PCI_MAPREG_MEM_TYPE_64BIT) {
    764 				base = (pcireg_t)
    765 				    (PCI_MAPREG_MEM64_ADDR(pm->address) >> 32);
    766 				pci_conf_write(pd->pc, pd->tag, pm->reg + 4,
    767 				    base);
    768 			}
    769 		}
    770 	}
    771 	for (pm=pb->pcimemwin; pm < &pb->pcimemwin[pb->nmemwin] ; pm++) {
    772 		if (pm->reg == PCI_MAPREG_ROM && pm->address != -1) {
    773 			pd = pm->dev;
    774 			if (pci_conf_debug) {
    775 				print_tag(pd->pc, pd->tag);
    776 				printf(
    777 				    "Putting %llu ROM bytes @ %#llx (reg %x)\n",
    778 				    pm->size, pm->address, pm->reg);
    779 			}
    780 			base = (pcireg_t) (pm->address | PCI_MAPREG_ROM_ENABLE);
    781 			pci_conf_write(pd->pc, pd->tag, pm->reg, base);
    782 		}
    783 	}
    784 	return 0;
    785 }
    786 
    787 /*
    788  * Configure I/O, memory, and prefetcable memory spaces, then make
    789  * a call to configure_bus().
    790  */
    791 static int
    792 configure_bridge(pciconf_dev_t *pd)
    793 {
    794 	unsigned long	io_base, io_limit, mem_base, mem_limit;
    795 	pciconf_bus_t	*pb;
    796 	pcireg_t	io, iohigh, mem, cmd;
    797 	int		rv;
    798 
    799 	pb = pd->ppb;
    800 	/* Configure I/O base & limit*/
    801 	if (pb->ioext) {
    802 		io_base = pb->ioext->ex_start;
    803 		io_limit = pb->ioext->ex_end;
    804 	} else {
    805 		io_base  = 0x1000;	/* 4K */
    806 		io_limit = 0x0000;
    807 	}
    808 	if (pb->io_32bit) {
    809 		iohigh =
    810 		    ((io_base >> 16) << PCI_BRIDGE_IOHIGH_BASE_SHIFT) |
    811 		    ((io_limit >> 16) << PCI_BRIDGE_IOHIGH_LIMIT_SHIFT);
    812 	} else {
    813 		if (io_limit > 0xFFFF) {
    814 			printf("Bus %d bridge does not support 32-bit I/O.  ",
    815 			    pb->busno);
    816 			printf("Disabling I/O accesses\n");
    817 			io_base  = 0x1000;	/* 4K */
    818 			io_limit = 0x0000;
    819 		}
    820 		iohigh = 0;
    821 	}
    822 	io = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_STATIO_REG) &
    823 	    (PCI_BRIDGE_STATIO_STATUS_MASK << PCI_BRIDGE_STATIO_STATUS_SHIFT);
    824 	io |= (((io_base >> 8) & PCI_BRIDGE_STATIO_IOBASE_MASK)
    825 	    << PCI_BRIDGE_STATIO_IOBASE_SHIFT);
    826 	io |= (((io_limit >> 8) & PCI_BRIDGE_STATIO_IOLIMIT_MASK)
    827 	    << PCI_BRIDGE_STATIO_IOLIMIT_SHIFT);
    828 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_STATIO_REG, io);
    829 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_IOHIGH_REG, iohigh);
    830 
    831 	/* Configure mem base & limit */
    832 	if (pb->memext) {
    833 		mem_base = pb->memext->ex_start;
    834 		mem_limit = pb->memext->ex_end;
    835 	} else {
    836 		mem_base  = 0x100000;	/* 1M */
    837 		mem_limit = 0x000000;
    838 	}
    839 	if (mem_limit > 0xFFFFFFFFULL) {
    840 		printf("Bus %d bridge MEM range out of range.  ", pb->busno);
    841 		printf("Disabling MEM accesses\n");
    842 		mem_base  = 0x100000;	/* 1M */
    843 		mem_limit = 0x000000;
    844 	}
    845 	mem = (((mem_base >> 20) & PCI_BRIDGE_MEMORY_BASE_MASK)
    846 	    << PCI_BRIDGE_MEMORY_BASE_SHIFT);
    847 	mem |= (((mem_limit >> 20) & PCI_BRIDGE_MEMORY_LIMIT_MASK)
    848 	    << PCI_BRIDGE_MEMORY_LIMIT_SHIFT);
    849 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_MEMORY_REG, mem);
    850 
    851 	/* Configure prefetchable mem base & limit */
    852 	if (pb->pmemext) {
    853 		mem_base = pb->pmemext->ex_start;
    854 		mem_limit = pb->pmemext->ex_end;
    855 	} else {
    856 		mem_base  = 0x100000;	/* 1M */
    857 		mem_limit = 0x000000;
    858 	}
    859 	mem = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG);
    860 	if (!PCI_BRIDGE_PREFETCHMEM_64BITS(mem) && mem_limit > 0xFFFFFFFFULL) {
    861 		printf("Bus %d bridge does not support 64-bit PMEM.  ",
    862 		    pb->busno);
    863 		printf("Disabling prefetchable-MEM accesses\n");
    864 		mem_base  = 0x100000;	/* 1M */
    865 		mem_limit = 0x000000;
    866 	}
    867 	mem = (((mem_base >> 20) & PCI_BRIDGE_PREFETCHMEM_BASE_MASK)
    868 	    << PCI_BRIDGE_PREFETCHMEM_BASE_SHIFT);
    869 	mem |= (((mem_limit >> 20) & PCI_BRIDGE_PREFETCHMEM_LIMIT_MASK)
    870 	    << PCI_BRIDGE_PREFETCHMEM_LIMIT_SHIFT);
    871 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG, mem);
    872 	/*
    873 	 * XXX -- 64-bit systems need a lot more than just this...
    874 	 */
    875 	if (sizeof(u_long) > 4) {
    876 		mem_base  = (int64_t) mem_base  >> 32;
    877 		mem_limit = (int64_t) mem_limit >> 32;
    878 	}
    879 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHBASE32_REG,
    880 	    mem_base & 0xffffffff);
    881 	pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHLIMIT32_REG,
    882 	    mem_limit & 0xffffffff);
    883 
    884 	rv = configure_bus(pb);
    885 
    886 	if (pb->ioext)
    887 		extent_destroy(pb->ioext);
    888 	if (pb->memext)
    889 		extent_destroy(pb->memext);
    890 	if (pb->pmemext)
    891 		extent_destroy(pb->pmemext);
    892 	if (rv == 0) {
    893 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_BRIDGE_CONTROL_REG);
    894 		cmd &= PCI_BRIDGE_CONTROL_MASK;
    895 		cmd |= (PCI_BRIDGE_CONTROL_PERE | PCI_BRIDGE_CONTROL_SERR)
    896 		    << PCI_BRIDGE_CONTROL_SHIFT;
    897 		if (pb->fast_b2b) {
    898 			cmd |= PCI_BRIDGE_CONTROL_SECFASTB2B
    899 			    << PCI_BRIDGE_CONTROL_SHIFT;
    900 		}
    901 		pci_conf_write(pd->pc, pd->tag, PCI_BRIDGE_CONTROL_REG, cmd);
    902 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG);
    903 		cmd |= PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE;
    904 		pci_conf_write(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG, cmd);
    905 	}
    906 
    907 	return rv;
    908 }
    909 
    910 /*
    911  * Calculate latency values, allocate I/O and MEM segments, then set them
    912  * up.  If a PCI-PCI bridge is found, configure the bridge separately,
    913  * which will cause a recursive call back here.
    914  */
    915 static int
    916 configure_bus(pciconf_bus_t *pb)
    917 {
    918 	pciconf_dev_t	*pd;
    919 	int		def_ltim, max_ltim, band, bus_mhz;
    920 
    921 	bus_mhz = pb->freq_66 ? 66 : 33;
    922 	max_ltim = pb->max_mingnt * bus_mhz / 4;	/* cvt to cycle count */
    923 	band = 40000000;			/* 0.25us cycles/sec */
    924 	if (band < pb->bandwidth_used) {
    925 		printf("PCI bus %d: Warning: Total bandwidth exceeded!?\n",
    926 		    pb->busno);
    927 		def_ltim = -1;
    928 	} else {
    929 		def_ltim = (band - pb->bandwidth_used) / pb->ndevs;
    930 		if (def_ltim > pb->min_maxlat)
    931 			def_ltim = pb->min_maxlat;
    932 		def_ltim = def_ltim * bus_mhz / 4;
    933 	}
    934 	def_ltim = (def_ltim + 7) & ~7;
    935 	max_ltim = (max_ltim + 7) & ~7;
    936 
    937 	pb->def_ltim = MIN( def_ltim, 255 );
    938 	pb->max_ltim = MIN( MAX(max_ltim, def_ltim ), 255 );
    939 
    940 	/*
    941 	 * Now we have what we need to initialize the devices.
    942 	 * It would probably be better if we could allocate all of these
    943 	 * for all busses at once, but "not right now".  First, get a list
    944 	 * of free memory ranges from the m.d. system.
    945 	 */
    946 	if (setup_iowins(pb) || setup_memwins(pb)) {
    947 		printf("PCI bus configuration failed: ");
    948 		printf("unable to assign all I/O and memory ranges.");
    949 		return -1;
    950 	}
    951 
    952 	/*
    953 	 * Configure the latency for the devices, and enable them.
    954 	 */
    955 	for (pd=pb->device ; pd < &pb->device[pb->ndevs] ; pd++) {
    956 		pcireg_t cmd, class, misc;
    957 		int	ltim;
    958 
    959 		if (pci_conf_debug) {
    960 			print_tag(pd->pc, pd->tag);
    961 			printf("Configuring device.\n");
    962 		}
    963 		class = pci_conf_read(pd->pc, pd->tag, PCI_CLASS_REG);
    964 		misc = pci_conf_read(pd->pc, pd->tag, PCI_BHLC_REG);
    965 		cmd = pci_conf_read(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG);
    966 		cmd |= PCI_COMMAND_SERR_ENABLE | PCI_COMMAND_PARITY_ENABLE;
    967 		if (pb->fast_b2b)
    968 			cmd |= PCI_COMMAND_BACKTOBACK_ENABLE;
    969 		if (PCI_CLASS(class) != PCI_CLASS_BRIDGE ||
    970 		    PCI_SUBCLASS(class) != PCI_SUBCLASS_BRIDGE_PCI) {
    971 			if (pd->enable & PCI_CONF_ENABLE_IO)
    972 				cmd |= PCI_COMMAND_IO_ENABLE;
    973 			if (pd->enable & PCI_CONF_ENABLE_MEM)
    974 				cmd |= PCI_COMMAND_MEM_ENABLE;
    975 			if (pd->enable & PCI_CONF_ENABLE_BM)
    976 				cmd |= PCI_COMMAND_MASTER_ENABLE;
    977 			ltim = pd->min_gnt * bus_mhz / 4;
    978 			ltim = MIN (MAX (pb->def_ltim, ltim), pb->max_ltim);
    979 		} else {
    980 			cmd |= PCI_COMMAND_MASTER_ENABLE;
    981 			ltim = MIN (pb->def_ltim, pb->max_ltim);
    982 		}
    983 		if (!(pd->enable)) {
    984 			print_tag(pd->pc, pd->tag);
    985 			printf("Disabled due to lack of resources.\n");
    986 			cmd &= ~(PCI_COMMAND_MASTER_ENABLE |
    987 			    PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
    988 		}
    989 		pci_conf_write(pd->pc, pd->tag, PCI_COMMAND_STATUS_REG, cmd);
    990 
    991 		misc &= ~((PCI_LATTIMER_MASK << PCI_LATTIMER_SHIFT) |
    992 		    (PCI_CACHELINE_MASK << PCI_CACHELINE_SHIFT));
    993 		misc |= (ltim & PCI_LATTIMER_MASK) << PCI_LATTIMER_SHIFT;
    994 		misc |= ((pb->cacheline_size >> 2) & PCI_CACHELINE_MASK) <<
    995 		    PCI_CACHELINE_SHIFT;
    996 		pci_conf_write(pd->pc, pd->tag, PCI_BHLC_REG, misc);
    997 
    998 		if (pd->ppb) {
    999 			if (configure_bridge(pd) < 0)
   1000 				return -1;
   1001 			continue;
   1002 		}
   1003 	}
   1004 
   1005 	if (pci_conf_debug) {
   1006 		printf("PCI bus %d configured\n", pb->busno);
   1007 	}
   1008 
   1009 	return 0;
   1010 }
   1011 
   1012 /*
   1013  * Let's configure the PCI bus.
   1014  * This consists of basically scanning for all existing devices,
   1015  * identifying their needs, and then making another pass over them
   1016  * to set:
   1017  *	1. I/O addresses
   1018  *	2. Memory addresses (Prefetchable and not)
   1019  *	3. PCI command register
   1020  *	4. The latency part of the PCI BHLC (BIST (Built-In Self Test),
   1021  *	    Header type, Latency timer, Cache line size) register
   1022  *
   1023  * The command register is set to enable fast back-to-back transactions
   1024  * if the host bridge says it can handle it.  We also configure
   1025  * Master Enable, SERR enable, parity enable, and (if this is not a
   1026  * PCI-PCI bridge) the I/O and Memory spaces.  Apparently some devices
   1027  * will not report some I/O space.
   1028  *
   1029  * The latency is computed to be a "fair share" of the bus bandwidth.
   1030  * The bus bandwidth variable is initialized to the number of PCI cycles
   1031  * in one second.  The number of cycles taken for one transaction by each
   1032  * device (MAX_LAT + MIN_GNT) is then subtracted from the bandwidth.
   1033  * Care is taken to ensure that the latency timer won't be set such that
   1034  * it would exceed the critical time for any device.
   1035  *
   1036  * This is complicated somewhat due to the presence of bridges.  PCI-PCI
   1037  * bridges are probed and configured recursively.
   1038  */
   1039 int
   1040 pci_configure_bus(pci_chipset_tag_t pc, struct extent *ioext,
   1041     struct extent *memext, struct extent *pmemext, int firstbus,
   1042     int cacheline_size)
   1043 {
   1044 	pciconf_bus_t	*pb;
   1045 	int		rv;
   1046 
   1047 	pb = malloc (sizeof (pciconf_bus_t), M_DEVBUF, M_NOWAIT);
   1048 	pb->busno = firstbus;
   1049 	pb->busno_spacing = PCI_BUSNO_SPACING;
   1050 	pb->next_busno = pb->busno + 1;
   1051 	pb->last_busno = 255;
   1052 	pb->cacheline_size = cacheline_size;
   1053 	pb->parent_bus = NULL;
   1054 	pb->swiz = 0;
   1055 	pb->io_32bit = 1;
   1056 	pb->pmem_64bit = 0;
   1057 	pb->ioext = ioext;
   1058 	pb->memext = memext;
   1059 	if (pmemext == NULL) {
   1060 		pb->pmemext = memext;
   1061 	} else {
   1062 		pb->pmemext = pmemext;
   1063 	}
   1064 	pb->pc = pc;
   1065 	pb->io_total = pb->mem_total = pb->pmem_total = 0;
   1066 
   1067 	rv = probe_bus(pb);
   1068 	if (rv == 0) {
   1069 		rv = configure_bus(pb);
   1070 	}
   1071 
   1072 	/*
   1073 	 * All done!
   1074 	 */
   1075 	free(pb, M_DEVBUF);
   1076 	return rv;
   1077 }
   1078