xref: /netbsd-src/sys/dev/acpi/acpi_mcfg.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: acpi_mcfg.c,v 1.6 2018/04/06 17:30:25 maxv Exp $	*/
2 
3 /*-
4  * Copyright (C) 2015 NONAKA Kimihiro <nonaka@NetBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: acpi_mcfg.c,v 1.6 2018/04/06 17:30:25 maxv Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/device.h>
33 #include <sys/kmem.h>
34 #include <sys/systm.h>
35 
36 #include <dev/pci/pcireg.h>
37 #include <dev/pci/pcivar.h>
38 #include <dev/pci/pcidevs.h>
39 
40 #include <dev/acpi/acpireg.h>
41 #include <dev/acpi/acpivar.h>
42 #include <dev/acpi/acpi_mcfg.h>
43 
44 #include "locators.h"
45 
46 #define _COMPONENT      ACPI_RESOURCE_COMPONENT
47 ACPI_MODULE_NAME	("acpi_mcfg")
48 
49 #define	EXTCONF_OFFSET(d, f, r)	((((d) * 8 + (f)) * PCI_EXTCONF_SIZE) + (r))
50 
51 #define	EXTCONF_SET_VALID(mb, d, f)	((mb)->valid_devs[(d)] |= __BIT((f)))
52 #define	EXTCONF_SET_INVALID(mb, d, f)	((mb)->valid_devs[(d)] &= ~__BIT((f)))
53 #define	EXTCONF_IS_VALID(mb, d, f)	((mb)->valid_devs[(d)] & __BIT((f)))
54 
55 struct mcfg_segment {
56 	uint64_t ms_address;		/* Base address */
57 	int ms_segment;			/* Segment # */
58 	int ms_bus_start;		/* Start bus # */
59 	int ms_bus_end;			/* End bus # */
60 	bus_space_tag_t ms_bst;
61 	struct mcfg_bus {
62 		bus_space_handle_t bsh[32][8];
63 		uint8_t valid_devs[32];
64 		int valid_ndevs;
65 		pcitag_t last_probed;
66 	} *ms_bus;
67 };
68 
69 static struct mcfg_segment *mcfg_segs;
70 static int mcfg_nsegs;
71 static ACPI_TABLE_MCFG *mcfg;
72 static int mcfg_inited;
73 static struct acpi_softc *acpi_sc;
74 
75 static const struct acpimcfg_ops mcfg_default_ops = {
76 	.ao_validate = acpimcfg_default_validate,
77 
78 	.ao_read = acpimcfg_default_read,
79 	.ao_write = acpimcfg_default_write,
80 };
81 static const struct acpimcfg_ops *mcfg_ops = &mcfg_default_ops;
82 
83 /*
84  * default operations.
85  */
86 bool
87 acpimcfg_default_validate(uint64_t address, int bus_start, int *bus_end)
88 {
89 
90 	/* Always Ok */
91 	return true;
92 }
93 
94 uint32_t
95 acpimcfg_default_read(bus_space_tag_t bst, bus_space_handle_t bsh,
96     bus_addr_t addr)
97 {
98 
99 	return bus_space_read_4(bst, bsh, addr);
100 }
101 
102 void
103 acpimcfg_default_write(bus_space_tag_t bst, bus_space_handle_t bsh,
104     bus_addr_t addr, uint32_t data)
105 {
106 
107 	bus_space_write_4(bst, bsh, addr, data);
108 }
109 
110 
111 /*
112  * Check MCFG memory region at system resource
113  */
114 struct acpimcfg_memrange {
115 	const char	*hid;
116 	uint64_t	address;
117 	int		bus_start;
118 	int		bus_end;
119 	bool		found;
120 };
121 
122 static ACPI_STATUS
123 acpimcfg_parse_callback(ACPI_RESOURCE *res, void *ctx)
124 {
125 	struct acpimcfg_memrange *mr = ctx;
126 	const char *type;
127 	uint64_t size, mapaddr, mapsize;
128 	int n;
129 
130 	switch (res->Type) {
131 	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
132 		type = "FIXED_MEMORY32";
133 		mapaddr = res->Data.FixedMemory32.Address;
134 		mapsize = res->Data.FixedMemory32.AddressLength;
135 		break;
136 
137 	case ACPI_RESOURCE_TYPE_ADDRESS32:
138 		/* XXX Only fixed size supported for now */
139 		if (res->Data.Address32.Address.AddressLength == 0 ||
140 		    res->Data.Address32.ProducerConsumer != ACPI_CONSUMER)
141 			goto out;
142 
143 		if (res->Data.Address32.ResourceType != ACPI_MEMORY_RANGE)
144 			goto out;
145 
146 		if (res->Data.Address32.MinAddressFixed != ACPI_ADDRESS_FIXED ||
147 		    res->Data.Address32.MaxAddressFixed != ACPI_ADDRESS_FIXED)
148 			goto out;
149 
150 		type = "ADDRESS32";
151 		mapaddr = res->Data.Address32.Address.Minimum;
152 		mapsize = res->Data.Address32.Address.AddressLength;
153 		break;
154 
155 #ifdef _LP64
156 	case ACPI_RESOURCE_TYPE_ADDRESS64:
157 		/* XXX Only fixed size supported for now */
158 		if (res->Data.Address64.Address.AddressLength == 0 ||
159 		    res->Data.Address64.ProducerConsumer != ACPI_CONSUMER)
160 			goto out;
161 
162 		if (res->Data.Address64.ResourceType != ACPI_MEMORY_RANGE)
163 			goto out;
164 
165 		if (res->Data.Address64.MinAddressFixed != ACPI_ADDRESS_FIXED ||
166 		    res->Data.Address64.MaxAddressFixed != ACPI_ADDRESS_FIXED)
167 			goto out;
168 
169 		type = "ADDRESS64";
170 		mapaddr = res->Data.Address64.Address.Minimum;
171 		mapsize = res->Data.Address64.Address.AddressLength;
172 		break;
173 #endif
174 
175 	default:
176  out:
177 		aprint_debug_dev(acpi_sc->sc_dev, "MCFG: %s: Type=%d\n",
178 		    mr->hid, res->Type);
179 		return_ACPI_STATUS(AE_OK);
180 	}
181 
182 	aprint_debug_dev(acpi_sc->sc_dev, "MCFG: %s: Type=%d(%s), "
183 	    "Address=0x%016" PRIx64 ", Length=0x%016" PRIx64 "\n",
184 	    mr->hid, res->Type, type, mapaddr, mapsize);
185 
186 	if (mr->address < mapaddr || mr->address >= mapaddr + mapsize)
187 		return_ACPI_STATUS(AE_OK);
188 
189 	size = (mr->bus_end - mr->bus_start + 1) * ACPIMCFG_SIZE_PER_BUS;
190 
191 	/* full map */
192 	if (mr->address + size <= mapaddr + mapsize) {
193 		mr->found = true;
194 		return_ACPI_STATUS(AE_CTRL_TERMINATE);
195 	}
196 
197 	/* partial map */
198 	n = (mapsize - (mr->address - mapaddr)) / ACPIMCFG_SIZE_PER_BUS;
199 	/* bus_start == bus_end is not allowed. */
200 	if (n > 1) {
201 		mr->bus_end = mr->bus_start + n - 1;
202 		mr->found = true;
203 		return_ACPI_STATUS(AE_CTRL_TERMINATE);
204 	}
205 
206 	aprint_debug_dev(acpi_sc->sc_dev, "MCFG: bus %d-%d, "
207 	    "address 0x%016" PRIx64 ": invalid size: request 0x%016" PRIx64
208 	    ", actual 0x%016" PRIx64 "\n",
209 	    mr->bus_start, mr->bus_end, mr->address, size, mapsize);
210 
211 	return_ACPI_STATUS(AE_OK);
212 }
213 
214 static ACPI_STATUS
215 acpimcfg_check_system_resource(ACPI_HANDLE handle, UINT32 level, void *ctx,
216     void **retval)
217 {
218 	struct acpimcfg_memrange *mr = ctx;
219 	ACPI_STATUS status;
220 
221 	status = AcpiWalkResources(handle, "_CRS", acpimcfg_parse_callback, mr);
222 	if (ACPI_FAILURE(status))
223 		return_ACPI_STATUS(status);
224 
225 	if (mr->found)
226 		return_ACPI_STATUS(AE_CTRL_TERMINATE);
227 
228 	aprint_debug_dev(acpi_sc->sc_dev, "MCFG: %s: bus %d-%d, "
229 	    "address 0x%016" PRIx64 ": no valid region\n", mr->hid,
230 	    mr->bus_start, mr->bus_end, mr->address);
231 
232 	return_ACPI_STATUS(AE_OK);
233 }
234 
235 static bool
236 acpimcfg_find_system_resource(uint64_t address, int bus_start, int *bus_end)
237 {
238 	static const char *system_resource_hid[] = {
239 		"PNP0C01",	/* System Board */
240 		"PNP0C02"	/* General ID for reserving resources */
241 	};
242 	struct acpimcfg_memrange mr;
243 	ACPI_STATUS status;
244 	int i;
245 
246 	mr.address = address;
247 	mr.bus_start = bus_start;
248 	mr.bus_end = *bus_end;
249 	mr.found = false;
250 
251 	for (i = 0; i < __arraycount(system_resource_hid); i++) {
252 		mr.hid = system_resource_hid[i];
253 		status = AcpiGetDevices(__UNCONST(system_resource_hid[i]),
254 		    acpimcfg_check_system_resource, &mr, NULL);
255 		if (ACPI_FAILURE(status))
256 			continue;
257 		if (mr.found) {
258 			*bus_end = mr.bus_end;
259 			return true;
260 		}
261 	}
262 	return false;
263 }
264 
265 
266 /*
267  * ACPI MCFG
268  */
269 void
270 acpimcfg_probe(struct acpi_softc *sc)
271 {
272 	ACPI_MCFG_ALLOCATION *ama;
273 	ACPI_STATUS status;
274 	uint32_t offset;
275 	int i, nsegs;
276 
277 	if (acpi_sc != NULL)
278 		panic("acpi_sc != NULL");
279 	acpi_sc = sc;
280 
281 	status = AcpiGetTable(ACPI_SIG_MCFG, 0, (ACPI_TABLE_HEADER **)&mcfg);
282 	if (ACPI_FAILURE(status)) {
283 		mcfg = NULL;
284 		return;
285 	}
286 
287 	nsegs = 0;
288 	offset = sizeof(ACPI_TABLE_MCFG);
289 	ama = ACPI_ADD_PTR(ACPI_MCFG_ALLOCATION, mcfg, offset);
290 	for (i = 0; offset + sizeof(ACPI_MCFG_ALLOCATION) <=
291 	    mcfg->Header.Length; i++) {
292 		aprint_debug_dev(sc->sc_dev,
293 		    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64 "\n",
294 		    ama->PciSegment, ama->StartBusNumber, ama->EndBusNumber,
295 		    ama->Address);
296 		nsegs++;
297 		offset += sizeof(ACPI_MCFG_ALLOCATION);
298 		ama = ACPI_ADD_PTR(ACPI_MCFG_ALLOCATION, ama, offset);
299 	}
300 	if (nsegs == 0) {
301 		mcfg = NULL;
302 		return;
303 	}
304 
305 	mcfg_segs = kmem_zalloc(sizeof(*mcfg_segs) * nsegs, KM_SLEEP);
306 	mcfg_nsegs = nsegs;
307 }
308 
309 int
310 acpimcfg_init(bus_space_tag_t memt, const struct acpimcfg_ops *ops)
311 {
312 	ACPI_MCFG_ALLOCATION *ama;
313 	struct mcfg_segment *seg;
314 	uint32_t offset;
315 	int i, n, nsegs, bus_end;
316 
317 	if (mcfg == NULL)
318 		return ENXIO;
319 
320 	if (mcfg_inited)
321 		return 0;
322 
323 	if (ops != NULL)
324 		mcfg_ops = ops;
325 
326 	nsegs = 0;
327 	offset = sizeof(ACPI_TABLE_MCFG);
328 	ama = ACPI_ADD_PTR(ACPI_MCFG_ALLOCATION, mcfg, offset);
329 	for (i = 0; offset < mcfg->Header.Length; i++) {
330 #ifndef _LP64
331 		if (ama->Address >= 0x100000000ULL) {
332 			aprint_debug_dev(acpi_sc->sc_dev,
333 			    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64
334 			    ": ignore (64bit address)\n", ama->PciSegment,
335 			    ama->StartBusNumber, ama->EndBusNumber,
336 			    ama->Address);
337 			goto next;
338 		}
339 #endif
340 		/*
341 		 * Some (broken?) BIOSen have an MCFG table for an empty
342 		 * bus range.  Ignore those tables.
343 		 */
344 		if (ama->StartBusNumber == ama->EndBusNumber) {
345 			aprint_debug_dev(acpi_sc->sc_dev,
346 			    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64
347 			    ": ignore (bus %d == %d)\n", ama->PciSegment,
348 			    ama->StartBusNumber, ama->EndBusNumber,
349 			    ama->Address, ama->StartBusNumber,
350 			    ama->EndBusNumber);
351 			goto next;
352 		}
353 		if (ama->StartBusNumber > ama->EndBusNumber) {
354 			aprint_debug_dev(acpi_sc->sc_dev,
355 			    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64
356 			    ": ignore (bus %d > %d)\n", ama->PciSegment,
357 			    ama->StartBusNumber, ama->EndBusNumber,
358 			    ama->Address, ama->StartBusNumber,
359 			    ama->EndBusNumber);
360 			goto next;
361 		}
362 
363 		/* Validate MCFG memory range */
364 		bus_end = ama->EndBusNumber;
365 		if (mcfg_ops->ao_validate != NULL &&
366 		    !mcfg_ops->ao_validate(ama->Address, ama->StartBusNumber,
367 		      &bus_end)) {
368 			if (!acpimcfg_find_system_resource( ama->Address,
369 			    ama->StartBusNumber, &bus_end)) {
370 				aprint_debug_dev(acpi_sc->sc_dev,
371 				    "MCFG: segment %d, bus %d-%d, "
372 				    "address 0x%016" PRIx64
373 				    ": ignore (invalid address)\n",
374 				    ama->PciSegment,
375 				    ama->StartBusNumber, ama->EndBusNumber,
376 				    ama->Address);
377 				goto next;
378 			}
379 		}
380 		if (ama->EndBusNumber != bus_end) {
381 			aprint_debug_dev(acpi_sc->sc_dev,
382 			    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64
383 			    " -> bus %d-%d\n", ama->PciSegment,
384 			    ama->StartBusNumber, ama->EndBusNumber,
385 			    ama->Address, ama->StartBusNumber, bus_end);
386 		}
387 
388 		if (ama->PciSegment != 0) {
389 			aprint_debug_dev(acpi_sc->sc_dev,
390 			    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64
391 			    ": ignore (non PCI segment 0)\n", ama->PciSegment,
392 			    ama->StartBusNumber, bus_end, ama->Address);
393 			goto next;
394 		}
395 
396 		seg = &mcfg_segs[nsegs++];
397 		seg->ms_address = ama->Address;
398 		seg->ms_segment = ama->PciSegment;
399 		seg->ms_bus_start = ama->StartBusNumber;
400 		seg->ms_bus_end = bus_end;
401 		seg->ms_bst = memt;
402 		n = seg->ms_bus_end - seg->ms_bus_start + 1;
403 		seg->ms_bus = kmem_zalloc(sizeof(*seg->ms_bus) * n, KM_SLEEP);
404 
405  next:
406 		offset += sizeof(ACPI_MCFG_ALLOCATION);
407 		ama = ACPI_ADD_PTR(ACPI_MCFG_ALLOCATION, ama, offset);
408 	}
409 	if (nsegs == 0)
410 		return ENOENT;
411 
412 	for (i = 0; i < nsegs; i++) {
413 		seg = &mcfg_segs[i];
414 		aprint_verbose_dev(acpi_sc->sc_dev,
415 		    "MCFG: segment %d, bus %d-%d, address 0x%016" PRIx64 "\n",
416 		    seg->ms_segment, seg->ms_bus_start, seg->ms_bus_end,
417 		    seg->ms_address);
418 	}
419 
420 	/* Update # of segment */
421 	mcfg_nsegs = nsegs;
422 	mcfg_inited = true;
423 
424 	return 0;
425 }
426 
427 static int
428 acpimcfg_ext_conf_is_aliased(pci_chipset_tag_t pc, pcitag_t tag)
429 {
430 	pcireg_t id;
431 	int i;
432 
433 	id = pci_conf_read(pc, tag, PCI_ID_REG);
434 	for (i = PCI_CONF_SIZE; i < PCI_EXTCONF_SIZE; i += PCI_CONF_SIZE) {
435 		if (pci_conf_read(pc, tag, i) != id)
436 			return false;
437 	}
438 	return true;
439 }
440 
441 static struct mcfg_segment *
442 acpimcfg_get_segment(int bus)
443 {
444 	struct mcfg_segment *seg;
445 	int i;
446 
447 	for (i = 0; i < mcfg_nsegs; i++) {
448 		seg = &mcfg_segs[i];
449 		if (bus >= seg->ms_bus_start && bus <= seg->ms_bus_end)
450 			return seg;
451 	}
452 	return NULL;
453 }
454 
455 static int
456 acpimcfg_device_probe(const struct pci_attach_args *pa)
457 {
458 	pci_chipset_tag_t pc = pa->pa_pc;
459 	struct mcfg_segment *seg;
460 	struct mcfg_bus *mb;
461 	pcitag_t tag;
462 	pcireg_t reg;
463 	int bus = pa->pa_bus;
464 	int dev = pa->pa_device;
465 	int func = pa->pa_function;
466 	int last_dev, last_func, end_func;
467 	int alias = 0;
468 	const struct pci_quirkdata *qd;
469 	bool force_hasextcnf = false;
470 	bool force_noextcnf = false;
471 	int i, j;
472 
473 	seg = acpimcfg_get_segment(bus);
474 	if (seg == NULL)
475 		return 0;
476 
477 	mb = &seg->ms_bus[bus - seg->ms_bus_start];
478 	tag = pci_make_tag(pc, bus, dev, func);
479 
480 	/* Mark invalid between last probed device to probed device. */
481 	pci_decompose_tag(pc, mb->last_probed, NULL, &last_dev, &last_func);
482 	if (dev != 0 || func != 0) {
483 		for (i = last_dev; i <= dev; i++) {
484 			end_func = (i == dev) ? func : 8;
485 			for (j = last_func; j < end_func; j++) {
486 				if (i == last_dev && j == last_func)
487 					continue;
488 				EXTCONF_SET_INVALID(mb, i, j);
489 			}
490 			last_func = 0;
491 		}
492 	}
493 	mb->last_probed = tag;
494 
495 	reg = pci_conf_read(pc, tag, PCI_ID_REG);
496 	qd = pci_lookup_quirkdata(PCI_VENDOR(reg), PCI_PRODUCT(reg));
497 	if (qd != NULL && (qd->quirks & PCI_QUIRK_HASEXTCNF) != 0)
498 		force_hasextcnf = true;
499 	if (qd != NULL && (qd->quirks & PCI_QUIRK_NOEXTCNF) != 0)
500 		force_noextcnf = true;
501 
502 	/* Probe extended configuration space. */
503 	if ((!force_hasextcnf) && ((force_noextcnf) ||
504 		((reg = pci_conf_read(pc, tag, PCI_CONF_SIZE)) == (pcireg_t)-1)
505 		|| (reg == 0)
506 		|| (alias = acpimcfg_ext_conf_is_aliased(pc, tag)))) {
507 		aprint_debug_dev(acpi_sc->sc_dev,
508 		    "MCFG: %03d:%02d:%d: invalid config space "
509 		    "(cfg[0x%03x]=0x%08x, alias=%s)\n", bus, dev, func,
510 		    PCI_CONF_SIZE, reg, alias ? "true" : "false");
511 		EXTCONF_SET_INVALID(mb, dev, func);
512 	} else {
513 		aprint_debug_dev(acpi_sc->sc_dev,
514 		    "MCFG: %03d:%02d:%d: Ok (cfg[0x%03x]=0x%08x)\n",
515 		    bus, dev, func, PCI_CONF_SIZE, reg);
516 		mb->valid_ndevs++;
517 	}
518 
519 	return 0;
520 }
521 
522 static void
523 acpimcfg_scan_bus(struct pci_softc *sc, pci_chipset_tag_t pc, int bus)
524 {
525 	static const int wildcard[PCICF_NLOCS] = {
526 		PCICF_DEV_DEFAULT, PCICF_FUNCTION_DEFAULT
527 	};
528 
529 	sc->sc_bus = bus;	/* XXX */
530 
531 	pci_enumerate_bus(sc, wildcard, acpimcfg_device_probe, NULL);
532 }
533 
534 int
535 acpimcfg_map_bus(device_t self, pci_chipset_tag_t pc, int bus)
536 {
537 	struct pci_softc *sc = device_private(self);
538 	struct mcfg_segment *seg = NULL;
539 	struct mcfg_bus *mb;
540 	bus_space_handle_t bsh;
541 	bus_addr_t baddr;
542 	pcitag_t tag;
543 	pcireg_t reg;
544 	bool is_e7520_mch;
545 	int boff;
546 	int last_dev, last_func;
547 	int i, j;
548 	int error;
549 
550 	if (!mcfg_inited)
551 		return ENXIO;
552 
553 	seg = acpimcfg_get_segment(bus);
554 	if (seg == NULL)
555 		return ENOENT;
556 
557 	boff = bus - seg->ms_bus_start;
558 	if (seg->ms_bus[boff].valid_ndevs > 0)
559 		return 0;
560 
561 	mb = &seg->ms_bus[boff];
562 	baddr = seg->ms_address + (boff * ACPIMCFG_SIZE_PER_BUS);
563 
564 	/* Map extended configration space of all dev/func. */
565 	error = bus_space_map(seg->ms_bst, baddr, ACPIMCFG_SIZE_PER_BUS, 0,
566 	    &bsh);
567 	if (error != 0)
568 		return error;
569 	for (i = 0; i < 32; i++) {
570 		for (j = 0; j < 8; j++) {
571 			error = bus_space_subregion(seg->ms_bst, bsh,
572 			    EXTCONF_OFFSET(i, j, 0), PCI_EXTCONF_SIZE,
573 			    &mb->bsh[i][j]);
574 			if (error != 0)
575 				break;
576 		}
577 	}
578 	if (error != 0)
579 		return error;
580 
581 	aprint_debug("\n");
582 
583 	/* Probe extended configuration space of all devices. */
584 	memset(mb->valid_devs, 0xff, sizeof(mb->valid_devs));
585 	mb->valid_ndevs = 0;
586 	mb->last_probed = pci_make_tag(pc, bus, 0, 0);
587 
588 	/*
589 	 * On an Intel E7520 we have to temporarily disable
590 	 * Enhanced Config Access error detection and reporting
591 	 * by setting the appropriate error mask in HI_ERRMASK register.
592 	 *
593 	 * See "Intel E7520 Memory Controller Hub (MCH) Datasheet",
594 	 * Document 303006-002, pg. 82
595 	 */
596 	tag = pci_make_tag(pc, 0, 0, 1);
597 	reg = pci_conf_read(pc, tag, PCI_ID_REG);
598 	is_e7520_mch = (reg ==
599 	    PCI_ID_CODE(PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_E7525_MCHER));
600 	if (is_e7520_mch) {
601 		reg = pci_conf_read(pc, tag, 0x54);
602 		pci_conf_write(pc, tag, 0x54, reg | 0x20);
603 	}
604 
605 	acpimcfg_scan_bus(sc, pc, bus);
606 
607 	if (is_e7520_mch) {
608 		pci_conf_write(pc, tag, 0x54, reg);
609 	}
610 
611 	/* Unmap extended configration space of all dev/func. */
612 	bus_space_unmap(seg->ms_bst, bsh, ACPIMCFG_SIZE_PER_BUS);
613 	memset(mb->bsh, 0, sizeof(mb->bsh));
614 
615 	if (mb->valid_ndevs == 0) {
616 		aprint_debug_dev(acpi_sc->sc_dev,
617 		    "MCFG: bus %d: no valid devices.\n", bus);
618 		memset(mb->valid_devs, 0, sizeof(mb->valid_devs));
619 		goto out;
620 	}
621 
622 	/* Mark invalid on remaining all devices. */
623 	pci_decompose_tag(pc, mb->last_probed, NULL, &last_dev, &last_func);
624 	for (i = last_dev; i < 32; i++) {
625 		for (j = last_func; j < 8; j++) {
626 			if (i == last_dev && j == last_func) {
627 				/* Don't mark invalid to last probed device. */
628 				continue;
629 			}
630 			EXTCONF_SET_INVALID(mb, i, j);
631 		}
632 		last_func = 0;
633 	}
634 
635 	/* Map extended configuration space per dev/func. */
636 	for (i = 0; i < 32; i++) {
637 		for (j = 0; j < 8; j++) {
638 			if (!EXTCONF_IS_VALID(mb, i, j))
639 				continue;
640 			error = bus_space_map(seg->ms_bst,
641 			    baddr + EXTCONF_OFFSET(i, j, 0), PCI_EXTCONF_SIZE,
642 			    0, &mb->bsh[i][j]);
643 			if (error != 0) {
644 				/* Unmap all handles when map failed. */
645 				do {
646 					while (--j >= 0) {
647 						if (!EXTCONF_IS_VALID(mb, i, j))
648 							continue;
649 						bus_space_unmap(seg->ms_bst,
650 						    mb->bsh[i][j],
651 						    PCI_EXTCONF_SIZE);
652 					}
653 					j = 8;
654 				} while (--i >= 0);
655 				memset(mb->valid_devs, 0,
656 				    sizeof(mb->valid_devs));
657 				goto out;
658 			}
659 		}
660 	}
661 
662 	aprint_debug_dev(acpi_sc->sc_dev, "MCFG: bus %d: valid devices\n", bus);
663 	for (i = 0; i < 32; i++) {
664 		for (j = 0; j < 8; j++) {
665 			if (EXTCONF_IS_VALID(mb, i, j)) {
666 				aprint_debug_dev(acpi_sc->sc_dev,
667 				    "MCFG: %03d:%02d:%d\n", bus, i, j);
668 			}
669 		}
670 	}
671 
672 	error = 0;
673 out:
674 	aprint_debug_dev(acpi_sc->sc_dev, "%s done", __func__);
675 
676 	return error;
677 }
678 
679 int
680 acpimcfg_conf_read(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t *data)
681 {
682 	struct mcfg_segment *seg = NULL;
683 	struct mcfg_bus *mb;
684 	int bus, dev, func;
685 
686 	KASSERT(reg < PCI_EXTCONF_SIZE);
687 	KASSERT((reg & 3) == 0);
688 
689 	if (!mcfg_inited) {
690 		*data = -1;
691 		return ENXIO;
692 	}
693 
694 	pci_decompose_tag(pc, tag, &bus, &dev, &func);
695 
696 	seg = acpimcfg_get_segment(bus);
697 	if (seg == NULL) {
698 		*data = -1;
699 		return ERANGE;
700 	}
701 
702 	mb = &seg->ms_bus[bus - seg->ms_bus_start];
703 	if (!EXTCONF_IS_VALID(mb, dev, func)) {
704 		*data = -1;
705 		return EINVAL;
706 	}
707 
708 	*data = mcfg_ops->ao_read(seg->ms_bst, mb->bsh[dev][func], reg);
709 	return 0;
710 }
711 
712 int
713 acpimcfg_conf_write(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t data)
714 {
715 	struct mcfg_segment *seg = NULL;
716 	struct mcfg_bus *mb;
717 	int bus, dev, func;
718 
719 	KASSERT(reg < PCI_EXTCONF_SIZE);
720 	KASSERT((reg & 3) == 0);
721 
722 	if (!mcfg_inited)
723 		return ENXIO;
724 
725 	pci_decompose_tag(pc, tag, &bus, &dev, &func);
726 
727 	seg = acpimcfg_get_segment(bus);
728 	if (seg == NULL)
729 		return ERANGE;
730 
731 	mb = &seg->ms_bus[bus - seg->ms_bus_start];
732 	if (!EXTCONF_IS_VALID(mb, dev, func))
733 		return EINVAL;
734 
735 	mcfg_ops->ao_write(seg->ms_bst, mb->bsh[dev][func], reg, data);
736 	return 0;
737 }
738