xref: /linux/arch/x86/pci/mmconfig-shared.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Low-level direct PCI config space access via ECAM - common code between
4  * i386 and x86-64.
5  *
6  * This code does:
7  * - known chipset handling
8  * - ACPI decoding and validation
9  *
10  * Per-architecture code takes care of the mappings and accesses
11  * themselves.
12  */
13 
14 #define pr_fmt(fmt) "PCI: " fmt
15 
16 #include <linux/acpi.h>
17 #include <linux/efi.h>
18 #include <linux/pci.h>
19 #include <linux/init.h>
20 #include <linux/bitmap.h>
21 #include <linux/dmi.h>
22 #include <linux/slab.h>
23 #include <linux/mutex.h>
24 #include <linux/rculist.h>
25 #include <asm/e820/api.h>
26 #include <asm/pci_x86.h>
27 #include <asm/acpi.h>
28 
29 /* Indicate if the ECAM resources have been placed into the resource table */
30 static bool pci_mmcfg_running_state;
31 static bool pci_mmcfg_arch_init_failed;
32 static DEFINE_MUTEX(pci_mmcfg_lock);
33 #define pci_mmcfg_lock_held() lock_is_held(&(pci_mmcfg_lock).dep_map)
34 
35 LIST_HEAD(pci_mmcfg_list);
36 
37 static void __init pci_mmconfig_remove(struct pci_mmcfg_region *cfg)
38 {
39 	if (cfg->res.parent)
40 		release_resource(&cfg->res);
41 	list_del(&cfg->list);
42 	kfree(cfg);
43 }
44 
45 static void __init free_all_mmcfg(void)
46 {
47 	struct pci_mmcfg_region *cfg, *tmp;
48 
49 	pci_mmcfg_arch_free();
50 	list_for_each_entry_safe(cfg, tmp, &pci_mmcfg_list, list)
51 		pci_mmconfig_remove(cfg);
52 }
53 
54 static void list_add_sorted(struct pci_mmcfg_region *new)
55 {
56 	struct pci_mmcfg_region *cfg;
57 
58 	/* keep list sorted by segment and starting bus number */
59 	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held()) {
60 		if (cfg->segment > new->segment ||
61 		    (cfg->segment == new->segment &&
62 		     cfg->start_bus >= new->start_bus)) {
63 			list_add_tail_rcu(&new->list, &cfg->list);
64 			return;
65 		}
66 	}
67 	list_add_tail_rcu(&new->list, &pci_mmcfg_list);
68 }
69 
70 static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start,
71 						   int end, u64 addr)
72 {
73 	struct pci_mmcfg_region *new;
74 	struct resource *res;
75 
76 	if (addr == 0)
77 		return NULL;
78 
79 	new = kzalloc(sizeof(*new), GFP_KERNEL);
80 	if (!new)
81 		return NULL;
82 
83 	new->address = addr;
84 	new->segment = segment;
85 	new->start_bus = start;
86 	new->end_bus = end;
87 
88 	res = &new->res;
89 	res->start = addr + PCI_MMCFG_BUS_OFFSET(start);
90 	res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1;
91 	res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
92 	snprintf(new->name, PCI_MMCFG_RESOURCE_NAME_LEN,
93 		 "PCI ECAM %04x [bus %02x-%02x]", segment, start, end);
94 	res->name = new->name;
95 
96 	return new;
97 }
98 
99 struct pci_mmcfg_region *__init pci_mmconfig_add(int segment, int start,
100 						 int end, u64 addr)
101 {
102 	struct pci_mmcfg_region *new;
103 
104 	new = pci_mmconfig_alloc(segment, start, end, addr);
105 	if (!new)
106 		return NULL;
107 
108 	mutex_lock(&pci_mmcfg_lock);
109 	list_add_sorted(new);
110 	mutex_unlock(&pci_mmcfg_lock);
111 
112 	pr_info("ECAM %pR (base %#lx) for domain %04x [bus %02x-%02x]\n",
113 		&new->res, (unsigned long)addr, segment, start, end);
114 
115 	return new;
116 }
117 
118 struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus)
119 {
120 	struct pci_mmcfg_region *cfg;
121 
122 	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held())
123 		if (cfg->segment == segment &&
124 		    cfg->start_bus <= bus && bus <= cfg->end_bus)
125 			return cfg;
126 
127 	return NULL;
128 }
129 
130 static const char *__init pci_mmcfg_e7520(void)
131 {
132 	u32 win;
133 	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0xce, 2, &win);
134 
135 	win = win & 0xf000;
136 	if (win == 0x0000 || win == 0xf000)
137 		return NULL;
138 
139 	if (pci_mmconfig_add(0, 0, 255, win << 16) == NULL)
140 		return NULL;
141 
142 	return "Intel Corporation E7520 Memory Controller Hub";
143 }
144 
145 static const char *__init pci_mmcfg_intel_945(void)
146 {
147 	u32 pciexbar, mask = 0, len = 0;
148 
149 	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0x48, 4, &pciexbar);
150 
151 	/* Enable bit */
152 	if (!(pciexbar & 1))
153 		return NULL;
154 
155 	/* Size bits */
156 	switch ((pciexbar >> 1) & 3) {
157 	case 0:
158 		mask = 0xf0000000U;
159 		len  = 0x10000000U;
160 		break;
161 	case 1:
162 		mask = 0xf8000000U;
163 		len  = 0x08000000U;
164 		break;
165 	case 2:
166 		mask = 0xfc000000U;
167 		len  = 0x04000000U;
168 		break;
169 	default:
170 		return NULL;
171 	}
172 
173 	/* Errata #2, things break when not aligned on a 256Mb boundary */
174 	/* Can only happen in 64M/128M mode */
175 
176 	if ((pciexbar & mask) & 0x0fffffffU)
177 		return NULL;
178 
179 	/* Don't hit the APIC registers and their friends */
180 	if ((pciexbar & mask) >= 0xf0000000U)
181 		return NULL;
182 
183 	if (pci_mmconfig_add(0, 0, (len >> 20) - 1, pciexbar & mask) == NULL)
184 		return NULL;
185 
186 	return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
187 }
188 
189 static const char *__init pci_mmcfg_amd_fam10h(void)
190 {
191 	u32 low, high, address;
192 	u64 base, msr;
193 	int i;
194 	unsigned segnbits = 0, busnbits, end_bus;
195 
196 	if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
197 		return NULL;
198 
199 	address = MSR_FAM10H_MMIO_CONF_BASE;
200 	if (rdmsr_safe(address, &low, &high))
201 		return NULL;
202 
203 	msr = high;
204 	msr <<= 32;
205 	msr |= low;
206 
207 	/* ECAM is not enabled */
208 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
209 		return NULL;
210 
211 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
212 
213 	busnbits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
214 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
215 
216 	/*
217 	 * only handle bus 0 ?
218 	 * need to skip it
219 	 */
220 	if (!busnbits)
221 		return NULL;
222 
223 	if (busnbits > 8) {
224 		segnbits = busnbits - 8;
225 		busnbits = 8;
226 	}
227 
228 	end_bus = (1 << busnbits) - 1;
229 	for (i = 0; i < (1 << segnbits); i++)
230 		if (pci_mmconfig_add(i, 0, end_bus,
231 				     base + (1<<28) * i) == NULL) {
232 			free_all_mmcfg();
233 			return NULL;
234 		}
235 
236 	return "AMD Family 10h NB";
237 }
238 
239 static bool __initdata mcp55_checked;
240 static const char *__init pci_mmcfg_nvidia_mcp55(void)
241 {
242 	int bus;
243 	int mcp55_mmconf_found = 0;
244 
245 	static const u32 extcfg_regnum __initconst	= 0x90;
246 	static const u32 extcfg_regsize __initconst	= 4;
247 	static const u32 extcfg_enable_mask __initconst	= 1 << 31;
248 	static const u32 extcfg_start_mask __initconst	= 0xff << 16;
249 	static const int extcfg_start_shift __initconst	= 16;
250 	static const u32 extcfg_size_mask __initconst	= 0x3 << 28;
251 	static const int extcfg_size_shift __initconst	= 28;
252 	static const int extcfg_sizebus[] __initconst	= {
253 		0x100, 0x80, 0x40, 0x20
254 	};
255 	static const u32 extcfg_base_mask[] __initconst	= {
256 		0x7ff8, 0x7ffc, 0x7ffe, 0x7fff
257 	};
258 	static const int extcfg_base_lshift __initconst	= 25;
259 
260 	/*
261 	 * do check if amd fam10h already took over
262 	 */
263 	if (!acpi_disabled || !list_empty(&pci_mmcfg_list) || mcp55_checked)
264 		return NULL;
265 
266 	mcp55_checked = true;
267 	for (bus = 0; bus < 256; bus++) {
268 		u64 base;
269 		u32 l, extcfg;
270 		u16 vendor, device;
271 		int start, size_index, end;
272 
273 		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), 0, 4, &l);
274 		vendor = l & 0xffff;
275 		device = (l >> 16) & 0xffff;
276 
277 		if (PCI_VENDOR_ID_NVIDIA != vendor || 0x0369 != device)
278 			continue;
279 
280 		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), extcfg_regnum,
281 				  extcfg_regsize, &extcfg);
282 
283 		if (!(extcfg & extcfg_enable_mask))
284 			continue;
285 
286 		size_index = (extcfg & extcfg_size_mask) >> extcfg_size_shift;
287 		base = extcfg & extcfg_base_mask[size_index];
288 		/* base could > 4G */
289 		base <<= extcfg_base_lshift;
290 		start = (extcfg & extcfg_start_mask) >> extcfg_start_shift;
291 		end = start + extcfg_sizebus[size_index] - 1;
292 		if (pci_mmconfig_add(0, start, end, base) == NULL)
293 			continue;
294 		mcp55_mmconf_found++;
295 	}
296 
297 	if (!mcp55_mmconf_found)
298 		return NULL;
299 
300 	return "nVidia MCP55";
301 }
302 
303 struct pci_mmcfg_hostbridge_probe {
304 	u32 bus;
305 	u32 devfn;
306 	u32 vendor;
307 	u32 device;
308 	const char *(*probe)(void);
309 };
310 
311 static const struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initconst = {
312 	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
313 	  PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
314 	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
315 	  PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
316 	{ 0, PCI_DEVFN(0x18, 0), PCI_VENDOR_ID_AMD,
317 	  0x1200, pci_mmcfg_amd_fam10h },
318 	{ 0xff, PCI_DEVFN(0, 0), PCI_VENDOR_ID_AMD,
319 	  0x1200, pci_mmcfg_amd_fam10h },
320 	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_NVIDIA,
321 	  0x0369, pci_mmcfg_nvidia_mcp55 },
322 };
323 
324 static void __init pci_mmcfg_check_end_bus_number(void)
325 {
326 	struct pci_mmcfg_region *cfg, *cfgx;
327 
328 	/* Fixup overlaps */
329 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
330 		if (cfg->end_bus < cfg->start_bus)
331 			cfg->end_bus = 255;
332 
333 		/* Don't access the list head ! */
334 		if (cfg->list.next == &pci_mmcfg_list)
335 			break;
336 
337 		cfgx = list_entry(cfg->list.next, typeof(*cfg), list);
338 		if (cfg->end_bus >= cfgx->start_bus)
339 			cfg->end_bus = cfgx->start_bus - 1;
340 	}
341 }
342 
343 static int __init pci_mmcfg_check_hostbridge(void)
344 {
345 	u32 l;
346 	u32 bus, devfn;
347 	u16 vendor, device;
348 	int i;
349 	const char *name;
350 
351 	if (!raw_pci_ops)
352 		return 0;
353 
354 	free_all_mmcfg();
355 
356 	for (i = 0; i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
357 		bus =  pci_mmcfg_probes[i].bus;
358 		devfn = pci_mmcfg_probes[i].devfn;
359 		raw_pci_ops->read(0, bus, devfn, 0, 4, &l);
360 		vendor = l & 0xffff;
361 		device = (l >> 16) & 0xffff;
362 
363 		name = NULL;
364 		if (pci_mmcfg_probes[i].vendor == vendor &&
365 		    pci_mmcfg_probes[i].device == device)
366 			name = pci_mmcfg_probes[i].probe();
367 
368 		if (name)
369 			pr_info("%s with ECAM support\n", name);
370 	}
371 
372 	/* some end_bus_number is crazy, fix it */
373 	pci_mmcfg_check_end_bus_number();
374 
375 	return !list_empty(&pci_mmcfg_list);
376 }
377 
378 static acpi_status check_mcfg_resource(struct acpi_resource *res, void *data)
379 {
380 	struct resource *mcfg_res = data;
381 	struct acpi_resource_address64 address;
382 	acpi_status status;
383 
384 	if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
385 		struct acpi_resource_fixed_memory32 *fixmem32 =
386 			&res->data.fixed_memory32;
387 		if (!fixmem32)
388 			return AE_OK;
389 		if ((mcfg_res->start >= fixmem32->address) &&
390 		    (mcfg_res->end < (fixmem32->address +
391 				      fixmem32->address_length))) {
392 			mcfg_res->flags = 1;
393 			return AE_CTRL_TERMINATE;
394 		}
395 	}
396 	if ((res->type != ACPI_RESOURCE_TYPE_ADDRESS32) &&
397 	    (res->type != ACPI_RESOURCE_TYPE_ADDRESS64))
398 		return AE_OK;
399 
400 	status = acpi_resource_to_address64(res, &address);
401 	if (ACPI_FAILURE(status) ||
402 	   (address.address.address_length <= 0) ||
403 	   (address.resource_type != ACPI_MEMORY_RANGE))
404 		return AE_OK;
405 
406 	if ((mcfg_res->start >= address.address.minimum) &&
407 	    (mcfg_res->end < (address.address.minimum + address.address.address_length))) {
408 		mcfg_res->flags = 1;
409 		return AE_CTRL_TERMINATE;
410 	}
411 	return AE_OK;
412 }
413 
414 static acpi_status find_mboard_resource(acpi_handle handle, u32 lvl,
415 					void *context, void **rv)
416 {
417 	struct resource *mcfg_res = context;
418 
419 	acpi_walk_resources(handle, METHOD_NAME__CRS,
420 			    check_mcfg_resource, context);
421 
422 	if (mcfg_res->flags)
423 		return AE_CTRL_TERMINATE;
424 
425 	return AE_OK;
426 }
427 
428 static bool is_acpi_reserved(u64 start, u64 end, enum e820_type not_used)
429 {
430 	struct resource mcfg_res;
431 
432 	mcfg_res.start = start;
433 	mcfg_res.end = end - 1;
434 	mcfg_res.flags = 0;
435 
436 	acpi_get_devices("PNP0C01", find_mboard_resource, &mcfg_res, NULL);
437 
438 	if (!mcfg_res.flags)
439 		acpi_get_devices("PNP0C02", find_mboard_resource, &mcfg_res,
440 				 NULL);
441 
442 	return mcfg_res.flags;
443 }
444 
445 static bool is_efi_mmio(struct resource *res)
446 {
447 #ifdef CONFIG_EFI
448 	u64 start = res->start;
449 	u64 end = res->start + resource_size(res);
450 	efi_memory_desc_t *md;
451 	u64 size, mmio_start, mmio_end;
452 
453 	for_each_efi_memory_desc(md) {
454 		if (md->type == EFI_MEMORY_MAPPED_IO) {
455 			size = md->num_pages << EFI_PAGE_SHIFT;
456 			mmio_start = md->phys_addr;
457 			mmio_end = mmio_start + size;
458 
459 			if (mmio_start <= start && end <= mmio_end)
460 				return true;
461 		}
462 	}
463 #endif
464 
465 	return false;
466 }
467 
468 typedef bool (*check_reserved_t)(u64 start, u64 end, enum e820_type type);
469 
470 static bool __ref is_mmconf_reserved(check_reserved_t is_reserved,
471 				     struct pci_mmcfg_region *cfg,
472 				     struct device *dev, const char *method)
473 {
474 	u64 addr = cfg->res.start;
475 	u64 size = resource_size(&cfg->res);
476 	u64 old_size = size;
477 	int num_buses;
478 
479 	while (!is_reserved(addr, addr + size, E820_TYPE_RESERVED)) {
480 		size >>= 1;
481 		if (size < (16UL<<20))
482 			break;
483 	}
484 
485 	if (size < (16UL<<20) && size != old_size)
486 		return false;
487 
488 	if (dev)
489 		dev_info(dev, "ECAM %pR reserved as %s\n",
490 			 &cfg->res, method);
491 	else
492 		pr_info("ECAM %pR reserved as %s\n", &cfg->res, method);
493 
494 	if (old_size != size) {
495 		/* update end_bus */
496 		cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
497 		num_buses = cfg->end_bus - cfg->start_bus + 1;
498 		cfg->res.end = cfg->res.start +
499 		    PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
500 		snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
501 			 "PCI ECAM %04x [bus %02x-%02x]",
502 			 cfg->segment, cfg->start_bus, cfg->end_bus);
503 
504 		if (dev)
505 			dev_info(dev, "ECAM %pR (base %#lx) (size reduced!)\n",
506 				 &cfg->res, (unsigned long) cfg->address);
507 		else
508 			pr_info("ECAM %pR (base %#lx) for %04x [bus%02x-%02x] (size reduced!)\n",
509 				&cfg->res, (unsigned long) cfg->address,
510 				cfg->segment, cfg->start_bus, cfg->end_bus);
511 	}
512 
513 	return true;
514 }
515 
516 static bool __ref pci_mmcfg_reserved(struct device *dev,
517 				     struct pci_mmcfg_region *cfg, int early)
518 {
519 	struct resource *conflict;
520 
521 	if (early) {
522 
523 		/*
524 		 * Don't try to do this check unless configuration type 1
525 		 * is available.  How about type 2?
526 		 */
527 
528 		/*
529 		 * 946f2ee5c731 ("Check that MCFG points to an e820
530 		 * reserved area") added this E820 check in 2006 to work
531 		 * around BIOS defects.
532 		 *
533 		 * Per PCI Firmware r3.3, sec 4.1.2, ECAM space must be
534 		 * reserved by a PNP0C02 resource, but it need not be
535 		 * mentioned in E820.  Before the ACPI interpreter is
536 		 * available, we can't check for PNP0C02 resources, so
537 		 * there's no reliable way to verify the region in this
538 		 * early check.  Keep it only for the old machines that
539 		 * motivated 946f2ee5c731.
540 		 */
541 		if (dmi_get_bios_year() < 2016 && raw_pci_ops)
542 			return is_mmconf_reserved(e820__mapped_all, cfg, dev,
543 						  "E820 entry");
544 
545 		return true;
546 	}
547 
548 	if (!acpi_disabled) {
549 		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev,
550 				       "ACPI motherboard resource"))
551 			return true;
552 
553 		if (dev)
554 			dev_info(dev, FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
555 				 &cfg->res);
556 		else
557 			pr_info(FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
558 			        &cfg->res);
559 
560 		if (is_efi_mmio(&cfg->res)) {
561 			pr_info("ECAM %pR is EfiMemoryMappedIO; assuming valid\n",
562 				&cfg->res);
563 			conflict = insert_resource_conflict(&iomem_resource,
564 							    &cfg->res);
565 			if (conflict)
566 				pr_warn("ECAM %pR conflicts with %s %pR\n",
567 					&cfg->res, conflict->name, conflict);
568 			else
569 				pr_info("ECAM %pR reserved to work around lack of ACPI motherboard _CRS\n",
570 					&cfg->res);
571 			return true;
572 		}
573 	}
574 
575 	/*
576 	 * e820__mapped_all() is marked as __init.
577 	 * All entries from ACPI MCFG table have been checked at boot time.
578 	 * For MCFG information constructed from hotpluggable host bridge's
579 	 * _CBA method, just assume it's reserved.
580 	 */
581 	return pci_mmcfg_running_state;
582 }
583 
584 static void __init pci_mmcfg_reject_broken(int early)
585 {
586 	struct pci_mmcfg_region *cfg;
587 
588 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
589 		if (!pci_mmcfg_reserved(NULL, cfg, early)) {
590 			pr_info("not using ECAM (%pR not reserved)\n",
591 				&cfg->res);
592 			free_all_mmcfg();
593 			return;
594 		}
595 	}
596 }
597 
598 static bool __init acpi_mcfg_valid_entry(struct acpi_table_mcfg *mcfg,
599 					 struct acpi_mcfg_allocation *cfg)
600 {
601 	if (cfg->address < 0xFFFFFFFF)
602 		return true;
603 
604 	if (!strncmp(mcfg->header.oem_id, "SGI", 3))
605 		return true;
606 
607 	if ((mcfg->header.revision >= 1) && (dmi_get_bios_year() >= 2010))
608 		return true;
609 
610 	pr_err("ECAM at %#llx for %04x [bus %02x-%02x] is above 4GB, ignored\n",
611 	       cfg->address, cfg->pci_segment, cfg->start_bus_number,
612 	       cfg->end_bus_number);
613 	return false;
614 }
615 
616 static int __init pci_parse_mcfg(struct acpi_table_header *header)
617 {
618 	struct acpi_table_mcfg *mcfg;
619 	struct acpi_mcfg_allocation *cfg_table, *cfg;
620 	unsigned long i;
621 	int entries;
622 
623 	if (!header)
624 		return -EINVAL;
625 
626 	mcfg = (struct acpi_table_mcfg *)header;
627 
628 	/* how many config structures do we have */
629 	free_all_mmcfg();
630 	entries = 0;
631 	i = header->length - sizeof(struct acpi_table_mcfg);
632 	while (i >= sizeof(struct acpi_mcfg_allocation)) {
633 		entries++;
634 		i -= sizeof(struct acpi_mcfg_allocation);
635 	}
636 	if (entries == 0) {
637 		pr_err("MCFG has no entries\n");
638 		return -ENODEV;
639 	}
640 
641 	cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
642 	for (i = 0; i < entries; i++) {
643 		cfg = &cfg_table[i];
644 		if (!acpi_mcfg_valid_entry(mcfg, cfg)) {
645 			free_all_mmcfg();
646 			return -ENODEV;
647 		}
648 
649 		if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
650 				   cfg->end_bus_number, cfg->address) == NULL) {
651 			pr_warn("no memory for MCFG entries\n");
652 			free_all_mmcfg();
653 			return -ENOMEM;
654 		}
655 	}
656 
657 	return 0;
658 }
659 
660 #ifdef CONFIG_ACPI_APEI
661 extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
662 				     void *data), void *data);
663 
664 static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
665 				     void *data), void *data)
666 {
667 	struct pci_mmcfg_region *cfg;
668 	int rc;
669 
670 	if (list_empty(&pci_mmcfg_list))
671 		return 0;
672 
673 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
674 		rc = func(cfg->res.start, resource_size(&cfg->res), data);
675 		if (rc)
676 			return rc;
677 	}
678 
679 	return 0;
680 }
681 #define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
682 #else
683 #define set_apei_filter()
684 #endif
685 
686 static void __init __pci_mmcfg_init(int early)
687 {
688 	pr_debug("%s(%s)\n", __func__, early ? "early" : "late");
689 
690 	pci_mmcfg_reject_broken(early);
691 	if (list_empty(&pci_mmcfg_list))
692 		return;
693 
694 	if (pcibios_last_bus < 0) {
695 		const struct pci_mmcfg_region *cfg;
696 
697 		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
698 			if (cfg->segment)
699 				break;
700 			pcibios_last_bus = cfg->end_bus;
701 		}
702 	}
703 
704 	if (pci_mmcfg_arch_init())
705 		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
706 	else {
707 		free_all_mmcfg();
708 		pci_mmcfg_arch_init_failed = true;
709 	}
710 }
711 
712 static int __initdata known_bridge;
713 
714 void __init pci_mmcfg_early_init(void)
715 {
716 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
717 
718 	if (pci_probe & PCI_PROBE_MMCONF) {
719 		if (pci_mmcfg_check_hostbridge())
720 			known_bridge = 1;
721 		else
722 			acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
723 		__pci_mmcfg_init(1);
724 
725 		set_apei_filter();
726 	}
727 }
728 
729 void __init pci_mmcfg_late_init(void)
730 {
731 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
732 
733 	/* ECAM disabled */
734 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
735 		return;
736 
737 	if (known_bridge)
738 		return;
739 
740 	/* ECAM hasn't been enabled yet, try again */
741 	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
742 		acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
743 		__pci_mmcfg_init(0);
744 	}
745 }
746 
747 static int __init pci_mmcfg_late_insert_resources(void)
748 {
749 	struct pci_mmcfg_region *cfg;
750 
751 	pci_mmcfg_running_state = true;
752 
753 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
754 
755 	/* If we are not using ECAM, don't insert the resources. */
756 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
757 		return 1;
758 
759 	/*
760 	 * Attempt to insert the mmcfg resources but not with the busy flag
761 	 * marked so it won't cause request errors when __request_region is
762 	 * called.
763 	 */
764 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
765 		if (!cfg->res.parent) {
766 			pr_debug("%s() insert %pR\n", __func__, &cfg->res);
767 			insert_resource(&iomem_resource, &cfg->res);
768 		}
769 	}
770 
771 	return 0;
772 }
773 
774 /*
775  * Perform ECAM resource insertion after PCI initialization to allow for
776  * misprogrammed MCFG tables that state larger sizes but actually conflict
777  * with other system resources.
778  */
779 late_initcall(pci_mmcfg_late_insert_resources);
780 
781 /* Add ECAM information for host bridges */
782 int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
783 			phys_addr_t addr)
784 {
785 	int rc;
786 	struct resource *tmp = NULL;
787 	struct pci_mmcfg_region *cfg;
788 
789 	dev_dbg(dev, "%s(%04x [bus %02x-%02x])\n", __func__, seg, start, end);
790 
791 	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
792 		return -ENODEV;
793 
794 	if (start > end)
795 		return -EINVAL;
796 
797 	mutex_lock(&pci_mmcfg_lock);
798 	cfg = pci_mmconfig_lookup(seg, start);
799 	if (cfg) {
800 		if (cfg->end_bus < end)
801 			dev_info(dev, FW_INFO "ECAM %pR for domain %04x [bus %02x-%02x] only partially covers this bridge\n",
802 				 &cfg->res, cfg->segment, cfg->start_bus,
803 				 cfg->end_bus);
804 		mutex_unlock(&pci_mmcfg_lock);
805 		return -EEXIST;
806 	}
807 
808 	/*
809 	 * Don't move earlier; we must return -EEXIST, not -EINVAL, if
810 	 * pci_mmconfig_lookup() finds something
811 	 */
812 	if (!addr) {
813 		mutex_unlock(&pci_mmcfg_lock);
814 		return -EINVAL;
815 	}
816 
817 	rc = -EBUSY;
818 	cfg = pci_mmconfig_alloc(seg, start, end, addr);
819 	if (cfg == NULL) {
820 		dev_warn(dev, "fail to add ECAM (out of memory)\n");
821 		rc = -ENOMEM;
822 	} else if (!pci_mmcfg_reserved(dev, cfg, 0)) {
823 		dev_warn(dev, FW_BUG "ECAM %pR isn't reserved\n",
824 			 &cfg->res);
825 	} else {
826 		/* Insert resource if it's not in boot stage */
827 		if (pci_mmcfg_running_state)
828 			tmp = insert_resource_conflict(&iomem_resource,
829 						       &cfg->res);
830 
831 		if (tmp) {
832 			dev_warn(dev, "ECAM %pR conflicts with %s %pR\n",
833 				 &cfg->res, tmp->name, tmp);
834 		} else if (pci_mmcfg_arch_map(cfg)) {
835 			dev_warn(dev, "fail to map ECAM %pR\n", &cfg->res);
836 		} else {
837 			list_add_sorted(cfg);
838 			dev_info(dev, "ECAM %pR (base %#lx)\n",
839 				 &cfg->res, (unsigned long)addr);
840 			cfg = NULL;
841 			rc = 0;
842 		}
843 	}
844 
845 	if (cfg) {
846 		if (cfg->res.parent)
847 			release_resource(&cfg->res);
848 		kfree(cfg);
849 	}
850 
851 	mutex_unlock(&pci_mmcfg_lock);
852 
853 	return rc;
854 }
855 
856 /* Delete ECAM information for host bridges */
857 int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
858 {
859 	struct pci_mmcfg_region *cfg;
860 
861 	mutex_lock(&pci_mmcfg_lock);
862 	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
863 		if (cfg->segment == seg && cfg->start_bus == start &&
864 		    cfg->end_bus == end) {
865 			list_del_rcu(&cfg->list);
866 			synchronize_rcu();
867 			pci_mmcfg_arch_unmap(cfg);
868 			if (cfg->res.parent)
869 				release_resource(&cfg->res);
870 			mutex_unlock(&pci_mmcfg_lock);
871 			kfree(cfg);
872 			return 0;
873 		}
874 	mutex_unlock(&pci_mmcfg_lock);
875 
876 	return -ENOENT;
877 }
878