xref: /linux/arch/x86/pci/mmconfig-shared.c (revision 306ec721d043bbe5e818d59fbb37c28d999b5d8b)
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 && !acpi_disabled) {
522 		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev,
523 				       "ACPI motherboard resource"))
524 			return true;
525 
526 		if (dev)
527 			dev_info(dev, FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
528 				 &cfg->res);
529 		else
530 			pr_info(FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
531 			        &cfg->res);
532 
533 		if (is_efi_mmio(&cfg->res)) {
534 			pr_info("ECAM %pR is EfiMemoryMappedIO; assuming valid\n",
535 				&cfg->res);
536 			conflict = insert_resource_conflict(&iomem_resource,
537 							    &cfg->res);
538 			if (conflict)
539 				pr_warn("ECAM %pR conflicts with %s %pR\n",
540 					&cfg->res, conflict->name, conflict);
541 			else
542 				pr_info("ECAM %pR reserved to work around lack of ACPI motherboard _CRS\n",
543 					&cfg->res);
544 			return true;
545 		}
546 	}
547 
548 	/*
549 	 * e820__mapped_all() is marked as __init.
550 	 * All entries from ACPI MCFG table have been checked at boot time.
551 	 * For MCFG information constructed from hotpluggable host bridge's
552 	 * _CBA method, just assume it's reserved.
553 	 */
554 	if (pci_mmcfg_running_state)
555 		return true;
556 
557 	/* Don't try to do this check unless configuration
558 	   type 1 is available. how about type 2 ?*/
559 	if (raw_pci_ops)
560 		return is_mmconf_reserved(e820__mapped_all, cfg, dev,
561 					  "E820 entry");
562 
563 	return false;
564 }
565 
566 static void __init pci_mmcfg_reject_broken(int early)
567 {
568 	struct pci_mmcfg_region *cfg;
569 
570 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
571 		if (!pci_mmcfg_reserved(NULL, cfg, early)) {
572 			pr_info("not using ECAM (%pR not reserved)\n",
573 				&cfg->res);
574 			free_all_mmcfg();
575 			return;
576 		}
577 	}
578 }
579 
580 static bool __init acpi_mcfg_valid_entry(struct acpi_table_mcfg *mcfg,
581 					 struct acpi_mcfg_allocation *cfg)
582 {
583 	if (cfg->address < 0xFFFFFFFF)
584 		return true;
585 
586 	if (!strncmp(mcfg->header.oem_id, "SGI", 3))
587 		return true;
588 
589 	if ((mcfg->header.revision >= 1) && (dmi_get_bios_year() >= 2010))
590 		return true;
591 
592 	pr_err("ECAM at %#llx for %04x [bus %02x-%02x] is above 4GB, ignored\n",
593 	       cfg->address, cfg->pci_segment, cfg->start_bus_number,
594 	       cfg->end_bus_number);
595 	return false;
596 }
597 
598 static int __init pci_parse_mcfg(struct acpi_table_header *header)
599 {
600 	struct acpi_table_mcfg *mcfg;
601 	struct acpi_mcfg_allocation *cfg_table, *cfg;
602 	unsigned long i;
603 	int entries;
604 
605 	if (!header)
606 		return -EINVAL;
607 
608 	mcfg = (struct acpi_table_mcfg *)header;
609 
610 	/* how many config structures do we have */
611 	free_all_mmcfg();
612 	entries = 0;
613 	i = header->length - sizeof(struct acpi_table_mcfg);
614 	while (i >= sizeof(struct acpi_mcfg_allocation)) {
615 		entries++;
616 		i -= sizeof(struct acpi_mcfg_allocation);
617 	}
618 	if (entries == 0) {
619 		pr_err("MCFG has no entries\n");
620 		return -ENODEV;
621 	}
622 
623 	cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
624 	for (i = 0; i < entries; i++) {
625 		cfg = &cfg_table[i];
626 		if (!acpi_mcfg_valid_entry(mcfg, cfg)) {
627 			free_all_mmcfg();
628 			return -ENODEV;
629 		}
630 
631 		if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
632 				   cfg->end_bus_number, cfg->address) == NULL) {
633 			pr_warn("no memory for MCFG entries\n");
634 			free_all_mmcfg();
635 			return -ENOMEM;
636 		}
637 	}
638 
639 	return 0;
640 }
641 
642 #ifdef CONFIG_ACPI_APEI
643 extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
644 				     void *data), void *data);
645 
646 static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
647 				     void *data), void *data)
648 {
649 	struct pci_mmcfg_region *cfg;
650 	int rc;
651 
652 	if (list_empty(&pci_mmcfg_list))
653 		return 0;
654 
655 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
656 		rc = func(cfg->res.start, resource_size(&cfg->res), data);
657 		if (rc)
658 			return rc;
659 	}
660 
661 	return 0;
662 }
663 #define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
664 #else
665 #define set_apei_filter()
666 #endif
667 
668 static void __init __pci_mmcfg_init(int early)
669 {
670 	pr_debug("%s(%s)\n", __func__, early ? "early" : "late");
671 
672 	pci_mmcfg_reject_broken(early);
673 	if (list_empty(&pci_mmcfg_list))
674 		return;
675 
676 	if (pcibios_last_bus < 0) {
677 		const struct pci_mmcfg_region *cfg;
678 
679 		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
680 			if (cfg->segment)
681 				break;
682 			pcibios_last_bus = cfg->end_bus;
683 		}
684 	}
685 
686 	if (pci_mmcfg_arch_init())
687 		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
688 	else {
689 		free_all_mmcfg();
690 		pci_mmcfg_arch_init_failed = true;
691 	}
692 }
693 
694 static int __initdata known_bridge;
695 
696 void __init pci_mmcfg_early_init(void)
697 {
698 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
699 
700 	if (pci_probe & PCI_PROBE_MMCONF) {
701 		if (pci_mmcfg_check_hostbridge())
702 			known_bridge = 1;
703 		else
704 			acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
705 		__pci_mmcfg_init(1);
706 
707 		set_apei_filter();
708 	}
709 }
710 
711 void __init pci_mmcfg_late_init(void)
712 {
713 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
714 
715 	/* ECAM disabled */
716 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
717 		return;
718 
719 	if (known_bridge)
720 		return;
721 
722 	/* ECAM hasn't been enabled yet, try again */
723 	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
724 		acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
725 		__pci_mmcfg_init(0);
726 	}
727 }
728 
729 static int __init pci_mmcfg_late_insert_resources(void)
730 {
731 	struct pci_mmcfg_region *cfg;
732 
733 	pci_mmcfg_running_state = true;
734 
735 	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
736 
737 	/* If we are not using ECAM, don't insert the resources. */
738 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
739 		return 1;
740 
741 	/*
742 	 * Attempt to insert the mmcfg resources but not with the busy flag
743 	 * marked so it won't cause request errors when __request_region is
744 	 * called.
745 	 */
746 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
747 		if (!cfg->res.parent) {
748 			pr_debug("%s() insert %pR\n", __func__, &cfg->res);
749 			insert_resource(&iomem_resource, &cfg->res);
750 		}
751 	}
752 
753 	return 0;
754 }
755 
756 /*
757  * Perform ECAM resource insertion after PCI initialization to allow for
758  * misprogrammed MCFG tables that state larger sizes but actually conflict
759  * with other system resources.
760  */
761 late_initcall(pci_mmcfg_late_insert_resources);
762 
763 /* Add ECAM information for host bridges */
764 int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
765 			phys_addr_t addr)
766 {
767 	int rc;
768 	struct resource *tmp = NULL;
769 	struct pci_mmcfg_region *cfg;
770 
771 	dev_dbg(dev, "%s(%04x [bus %02x-%02x])\n", __func__, seg, start, end);
772 
773 	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
774 		return -ENODEV;
775 
776 	if (start > end)
777 		return -EINVAL;
778 
779 	mutex_lock(&pci_mmcfg_lock);
780 	cfg = pci_mmconfig_lookup(seg, start);
781 	if (cfg) {
782 		if (cfg->end_bus < end)
783 			dev_info(dev, FW_INFO "ECAM %pR for domain %04x [bus %02x-%02x] only partially covers this bridge\n",
784 				 &cfg->res, cfg->segment, cfg->start_bus,
785 				 cfg->end_bus);
786 		mutex_unlock(&pci_mmcfg_lock);
787 		return -EEXIST;
788 	}
789 
790 	/*
791 	 * Don't move earlier; we must return -EEXIST, not -EINVAL, if
792 	 * pci_mmconfig_lookup() finds something
793 	 */
794 	if (!addr) {
795 		mutex_unlock(&pci_mmcfg_lock);
796 		return -EINVAL;
797 	}
798 
799 	rc = -EBUSY;
800 	cfg = pci_mmconfig_alloc(seg, start, end, addr);
801 	if (cfg == NULL) {
802 		dev_warn(dev, "fail to add ECAM (out of memory)\n");
803 		rc = -ENOMEM;
804 	} else if (!pci_mmcfg_reserved(dev, cfg, 0)) {
805 		dev_warn(dev, FW_BUG "ECAM %pR isn't reserved\n",
806 			 &cfg->res);
807 	} else {
808 		/* Insert resource if it's not in boot stage */
809 		if (pci_mmcfg_running_state)
810 			tmp = insert_resource_conflict(&iomem_resource,
811 						       &cfg->res);
812 
813 		if (tmp) {
814 			dev_warn(dev, "ECAM %pR conflicts with %s %pR\n",
815 				 &cfg->res, tmp->name, tmp);
816 		} else if (pci_mmcfg_arch_map(cfg)) {
817 			dev_warn(dev, "fail to map ECAM %pR\n", &cfg->res);
818 		} else {
819 			list_add_sorted(cfg);
820 			dev_info(dev, "ECAM %pR (base %#lx)\n",
821 				 &cfg->res, (unsigned long)addr);
822 			cfg = NULL;
823 			rc = 0;
824 		}
825 	}
826 
827 	if (cfg) {
828 		if (cfg->res.parent)
829 			release_resource(&cfg->res);
830 		kfree(cfg);
831 	}
832 
833 	mutex_unlock(&pci_mmcfg_lock);
834 
835 	return rc;
836 }
837 
838 /* Delete ECAM information for host bridges */
839 int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
840 {
841 	struct pci_mmcfg_region *cfg;
842 
843 	mutex_lock(&pci_mmcfg_lock);
844 	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
845 		if (cfg->segment == seg && cfg->start_bus == start &&
846 		    cfg->end_bus == end) {
847 			list_del_rcu(&cfg->list);
848 			synchronize_rcu();
849 			pci_mmcfg_arch_unmap(cfg);
850 			if (cfg->res.parent)
851 				release_resource(&cfg->res);
852 			mutex_unlock(&pci_mmcfg_lock);
853 			kfree(cfg);
854 			return 0;
855 		}
856 	mutex_unlock(&pci_mmcfg_lock);
857 
858 	return -ENOENT;
859 }
860