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 */
30static bool pci_mmcfg_running_state;
31static bool pci_mmcfg_arch_init_failed;
32static DEFINE_MUTEX(pci_mmcfg_lock);
33#define pci_mmcfg_lock_held() lock_is_held(&(pci_mmcfg_lock).dep_map)
34
35LIST_HEAD(pci_mmcfg_list);
36
37static 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
45static 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
54static 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
70static 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
99struct 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
118struct 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
130static 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
145static 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
189static 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
239static bool __initdata mcp55_checked;
240static 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
303struct pci_mmcfg_hostbridge_probe {
304	u32 bus;
305	u32 devfn;
306	u32 vendor;
307	u32 device;
308	const char *(*probe)(void);
309};
310
311static 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
324static 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
343static 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
378static 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
414static 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
428static 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
445static 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
468typedef bool (*check_reserved_t)(u64 start, u64 end, enum e820_type type);
469
470static 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
516static 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
566static 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
580static 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
598static 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
643extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
644				     void *data), void *data);
645
646static 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
668static 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
694static int __initdata known_bridge;
695
696void __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
711void __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
729static 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 */
761late_initcall(pci_mmcfg_late_insert_resources);
762
763/* Add ECAM information for host bridges */
764int 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 */
839int 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