1/*
2 * mmconfig-shared.c - Low-level direct PCI config space access via
3 *                     MMCONFIG - common code between i386 and x86-64.
4 *
5 * This code does:
6 * - known chipset handling
7 * - ACPI decoding and validation
8 *
9 * Per-architecture code takes care of the mappings and accesses
10 * themselves.
11 */
12
13#include <linux/pci.h>
14#include <linux/init.h>
15#include <linux/sfi_acpi.h>
16#include <linux/bitmap.h>
17#include <linux/dmi.h>
18#include <linux/slab.h>
19#include <linux/mutex.h>
20#include <linux/rculist.h>
21#include <asm/e820.h>
22#include <asm/pci_x86.h>
23#include <asm/acpi.h>
24
25#define PREFIX "PCI: "
26
27/* Indicate if the mmcfg resources have been placed into the resource table. */
28static bool pci_mmcfg_running_state;
29static bool pci_mmcfg_arch_init_failed;
30static DEFINE_MUTEX(pci_mmcfg_lock);
31
32LIST_HEAD(pci_mmcfg_list);
33
34static void __init pci_mmconfig_remove(struct pci_mmcfg_region *cfg)
35{
36	if (cfg->res.parent)
37		release_resource(&cfg->res);
38	list_del(&cfg->list);
39	kfree(cfg);
40}
41
42static void __init free_all_mmcfg(void)
43{
44	struct pci_mmcfg_region *cfg, *tmp;
45
46	pci_mmcfg_arch_free();
47	list_for_each_entry_safe(cfg, tmp, &pci_mmcfg_list, list)
48		pci_mmconfig_remove(cfg);
49}
50
51static void list_add_sorted(struct pci_mmcfg_region *new)
52{
53	struct pci_mmcfg_region *cfg;
54
55	/* keep list sorted by segment and starting bus number */
56	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) {
57		if (cfg->segment > new->segment ||
58		    (cfg->segment == new->segment &&
59		     cfg->start_bus >= new->start_bus)) {
60			list_add_tail_rcu(&new->list, &cfg->list);
61			return;
62		}
63	}
64	list_add_tail_rcu(&new->list, &pci_mmcfg_list);
65}
66
67static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start,
68						   int end, u64 addr)
69{
70	struct pci_mmcfg_region *new;
71	struct resource *res;
72
73	if (addr == 0)
74		return NULL;
75
76	new = kzalloc(sizeof(*new), GFP_KERNEL);
77	if (!new)
78		return NULL;
79
80	new->address = addr;
81	new->segment = segment;
82	new->start_bus = start;
83	new->end_bus = end;
84
85	res = &new->res;
86	res->start = addr + PCI_MMCFG_BUS_OFFSET(start);
87	res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1;
88	res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
89	snprintf(new->name, PCI_MMCFG_RESOURCE_NAME_LEN,
90		 "PCI MMCONFIG %04x [bus %02x-%02x]", segment, start, end);
91	res->name = new->name;
92
93	return new;
94}
95
96static struct pci_mmcfg_region *__init pci_mmconfig_add(int segment, int start,
97							int end, u64 addr)
98{
99	struct pci_mmcfg_region *new;
100
101	new = pci_mmconfig_alloc(segment, start, end, addr);
102	if (new) {
103		mutex_lock(&pci_mmcfg_lock);
104		list_add_sorted(new);
105		mutex_unlock(&pci_mmcfg_lock);
106
107		pr_info(PREFIX
108		       "MMCONFIG for domain %04x [bus %02x-%02x] at %pR "
109		       "(base %#lx)\n",
110		       segment, start, end, &new->res, (unsigned long)addr);
111	}
112
113	return new;
114}
115
116struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus)
117{
118	struct pci_mmcfg_region *cfg;
119
120	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
121		if (cfg->segment == segment &&
122		    cfg->start_bus <= bus && bus <= cfg->end_bus)
123			return cfg;
124
125	return NULL;
126}
127
128static const char *__init pci_mmcfg_e7520(void)
129{
130	u32 win;
131	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0xce, 2, &win);
132
133	win = win & 0xf000;
134	if (win == 0x0000 || win == 0xf000)
135		return NULL;
136
137	if (pci_mmconfig_add(0, 0, 255, win << 16) == NULL)
138		return NULL;
139
140	return "Intel Corporation E7520 Memory Controller Hub";
141}
142
143static const char *__init pci_mmcfg_intel_945(void)
144{
145	u32 pciexbar, mask = 0, len = 0;
146
147	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0x48, 4, &pciexbar);
148
149	/* Enable bit */
150	if (!(pciexbar & 1))
151		return NULL;
152
153	/* Size bits */
154	switch ((pciexbar >> 1) & 3) {
155	case 0:
156		mask = 0xf0000000U;
157		len  = 0x10000000U;
158		break;
159	case 1:
160		mask = 0xf8000000U;
161		len  = 0x08000000U;
162		break;
163	case 2:
164		mask = 0xfc000000U;
165		len  = 0x04000000U;
166		break;
167	default:
168		return NULL;
169	}
170
171	/* Errata #2, things break when not aligned on a 256Mb boundary */
172	/* Can only happen in 64M/128M mode */
173
174	if ((pciexbar & mask) & 0x0fffffffU)
175		return NULL;
176
177	/* Don't hit the APIC registers and their friends */
178	if ((pciexbar & mask) >= 0xf0000000U)
179		return NULL;
180
181	if (pci_mmconfig_add(0, 0, (len >> 20) - 1, pciexbar & mask) == NULL)
182		return NULL;
183
184	return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
185}
186
187static const char *__init pci_mmcfg_amd_fam10h(void)
188{
189	u32 low, high, address;
190	u64 base, msr;
191	int i;
192	unsigned segnbits = 0, busnbits, end_bus;
193
194	if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
195		return NULL;
196
197	address = MSR_FAM10H_MMIO_CONF_BASE;
198	if (rdmsr_safe(address, &low, &high))
199		return NULL;
200
201	msr = high;
202	msr <<= 32;
203	msr |= low;
204
205	/* mmconfig is not enable */
206	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
207		return NULL;
208
209	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
210
211	busnbits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
212			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
213
214	/*
215	 * only handle bus 0 ?
216	 * need to skip it
217	 */
218	if (!busnbits)
219		return NULL;
220
221	if (busnbits > 8) {
222		segnbits = busnbits - 8;
223		busnbits = 8;
224	}
225
226	end_bus = (1 << busnbits) - 1;
227	for (i = 0; i < (1 << segnbits); i++)
228		if (pci_mmconfig_add(i, 0, end_bus,
229				     base + (1<<28) * i) == NULL) {
230			free_all_mmcfg();
231			return NULL;
232		}
233
234	return "AMD Family 10h NB";
235}
236
237static bool __initdata mcp55_checked;
238static const char *__init pci_mmcfg_nvidia_mcp55(void)
239{
240	int bus;
241	int mcp55_mmconf_found = 0;
242
243	static const u32 extcfg_regnum __initconst	= 0x90;
244	static const u32 extcfg_regsize __initconst	= 4;
245	static const u32 extcfg_enable_mask __initconst	= 1 << 31;
246	static const u32 extcfg_start_mask __initconst	= 0xff << 16;
247	static const int extcfg_start_shift __initconst	= 16;
248	static const u32 extcfg_size_mask __initconst	= 0x3 << 28;
249	static const int extcfg_size_shift __initconst	= 28;
250	static const int extcfg_sizebus[] __initconst	= {
251		0x100, 0x80, 0x40, 0x20
252	};
253	static const u32 extcfg_base_mask[] __initconst	= {
254		0x7ff8, 0x7ffc, 0x7ffe, 0x7fff
255	};
256	static const int extcfg_base_lshift __initconst	= 25;
257
258	/*
259	 * do check if amd fam10h already took over
260	 */
261	if (!acpi_disabled || !list_empty(&pci_mmcfg_list) || mcp55_checked)
262		return NULL;
263
264	mcp55_checked = true;
265	for (bus = 0; bus < 256; bus++) {
266		u64 base;
267		u32 l, extcfg;
268		u16 vendor, device;
269		int start, size_index, end;
270
271		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), 0, 4, &l);
272		vendor = l & 0xffff;
273		device = (l >> 16) & 0xffff;
274
275		if (PCI_VENDOR_ID_NVIDIA != vendor || 0x0369 != device)
276			continue;
277
278		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), extcfg_regnum,
279				  extcfg_regsize, &extcfg);
280
281		if (!(extcfg & extcfg_enable_mask))
282			continue;
283
284		size_index = (extcfg & extcfg_size_mask) >> extcfg_size_shift;
285		base = extcfg & extcfg_base_mask[size_index];
286		/* base could > 4G */
287		base <<= extcfg_base_lshift;
288		start = (extcfg & extcfg_start_mask) >> extcfg_start_shift;
289		end = start + extcfg_sizebus[size_index] - 1;
290		if (pci_mmconfig_add(0, start, end, base) == NULL)
291			continue;
292		mcp55_mmconf_found++;
293	}
294
295	if (!mcp55_mmconf_found)
296		return NULL;
297
298	return "nVidia MCP55";
299}
300
301struct pci_mmcfg_hostbridge_probe {
302	u32 bus;
303	u32 devfn;
304	u32 vendor;
305	u32 device;
306	const char *(*probe)(void);
307};
308
309static const struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initconst = {
310	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
311	  PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
312	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
313	  PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
314	{ 0, PCI_DEVFN(0x18, 0), PCI_VENDOR_ID_AMD,
315	  0x1200, pci_mmcfg_amd_fam10h },
316	{ 0xff, PCI_DEVFN(0, 0), PCI_VENDOR_ID_AMD,
317	  0x1200, pci_mmcfg_amd_fam10h },
318	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_NVIDIA,
319	  0x0369, pci_mmcfg_nvidia_mcp55 },
320};
321
322static void __init pci_mmcfg_check_end_bus_number(void)
323{
324	struct pci_mmcfg_region *cfg, *cfgx;
325
326	/* Fixup overlaps */
327	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
328		if (cfg->end_bus < cfg->start_bus)
329			cfg->end_bus = 255;
330
331		/* Don't access the list head ! */
332		if (cfg->list.next == &pci_mmcfg_list)
333			break;
334
335		cfgx = list_entry(cfg->list.next, typeof(*cfg), list);
336		if (cfg->end_bus >= cfgx->start_bus)
337			cfg->end_bus = cfgx->start_bus - 1;
338	}
339}
340
341static int __init pci_mmcfg_check_hostbridge(void)
342{
343	u32 l;
344	u32 bus, devfn;
345	u16 vendor, device;
346	int i;
347	const char *name;
348
349	if (!raw_pci_ops)
350		return 0;
351
352	free_all_mmcfg();
353
354	for (i = 0; i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
355		bus =  pci_mmcfg_probes[i].bus;
356		devfn = pci_mmcfg_probes[i].devfn;
357		raw_pci_ops->read(0, bus, devfn, 0, 4, &l);
358		vendor = l & 0xffff;
359		device = (l >> 16) & 0xffff;
360
361		name = NULL;
362		if (pci_mmcfg_probes[i].vendor == vendor &&
363		    pci_mmcfg_probes[i].device == device)
364			name = pci_mmcfg_probes[i].probe();
365
366		if (name)
367			pr_info(PREFIX "%s with MMCONFIG support\n", name);
368	}
369
370	/* some end_bus_number is crazy, fix it */
371	pci_mmcfg_check_end_bus_number();
372
373	return !list_empty(&pci_mmcfg_list);
374}
375
376static acpi_status check_mcfg_resource(struct acpi_resource *res, void *data)
377{
378	struct resource *mcfg_res = data;
379	struct acpi_resource_address64 address;
380	acpi_status status;
381
382	if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
383		struct acpi_resource_fixed_memory32 *fixmem32 =
384			&res->data.fixed_memory32;
385		if (!fixmem32)
386			return AE_OK;
387		if ((mcfg_res->start >= fixmem32->address) &&
388		    (mcfg_res->end < (fixmem32->address +
389				      fixmem32->address_length))) {
390			mcfg_res->flags = 1;
391			return AE_CTRL_TERMINATE;
392		}
393	}
394	if ((res->type != ACPI_RESOURCE_TYPE_ADDRESS32) &&
395	    (res->type != ACPI_RESOURCE_TYPE_ADDRESS64))
396		return AE_OK;
397
398	status = acpi_resource_to_address64(res, &address);
399	if (ACPI_FAILURE(status) ||
400	   (address.address.address_length <= 0) ||
401	   (address.resource_type != ACPI_MEMORY_RANGE))
402		return AE_OK;
403
404	if ((mcfg_res->start >= address.address.minimum) &&
405	    (mcfg_res->end < (address.address.minimum + address.address.address_length))) {
406		mcfg_res->flags = 1;
407		return AE_CTRL_TERMINATE;
408	}
409	return AE_OK;
410}
411
412static acpi_status find_mboard_resource(acpi_handle handle, u32 lvl,
413					void *context, void **rv)
414{
415	struct resource *mcfg_res = context;
416
417	acpi_walk_resources(handle, METHOD_NAME__CRS,
418			    check_mcfg_resource, context);
419
420	if (mcfg_res->flags)
421		return AE_CTRL_TERMINATE;
422
423	return AE_OK;
424}
425
426static int is_acpi_reserved(u64 start, u64 end, unsigned not_used)
427{
428	struct resource mcfg_res;
429
430	mcfg_res.start = start;
431	mcfg_res.end = end - 1;
432	mcfg_res.flags = 0;
433
434	acpi_get_devices("PNP0C01", find_mboard_resource, &mcfg_res, NULL);
435
436	if (!mcfg_res.flags)
437		acpi_get_devices("PNP0C02", find_mboard_resource, &mcfg_res,
438				 NULL);
439
440	return mcfg_res.flags;
441}
442
443typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
444
445static int __ref is_mmconf_reserved(check_reserved_t is_reserved,
446				    struct pci_mmcfg_region *cfg,
447				    struct device *dev, int with_e820)
448{
449	u64 addr = cfg->res.start;
450	u64 size = resource_size(&cfg->res);
451	u64 old_size = size;
452	int num_buses;
453	char *method = with_e820 ? "E820" : "ACPI motherboard resources";
454
455	while (!is_reserved(addr, addr + size, E820_RESERVED)) {
456		size >>= 1;
457		if (size < (16UL<<20))
458			break;
459	}
460
461	if (size < (16UL<<20) && size != old_size)
462		return 0;
463
464	if (dev)
465		dev_info(dev, "MMCONFIG at %pR reserved in %s\n",
466			 &cfg->res, method);
467	else
468		pr_info(PREFIX "MMCONFIG at %pR reserved in %s\n",
469		       &cfg->res, method);
470
471	if (old_size != size) {
472		/* update end_bus */
473		cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
474		num_buses = cfg->end_bus - cfg->start_bus + 1;
475		cfg->res.end = cfg->res.start +
476		    PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
477		snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
478			 "PCI MMCONFIG %04x [bus %02x-%02x]",
479			 cfg->segment, cfg->start_bus, cfg->end_bus);
480
481		if (dev)
482			dev_info(dev,
483				"MMCONFIG "
484				"at %pR (base %#lx) (size reduced!)\n",
485				&cfg->res, (unsigned long) cfg->address);
486		else
487			pr_info(PREFIX
488				"MMCONFIG for %04x [bus%02x-%02x] "
489				"at %pR (base %#lx) (size reduced!)\n",
490				cfg->segment, cfg->start_bus, cfg->end_bus,
491				&cfg->res, (unsigned long) cfg->address);
492	}
493
494	return 1;
495}
496
497static int __ref pci_mmcfg_check_reserved(struct device *dev,
498		  struct pci_mmcfg_region *cfg, int early)
499{
500	if (!early && !acpi_disabled) {
501		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev, 0))
502			return 1;
503
504		if (dev)
505			dev_info(dev, FW_INFO
506				 "MMCONFIG at %pR not reserved in "
507				 "ACPI motherboard resources\n",
508				 &cfg->res);
509		else
510			pr_info(FW_INFO PREFIX
511			       "MMCONFIG at %pR not reserved in "
512			       "ACPI motherboard resources\n",
513			       &cfg->res);
514	}
515
516	/*
517	 * e820_all_mapped() is marked as __init.
518	 * All entries from ACPI MCFG table have been checked at boot time.
519	 * For MCFG information constructed from hotpluggable host bridge's
520	 * _CBA method, just assume it's reserved.
521	 */
522	if (pci_mmcfg_running_state)
523		return 1;
524
525	/* Don't try to do this check unless configuration
526	   type 1 is available. how about type 2 ?*/
527	if (raw_pci_ops)
528		return is_mmconf_reserved(e820_all_mapped, cfg, dev, 1);
529
530	return 0;
531}
532
533static void __init pci_mmcfg_reject_broken(int early)
534{
535	struct pci_mmcfg_region *cfg;
536
537	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
538		if (pci_mmcfg_check_reserved(NULL, cfg, early) == 0) {
539			pr_info(PREFIX "not using MMCONFIG\n");
540			free_all_mmcfg();
541			return;
542		}
543	}
544}
545
546static int __init acpi_mcfg_check_entry(struct acpi_table_mcfg *mcfg,
547					struct acpi_mcfg_allocation *cfg)
548{
549	int year;
550
551	if (cfg->address < 0xFFFFFFFF)
552		return 0;
553
554	if (!strncmp(mcfg->header.oem_id, "SGI", 3))
555		return 0;
556
557	if (mcfg->header.revision >= 1) {
558		if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) &&
559		    year >= 2010)
560			return 0;
561	}
562
563	pr_err(PREFIX "MCFG region for %04x [bus %02x-%02x] at %#llx "
564	       "is above 4GB, ignored\n", cfg->pci_segment,
565	       cfg->start_bus_number, cfg->end_bus_number, cfg->address);
566	return -EINVAL;
567}
568
569static int __init pci_parse_mcfg(struct acpi_table_header *header)
570{
571	struct acpi_table_mcfg *mcfg;
572	struct acpi_mcfg_allocation *cfg_table, *cfg;
573	unsigned long i;
574	int entries;
575
576	if (!header)
577		return -EINVAL;
578
579	mcfg = (struct acpi_table_mcfg *)header;
580
581	/* how many config structures do we have */
582	free_all_mmcfg();
583	entries = 0;
584	i = header->length - sizeof(struct acpi_table_mcfg);
585	while (i >= sizeof(struct acpi_mcfg_allocation)) {
586		entries++;
587		i -= sizeof(struct acpi_mcfg_allocation);
588	}
589	if (entries == 0) {
590		pr_err(PREFIX "MMCONFIG has no entries\n");
591		return -ENODEV;
592	}
593
594	cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
595	for (i = 0; i < entries; i++) {
596		cfg = &cfg_table[i];
597		if (acpi_mcfg_check_entry(mcfg, cfg)) {
598			free_all_mmcfg();
599			return -ENODEV;
600		}
601
602		if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
603				   cfg->end_bus_number, cfg->address) == NULL) {
604			pr_warn(PREFIX "no memory for MCFG entries\n");
605			free_all_mmcfg();
606			return -ENOMEM;
607		}
608	}
609
610	return 0;
611}
612
613#ifdef CONFIG_ACPI_APEI
614extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
615				     void *data), void *data);
616
617static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
618				     void *data), void *data)
619{
620	struct pci_mmcfg_region *cfg;
621	int rc;
622
623	if (list_empty(&pci_mmcfg_list))
624		return 0;
625
626	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
627		rc = func(cfg->res.start, resource_size(&cfg->res), data);
628		if (rc)
629			return rc;
630	}
631
632	return 0;
633}
634#define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
635#else
636#define set_apei_filter()
637#endif
638
639static void __init __pci_mmcfg_init(int early)
640{
641	pci_mmcfg_reject_broken(early);
642	if (list_empty(&pci_mmcfg_list))
643		return;
644
645	if (pcibios_last_bus < 0) {
646		const struct pci_mmcfg_region *cfg;
647
648		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
649			if (cfg->segment)
650				break;
651			pcibios_last_bus = cfg->end_bus;
652		}
653	}
654
655	if (pci_mmcfg_arch_init())
656		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
657	else {
658		free_all_mmcfg();
659		pci_mmcfg_arch_init_failed = true;
660	}
661}
662
663static int __initdata known_bridge;
664
665void __init pci_mmcfg_early_init(void)
666{
667	if (pci_probe & PCI_PROBE_MMCONF) {
668		if (pci_mmcfg_check_hostbridge())
669			known_bridge = 1;
670		else
671			acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
672		__pci_mmcfg_init(1);
673
674		set_apei_filter();
675	}
676}
677
678void __init pci_mmcfg_late_init(void)
679{
680	/* MMCONFIG disabled */
681	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
682		return;
683
684	if (known_bridge)
685		return;
686
687	/* MMCONFIG hasn't been enabled yet, try again */
688	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
689		acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
690		__pci_mmcfg_init(0);
691	}
692}
693
694static int __init pci_mmcfg_late_insert_resources(void)
695{
696	struct pci_mmcfg_region *cfg;
697
698	pci_mmcfg_running_state = true;
699
700	/* If we are not using MMCONFIG, don't insert the resources. */
701	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
702		return 1;
703
704	/*
705	 * Attempt to insert the mmcfg resources but not with the busy flag
706	 * marked so it won't cause request errors when __request_region is
707	 * called.
708	 */
709	list_for_each_entry(cfg, &pci_mmcfg_list, list)
710		if (!cfg->res.parent)
711			insert_resource(&iomem_resource, &cfg->res);
712
713	return 0;
714}
715
716/*
717 * Perform MMCONFIG resource insertion after PCI initialization to allow for
718 * misprogrammed MCFG tables that state larger sizes but actually conflict
719 * with other system resources.
720 */
721late_initcall(pci_mmcfg_late_insert_resources);
722
723/* Add MMCFG information for host bridges */
724int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
725			phys_addr_t addr)
726{
727	int rc;
728	struct resource *tmp = NULL;
729	struct pci_mmcfg_region *cfg;
730
731	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
732		return -ENODEV;
733
734	if (start > end)
735		return -EINVAL;
736
737	mutex_lock(&pci_mmcfg_lock);
738	cfg = pci_mmconfig_lookup(seg, start);
739	if (cfg) {
740		if (cfg->end_bus < end)
741			dev_info(dev, FW_INFO
742				 "MMCONFIG for "
743				 "domain %04x [bus %02x-%02x] "
744				 "only partially covers this bridge\n",
745				  cfg->segment, cfg->start_bus, cfg->end_bus);
746		mutex_unlock(&pci_mmcfg_lock);
747		return -EEXIST;
748	}
749
750	if (!addr) {
751		mutex_unlock(&pci_mmcfg_lock);
752		return -EINVAL;
753	}
754
755	rc = -EBUSY;
756	cfg = pci_mmconfig_alloc(seg, start, end, addr);
757	if (cfg == NULL) {
758		dev_warn(dev, "fail to add MMCONFIG (out of memory)\n");
759		rc = -ENOMEM;
760	} else if (!pci_mmcfg_check_reserved(dev, cfg, 0)) {
761		dev_warn(dev, FW_BUG "MMCONFIG %pR isn't reserved\n",
762			 &cfg->res);
763	} else {
764		/* Insert resource if it's not in boot stage */
765		if (pci_mmcfg_running_state)
766			tmp = insert_resource_conflict(&iomem_resource,
767						       &cfg->res);
768
769		if (tmp) {
770			dev_warn(dev,
771				 "MMCONFIG %pR conflicts with "
772				 "%s %pR\n",
773				 &cfg->res, tmp->name, tmp);
774		} else if (pci_mmcfg_arch_map(cfg)) {
775			dev_warn(dev, "fail to map MMCONFIG %pR.\n",
776				 &cfg->res);
777		} else {
778			list_add_sorted(cfg);
779			dev_info(dev, "MMCONFIG at %pR (base %#lx)\n",
780				 &cfg->res, (unsigned long)addr);
781			cfg = NULL;
782			rc = 0;
783		}
784	}
785
786	if (cfg) {
787		if (cfg->res.parent)
788			release_resource(&cfg->res);
789		kfree(cfg);
790	}
791
792	mutex_unlock(&pci_mmcfg_lock);
793
794	return rc;
795}
796
797/* Delete MMCFG information for host bridges */
798int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
799{
800	struct pci_mmcfg_region *cfg;
801
802	mutex_lock(&pci_mmcfg_lock);
803	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
804		if (cfg->segment == seg && cfg->start_bus == start &&
805		    cfg->end_bus == end) {
806			list_del_rcu(&cfg->list);
807			synchronize_rcu();
808			pci_mmcfg_arch_unmap(cfg);
809			if (cfg->res.parent)
810				release_resource(&cfg->res);
811			mutex_unlock(&pci_mmcfg_lock);
812			kfree(cfg);
813			return 0;
814		}
815	mutex_unlock(&pci_mmcfg_lock);
816
817	return -ENOENT;
818}
819