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v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * mmconfig-shared.c - Low-level direct PCI config space access via
  4 *                     MMCONFIG - common code between 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#include <linux/pci.h>
 15#include <linux/init.h>
 16#include <linux/sfi_acpi.h>
 17#include <linux/bitmap.h>
 18#include <linux/dmi.h>
 19#include <linux/slab.h>
 20#include <linux/mutex.h>
 21#include <linux/rculist.h>
 22#include <asm/e820/api.h>
 23#include <asm/pci_x86.h>
 24#include <asm/acpi.h>
 25
 26#define PREFIX "PCI: "
 27
 28/* Indicate if the mmcfg resources have been placed into the resource table. */
 29static bool pci_mmcfg_running_state;
 30static bool pci_mmcfg_arch_init_failed;
 31static DEFINE_MUTEX(pci_mmcfg_lock);
 32#define pci_mmcfg_lock_held() lock_is_held(&(pci_mmcfg_lock).dep_map)
 33
 34LIST_HEAD(pci_mmcfg_list);
 35
 36static void __init pci_mmconfig_remove(struct pci_mmcfg_region *cfg)
 37{
 38	if (cfg->res.parent)
 39		release_resource(&cfg->res);
 40	list_del(&cfg->list);
 41	kfree(cfg);
 42}
 43
 44static void __init free_all_mmcfg(void)
 45{
 46	struct pci_mmcfg_region *cfg, *tmp;
 47
 48	pci_mmcfg_arch_free();
 49	list_for_each_entry_safe(cfg, tmp, &pci_mmcfg_list, list)
 50		pci_mmconfig_remove(cfg);
 51}
 52
 53static void list_add_sorted(struct pci_mmcfg_region *new)
 54{
 55	struct pci_mmcfg_region *cfg;
 56
 57	/* keep list sorted by segment and starting bus number */
 58	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held()) {
 59		if (cfg->segment > new->segment ||
 60		    (cfg->segment == new->segment &&
 61		     cfg->start_bus >= new->start_bus)) {
 62			list_add_tail_rcu(&new->list, &cfg->list);
 63			return;
 64		}
 65	}
 66	list_add_tail_rcu(&new->list, &pci_mmcfg_list);
 67}
 68
 69static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start,
 70						   int end, u64 addr)
 71{
 72	struct pci_mmcfg_region *new;
 73	struct resource *res;
 74
 75	if (addr == 0)
 76		return NULL;
 77
 78	new = kzalloc(sizeof(*new), GFP_KERNEL);
 79	if (!new)
 80		return NULL;
 81
 82	new->address = addr;
 83	new->segment = segment;
 84	new->start_bus = start;
 85	new->end_bus = end;
 86
 87	res = &new->res;
 88	res->start = addr + PCI_MMCFG_BUS_OFFSET(start);
 89	res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1;
 90	res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 91	snprintf(new->name, PCI_MMCFG_RESOURCE_NAME_LEN,
 92		 "PCI MMCONFIG %04x [bus %02x-%02x]", segment, start, end);
 93	res->name = new->name;
 94
 95	return new;
 96}
 97
 98struct pci_mmcfg_region *__init pci_mmconfig_add(int segment, int start,
 99						 int end, u64 addr)
100{
101	struct pci_mmcfg_region *new;
102
103	new = pci_mmconfig_alloc(segment, start, end, addr);
104	if (new) {
105		mutex_lock(&pci_mmcfg_lock);
106		list_add_sorted(new);
107		mutex_unlock(&pci_mmcfg_lock);
108
109		pr_info(PREFIX
110		       "MMCONFIG for domain %04x [bus %02x-%02x] at %pR "
111		       "(base %#lx)\n",
112		       segment, start, end, &new->res, (unsigned long)addr);
113	}
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	/* mmconfig is not enable */
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(PREFIX "%s with MMCONFIG 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, unsigned 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
445typedef bool (*check_reserved_t)(u64 start, u64 end, unsigned type);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
446
447static bool __ref is_mmconf_reserved(check_reserved_t is_reserved,
448				     struct pci_mmcfg_region *cfg,
449				     struct device *dev, int with_e820)
450{
451	u64 addr = cfg->res.start;
452	u64 size = resource_size(&cfg->res);
453	u64 old_size = size;
454	int num_buses;
455	char *method = with_e820 ? "E820" : "ACPI motherboard resources";
456
457	while (!is_reserved(addr, addr + size, E820_TYPE_RESERVED)) {
458		size >>= 1;
459		if (size < (16UL<<20))
460			break;
461	}
462
463	if (size < (16UL<<20) && size != old_size)
464		return 0;
465
466	if (dev)
467		dev_info(dev, "MMCONFIG at %pR reserved in %s\n",
468			 &cfg->res, method);
469	else
470		pr_info(PREFIX "MMCONFIG at %pR reserved in %s\n",
471		       &cfg->res, method);
472
473	if (old_size != size) {
474		/* update end_bus */
475		cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
476		num_buses = cfg->end_bus - cfg->start_bus + 1;
477		cfg->res.end = cfg->res.start +
478		    PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
479		snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
480			 "PCI MMCONFIG %04x [bus %02x-%02x]",
481			 cfg->segment, cfg->start_bus, cfg->end_bus);
482
483		if (dev)
484			dev_info(dev,
485				"MMCONFIG "
486				"at %pR (base %#lx) (size reduced!)\n",
487				&cfg->res, (unsigned long) cfg->address);
488		else
489			pr_info(PREFIX
490				"MMCONFIG for %04x [bus%02x-%02x] "
491				"at %pR (base %#lx) (size reduced!)\n",
492				cfg->segment, cfg->start_bus, cfg->end_bus,
493				&cfg->res, (unsigned long) cfg->address);
494	}
495
496	return 1;
497}
498
499static bool __ref
500pci_mmcfg_check_reserved(struct device *dev, struct pci_mmcfg_region *cfg, int early)
501{
502	if (!early && !acpi_disabled) {
503		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev, 0))
504			return 1;
 
505
506		if (dev)
507			dev_info(dev, FW_INFO
508				 "MMCONFIG at %pR not reserved in "
509				 "ACPI motherboard resources\n",
510				 &cfg->res);
511		else
512			pr_info(FW_INFO PREFIX
513			       "MMCONFIG at %pR not reserved in "
514			       "ACPI motherboard resources\n",
515			       &cfg->res);
 
 
 
 
516	}
517
518	/*
519	 * e820__mapped_all() is marked as __init.
520	 * All entries from ACPI MCFG table have been checked at boot time.
521	 * For MCFG information constructed from hotpluggable host bridge's
522	 * _CBA method, just assume it's reserved.
523	 */
524	if (pci_mmcfg_running_state)
525		return 1;
526
527	/* Don't try to do this check unless configuration
528	   type 1 is available. how about type 2 ?*/
529	if (raw_pci_ops)
530		return is_mmconf_reserved(e820__mapped_all, cfg, dev, 1);
 
531
532	return 0;
533}
534
535static void __init pci_mmcfg_reject_broken(int early)
536{
537	struct pci_mmcfg_region *cfg;
538
539	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
540		if (pci_mmcfg_check_reserved(NULL, cfg, early) == 0) {
541			pr_info(PREFIX "not using MMCONFIG\n");
542			free_all_mmcfg();
543			return;
544		}
545	}
546}
547
548static int __init acpi_mcfg_check_entry(struct acpi_table_mcfg *mcfg,
549					struct acpi_mcfg_allocation *cfg)
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) && (dmi_get_bios_year() >= 2010))
558		return 0;
559
560	pr_err(PREFIX "MCFG region for %04x [bus %02x-%02x] at %#llx "
561	       "is above 4GB, ignored\n", cfg->pci_segment,
562	       cfg->start_bus_number, cfg->end_bus_number, cfg->address);
563	return -EINVAL;
564}
565
566static int __init pci_parse_mcfg(struct acpi_table_header *header)
567{
568	struct acpi_table_mcfg *mcfg;
569	struct acpi_mcfg_allocation *cfg_table, *cfg;
570	unsigned long i;
571	int entries;
572
573	if (!header)
574		return -EINVAL;
575
576	mcfg = (struct acpi_table_mcfg *)header;
577
578	/* how many config structures do we have */
579	free_all_mmcfg();
580	entries = 0;
581	i = header->length - sizeof(struct acpi_table_mcfg);
582	while (i >= sizeof(struct acpi_mcfg_allocation)) {
583		entries++;
584		i -= sizeof(struct acpi_mcfg_allocation);
585	}
586	if (entries == 0) {
587		pr_err(PREFIX "MMCONFIG has no entries\n");
588		return -ENODEV;
589	}
590
591	cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
592	for (i = 0; i < entries; i++) {
593		cfg = &cfg_table[i];
594		if (acpi_mcfg_check_entry(mcfg, cfg)) {
595			free_all_mmcfg();
596			return -ENODEV;
597		}
598
599		if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
600				   cfg->end_bus_number, cfg->address) == NULL) {
601			pr_warn(PREFIX "no memory for MCFG entries\n");
602			free_all_mmcfg();
603			return -ENOMEM;
604		}
605	}
606
607	return 0;
608}
609
610#ifdef CONFIG_ACPI_APEI
611extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
612				     void *data), void *data);
613
614static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
615				     void *data), void *data)
616{
617	struct pci_mmcfg_region *cfg;
618	int rc;
619
620	if (list_empty(&pci_mmcfg_list))
621		return 0;
622
623	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
624		rc = func(cfg->res.start, resource_size(&cfg->res), data);
625		if (rc)
626			return rc;
627	}
628
629	return 0;
630}
631#define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
632#else
633#define set_apei_filter()
634#endif
635
636static void __init __pci_mmcfg_init(int early)
637{
638	pci_mmcfg_reject_broken(early);
639	if (list_empty(&pci_mmcfg_list))
640		return;
641
642	if (pcibios_last_bus < 0) {
643		const struct pci_mmcfg_region *cfg;
644
645		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
646			if (cfg->segment)
647				break;
648			pcibios_last_bus = cfg->end_bus;
649		}
650	}
651
652	if (pci_mmcfg_arch_init())
653		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
654	else {
655		free_all_mmcfg();
656		pci_mmcfg_arch_init_failed = true;
657	}
658}
659
660static int __initdata known_bridge;
661
662void __init pci_mmcfg_early_init(void)
663{
664	if (pci_probe & PCI_PROBE_MMCONF) {
665		if (pci_mmcfg_check_hostbridge())
666			known_bridge = 1;
667		else
668			acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
669		__pci_mmcfg_init(1);
670
671		set_apei_filter();
672	}
673}
674
675void __init pci_mmcfg_late_init(void)
676{
677	/* MMCONFIG disabled */
678	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
679		return;
680
681	if (known_bridge)
682		return;
683
684	/* MMCONFIG hasn't been enabled yet, try again */
685	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
686		acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
687		__pci_mmcfg_init(0);
688	}
689}
690
691static int __init pci_mmcfg_late_insert_resources(void)
692{
693	struct pci_mmcfg_region *cfg;
694
695	pci_mmcfg_running_state = true;
696
697	/* If we are not using MMCONFIG, don't insert the resources. */
698	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
699		return 1;
700
701	/*
702	 * Attempt to insert the mmcfg resources but not with the busy flag
703	 * marked so it won't cause request errors when __request_region is
704	 * called.
705	 */
706	list_for_each_entry(cfg, &pci_mmcfg_list, list)
707		if (!cfg->res.parent)
708			insert_resource(&iomem_resource, &cfg->res);
709
710	return 0;
711}
712
713/*
714 * Perform MMCONFIG resource insertion after PCI initialization to allow for
715 * misprogrammed MCFG tables that state larger sizes but actually conflict
716 * with other system resources.
717 */
718late_initcall(pci_mmcfg_late_insert_resources);
719
720/* Add MMCFG information for host bridges */
721int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
722			phys_addr_t addr)
723{
724	int rc;
725	struct resource *tmp = NULL;
726	struct pci_mmcfg_region *cfg;
727
728	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
729		return -ENODEV;
730
731	if (start > end)
732		return -EINVAL;
733
734	mutex_lock(&pci_mmcfg_lock);
735	cfg = pci_mmconfig_lookup(seg, start);
736	if (cfg) {
737		if (cfg->end_bus < end)
738			dev_info(dev, FW_INFO
739				 "MMCONFIG for "
740				 "domain %04x [bus %02x-%02x] "
741				 "only partially covers this bridge\n",
742				  cfg->segment, cfg->start_bus, cfg->end_bus);
743		mutex_unlock(&pci_mmcfg_lock);
744		return -EEXIST;
745	}
746
747	if (!addr) {
748		mutex_unlock(&pci_mmcfg_lock);
749		return -EINVAL;
750	}
751
752	rc = -EBUSY;
753	cfg = pci_mmconfig_alloc(seg, start, end, addr);
754	if (cfg == NULL) {
755		dev_warn(dev, "fail to add MMCONFIG (out of memory)\n");
756		rc = -ENOMEM;
757	} else if (!pci_mmcfg_check_reserved(dev, cfg, 0)) {
758		dev_warn(dev, FW_BUG "MMCONFIG %pR isn't reserved\n",
759			 &cfg->res);
760	} else {
761		/* Insert resource if it's not in boot stage */
762		if (pci_mmcfg_running_state)
763			tmp = insert_resource_conflict(&iomem_resource,
764						       &cfg->res);
765
766		if (tmp) {
767			dev_warn(dev,
768				 "MMCONFIG %pR conflicts with "
769				 "%s %pR\n",
770				 &cfg->res, tmp->name, tmp);
771		} else if (pci_mmcfg_arch_map(cfg)) {
772			dev_warn(dev, "fail to map MMCONFIG %pR.\n",
773				 &cfg->res);
774		} else {
775			list_add_sorted(cfg);
776			dev_info(dev, "MMCONFIG at %pR (base %#lx)\n",
777				 &cfg->res, (unsigned long)addr);
778			cfg = NULL;
779			rc = 0;
780		}
781	}
782
783	if (cfg) {
784		if (cfg->res.parent)
785			release_resource(&cfg->res);
786		kfree(cfg);
787	}
788
789	mutex_unlock(&pci_mmcfg_lock);
790
791	return rc;
792}
793
794/* Delete MMCFG information for host bridges */
795int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
796{
797	struct pci_mmcfg_region *cfg;
798
799	mutex_lock(&pci_mmcfg_lock);
800	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
801		if (cfg->segment == seg && cfg->start_bus == start &&
802		    cfg->end_bus == end) {
803			list_del_rcu(&cfg->list);
804			synchronize_rcu();
805			pci_mmcfg_arch_unmap(cfg);
806			if (cfg->res.parent)
807				release_resource(&cfg->res);
808			mutex_unlock(&pci_mmcfg_lock);
809			kfree(cfg);
810			return 0;
811		}
812	mutex_unlock(&pci_mmcfg_lock);
813
814	return -ENOENT;
815}
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * mmconfig-shared.c - Low-level direct PCI config space access via
  4 *                     MMCONFIG - common code between 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#include <linux/acpi.h>
 15#include <linux/efi.h>
 16#include <linux/pci.h>
 17#include <linux/init.h>
 
 18#include <linux/bitmap.h>
 19#include <linux/dmi.h>
 20#include <linux/slab.h>
 21#include <linux/mutex.h>
 22#include <linux/rculist.h>
 23#include <asm/e820/api.h>
 24#include <asm/pci_x86.h>
 25#include <asm/acpi.h>
 26
 27#define PREFIX "PCI: "
 28
 29/* Indicate if the mmcfg 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 MMCONFIG %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		mutex_lock(&pci_mmcfg_lock);
107		list_add_sorted(new);
108		mutex_unlock(&pci_mmcfg_lock);
109
110		pr_info(PREFIX
111		       "MMCONFIG for domain %04x [bus %02x-%02x] at %pR "
112		       "(base %#lx)\n",
113		       segment, start, end, &new->res, (unsigned long)addr);
114	}
115
116	return new;
117}
118
119struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus)
120{
121	struct pci_mmcfg_region *cfg;
122
123	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held())
124		if (cfg->segment == segment &&
125		    cfg->start_bus <= bus && bus <= cfg->end_bus)
126			return cfg;
127
128	return NULL;
129}
130
131static const char *__init pci_mmcfg_e7520(void)
132{
133	u32 win;
134	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0xce, 2, &win);
135
136	win = win & 0xf000;
137	if (win == 0x0000 || win == 0xf000)
138		return NULL;
139
140	if (pci_mmconfig_add(0, 0, 255, win << 16) == NULL)
141		return NULL;
142
143	return "Intel Corporation E7520 Memory Controller Hub";
144}
145
146static const char *__init pci_mmcfg_intel_945(void)
147{
148	u32 pciexbar, mask = 0, len = 0;
149
150	raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0x48, 4, &pciexbar);
151
152	/* Enable bit */
153	if (!(pciexbar & 1))
154		return NULL;
155
156	/* Size bits */
157	switch ((pciexbar >> 1) & 3) {
158	case 0:
159		mask = 0xf0000000U;
160		len  = 0x10000000U;
161		break;
162	case 1:
163		mask = 0xf8000000U;
164		len  = 0x08000000U;
165		break;
166	case 2:
167		mask = 0xfc000000U;
168		len  = 0x04000000U;
169		break;
170	default:
171		return NULL;
172	}
173
174	/* Errata #2, things break when not aligned on a 256Mb boundary */
175	/* Can only happen in 64M/128M mode */
176
177	if ((pciexbar & mask) & 0x0fffffffU)
178		return NULL;
179
180	/* Don't hit the APIC registers and their friends */
181	if ((pciexbar & mask) >= 0xf0000000U)
182		return NULL;
183
184	if (pci_mmconfig_add(0, 0, (len >> 20) - 1, pciexbar & mask) == NULL)
185		return NULL;
186
187	return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
188}
189
190static const char *__init pci_mmcfg_amd_fam10h(void)
191{
192	u32 low, high, address;
193	u64 base, msr;
194	int i;
195	unsigned segnbits = 0, busnbits, end_bus;
196
197	if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
198		return NULL;
199
200	address = MSR_FAM10H_MMIO_CONF_BASE;
201	if (rdmsr_safe(address, &low, &high))
202		return NULL;
203
204	msr = high;
205	msr <<= 32;
206	msr |= low;
207
208	/* mmconfig is not enable */
209	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
210		return NULL;
211
212	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
213
214	busnbits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
215			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
216
217	/*
218	 * only handle bus 0 ?
219	 * need to skip it
220	 */
221	if (!busnbits)
222		return NULL;
223
224	if (busnbits > 8) {
225		segnbits = busnbits - 8;
226		busnbits = 8;
227	}
228
229	end_bus = (1 << busnbits) - 1;
230	for (i = 0; i < (1 << segnbits); i++)
231		if (pci_mmconfig_add(i, 0, end_bus,
232				     base + (1<<28) * i) == NULL) {
233			free_all_mmcfg();
234			return NULL;
235		}
236
237	return "AMD Family 10h NB";
238}
239
240static bool __initdata mcp55_checked;
241static const char *__init pci_mmcfg_nvidia_mcp55(void)
242{
243	int bus;
244	int mcp55_mmconf_found = 0;
245
246	static const u32 extcfg_regnum __initconst	= 0x90;
247	static const u32 extcfg_regsize __initconst	= 4;
248	static const u32 extcfg_enable_mask __initconst	= 1 << 31;
249	static const u32 extcfg_start_mask __initconst	= 0xff << 16;
250	static const int extcfg_start_shift __initconst	= 16;
251	static const u32 extcfg_size_mask __initconst	= 0x3 << 28;
252	static const int extcfg_size_shift __initconst	= 28;
253	static const int extcfg_sizebus[] __initconst	= {
254		0x100, 0x80, 0x40, 0x20
255	};
256	static const u32 extcfg_base_mask[] __initconst	= {
257		0x7ff8, 0x7ffc, 0x7ffe, 0x7fff
258	};
259	static const int extcfg_base_lshift __initconst	= 25;
260
261	/*
262	 * do check if amd fam10h already took over
263	 */
264	if (!acpi_disabled || !list_empty(&pci_mmcfg_list) || mcp55_checked)
265		return NULL;
266
267	mcp55_checked = true;
268	for (bus = 0; bus < 256; bus++) {
269		u64 base;
270		u32 l, extcfg;
271		u16 vendor, device;
272		int start, size_index, end;
273
274		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), 0, 4, &l);
275		vendor = l & 0xffff;
276		device = (l >> 16) & 0xffff;
277
278		if (PCI_VENDOR_ID_NVIDIA != vendor || 0x0369 != device)
279			continue;
280
281		raw_pci_ops->read(0, bus, PCI_DEVFN(0, 0), extcfg_regnum,
282				  extcfg_regsize, &extcfg);
283
284		if (!(extcfg & extcfg_enable_mask))
285			continue;
286
287		size_index = (extcfg & extcfg_size_mask) >> extcfg_size_shift;
288		base = extcfg & extcfg_base_mask[size_index];
289		/* base could > 4G */
290		base <<= extcfg_base_lshift;
291		start = (extcfg & extcfg_start_mask) >> extcfg_start_shift;
292		end = start + extcfg_sizebus[size_index] - 1;
293		if (pci_mmconfig_add(0, start, end, base) == NULL)
294			continue;
295		mcp55_mmconf_found++;
296	}
297
298	if (!mcp55_mmconf_found)
299		return NULL;
300
301	return "nVidia MCP55";
302}
303
304struct pci_mmcfg_hostbridge_probe {
305	u32 bus;
306	u32 devfn;
307	u32 vendor;
308	u32 device;
309	const char *(*probe)(void);
310};
311
312static const struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initconst = {
313	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
314	  PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
315	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
316	  PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
317	{ 0, PCI_DEVFN(0x18, 0), PCI_VENDOR_ID_AMD,
318	  0x1200, pci_mmcfg_amd_fam10h },
319	{ 0xff, PCI_DEVFN(0, 0), PCI_VENDOR_ID_AMD,
320	  0x1200, pci_mmcfg_amd_fam10h },
321	{ 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_NVIDIA,
322	  0x0369, pci_mmcfg_nvidia_mcp55 },
323};
324
325static void __init pci_mmcfg_check_end_bus_number(void)
326{
327	struct pci_mmcfg_region *cfg, *cfgx;
328
329	/* Fixup overlaps */
330	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
331		if (cfg->end_bus < cfg->start_bus)
332			cfg->end_bus = 255;
333
334		/* Don't access the list head ! */
335		if (cfg->list.next == &pci_mmcfg_list)
336			break;
337
338		cfgx = list_entry(cfg->list.next, typeof(*cfg), list);
339		if (cfg->end_bus >= cfgx->start_bus)
340			cfg->end_bus = cfgx->start_bus - 1;
341	}
342}
343
344static int __init pci_mmcfg_check_hostbridge(void)
345{
346	u32 l;
347	u32 bus, devfn;
348	u16 vendor, device;
349	int i;
350	const char *name;
351
352	if (!raw_pci_ops)
353		return 0;
354
355	free_all_mmcfg();
356
357	for (i = 0; i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
358		bus =  pci_mmcfg_probes[i].bus;
359		devfn = pci_mmcfg_probes[i].devfn;
360		raw_pci_ops->read(0, bus, devfn, 0, 4, &l);
361		vendor = l & 0xffff;
362		device = (l >> 16) & 0xffff;
363
364		name = NULL;
365		if (pci_mmcfg_probes[i].vendor == vendor &&
366		    pci_mmcfg_probes[i].device == device)
367			name = pci_mmcfg_probes[i].probe();
368
369		if (name)
370			pr_info(PREFIX "%s with MMCONFIG support\n", name);
371	}
372
373	/* some end_bus_number is crazy, fix it */
374	pci_mmcfg_check_end_bus_number();
375
376	return !list_empty(&pci_mmcfg_list);
377}
378
379static acpi_status check_mcfg_resource(struct acpi_resource *res, void *data)
380{
381	struct resource *mcfg_res = data;
382	struct acpi_resource_address64 address;
383	acpi_status status;
384
385	if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
386		struct acpi_resource_fixed_memory32 *fixmem32 =
387			&res->data.fixed_memory32;
388		if (!fixmem32)
389			return AE_OK;
390		if ((mcfg_res->start >= fixmem32->address) &&
391		    (mcfg_res->end < (fixmem32->address +
392				      fixmem32->address_length))) {
393			mcfg_res->flags = 1;
394			return AE_CTRL_TERMINATE;
395		}
396	}
397	if ((res->type != ACPI_RESOURCE_TYPE_ADDRESS32) &&
398	    (res->type != ACPI_RESOURCE_TYPE_ADDRESS64))
399		return AE_OK;
400
401	status = acpi_resource_to_address64(res, &address);
402	if (ACPI_FAILURE(status) ||
403	   (address.address.address_length <= 0) ||
404	   (address.resource_type != ACPI_MEMORY_RANGE))
405		return AE_OK;
406
407	if ((mcfg_res->start >= address.address.minimum) &&
408	    (mcfg_res->end < (address.address.minimum + address.address.address_length))) {
409		mcfg_res->flags = 1;
410		return AE_CTRL_TERMINATE;
411	}
412	return AE_OK;
413}
414
415static acpi_status find_mboard_resource(acpi_handle handle, u32 lvl,
416					void *context, void **rv)
417{
418	struct resource *mcfg_res = context;
419
420	acpi_walk_resources(handle, METHOD_NAME__CRS,
421			    check_mcfg_resource, context);
422
423	if (mcfg_res->flags)
424		return AE_CTRL_TERMINATE;
425
426	return AE_OK;
427}
428
429static bool is_acpi_reserved(u64 start, u64 end, enum e820_type not_used)
430{
431	struct resource mcfg_res;
432
433	mcfg_res.start = start;
434	mcfg_res.end = end - 1;
435	mcfg_res.flags = 0;
436
437	acpi_get_devices("PNP0C01", find_mboard_resource, &mcfg_res, NULL);
438
439	if (!mcfg_res.flags)
440		acpi_get_devices("PNP0C02", find_mboard_resource, &mcfg_res,
441				 NULL);
442
443	return mcfg_res.flags;
444}
445
446static bool is_efi_mmio(u64 start, u64 end, enum e820_type not_used)
447{
448#ifdef CONFIG_EFI
449	efi_memory_desc_t *md;
450	u64 size, mmio_start, mmio_end;
451
452	for_each_efi_memory_desc(md) {
453		if (md->type == EFI_MEMORY_MAPPED_IO) {
454			size = md->num_pages << EFI_PAGE_SHIFT;
455			mmio_start = md->phys_addr;
456			mmio_end = mmio_start + size;
457
458			/*
459			 * N.B. Caller supplies (start, start + size),
460			 * so to match, mmio_end is the first address
461			 * *past* the EFI_MEMORY_MAPPED_IO area.
462			 */
463			if (mmio_start <= start && end <= mmio_end)
464				return true;
465		}
466	}
467#endif
468
469	return false;
470}
471
472typedef bool (*check_reserved_t)(u64 start, u64 end, enum e820_type type);
473
474static bool __ref is_mmconf_reserved(check_reserved_t is_reserved,
475				     struct pci_mmcfg_region *cfg,
476				     struct device *dev, const char *method)
477{
478	u64 addr = cfg->res.start;
479	u64 size = resource_size(&cfg->res);
480	u64 old_size = size;
481	int num_buses;
 
482
483	while (!is_reserved(addr, addr + size, E820_TYPE_RESERVED)) {
484		size >>= 1;
485		if (size < (16UL<<20))
486			break;
487	}
488
489	if (size < (16UL<<20) && size != old_size)
490		return false;
491
492	if (dev)
493		dev_info(dev, "MMCONFIG at %pR reserved as %s\n",
494			 &cfg->res, method);
495	else
496		pr_info(PREFIX "MMCONFIG at %pR reserved as %s\n",
497		       &cfg->res, method);
498
499	if (old_size != size) {
500		/* update end_bus */
501		cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
502		num_buses = cfg->end_bus - cfg->start_bus + 1;
503		cfg->res.end = cfg->res.start +
504		    PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
505		snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
506			 "PCI MMCONFIG %04x [bus %02x-%02x]",
507			 cfg->segment, cfg->start_bus, cfg->end_bus);
508
509		if (dev)
510			dev_info(dev,
511				"MMCONFIG "
512				"at %pR (base %#lx) (size reduced!)\n",
513				&cfg->res, (unsigned long) cfg->address);
514		else
515			pr_info(PREFIX
516				"MMCONFIG for %04x [bus%02x-%02x] "
517				"at %pR (base %#lx) (size reduced!)\n",
518				cfg->segment, cfg->start_bus, cfg->end_bus,
519				&cfg->res, (unsigned long) cfg->address);
520	}
521
522	return true;
523}
524
525static bool __ref
526pci_mmcfg_check_reserved(struct device *dev, struct pci_mmcfg_region *cfg, int early)
527{
528	if (!early && !acpi_disabled) {
529		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev,
530				       "ACPI motherboard resource"))
531			return true;
532
533		if (dev)
534			dev_info(dev, FW_INFO
535				 "MMCONFIG at %pR not reserved in "
536				 "ACPI motherboard resources\n",
537				 &cfg->res);
538		else
539			pr_info(FW_INFO PREFIX
540			       "MMCONFIG at %pR not reserved in "
541			       "ACPI motherboard resources\n",
542			       &cfg->res);
543
544		if (is_mmconf_reserved(is_efi_mmio, cfg, dev,
545				       "EfiMemoryMappedIO"))
546			return true;
547	}
548
549	/*
550	 * e820__mapped_all() is marked as __init.
551	 * All entries from ACPI MCFG table have been checked at boot time.
552	 * For MCFG information constructed from hotpluggable host bridge's
553	 * _CBA method, just assume it's reserved.
554	 */
555	if (pci_mmcfg_running_state)
556		return true;
557
558	/* Don't try to do this check unless configuration
559	   type 1 is available. how about type 2 ?*/
560	if (raw_pci_ops)
561		return is_mmconf_reserved(e820__mapped_all, cfg, dev,
562					  "E820 entry");
563
564	return false;
565}
566
567static void __init pci_mmcfg_reject_broken(int early)
568{
569	struct pci_mmcfg_region *cfg;
570
571	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
572		if (pci_mmcfg_check_reserved(NULL, cfg, early) == 0) {
573			pr_info(PREFIX "not using MMCONFIG\n");
574			free_all_mmcfg();
575			return;
576		}
577	}
578}
579
580static int __init acpi_mcfg_check_entry(struct acpi_table_mcfg *mcfg,
581					struct acpi_mcfg_allocation *cfg)
582{
583	if (cfg->address < 0xFFFFFFFF)
584		return 0;
585
586	if (!strncmp(mcfg->header.oem_id, "SGI", 3))
587		return 0;
588
589	if ((mcfg->header.revision >= 1) && (dmi_get_bios_year() >= 2010))
590		return 0;
591
592	pr_err(PREFIX "MCFG region for %04x [bus %02x-%02x] at %#llx "
593	       "is above 4GB, ignored\n", cfg->pci_segment,
594	       cfg->start_bus_number, cfg->end_bus_number, cfg->address);
595	return -EINVAL;
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(PREFIX "MMCONFIG 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_check_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(PREFIX "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	pci_mmcfg_reject_broken(early);
671	if (list_empty(&pci_mmcfg_list))
672		return;
673
674	if (pcibios_last_bus < 0) {
675		const struct pci_mmcfg_region *cfg;
676
677		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
678			if (cfg->segment)
679				break;
680			pcibios_last_bus = cfg->end_bus;
681		}
682	}
683
684	if (pci_mmcfg_arch_init())
685		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
686	else {
687		free_all_mmcfg();
688		pci_mmcfg_arch_init_failed = true;
689	}
690}
691
692static int __initdata known_bridge;
693
694void __init pci_mmcfg_early_init(void)
695{
696	if (pci_probe & PCI_PROBE_MMCONF) {
697		if (pci_mmcfg_check_hostbridge())
698			known_bridge = 1;
699		else
700			acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
701		__pci_mmcfg_init(1);
702
703		set_apei_filter();
704	}
705}
706
707void __init pci_mmcfg_late_init(void)
708{
709	/* MMCONFIG disabled */
710	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
711		return;
712
713	if (known_bridge)
714		return;
715
716	/* MMCONFIG hasn't been enabled yet, try again */
717	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
718		acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
719		__pci_mmcfg_init(0);
720	}
721}
722
723static int __init pci_mmcfg_late_insert_resources(void)
724{
725	struct pci_mmcfg_region *cfg;
726
727	pci_mmcfg_running_state = true;
728
729	/* If we are not using MMCONFIG, don't insert the resources. */
730	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
731		return 1;
732
733	/*
734	 * Attempt to insert the mmcfg resources but not with the busy flag
735	 * marked so it won't cause request errors when __request_region is
736	 * called.
737	 */
738	list_for_each_entry(cfg, &pci_mmcfg_list, list)
739		if (!cfg->res.parent)
740			insert_resource(&iomem_resource, &cfg->res);
741
742	return 0;
743}
744
745/*
746 * Perform MMCONFIG resource insertion after PCI initialization to allow for
747 * misprogrammed MCFG tables that state larger sizes but actually conflict
748 * with other system resources.
749 */
750late_initcall(pci_mmcfg_late_insert_resources);
751
752/* Add MMCFG information for host bridges */
753int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
754			phys_addr_t addr)
755{
756	int rc;
757	struct resource *tmp = NULL;
758	struct pci_mmcfg_region *cfg;
759
760	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
761		return -ENODEV;
762
763	if (start > end)
764		return -EINVAL;
765
766	mutex_lock(&pci_mmcfg_lock);
767	cfg = pci_mmconfig_lookup(seg, start);
768	if (cfg) {
769		if (cfg->end_bus < end)
770			dev_info(dev, FW_INFO
771				 "MMCONFIG for "
772				 "domain %04x [bus %02x-%02x] "
773				 "only partially covers this bridge\n",
774				  cfg->segment, cfg->start_bus, cfg->end_bus);
775		mutex_unlock(&pci_mmcfg_lock);
776		return -EEXIST;
777	}
778
779	if (!addr) {
780		mutex_unlock(&pci_mmcfg_lock);
781		return -EINVAL;
782	}
783
784	rc = -EBUSY;
785	cfg = pci_mmconfig_alloc(seg, start, end, addr);
786	if (cfg == NULL) {
787		dev_warn(dev, "fail to add MMCONFIG (out of memory)\n");
788		rc = -ENOMEM;
789	} else if (!pci_mmcfg_check_reserved(dev, cfg, 0)) {
790		dev_warn(dev, FW_BUG "MMCONFIG %pR isn't reserved\n",
791			 &cfg->res);
792	} else {
793		/* Insert resource if it's not in boot stage */
794		if (pci_mmcfg_running_state)
795			tmp = insert_resource_conflict(&iomem_resource,
796						       &cfg->res);
797
798		if (tmp) {
799			dev_warn(dev,
800				 "MMCONFIG %pR conflicts with "
801				 "%s %pR\n",
802				 &cfg->res, tmp->name, tmp);
803		} else if (pci_mmcfg_arch_map(cfg)) {
804			dev_warn(dev, "fail to map MMCONFIG %pR.\n",
805				 &cfg->res);
806		} else {
807			list_add_sorted(cfg);
808			dev_info(dev, "MMCONFIG at %pR (base %#lx)\n",
809				 &cfg->res, (unsigned long)addr);
810			cfg = NULL;
811			rc = 0;
812		}
813	}
814
815	if (cfg) {
816		if (cfg->res.parent)
817			release_resource(&cfg->res);
818		kfree(cfg);
819	}
820
821	mutex_unlock(&pci_mmcfg_lock);
822
823	return rc;
824}
825
826/* Delete MMCFG information for host bridges */
827int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
828{
829	struct pci_mmcfg_region *cfg;
830
831	mutex_lock(&pci_mmcfg_lock);
832	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
833		if (cfg->segment == seg && cfg->start_bus == start &&
834		    cfg->end_bus == end) {
835			list_del_rcu(&cfg->list);
836			synchronize_rcu();
837			pci_mmcfg_arch_unmap(cfg);
838			if (cfg->res.parent)
839				release_resource(&cfg->res);
840			mutex_unlock(&pci_mmcfg_lock);
841			kfree(cfg);
842			return 0;
843		}
844	mutex_unlock(&pci_mmcfg_lock);
845
846	return -ENOENT;
847}