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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}
v6.9.4
  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) {
522
523		/*
524		 * Don't try to do this check unless configuration type 1
525		 * is available.  How about type 2?
526		 */
527
528		/*
529		 * 946f2ee5c731 ("Check that MCFG points to an e820
530		 * reserved area") added this E820 check in 2006 to work
531		 * around BIOS defects.
532		 *
533		 * Per PCI Firmware r3.3, sec 4.1.2, ECAM space must be
534		 * reserved by a PNP0C02 resource, but it need not be
535		 * mentioned in E820.  Before the ACPI interpreter is
536		 * available, we can't check for PNP0C02 resources, so
537		 * there's no reliable way to verify the region in this
538		 * early check.  Keep it only for the old machines that
539		 * motivated 946f2ee5c731.
540		 */
541		if (dmi_get_bios_year() < 2016 && raw_pci_ops)
542			return is_mmconf_reserved(e820__mapped_all, cfg, dev,
543						  "E820 entry");
544
545		return true;
546	}
547
548	if (!acpi_disabled) {
549		if (is_mmconf_reserved(is_acpi_reserved, cfg, dev,
550				       "ACPI motherboard resource"))
551			return true;
552
553		if (dev)
554			dev_info(dev, FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
 
 
555				 &cfg->res);
556		else
557			pr_info(FW_INFO "ECAM %pR not reserved in ACPI motherboard resources\n",
558			        &cfg->res);
559
560		if (is_efi_mmio(&cfg->res)) {
561			pr_info("ECAM %pR is EfiMemoryMappedIO; assuming valid\n",
562				&cfg->res);
563			conflict = insert_resource_conflict(&iomem_resource,
564							    &cfg->res);
565			if (conflict)
566				pr_warn("ECAM %pR conflicts with %s %pR\n",
567					&cfg->res, conflict->name, conflict);
568			else
569				pr_info("ECAM %pR reserved to work around lack of ACPI motherboard _CRS\n",
570					&cfg->res);
571			return true;
572		}
573	}
574
575	/*
576	 * e820__mapped_all() is marked as __init.
577	 * All entries from ACPI MCFG table have been checked at boot time.
578	 * For MCFG information constructed from hotpluggable host bridge's
579	 * _CBA method, just assume it's reserved.
580	 */
581	return pci_mmcfg_running_state;
 
 
 
 
 
 
 
 
582}
583
584static void __init pci_mmcfg_reject_broken(int early)
585{
586	struct pci_mmcfg_region *cfg;
587
588	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
589		if (!pci_mmcfg_reserved(NULL, cfg, early)) {
590			pr_info("not using ECAM (%pR not reserved)\n",
591				&cfg->res);
592			free_all_mmcfg();
593			return;
594		}
595	}
596}
597
598static bool __init acpi_mcfg_valid_entry(struct acpi_table_mcfg *mcfg,
599					 struct acpi_mcfg_allocation *cfg)
600{
601	if (cfg->address < 0xFFFFFFFF)
602		return true;
603
604	if (!strncmp(mcfg->header.oem_id, "SGI", 3))
605		return true;
606
607	if ((mcfg->header.revision >= 1) && (dmi_get_bios_year() >= 2010))
608		return true;
609
610	pr_err("ECAM at %#llx for %04x [bus %02x-%02x] is above 4GB, ignored\n",
611	       cfg->address, cfg->pci_segment, cfg->start_bus_number,
612	       cfg->end_bus_number);
613	return false;
614}
615
616static int __init pci_parse_mcfg(struct acpi_table_header *header)
617{
618	struct acpi_table_mcfg *mcfg;
619	struct acpi_mcfg_allocation *cfg_table, *cfg;
620	unsigned long i;
621	int entries;
622
623	if (!header)
624		return -EINVAL;
625
626	mcfg = (struct acpi_table_mcfg *)header;
627
628	/* how many config structures do we have */
629	free_all_mmcfg();
630	entries = 0;
631	i = header->length - sizeof(struct acpi_table_mcfg);
632	while (i >= sizeof(struct acpi_mcfg_allocation)) {
633		entries++;
634		i -= sizeof(struct acpi_mcfg_allocation);
635	}
636	if (entries == 0) {
637		pr_err("MCFG has no entries\n");
638		return -ENODEV;
639	}
640
641	cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
642	for (i = 0; i < entries; i++) {
643		cfg = &cfg_table[i];
644		if (!acpi_mcfg_valid_entry(mcfg, cfg)) {
645			free_all_mmcfg();
646			return -ENODEV;
647		}
648
649		if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
650				   cfg->end_bus_number, cfg->address) == NULL) {
651			pr_warn("no memory for MCFG entries\n");
652			free_all_mmcfg();
653			return -ENOMEM;
654		}
655	}
656
657	return 0;
658}
659
660#ifdef CONFIG_ACPI_APEI
661extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
662				     void *data), void *data);
663
664static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
665				     void *data), void *data)
666{
667	struct pci_mmcfg_region *cfg;
668	int rc;
669
670	if (list_empty(&pci_mmcfg_list))
671		return 0;
672
673	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
674		rc = func(cfg->res.start, resource_size(&cfg->res), data);
675		if (rc)
676			return rc;
677	}
678
679	return 0;
680}
681#define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
682#else
683#define set_apei_filter()
684#endif
685
686static void __init __pci_mmcfg_init(int early)
687{
688	pr_debug("%s(%s)\n", __func__, early ? "early" : "late");
689
690	pci_mmcfg_reject_broken(early);
691	if (list_empty(&pci_mmcfg_list))
692		return;
693
694	if (pcibios_last_bus < 0) {
695		const struct pci_mmcfg_region *cfg;
696
697		list_for_each_entry(cfg, &pci_mmcfg_list, list) {
698			if (cfg->segment)
699				break;
700			pcibios_last_bus = cfg->end_bus;
701		}
702	}
703
704	if (pci_mmcfg_arch_init())
705		pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
706	else {
707		free_all_mmcfg();
708		pci_mmcfg_arch_init_failed = true;
709	}
710}
711
712static int __initdata known_bridge;
713
714void __init pci_mmcfg_early_init(void)
715{
716	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
717
718	if (pci_probe & PCI_PROBE_MMCONF) {
719		if (pci_mmcfg_check_hostbridge())
720			known_bridge = 1;
721		else
722			acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
723		__pci_mmcfg_init(1);
724
725		set_apei_filter();
726	}
727}
728
729void __init pci_mmcfg_late_init(void)
730{
731	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
732
733	/* ECAM disabled */
734	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
735		return;
736
737	if (known_bridge)
738		return;
739
740	/* ECAM hasn't been enabled yet, try again */
741	if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
742		acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
743		__pci_mmcfg_init(0);
744	}
745}
746
747static int __init pci_mmcfg_late_insert_resources(void)
748{
749	struct pci_mmcfg_region *cfg;
750
751	pci_mmcfg_running_state = true;
752
753	pr_debug("%s() pci_probe %#x\n", __func__, pci_probe);
754
755	/* If we are not using ECAM, don't insert the resources. */
756	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
757		return 1;
758
759	/*
760	 * Attempt to insert the mmcfg resources but not with the busy flag
761	 * marked so it won't cause request errors when __request_region is
762	 * called.
763	 */
764	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
765		if (!cfg->res.parent) {
766			pr_debug("%s() insert %pR\n", __func__, &cfg->res);
767			insert_resource(&iomem_resource, &cfg->res);
768		}
769	}
770
771	return 0;
772}
773
774/*
775 * Perform ECAM resource insertion after PCI initialization to allow for
776 * misprogrammed MCFG tables that state larger sizes but actually conflict
777 * with other system resources.
778 */
779late_initcall(pci_mmcfg_late_insert_resources);
780
781/* Add ECAM information for host bridges */
782int pci_mmconfig_insert(struct device *dev, u16 seg, u8 start, u8 end,
783			phys_addr_t addr)
784{
785	int rc;
786	struct resource *tmp = NULL;
787	struct pci_mmcfg_region *cfg;
788
789	dev_dbg(dev, "%s(%04x [bus %02x-%02x])\n", __func__, seg, start, end);
790
791	if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
792		return -ENODEV;
793
794	if (start > end)
795		return -EINVAL;
796
797	mutex_lock(&pci_mmcfg_lock);
798	cfg = pci_mmconfig_lookup(seg, start);
799	if (cfg) {
800		if (cfg->end_bus < end)
801			dev_info(dev, FW_INFO "ECAM %pR for domain %04x [bus %02x-%02x] only partially covers this bridge\n",
802				 &cfg->res, cfg->segment, cfg->start_bus,
803				 cfg->end_bus);
 
 
804		mutex_unlock(&pci_mmcfg_lock);
805		return -EEXIST;
806	}
807
808	/*
809	 * Don't move earlier; we must return -EEXIST, not -EINVAL, if
810	 * pci_mmconfig_lookup() finds something
811	 */
812	if (!addr) {
813		mutex_unlock(&pci_mmcfg_lock);
814		return -EINVAL;
815	}
816
817	rc = -EBUSY;
818	cfg = pci_mmconfig_alloc(seg, start, end, addr);
819	if (cfg == NULL) {
820		dev_warn(dev, "fail to add ECAM (out of memory)\n");
821		rc = -ENOMEM;
822	} else if (!pci_mmcfg_reserved(dev, cfg, 0)) {
823		dev_warn(dev, FW_BUG "ECAM %pR isn't reserved\n",
824			 &cfg->res);
825	} else {
826		/* Insert resource if it's not in boot stage */
827		if (pci_mmcfg_running_state)
828			tmp = insert_resource_conflict(&iomem_resource,
829						       &cfg->res);
830
831		if (tmp) {
832			dev_warn(dev, "ECAM %pR conflicts with %s %pR\n",
 
 
833				 &cfg->res, tmp->name, tmp);
834		} else if (pci_mmcfg_arch_map(cfg)) {
835			dev_warn(dev, "fail to map ECAM %pR\n", &cfg->res);
 
836		} else {
837			list_add_sorted(cfg);
838			dev_info(dev, "ECAM %pR (base %#lx)\n",
839				 &cfg->res, (unsigned long)addr);
840			cfg = NULL;
841			rc = 0;
842		}
843	}
844
845	if (cfg) {
846		if (cfg->res.parent)
847			release_resource(&cfg->res);
848		kfree(cfg);
849	}
850
851	mutex_unlock(&pci_mmcfg_lock);
852
853	return rc;
854}
855
856/* Delete ECAM information for host bridges */
857int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
858{
859	struct pci_mmcfg_region *cfg;
860
861	mutex_lock(&pci_mmcfg_lock);
862	list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
863		if (cfg->segment == seg && cfg->start_bus == start &&
864		    cfg->end_bus == end) {
865			list_del_rcu(&cfg->list);
866			synchronize_rcu();
867			pci_mmcfg_arch_unmap(cfg);
868			if (cfg->res.parent)
869				release_resource(&cfg->res);
870			mutex_unlock(&pci_mmcfg_lock);
871			kfree(cfg);
872			return 0;
873		}
874	mutex_unlock(&pci_mmcfg_lock);
875
876	return -ENOENT;
877}