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. */
30 static bool pci_mmcfg_running_state;
31 static bool pci_mmcfg_arch_init_failed;
32 static DEFINE_MUTEX(pci_mmcfg_lock);
33 #define pci_mmcfg_lock_held() lock_is_held(&(pci_mmcfg_lock).dep_map)
34
35 LIST_HEAD(pci_mmcfg_list);
36
pci_mmconfig_remove(struct pci_mmcfg_region * cfg)37 static void __init pci_mmconfig_remove(struct pci_mmcfg_region *cfg)
38 {
39 if (cfg->res.parent)
40 release_resource(&cfg->res);
41 list_del(&cfg->list);
42 kfree(cfg);
43 }
44
free_all_mmcfg(void)45 static void __init free_all_mmcfg(void)
46 {
47 struct pci_mmcfg_region *cfg, *tmp;
48
49 pci_mmcfg_arch_free();
50 list_for_each_entry_safe(cfg, tmp, &pci_mmcfg_list, list)
51 pci_mmconfig_remove(cfg);
52 }
53
list_add_sorted(struct pci_mmcfg_region * new)54 static void list_add_sorted(struct pci_mmcfg_region *new)
55 {
56 struct pci_mmcfg_region *cfg;
57
58 /* keep list sorted by segment and starting bus number */
59 list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held()) {
60 if (cfg->segment > new->segment ||
61 (cfg->segment == new->segment &&
62 cfg->start_bus >= new->start_bus)) {
63 list_add_tail_rcu(&new->list, &cfg->list);
64 return;
65 }
66 }
67 list_add_tail_rcu(&new->list, &pci_mmcfg_list);
68 }
69
pci_mmconfig_alloc(int segment,int start,int end,u64 addr)70 static struct pci_mmcfg_region *pci_mmconfig_alloc(int segment, int start,
71 int end, u64 addr)
72 {
73 struct pci_mmcfg_region *new;
74 struct resource *res;
75
76 if (addr == 0)
77 return NULL;
78
79 new = kzalloc(sizeof(*new), GFP_KERNEL);
80 if (!new)
81 return NULL;
82
83 new->address = addr;
84 new->segment = segment;
85 new->start_bus = start;
86 new->end_bus = end;
87
88 res = &new->res;
89 res->start = addr + PCI_MMCFG_BUS_OFFSET(start);
90 res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1;
91 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
92 snprintf(new->name, PCI_MMCFG_RESOURCE_NAME_LEN,
93 "PCI MMCONFIG %04x [bus %02x-%02x]", segment, start, end);
94 res->name = new->name;
95
96 return new;
97 }
98
pci_mmconfig_add(int segment,int start,int end,u64 addr)99 struct pci_mmcfg_region *__init pci_mmconfig_add(int segment, int start,
100 int end, u64 addr)
101 {
102 struct pci_mmcfg_region *new;
103
104 new = pci_mmconfig_alloc(segment, start, end, addr);
105 if (new) {
106 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
pci_mmconfig_lookup(int segment,int bus)119 struct 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
pci_mmcfg_e7520(void)131 static 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
pci_mmcfg_intel_945(void)146 static 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
pci_mmcfg_amd_fam10h(void)190 static 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
240 static bool __initdata mcp55_checked;
pci_mmcfg_nvidia_mcp55(void)241 static 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
304 struct pci_mmcfg_hostbridge_probe {
305 u32 bus;
306 u32 devfn;
307 u32 vendor;
308 u32 device;
309 const char *(*probe)(void);
310 };
311
312 static 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
pci_mmcfg_check_end_bus_number(void)325 static 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
pci_mmcfg_check_hostbridge(void)344 static 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
check_mcfg_resource(struct acpi_resource * res,void * data)379 static 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
find_mboard_resource(acpi_handle handle,u32 lvl,void * context,void ** rv)415 static 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
is_acpi_reserved(u64 start,u64 end,enum e820_type not_used)429 static 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
is_efi_mmio(u64 start,u64 end,enum e820_type not_used)446 static 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
472 typedef bool (*check_reserved_t)(u64 start, u64 end, enum e820_type type);
473
is_mmconf_reserved(check_reserved_t is_reserved,struct pci_mmcfg_region * cfg,struct device * dev,const char * method)474 static 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
525 static bool __ref
pci_mmcfg_check_reserved(struct device * dev,struct pci_mmcfg_region * cfg,int early)526 pci_mmcfg_check_reserved(struct device *dev, struct pci_mmcfg_region *cfg, int early)
527 {
528 struct resource *conflict;
529
530 if (early) {
531
532 /*
533 * Don't try to do this check unless configuration type 1
534 * is available. How about type 2?
535 */
536
537 /*
538 * 946f2ee5c731 ("Check that MCFG points to an e820
539 * reserved area") added this E820 check in 2006 to work
540 * around BIOS defects.
541 *
542 * Per PCI Firmware r3.3, sec 4.1.2, ECAM space must be
543 * reserved by a PNP0C02 resource, but it need not be
544 * mentioned in E820. Before the ACPI interpreter is
545 * available, we can't check for PNP0C02 resources, so
546 * there's no reliable way to verify the region in this
547 * early check. Keep it only for the old machines that
548 * motivated 946f2ee5c731.
549 */
550 if (dmi_get_bios_year() < 2016 && raw_pci_ops)
551 return is_mmconf_reserved(e820__mapped_all, cfg, dev,
552 "E820 entry");
553
554 return true;
555 }
556
557 if (!acpi_disabled) {
558 if (is_mmconf_reserved(is_acpi_reserved, cfg, dev,
559 "ACPI motherboard resource"))
560 return true;
561
562 if (dev)
563 dev_info(dev, FW_INFO
564 "MMCONFIG at %pR not reserved in "
565 "ACPI motherboard resources\n",
566 &cfg->res);
567 else
568 pr_info(FW_INFO PREFIX
569 "MMCONFIG at %pR not reserved in "
570 "ACPI motherboard resources\n",
571 &cfg->res);
572
573 if (is_mmconf_reserved(is_efi_mmio, cfg, dev,
574 "EfiMemoryMappedIO")) {
575 conflict = insert_resource_conflict(&iomem_resource,
576 &cfg->res);
577 if (conflict)
578 pr_warn("MMCONFIG %pR conflicts with %s %pR\n",
579 &cfg->res, conflict->name, conflict);
580 else
581 pr_info("MMCONFIG %pR reserved to work around lack of ACPI motherboard _CRS\n",
582 &cfg->res);
583 return true;
584 }
585 }
586
587 /*
588 * e820__mapped_all() is marked as __init.
589 * All entries from ACPI MCFG table have been checked at boot time.
590 * For MCFG information constructed from hotpluggable host bridge's
591 * _CBA method, just assume it's reserved.
592 */
593 return pci_mmcfg_running_state;
594 }
595
pci_mmcfg_reject_broken(int early)596 static void __init pci_mmcfg_reject_broken(int early)
597 {
598 struct pci_mmcfg_region *cfg;
599
600 list_for_each_entry(cfg, &pci_mmcfg_list, list) {
601 if (pci_mmcfg_check_reserved(NULL, cfg, early) == 0) {
602 pr_info(PREFIX "not using MMCONFIG\n");
603 free_all_mmcfg();
604 return;
605 }
606 }
607 }
608
acpi_mcfg_check_entry(struct acpi_table_mcfg * mcfg,struct acpi_mcfg_allocation * cfg)609 static int __init acpi_mcfg_check_entry(struct acpi_table_mcfg *mcfg,
610 struct acpi_mcfg_allocation *cfg)
611 {
612 if (cfg->address < 0xFFFFFFFF)
613 return 0;
614
615 if (!strncmp(mcfg->header.oem_id, "SGI", 3))
616 return 0;
617
618 if ((mcfg->header.revision >= 1) && (dmi_get_bios_year() >= 2010))
619 return 0;
620
621 pr_err(PREFIX "MCFG region for %04x [bus %02x-%02x] at %#llx "
622 "is above 4GB, ignored\n", cfg->pci_segment,
623 cfg->start_bus_number, cfg->end_bus_number, cfg->address);
624 return -EINVAL;
625 }
626
pci_parse_mcfg(struct acpi_table_header * header)627 static int __init pci_parse_mcfg(struct acpi_table_header *header)
628 {
629 struct acpi_table_mcfg *mcfg;
630 struct acpi_mcfg_allocation *cfg_table, *cfg;
631 unsigned long i;
632 int entries;
633
634 if (!header)
635 return -EINVAL;
636
637 mcfg = (struct acpi_table_mcfg *)header;
638
639 /* how many config structures do we have */
640 free_all_mmcfg();
641 entries = 0;
642 i = header->length - sizeof(struct acpi_table_mcfg);
643 while (i >= sizeof(struct acpi_mcfg_allocation)) {
644 entries++;
645 i -= sizeof(struct acpi_mcfg_allocation);
646 }
647 if (entries == 0) {
648 pr_err(PREFIX "MMCONFIG has no entries\n");
649 return -ENODEV;
650 }
651
652 cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
653 for (i = 0; i < entries; i++) {
654 cfg = &cfg_table[i];
655 if (acpi_mcfg_check_entry(mcfg, cfg)) {
656 free_all_mmcfg();
657 return -ENODEV;
658 }
659
660 if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
661 cfg->end_bus_number, cfg->address) == NULL) {
662 pr_warn(PREFIX "no memory for MCFG entries\n");
663 free_all_mmcfg();
664 return -ENOMEM;
665 }
666 }
667
668 return 0;
669 }
670
671 #ifdef CONFIG_ACPI_APEI
672 extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
673 void *data), void *data);
674
pci_mmcfg_for_each_region(int (* func)(__u64 start,__u64 size,void * data),void * data)675 static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
676 void *data), void *data)
677 {
678 struct pci_mmcfg_region *cfg;
679 int rc;
680
681 if (list_empty(&pci_mmcfg_list))
682 return 0;
683
684 list_for_each_entry(cfg, &pci_mmcfg_list, list) {
685 rc = func(cfg->res.start, resource_size(&cfg->res), data);
686 if (rc)
687 return rc;
688 }
689
690 return 0;
691 }
692 #define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
693 #else
694 #define set_apei_filter()
695 #endif
696
__pci_mmcfg_init(int early)697 static void __init __pci_mmcfg_init(int early)
698 {
699 pci_mmcfg_reject_broken(early);
700 if (list_empty(&pci_mmcfg_list))
701 return;
702
703 if (pcibios_last_bus < 0) {
704 const struct pci_mmcfg_region *cfg;
705
706 list_for_each_entry(cfg, &pci_mmcfg_list, list) {
707 if (cfg->segment)
708 break;
709 pcibios_last_bus = cfg->end_bus;
710 }
711 }
712
713 if (pci_mmcfg_arch_init())
714 pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
715 else {
716 free_all_mmcfg();
717 pci_mmcfg_arch_init_failed = true;
718 }
719 }
720
721 static int __initdata known_bridge;
722
pci_mmcfg_early_init(void)723 void __init pci_mmcfg_early_init(void)
724 {
725 if (pci_probe & PCI_PROBE_MMCONF) {
726 if (pci_mmcfg_check_hostbridge())
727 known_bridge = 1;
728 else
729 acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
730 __pci_mmcfg_init(1);
731
732 set_apei_filter();
733 }
734 }
735
pci_mmcfg_late_init(void)736 void __init pci_mmcfg_late_init(void)
737 {
738 /* MMCONFIG disabled */
739 if ((pci_probe & PCI_PROBE_MMCONF) == 0)
740 return;
741
742 if (known_bridge)
743 return;
744
745 /* MMCONFIG hasn't been enabled yet, try again */
746 if (pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF) {
747 acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
748 __pci_mmcfg_init(0);
749 }
750 }
751
pci_mmcfg_late_insert_resources(void)752 static int __init pci_mmcfg_late_insert_resources(void)
753 {
754 struct pci_mmcfg_region *cfg;
755
756 pci_mmcfg_running_state = true;
757
758 /* If we are not using MMCONFIG, don't insert the resources. */
759 if ((pci_probe & PCI_PROBE_MMCONF) == 0)
760 return 1;
761
762 /*
763 * Attempt to insert the mmcfg resources but not with the busy flag
764 * marked so it won't cause request errors when __request_region is
765 * called.
766 */
767 list_for_each_entry(cfg, &pci_mmcfg_list, list)
768 if (!cfg->res.parent)
769 insert_resource(&iomem_resource, &cfg->res);
770
771 return 0;
772 }
773
774 /*
775 * Perform MMCONFIG 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 */
779 late_initcall(pci_mmcfg_late_insert_resources);
780
781 /* Add MMCFG information for host bridges */
pci_mmconfig_insert(struct device * dev,u16 seg,u8 start,u8 end,phys_addr_t addr)782 int 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 if (!(pci_probe & PCI_PROBE_MMCONF) || pci_mmcfg_arch_init_failed)
790 return -ENODEV;
791
792 if (start > end)
793 return -EINVAL;
794
795 mutex_lock(&pci_mmcfg_lock);
796 cfg = pci_mmconfig_lookup(seg, start);
797 if (cfg) {
798 if (cfg->end_bus < end)
799 dev_info(dev, FW_INFO
800 "MMCONFIG for "
801 "domain %04x [bus %02x-%02x] "
802 "only partially covers this bridge\n",
803 cfg->segment, cfg->start_bus, cfg->end_bus);
804 mutex_unlock(&pci_mmcfg_lock);
805 return -EEXIST;
806 }
807
808 if (!addr) {
809 mutex_unlock(&pci_mmcfg_lock);
810 return -EINVAL;
811 }
812
813 rc = -EBUSY;
814 cfg = pci_mmconfig_alloc(seg, start, end, addr);
815 if (cfg == NULL) {
816 dev_warn(dev, "fail to add MMCONFIG (out of memory)\n");
817 rc = -ENOMEM;
818 } else if (!pci_mmcfg_check_reserved(dev, cfg, 0)) {
819 dev_warn(dev, FW_BUG "MMCONFIG %pR isn't reserved\n",
820 &cfg->res);
821 } else {
822 /* Insert resource if it's not in boot stage */
823 if (pci_mmcfg_running_state)
824 tmp = insert_resource_conflict(&iomem_resource,
825 &cfg->res);
826
827 if (tmp) {
828 dev_warn(dev,
829 "MMCONFIG %pR conflicts with "
830 "%s %pR\n",
831 &cfg->res, tmp->name, tmp);
832 } else if (pci_mmcfg_arch_map(cfg)) {
833 dev_warn(dev, "fail to map MMCONFIG %pR.\n",
834 &cfg->res);
835 } else {
836 list_add_sorted(cfg);
837 dev_info(dev, "MMCONFIG at %pR (base %#lx)\n",
838 &cfg->res, (unsigned long)addr);
839 cfg = NULL;
840 rc = 0;
841 }
842 }
843
844 if (cfg) {
845 if (cfg->res.parent)
846 release_resource(&cfg->res);
847 kfree(cfg);
848 }
849
850 mutex_unlock(&pci_mmcfg_lock);
851
852 return rc;
853 }
854
855 /* Delete MMCFG information for host bridges */
pci_mmconfig_delete(u16 seg,u8 start,u8 end)856 int pci_mmconfig_delete(u16 seg, u8 start, u8 end)
857 {
858 struct pci_mmcfg_region *cfg;
859
860 mutex_lock(&pci_mmcfg_lock);
861 list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
862 if (cfg->segment == seg && cfg->start_bus == start &&
863 cfg->end_bus == end) {
864 list_del_rcu(&cfg->list);
865 synchronize_rcu();
866 pci_mmcfg_arch_unmap(cfg);
867 if (cfg->res.parent)
868 release_resource(&cfg->res);
869 mutex_unlock(&pci_mmcfg_lock);
870 kfree(cfg);
871 return 0;
872 }
873 mutex_unlock(&pci_mmcfg_lock);
874
875 return -ENOENT;
876 }
877