1 /* 2 * pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de> 7 * (c) Copyright 2008 Hewlett-Packard Development Company, L.P. 8 * Bjorn Helgaas <bjorn.helgaas@hp.com> 9 * 10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or (at 15 * your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, but 18 * WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * General Public License for more details. 21 * 22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 23 */ 24 25 26 #include <linux/dmi.h> 27 #include <linux/kernel.h> 28 #include <linux/module.h> 29 #include <linux/init.h> 30 #include <linux/types.h> 31 #include <linux/spinlock.h> 32 #include <linux/pm.h> 33 #include <linux/pci.h> 34 #include <linux/acpi.h> 35 #include <linux/slab.h> 36 #include <linux/interrupt.h> 37 38 #define PREFIX "ACPI: " 39 40 #define _COMPONENT ACPI_PCI_COMPONENT 41 ACPI_MODULE_NAME("pci_irq"); 42 43 struct acpi_prt_entry { 44 struct acpi_pci_id id; 45 u8 pin; 46 acpi_handle link; 47 u32 index; /* GSI, or link _CRS index */ 48 }; 49 50 static inline char pin_name(int pin) 51 { 52 return 'A' + pin - 1; 53 } 54 55 /* -------------------------------------------------------------------------- 56 PCI IRQ Routing Table (PRT) Support 57 -------------------------------------------------------------------------- */ 58 59 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */ 60 static const struct dmi_system_id medion_md9580[] = { 61 { 62 .ident = "Medion MD9580-F laptop", 63 .matches = { 64 DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"), 65 DMI_MATCH(DMI_PRODUCT_NAME, "A555"), 66 }, 67 }, 68 { } 69 }; 70 71 /* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */ 72 static const struct dmi_system_id dell_optiplex[] = { 73 { 74 .ident = "Dell Optiplex GX1", 75 .matches = { 76 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 77 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"), 78 }, 79 }, 80 { } 81 }; 82 83 /* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */ 84 static const struct dmi_system_id hp_t5710[] = { 85 { 86 .ident = "HP t5710", 87 .matches = { 88 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 89 DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"), 90 DMI_MATCH(DMI_BOARD_NAME, "098Ch"), 91 }, 92 }, 93 { } 94 }; 95 96 struct prt_quirk { 97 const struct dmi_system_id *system; 98 unsigned int segment; 99 unsigned int bus; 100 unsigned int device; 101 unsigned char pin; 102 const char *source; /* according to BIOS */ 103 const char *actual_source; 104 }; 105 106 #define PCI_INTX_PIN(c) (c - 'A' + 1) 107 108 /* 109 * These systems have incorrect _PRT entries. The BIOS claims the PCI 110 * interrupt at the listed segment/bus/device/pin is connected to the first 111 * link device, but it is actually connected to the second. 112 */ 113 static const struct prt_quirk prt_quirks[] = { 114 { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'), 115 "\\_SB_.PCI0.ISA_.LNKA", 116 "\\_SB_.PCI0.ISA_.LNKB"}, 117 { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'), 118 "\\_SB_.LNKB", 119 "\\_SB_.LNKA"}, 120 { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'), 121 "\\_SB_.PCI0.LNK1", 122 "\\_SB_.PCI0.LNK3"}, 123 }; 124 125 static void do_prt_fixups(struct acpi_prt_entry *entry, 126 struct acpi_pci_routing_table *prt) 127 { 128 int i; 129 const struct prt_quirk *quirk; 130 131 for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) { 132 quirk = &prt_quirks[i]; 133 134 /* All current quirks involve link devices, not GSIs */ 135 if (dmi_check_system(quirk->system) && 136 entry->id.segment == quirk->segment && 137 entry->id.bus == quirk->bus && 138 entry->id.device == quirk->device && 139 entry->pin == quirk->pin && 140 !strcmp(prt->source, quirk->source) && 141 strlen(prt->source) >= strlen(quirk->actual_source)) { 142 printk(KERN_WARNING PREFIX "firmware reports " 143 "%04x:%02x:%02x PCI INT %c connected to %s; " 144 "changing to %s\n", 145 entry->id.segment, entry->id.bus, 146 entry->id.device, pin_name(entry->pin), 147 prt->source, quirk->actual_source); 148 strcpy(prt->source, quirk->actual_source); 149 } 150 } 151 } 152 153 static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev, 154 int pin, struct acpi_pci_routing_table *prt, 155 struct acpi_prt_entry **entry_ptr) 156 { 157 int segment = pci_domain_nr(dev->bus); 158 int bus = dev->bus->number; 159 int device = pci_ari_enabled(dev->bus) ? 0 : PCI_SLOT(dev->devfn); 160 struct acpi_prt_entry *entry; 161 162 if (((prt->address >> 16) & 0xffff) != device || 163 prt->pin + 1 != pin) 164 return -ENODEV; 165 166 entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL); 167 if (!entry) 168 return -ENOMEM; 169 170 /* 171 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses 172 * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert 173 * it here. 174 */ 175 entry->id.segment = segment; 176 entry->id.bus = bus; 177 entry->id.device = (prt->address >> 16) & 0xFFFF; 178 entry->pin = prt->pin + 1; 179 180 do_prt_fixups(entry, prt); 181 182 entry->index = prt->source_index; 183 184 /* 185 * Type 1: Dynamic 186 * --------------- 187 * The 'source' field specifies the PCI interrupt link device used to 188 * configure the IRQ assigned to this slot|dev|pin. The 'source_index' 189 * indicates which resource descriptor in the resource template (of 190 * the link device) this interrupt is allocated from. 191 * 192 * NOTE: Don't query the Link Device for IRQ information at this time 193 * because Link Device enumeration may not have occurred yet 194 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI 195 * namespace). 196 */ 197 if (prt->source[0]) 198 acpi_get_handle(handle, prt->source, &entry->link); 199 200 /* 201 * Type 2: Static 202 * -------------- 203 * The 'source' field is NULL, and the 'source_index' field specifies 204 * the IRQ value, which is hardwired to specific interrupt inputs on 205 * the interrupt controller. 206 */ 207 208 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO, 209 " %04x:%02x:%02x[%c] -> %s[%d]\n", 210 entry->id.segment, entry->id.bus, 211 entry->id.device, pin_name(entry->pin), 212 prt->source, entry->index)); 213 214 *entry_ptr = entry; 215 216 return 0; 217 } 218 219 static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev, 220 int pin, struct acpi_prt_entry **entry_ptr) 221 { 222 acpi_status status; 223 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 224 struct acpi_pci_routing_table *entry; 225 acpi_handle handle = NULL; 226 227 if (dev->bus->bridge) 228 handle = ACPI_HANDLE(dev->bus->bridge); 229 230 if (!handle) 231 return -ENODEV; 232 233 /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */ 234 status = acpi_get_irq_routing_table(handle, &buffer); 235 if (ACPI_FAILURE(status)) { 236 kfree(buffer.pointer); 237 return -ENODEV; 238 } 239 240 entry = buffer.pointer; 241 while (entry && (entry->length > 0)) { 242 if (!acpi_pci_irq_check_entry(handle, dev, pin, 243 entry, entry_ptr)) 244 break; 245 entry = (struct acpi_pci_routing_table *) 246 ((unsigned long)entry + entry->length); 247 } 248 249 kfree(buffer.pointer); 250 return 0; 251 } 252 253 /* -------------------------------------------------------------------------- 254 PCI Interrupt Routing Support 255 -------------------------------------------------------------------------- */ 256 #ifdef CONFIG_X86_IO_APIC 257 extern int noioapicquirk; 258 extern int noioapicreroute; 259 260 static int bridge_has_boot_interrupt_variant(struct pci_bus *bus) 261 { 262 struct pci_bus *bus_it; 263 264 for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) { 265 if (!bus_it->self) 266 return 0; 267 if (bus_it->self->irq_reroute_variant) 268 return bus_it->self->irq_reroute_variant; 269 } 270 return 0; 271 } 272 273 /* 274 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ 275 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does 276 * during interrupt handling). When this INTx generation cannot be disabled, 277 * we reroute these interrupts to their legacy equivalent to get rid of 278 * spurious interrupts. 279 */ 280 static int acpi_reroute_boot_interrupt(struct pci_dev *dev, 281 struct acpi_prt_entry *entry) 282 { 283 if (noioapicquirk || noioapicreroute) { 284 return 0; 285 } else { 286 switch (bridge_has_boot_interrupt_variant(dev->bus)) { 287 case 0: 288 /* no rerouting necessary */ 289 return 0; 290 case INTEL_IRQ_REROUTE_VARIANT: 291 /* 292 * Remap according to INTx routing table in 6700PXH 293 * specs, intel order number 302628-002, section 294 * 2.15.2. Other chipsets (80332, ...) have the same 295 * mapping and are handled here as well. 296 */ 297 dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy " 298 "IRQ %d\n", entry->index, 299 (entry->index % 4) + 16); 300 entry->index = (entry->index % 4) + 16; 301 return 1; 302 default: 303 dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy " 304 "IRQ: unknown mapping\n", entry->index); 305 return -1; 306 } 307 } 308 } 309 #endif /* CONFIG_X86_IO_APIC */ 310 311 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) 312 { 313 struct acpi_prt_entry *entry = NULL; 314 struct pci_dev *bridge; 315 u8 bridge_pin, orig_pin = pin; 316 int ret; 317 318 ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry); 319 if (!ret && entry) { 320 #ifdef CONFIG_X86_IO_APIC 321 acpi_reroute_boot_interrupt(dev, entry); 322 #endif /* CONFIG_X86_IO_APIC */ 323 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n", 324 pci_name(dev), pin_name(pin))); 325 return entry; 326 } 327 328 /* 329 * Attempt to derive an IRQ for this device from a parent bridge's 330 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge). 331 */ 332 bridge = dev->bus->self; 333 while (bridge) { 334 pin = pci_swizzle_interrupt_pin(dev, pin); 335 336 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) { 337 /* PC card has the same IRQ as its cardbridge */ 338 bridge_pin = bridge->pin; 339 if (!bridge_pin) { 340 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 341 "No interrupt pin configured for device %s\n", 342 pci_name(bridge))); 343 return NULL; 344 } 345 pin = bridge_pin; 346 } 347 348 ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry); 349 if (!ret && entry) { 350 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 351 "Derived GSI for %s INT %c from %s\n", 352 pci_name(dev), pin_name(orig_pin), 353 pci_name(bridge))); 354 return entry; 355 } 356 357 dev = bridge; 358 bridge = dev->bus->self; 359 } 360 361 dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n", 362 pin_name(orig_pin)); 363 return NULL; 364 } 365 366 #if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA) 367 static int acpi_isa_register_gsi(struct pci_dev *dev) 368 { 369 u32 dev_gsi; 370 371 /* Interrupt Line values above 0xF are forbidden */ 372 if (dev->irq > 0 && (dev->irq <= 0xF) && 373 acpi_isa_irq_available(dev->irq) && 374 (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) { 375 dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n", 376 pin_name(dev->pin), dev->irq); 377 acpi_register_gsi(&dev->dev, dev_gsi, 378 ACPI_LEVEL_SENSITIVE, 379 ACPI_ACTIVE_LOW); 380 return 0; 381 } 382 return -EINVAL; 383 } 384 #else 385 static inline int acpi_isa_register_gsi(struct pci_dev *dev) 386 { 387 return -ENODEV; 388 } 389 #endif 390 391 static inline bool acpi_pci_irq_valid(struct pci_dev *dev, u8 pin) 392 { 393 #ifdef CONFIG_X86 394 /* 395 * On x86 irq line 0xff means "unknown" or "no connection" 396 * (PCI 3.0, Section 6.2.4, footnote on page 223). 397 */ 398 if (dev->irq == 0xff) { 399 dev->irq = IRQ_NOTCONNECTED; 400 dev_warn(&dev->dev, "PCI INT %c: not connected\n", 401 pin_name(pin)); 402 return false; 403 } 404 #endif 405 return true; 406 } 407 408 int acpi_pci_irq_enable(struct pci_dev *dev) 409 { 410 struct acpi_prt_entry *entry; 411 int gsi; 412 u8 pin; 413 int triggering = ACPI_LEVEL_SENSITIVE; 414 /* 415 * On ARM systems with the GIC interrupt model, level interrupts 416 * are always polarity high by specification; PCI legacy 417 * IRQs lines are inverted before reaching the interrupt 418 * controller and must therefore be considered active high 419 * as default. 420 */ 421 int polarity = acpi_irq_model == ACPI_IRQ_MODEL_GIC ? 422 ACPI_ACTIVE_HIGH : ACPI_ACTIVE_LOW; 423 char *link = NULL; 424 char link_desc[16]; 425 int rc; 426 427 pin = dev->pin; 428 if (!pin) { 429 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 430 "No interrupt pin configured for device %s\n", 431 pci_name(dev))); 432 return 0; 433 } 434 435 if (dev->irq_managed && dev->irq > 0) 436 return 0; 437 438 entry = acpi_pci_irq_lookup(dev, pin); 439 if (!entry) { 440 /* 441 * IDE legacy mode controller IRQs are magic. Why do compat 442 * extensions always make such a nasty mess. 443 */ 444 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE && 445 (dev->class & 0x05) == 0) 446 return 0; 447 } 448 449 if (entry) { 450 if (entry->link) 451 gsi = acpi_pci_link_allocate_irq(entry->link, 452 entry->index, 453 &triggering, &polarity, 454 &link); 455 else 456 gsi = entry->index; 457 } else 458 gsi = -1; 459 460 if (gsi < 0) { 461 /* 462 * No IRQ known to the ACPI subsystem - maybe the BIOS / 463 * driver reported one, then use it. Exit in any case. 464 */ 465 if (!acpi_pci_irq_valid(dev, pin)) 466 return 0; 467 468 if (acpi_isa_register_gsi(dev)) 469 dev_warn(&dev->dev, "PCI INT %c: no GSI\n", 470 pin_name(pin)); 471 472 kfree(entry); 473 return 0; 474 } 475 476 rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity); 477 if (rc < 0) { 478 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n", 479 pin_name(pin)); 480 kfree(entry); 481 return rc; 482 } 483 dev->irq = rc; 484 dev->irq_managed = 1; 485 486 if (link) 487 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link); 488 else 489 link_desc[0] = '\0'; 490 491 dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n", 492 pin_name(pin), link_desc, gsi, 493 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge", 494 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq); 495 496 kfree(entry); 497 return 0; 498 } 499 500 void acpi_pci_irq_disable(struct pci_dev *dev) 501 { 502 struct acpi_prt_entry *entry; 503 int gsi; 504 u8 pin; 505 506 pin = dev->pin; 507 if (!pin || !dev->irq_managed || dev->irq <= 0) 508 return; 509 510 /* Keep IOAPIC pin configuration when suspending */ 511 if (dev->dev.power.is_prepared) 512 return; 513 #ifdef CONFIG_PM 514 if (dev->dev.power.runtime_status == RPM_SUSPENDING) 515 return; 516 #endif 517 518 entry = acpi_pci_irq_lookup(dev, pin); 519 if (!entry) 520 return; 521 522 if (entry->link) 523 gsi = acpi_pci_link_free_irq(entry->link); 524 else 525 gsi = entry->index; 526 527 kfree(entry); 528 529 /* 530 * TBD: It might be worth clearing dev->irq by magic constant 531 * (e.g. PCI_UNDEFINED_IRQ). 532 */ 533 534 dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin)); 535 if (gsi >= 0) { 536 acpi_unregister_gsi(gsi); 537 dev->irq_managed = 0; 538 } 539 } 540