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