drivers/acpi/pci_irq.c

   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 }