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 (dmi_check_system(quirk->system) &&
 135                     entry->id.segment == quirk->segment &&
 136                     entry->id.bus == quirk->bus &&
 137                     entry->id.device == quirk->device &&
 138                     entry->pin == quirk->pin &&
 139                     !strcmp(prt->source, quirk->source) &&
 140                     strlen(prt->source) >= strlen(quirk->actual_source)) {
 141                         printk(KERN_WARNING PREFIX "firmware reports "
 142                                 "%04x:%02x:%02x PCI INT %c connected to %s; "
 143                                 "changing to %s\n",
 144                                 entry->id.segment, entry->id.bus,
 145                                 entry->id.device, pin_name(entry->pin),
 146                                 prt->source, quirk->actual_source);
 147                         strcpy(prt->source, quirk->actual_source);
 148                 }
 149         }
 150 }
 151
 152 static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
 153                                   int pin, struct acpi_pci_routing_table *prt,
 154                                   struct acpi_prt_entry **entry_ptr)
 155 {
 156         int segment = pci_domain_nr(dev->bus);
 157         int bus = dev->bus->number;
 158         int device = pci_ari_enabled(dev->bus) ? 0 : PCI_SLOT(dev->devfn);
 159         struct acpi_prt_entry *entry;
 160
 161         if (((prt->address >> 16) & 0xffff) != device ||
 162             prt->pin + 1 != pin)
 163                 return -ENODEV;
 164
 165         entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
 166         if (!entry)
 167                 return -ENOMEM;
 168
 169         /*
 170          * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
 171          * 1=INTA, 2=INTB.  We use the PCI encoding throughout, so convert
 172          * it here.
 173          */
 174         entry->id.segment = segment;
 175         entry->id.bus = bus;
 176         entry->id.device = (prt->address >> 16) & 0xFFFF;
 177         entry->pin = prt->pin + 1;
 178
 179         do_prt_fixups(entry, prt);
 180
 181         entry->index = prt->source_index;
 182
 183         /*
 184          * Type 1: Dynamic
 185          * ---------------
 186          * The 'source' field specifies the PCI interrupt link device used to
 187          * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
 188          * indicates which resource descriptor in the resource template (of
 189          * the link device) this interrupt is allocated from.
 190          *
 191          * NOTE: Don't query the Link Device for IRQ information at this time
 192          *       because Link Device enumeration may not have occurred yet
 193          *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
 194          *       namespace).
 195          */
 196         if (prt->source[0])
 197                 acpi_get_handle(handle, prt->source, &entry->link);
 198
 199         /*
 200          * Type 2: Static
 201          * --------------
 202          * The 'source' field is NULL, and the 'source_index' field specifies
 203          * the IRQ value, which is hardwired to specific interrupt inputs on
 204          * the interrupt controller.
 205          */
 206
 207         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
 208                               "      %04x:%02x:%02x[%c] -> %s[%d]\n",
 209                               entry->id.segment, entry->id.bus,
 210                               entry->id.device, pin_name(entry->pin),
 211                               prt->source, entry->index));
 212
 213         *entry_ptr = entry;
 214
 215         return 0;
 216 }
 217
 218 static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
 219                           int pin, struct acpi_prt_entry **entry_ptr)
 220 {
 221         acpi_status status;
 222         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 223         struct acpi_pci_routing_table *entry;
 224         acpi_handle handle = NULL;
 225
 226         if (dev->bus->bridge)
 227                 handle = ACPI_HANDLE(dev->bus->bridge);
 228
 229         if (!handle)
 230                 return -ENODEV;
 231
 232         /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
 233         status = acpi_get_irq_routing_table(handle, &buffer);
 234         if (ACPI_FAILURE(status)) {
 235                 kfree(buffer.pointer);
 236                 return -ENODEV;
 237         }
 238
 239         entry = buffer.pointer;
 240         while (entry && (entry->length > 0)) {
 241                 if (!acpi_pci_irq_check_entry(handle, dev, pin,
 242                                                  entry, entry_ptr))
 243                         break;
 244                 entry = (struct acpi_pci_routing_table *)
 245                     ((unsigned long)entry + entry->length);
 246         }
 247
 248         kfree(buffer.pointer);
 249         return 0;
 250 }
 251
 252 /* --------------------------------------------------------------------------
 253                           PCI Interrupt Routing Support
 254    -------------------------------------------------------------------------- */
 255 #ifdef CONFIG_X86_IO_APIC
 256 extern int noioapicquirk;
 257 extern int noioapicreroute;
 258
 259 static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
 260 {
 261         struct pci_bus *bus_it;
 262
 263         for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
 264                 if (!bus_it->self)
 265                         return 0;
 266                 if (bus_it->self->irq_reroute_variant)
 267                         return bus_it->self->irq_reroute_variant;
 268         }
 269         return 0;
 270 }
 271
 272 /*
 273  * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
 274  * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
 275  * during interrupt handling). When this INTx generation cannot be disabled,
 276  * we reroute these interrupts to their legacy equivalent to get rid of
 277  * spurious interrupts.
 278  */
 279 static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
 280                                        struct acpi_prt_entry *entry)
 281 {
 282         if (noioapicquirk || noioapicreroute) {
 283                 return 0;
 284         } else {
 285                 switch (bridge_has_boot_interrupt_variant(dev->bus)) {
 286                 case 0:
 287                         /* no rerouting necessary */
 288                         return 0;
 289                 case INTEL_IRQ_REROUTE_VARIANT:
 290                         /*
 291                          * Remap according to INTx routing table in 6700PXH
 292                          * specs, intel order number 302628-002, section
 293                          * 2.15.2. Other chipsets (80332, ...) have the same
 294                          * mapping and are handled here as well.
 295                          */
 296                         dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
 297                                  "IRQ %d\n", entry->index,
 298                                  (entry->index % 4) + 16);
 299                         entry->index = (entry->index % 4) + 16;
 300                         return 1;
 301                 default:
 302                         dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
 303                                  "IRQ: unknown mapping\n", entry->index);
 304                         return -1;
 305                 }
 306         }
 307 }
 308 #endif /* CONFIG_X86_IO_APIC */
 309
 310 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 311 {
 312         struct acpi_prt_entry *entry = NULL;
 313         struct pci_dev *bridge;
 314         u8 bridge_pin, orig_pin = pin;
 315         int ret;
 316
 317         ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
 318         if (!ret && entry) {
 319 #ifdef CONFIG_X86_IO_APIC
 320                 acpi_reroute_boot_interrupt(dev, entry);
 321 #endif /* CONFIG_X86_IO_APIC */
 322                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n",
 323                                   pci_name(dev), pin_name(pin)));
 324                 return entry;
 325         }
 326
 327         /*
 328          * Attempt to derive an IRQ for this device from a parent bridge's
 329          * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
 330          */
 331         bridge = dev->bus->self;
 332         while (bridge) {
 333                 pin = pci_swizzle_interrupt_pin(dev, pin);
 334
 335                 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
 336                         /* PC card has the same IRQ as its cardbridge */
 337                         bridge_pin = bridge->pin;
 338                         if (!bridge_pin) {
 339                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 340                                                   "No interrupt pin configured for device %s\n",
 341                                                   pci_name(bridge)));
 342                                 return NULL;
 343                         }
 344                         pin = bridge_pin;
 345                 }
 346
 347                 ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
 348                 if (!ret && entry) {
 349                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 350                                          "Derived GSI for %s INT %c from %s\n",
 351                                          pci_name(dev), pin_name(orig_pin),
 352                                          pci_name(bridge)));
 353                         return entry;
 354                 }
 355
 356                 dev = bridge;
 357                 bridge = dev->bus->self;
 358         }
 359
 360         dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
 361                  pin_name(orig_pin));
 362         return NULL;
 363 }
 364
 365 #if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
 366 static int acpi_isa_register_gsi(struct pci_dev *dev)
 367 {
 368         u32 dev_gsi;
 369
 370         /* Interrupt Line values above 0xF are forbidden */
 371         if (dev->irq > 0 && (dev->irq <= 0xF) &&
 372             acpi_isa_irq_available(dev->irq) &&
 373             (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
 374                 dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",
 375                          pin_name(dev->pin), dev->irq);
 376                 acpi_register_gsi(&dev->dev, dev_gsi,
 377                                   ACPI_LEVEL_SENSITIVE,
 378                                   ACPI_ACTIVE_LOW);
 379                 return 0;
 380         }
 381         return -EINVAL;
 382 }
 383 #else
 384 static inline int acpi_isa_register_gsi(struct pci_dev *dev)
 385 {
 386         return -ENODEV;
 387 }
 388 #endif
 389
 390 int acpi_pci_irq_enable(struct pci_dev *dev)
 391 {
 392         struct acpi_prt_entry *entry;
 393         int gsi;
 394         u8 pin;
 395         int triggering = ACPI_LEVEL_SENSITIVE;
 396         int polarity = ACPI_ACTIVE_LOW;
 397         char *link = NULL;
 398         char link_desc[16];
 399         int rc;
 400
 401         pin = dev->pin;
 402         if (!pin) {
 403                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 404                                   "No interrupt pin configured for device %s\n",
 405                                   pci_name(dev)));
 406                 return 0;
 407         }
 408
 409         if (dev->irq_managed && dev->irq > 0)
 410                 return 0;
 411
 412         entry = acpi_pci_irq_lookup(dev, pin);
 413         if (!entry) {
 414                 /*
 415                  * IDE legacy mode controller IRQs are magic. Why do compat
 416                  * extensions always make such a nasty mess.
 417                  */
 418                 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
 419                                 (dev->class & 0x05) == 0)
 420                         return 0;
 421         }
 422
 423         if (entry) {
 424                 if (entry->link)
 425                         gsi = acpi_pci_link_allocate_irq(entry->link,
 426                                                          entry->index,
 427                                                          &triggering, &polarity,
 428                                                          &link);
 429                 else
 430                         gsi = entry->index;
 431         } else
 432                 gsi = -1;
 433
 434         /*
 435          * No IRQ known to the ACPI subsystem - maybe the BIOS /
 436          * driver reported one, then use it. Exit in any case.
 437          */
 438         if (gsi < 0) {
 439                 if (acpi_isa_register_gsi(dev))
 440                         dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
 441                                  pin_name(pin));
 442
 443                 kfree(entry);
 444                 return 0;
 445         }
 446
 447         rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
 448         if (rc < 0) {
 449                 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
 450                          pin_name(pin));
 451                 kfree(entry);
 452                 return rc;
 453         }
 454         dev->irq = rc;
 455         dev->irq_managed = 1;
 456
 457         if (link)
 458                 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
 459         else
 460                 link_desc[0] = '\0';
 461
 462         dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
 463                 pin_name(pin), link_desc, gsi,
 464                 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
 465                 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
 466
 467         kfree(entry);
 468         return 0;
 469 }
 470
 471 void acpi_pci_irq_disable(struct pci_dev *dev)
 472 {
 473         struct acpi_prt_entry *entry;
 474         int gsi;
 475         u8 pin;
 476
 477         pin = dev->pin;
 478         if (!pin || !dev->irq_managed || dev->irq <= 0)
 479                 return;
 480
 481         entry = acpi_pci_irq_lookup(dev, pin);
 482         if (!entry)
 483                 return;
 484
 485         if (entry->link)
 486                 gsi = acpi_pci_link_free_irq(entry->link);
 487         else
 488                 gsi = entry->index;
 489
 490         kfree(entry);
 491
 492         /*
 493          * TBD: It might be worth clearing dev->irq by magic constant
 494          * (e.g. PCI_UNDEFINED_IRQ).
 495          */
 496
 497         dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
 498         if (gsi >= 0) {
 499                 acpi_unregister_gsi(gsi);
 500                 dev->irq_managed = 0;
 501                 dev->irq = 0;
 502         }
 503 }