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  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29
  30 #include <linux/dmi.h>
  31 #include <linux/kernel.h>
  32 #include <linux/module.h>
  33 #include <linux/init.h>
  34 #include <linux/types.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/pm.h>
  37 #include <linux/pci.h>
  38 #include <linux/acpi.h>
  39 #include <linux/slab.h>
  40 #include <acpi/acpi_bus.h>
  41 #include <acpi/acpi_drivers.h>
  42
  43 #define PREFIX "ACPI: "
  44
  45 #define _COMPONENT              ACPI_PCI_COMPONENT
  46 ACPI_MODULE_NAME("pci_irq");
  47
  48 struct acpi_prt_entry {
  49         struct list_head        list;
  50         struct acpi_pci_id      id;
  51         u8                      pin;
  52         acpi_handle             link;
  53         u32                     index;          /* GSI, or link _CRS index */
  54 };
  55
  56 static LIST_HEAD(acpi_prt_list);
  57 static DEFINE_SPINLOCK(acpi_prt_lock);
  58
  59 static inline char pin_name(int pin)
  60 {
  61         return 'A' + pin - 1;
  62 }
  63
  64 /* --------------------------------------------------------------------------
  65                          PCI IRQ Routing Table (PRT) Support
  66    -------------------------------------------------------------------------- */
  67
  68 static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
  69                                                           int pin)
  70 {
  71         struct acpi_prt_entry *entry;
  72         int segment = pci_domain_nr(dev->bus);
  73         int bus = dev->bus->number;
  74         int device = PCI_SLOT(dev->devfn);
  75
  76         spin_lock(&acpi_prt_lock);
  77         list_for_each_entry(entry, &acpi_prt_list, list) {
  78                 if ((segment == entry->id.segment)
  79                     && (bus == entry->id.bus)
  80                     && (device == entry->id.device)
  81                     && (pin == entry->pin)) {
  82                         spin_unlock(&acpi_prt_lock);
  83                         return entry;
  84                 }
  85         }
  86         spin_unlock(&acpi_prt_lock);
  87         return NULL;
  88 }
  89
  90 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
  91 static const struct dmi_system_id medion_md9580[] = {
  92         {
  93                 .ident = "Medion MD9580-F laptop",
  94                 .matches = {
  95                         DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
  96                         DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
  97                 },
  98         },
  99         { }
 100 };
 101
 102 /* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
 103 static const struct dmi_system_id dell_optiplex[] = {
 104         {
 105                 .ident = "Dell Optiplex GX1",
 106                 .matches = {
 107                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 108                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
 109                 },
 110         },
 111         { }
 112 };
 113
 114 /* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
 115 static const struct dmi_system_id hp_t5710[] = {
 116         {
 117                 .ident = "HP t5710",
 118                 .matches = {
 119                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 120                         DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
 121                         DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
 122                 },
 123         },
 124         { }
 125 };
 126
 127 struct prt_quirk {
 128         const struct dmi_system_id *system;
 129         unsigned int            segment;
 130         unsigned int            bus;
 131         unsigned int            device;
 132         unsigned char           pin;
 133         const char              *source;        /* according to BIOS */
 134         const char              *actual_source;
 135 };
 136
 137 #define PCI_INTX_PIN(c)         (c - 'A' + 1)
 138
 139 /*
 140  * These systems have incorrect _PRT entries.  The BIOS claims the PCI
 141  * interrupt at the listed segment/bus/device/pin is connected to the first
 142  * link device, but it is actually connected to the second.
 143  */
 144 static const struct prt_quirk prt_quirks[] = {
 145         { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
 146                 "\\_SB_.PCI0.ISA_.LNKA",
 147                 "\\_SB_.PCI0.ISA_.LNKB"},
 148         { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
 149                 "\\_SB_.LNKB",
 150                 "\\_SB_.LNKA"},
 151         { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
 152                 "\\_SB_.PCI0.LNK1",
 153                 "\\_SB_.PCI0.LNK3"},
 154 };
 155
 156 static void do_prt_fixups(struct acpi_prt_entry *entry,
 157                           struct acpi_pci_routing_table *prt)
 158 {
 159         int i;
 160         const struct prt_quirk *quirk;
 161
 162         for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
 163                 quirk = &prt_quirks[i];
 164
 165                 /* All current quirks involve link devices, not GSIs */
 166                 if (!prt->source)
 167                         continue;
 168
 169                 if (dmi_check_system(quirk->system) &&
 170                     entry->id.segment == quirk->segment &&
 171                     entry->id.bus == quirk->bus &&
 172                     entry->id.device == quirk->device &&
 173                     entry->pin == quirk->pin &&
 174                     !strcmp(prt->source, quirk->source) &&
 175                     strlen(prt->source) >= strlen(quirk->actual_source)) {
 176                         printk(KERN_WARNING PREFIX "firmware reports "
 177                                 "%04x:%02x:%02x PCI INT %c connected to %s; "
 178                                 "changing to %s\n",
 179                                 entry->id.segment, entry->id.bus,
 180                                 entry->id.device, pin_name(entry->pin),
 181                                 prt->source, quirk->actual_source);
 182                         strcpy(prt->source, quirk->actual_source);
 183                 }
 184         }
 185 }
 186
 187 static int acpi_pci_irq_add_entry(acpi_handle handle, struct pci_bus *bus,
 188                                   struct acpi_pci_routing_table *prt)
 189 {
 190         struct acpi_prt_entry *entry;
 191
 192         entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
 193         if (!entry)
 194                 return -ENOMEM;
 195
 196         /*
 197          * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
 198          * 1=INTA, 2=INTB.  We use the PCI encoding throughout, so convert
 199          * it here.
 200          */
 201         entry->id.segment = pci_domain_nr(bus);
 202         entry->id.bus = bus->number;
 203         entry->id.device = (prt->address >> 16) & 0xFFFF;
 204         entry->pin = prt->pin + 1;
 205
 206         do_prt_fixups(entry, prt);
 207
 208         entry->index = prt->source_index;
 209
 210         /*
 211          * Type 1: Dynamic
 212          * ---------------
 213          * The 'source' field specifies the PCI interrupt link device used to
 214          * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
 215          * indicates which resource descriptor in the resource template (of
 216          * the link device) this interrupt is allocated from.
 217          *
 218          * NOTE: Don't query the Link Device for IRQ information at this time
 219          *       because Link Device enumeration may not have occurred yet
 220          *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
 221          *       namespace).
 222          */
 223         if (prt->source[0])
 224                 acpi_get_handle(handle, prt->source, &entry->link);
 225
 226         /*
 227          * Type 2: Static
 228          * --------------
 229          * The 'source' field is NULL, and the 'source_index' field specifies
 230          * the IRQ value, which is hardwired to specific interrupt inputs on
 231          * the interrupt controller.
 232          */
 233
 234         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
 235                               "      %04x:%02x:%02x[%c] -> %s[%d]\n",
 236                               entry->id.segment, entry->id.bus,
 237                               entry->id.device, pin_name(entry->pin),
 238                               prt->source, entry->index));
 239
 240         spin_lock(&acpi_prt_lock);
 241         list_add_tail(&entry->list, &acpi_prt_list);
 242         spin_unlock(&acpi_prt_lock);
 243
 244         return 0;
 245 }
 246
 247 int acpi_pci_irq_add_prt(acpi_handle handle, struct pci_bus *bus)
 248 {
 249         acpi_status status;
 250         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 251         struct acpi_pci_routing_table *entry;
 252
 253         /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
 254         status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 255         if (ACPI_FAILURE(status))
 256                 return -ENODEV;
 257
 258         printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
 259                (char *) buffer.pointer);
 260
 261         kfree(buffer.pointer);
 262
 263         buffer.length = ACPI_ALLOCATE_BUFFER;
 264         buffer.pointer = NULL;
 265
 266         status = acpi_get_irq_routing_table(handle, &buffer);
 267         if (ACPI_FAILURE(status)) {
 268                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
 269                                 acpi_format_exception(status)));
 270                 kfree(buffer.pointer);
 271                 return -ENODEV;
 272         }
 273
 274         entry = buffer.pointer;
 275         while (entry && (entry->length > 0)) {
 276                 acpi_pci_irq_add_entry(handle, bus, entry);
 277                 entry = (struct acpi_pci_routing_table *)
 278                     ((unsigned long)entry + entry->length);
 279         }
 280
 281         kfree(buffer.pointer);
 282         return 0;
 283 }
 284
 285 void acpi_pci_irq_del_prt(struct pci_bus *bus)
 286 {
 287         struct acpi_prt_entry *entry, *tmp;
 288
 289         printk(KERN_DEBUG
 290                "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
 291                pci_domain_nr(bus), bus->number);
 292         spin_lock(&acpi_prt_lock);
 293         list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
 294                 if (pci_domain_nr(bus) == entry->id.segment
 295                         && bus->number == entry->id.bus) {
 296                         list_del(&entry->list);
 297                         kfree(entry);
 298                 }
 299         }
 300         spin_unlock(&acpi_prt_lock);
 301 }
 302
 303 /* --------------------------------------------------------------------------
 304                           PCI Interrupt Routing Support
 305    -------------------------------------------------------------------------- */
 306 #ifdef CONFIG_X86_IO_APIC
 307 extern int noioapicquirk;
 308 extern int noioapicreroute;
 309
 310 static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
 311 {
 312         struct pci_bus *bus_it;
 313
 314         for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
 315                 if (!bus_it->self)
 316                         return 0;
 317                 if (bus_it->self->irq_reroute_variant)
 318                         return bus_it->self->irq_reroute_variant;
 319         }
 320         return 0;
 321 }
 322
 323 /*
 324  * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
 325  * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
 326  * during interrupt handling). When this INTx generation cannot be disabled,
 327  * we reroute these interrupts to their legacy equivalent to get rid of
 328  * spurious interrupts.
 329  */
 330 static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
 331                                        struct acpi_prt_entry *entry)
 332 {
 333         if (noioapicquirk || noioapicreroute) {
 334                 return 0;
 335         } else {
 336                 switch (bridge_has_boot_interrupt_variant(dev->bus)) {
 337                 case 0:
 338                         /* no rerouting necessary */
 339                         return 0;
 340                 case INTEL_IRQ_REROUTE_VARIANT:
 341                         /*
 342                          * Remap according to INTx routing table in 6700PXH
 343                          * specs, intel order number 302628-002, section
 344                          * 2.15.2. Other chipsets (80332, ...) have the same
 345                          * mapping and are handled here as well.
 346                          */
 347                         dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
 348                                  "IRQ %d\n", entry->index,
 349                                  (entry->index % 4) + 16);
 350                         entry->index = (entry->index % 4) + 16;
 351                         return 1;
 352                 default:
 353                         dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
 354                                  "IRQ: unknown mapping\n", entry->index);
 355                         return -1;
 356                 }
 357         }
 358 }
 359 #endif /* CONFIG_X86_IO_APIC */
 360
 361 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 362 {
 363         struct acpi_prt_entry *entry;
 364         struct pci_dev *bridge;
 365         u8 bridge_pin, orig_pin = pin;
 366
 367         entry = acpi_pci_irq_find_prt_entry(dev, pin);
 368         if (entry) {
 369 #ifdef CONFIG_X86_IO_APIC
 370                 acpi_reroute_boot_interrupt(dev, entry);
 371 #endif /* CONFIG_X86_IO_APIC */
 372                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n",
 373                                   pci_name(dev), pin_name(pin)));
 374                 return entry;
 375         }
 376
 377         /*
 378          * Attempt to derive an IRQ for this device from a parent bridge's
 379          * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
 380          */
 381         bridge = dev->bus->self;
 382         while (bridge) {
 383                 pin = pci_swizzle_interrupt_pin(dev, pin);
 384
 385                 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
 386                         /* PC card has the same IRQ as its cardbridge */
 387                         bridge_pin = bridge->pin;
 388                         if (!bridge_pin) {
 389                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 390                                                   "No interrupt pin configured for device %s\n",
 391                                                   pci_name(bridge)));
 392                                 return NULL;
 393                         }
 394                         pin = bridge_pin;
 395                 }
 396
 397                 entry = acpi_pci_irq_find_prt_entry(bridge, pin);
 398                 if (entry) {
 399                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 400                                          "Derived GSI for %s INT %c from %s\n",
 401                                          pci_name(dev), pin_name(orig_pin),
 402                                          pci_name(bridge)));
 403                         return entry;
 404                 }
 405
 406                 dev = bridge;
 407                 bridge = dev->bus->self;
 408         }
 409
 410         dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
 411                  pin_name(orig_pin));
 412         return NULL;
 413 }
 414
 415 int acpi_pci_irq_enable(struct pci_dev *dev)
 416 {
 417         struct acpi_prt_entry *entry;
 418         int gsi;
 419         u8 pin;
 420         int triggering = ACPI_LEVEL_SENSITIVE;
 421         int polarity = ACPI_ACTIVE_LOW;
 422         char *link = NULL;
 423         char link_desc[16];
 424         int rc;
 425
 426         pin = dev->pin;
 427         if (!pin) {
 428                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 429                                   "No interrupt pin configured for device %s\n",
 430                                   pci_name(dev)));
 431                 return 0;
 432         }
 433
 434         entry = acpi_pci_irq_lookup(dev, pin);
 435         if (!entry) {
 436                 /*
 437                  * IDE legacy mode controller IRQs are magic. Why do compat
 438                  * extensions always make such a nasty mess.
 439                  */
 440                 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
 441                                 (dev->class & 0x05) == 0)
 442                         return 0;
 443         }
 444
 445         if (entry) {
 446                 if (entry->link)
 447                         gsi = acpi_pci_link_allocate_irq(entry->link,
 448                                                          entry->index,
 449                                                          &triggering, &polarity,
 450                                                          &link);
 451                 else
 452                         gsi = entry->index;
 453         } else
 454                 gsi = -1;
 455
 456         /*
 457          * No IRQ known to the ACPI subsystem - maybe the BIOS /
 458          * driver reported one, then use it. Exit in any case.
 459          */
 460         if (gsi < 0) {
 461                 u32 dev_gsi;
 462                 /* Interrupt Line values above 0xF are forbidden */
 463                 if (dev->irq > 0 && (dev->irq <= 0xF) &&
 464                     (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
 465                         dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",
 466                                  pin_name(pin), dev->irq);
 467                         acpi_register_gsi(&dev->dev, dev_gsi,
 468                                           ACPI_LEVEL_SENSITIVE,
 469                                           ACPI_ACTIVE_LOW);
 470                 } else {
 471                         dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
 472                                  pin_name(pin));
 473                 }
 474                 return 0;
 475         }
 476
 477         rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
 478         if (rc < 0) {
 479                 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
 480                          pin_name(pin));
 481                 return rc;
 482         }
 483         dev->irq = rc;
 484
 485         if (link)
 486                 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
 487         else
 488                 link_desc[0] = '\0';
 489
 490         dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
 491                 pin_name(pin), link_desc, gsi,
 492                 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
 493                 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
 494
 495         return 0;
 496 }
 497
 498 void acpi_pci_irq_disable(struct pci_dev *dev)
 499 {
 500         struct acpi_prt_entry *entry;
 501         int gsi;
 502         u8 pin;
 503
 504         pin = dev->pin;
 505         if (!pin)
 506                 return;
 507
 508         entry = acpi_pci_irq_lookup(dev, pin);
 509         if (!entry)
 510                 return;
 511
 512         if (entry->link)
 513                 gsi = acpi_pci_link_free_irq(entry->link);
 514         else
 515                 gsi = entry->index;
 516
 517         /*
 518          * TBD: It might be worth clearing dev->irq by magic constant
 519          * (e.g. PCI_UNDEFINED_IRQ).
 520          */
 521
 522         dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
 523         acpi_unregister_gsi(gsi);
 524 }