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