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