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