drivers/acpi/pci_link.c

   1 /*
   2  *  pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $)
   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  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  *
  26  * TBD:
  27  *      1. Support more than one IRQ resource entry per link device (index).
  28  *      2. Implement start/stop mechanism and use ACPI Bus Driver facilities
  29  *         for IRQ management (e.g. start()->_SRS).
  30  */
  31
  32 #include <linux/sysdev.h>
  33 #include <linux/kernel.h>
  34 #include <linux/module.h>
  35 #include <linux/init.h>
  36 #include <linux/types.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/spinlock.h>
  39 #include <linux/pm.h>
  40 #include <linux/pci.h>
  41 #include <linux/mutex.h>
  42
  43 #include <acpi/acpi_bus.h>
  44 #include <acpi/acpi_drivers.h>
  45
  46 #define _COMPONENT              ACPI_PCI_COMPONENT
  47 ACPI_MODULE_NAME("pci_link")
  48 #define ACPI_PCI_LINK_CLASS             "pci_irq_routing"
  49 #define ACPI_PCI_LINK_HID               "PNP0C0F"
  50 #define ACPI_PCI_LINK_DRIVER_NAME       "ACPI PCI Interrupt Link Driver"
  51 #define ACPI_PCI_LINK_DEVICE_NAME       "PCI Interrupt Link"
  52 #define ACPI_PCI_LINK_FILE_INFO         "info"
  53 #define ACPI_PCI_LINK_FILE_STATUS       "state"
  54 #define ACPI_PCI_LINK_MAX_POSSIBLE 16
  55 static int acpi_pci_link_add(struct acpi_device *device);
  56 static int acpi_pci_link_remove(struct acpi_device *device, int type);
  57
  58 static struct acpi_driver acpi_pci_link_driver = {
  59         .name = ACPI_PCI_LINK_DRIVER_NAME,
  60         .class = ACPI_PCI_LINK_CLASS,
  61         .ids = ACPI_PCI_LINK_HID,
  62         .ops = {
  63                 .add = acpi_pci_link_add,
  64                 .remove = acpi_pci_link_remove,
  65                 },
  66 };
  67
  68 /*
  69  * If a link is initialized, we never change its active and initialized
  70  * later even the link is disable. Instead, we just repick the active irq
  71  */
  72 struct acpi_pci_link_irq {
  73         u8 active;              /* Current IRQ */
  74         u8 triggering;          /* All IRQs */
  75         u8 polarity;    /* All IRQs */
  76         u8 resource_type;
  77         u8 possible_count;
  78         u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
  79         u8 initialized:1;
  80         u8 reserved:7;
  81 };
  82
  83 struct acpi_pci_link {
  84         struct list_head node;
  85         struct acpi_device *device;
  86         acpi_handle handle;
  87         struct acpi_pci_link_irq irq;
  88         int refcnt;
  89 };
  90
  91 static struct {
  92         int count;
  93         struct list_head entries;
  94 } acpi_link;
  95 DEFINE_MUTEX(acpi_link_lock);
  96
  97 /* --------------------------------------------------------------------------
  98                             PCI Link Device Management
  99    -------------------------------------------------------------------------- */
 100
 101 /*
 102  * set context (link) possible list from resource list
 103  */
 104 static acpi_status
 105 acpi_pci_link_check_possible(struct acpi_resource *resource, void *context)
 106 {
 107         struct acpi_pci_link *link = (struct acpi_pci_link *)context;
 108         u32 i = 0;
 109
 110         ACPI_FUNCTION_TRACE("acpi_pci_link_check_possible");
 111
 112         switch (resource->type) {
 113         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
 114                 return_ACPI_STATUS(AE_OK);
 115         case ACPI_RESOURCE_TYPE_IRQ:
 116                 {
 117                         struct acpi_resource_irq *p = &resource->data.irq;
 118                         if (!p || !p->interrupt_count) {
 119                                 printk(KERN_WARNING PREFIX "Blank IRQ resource\n");
 120                                 return_ACPI_STATUS(AE_OK);
 121                         }
 122                         for (i = 0;
 123                              (i < p->interrupt_count
 124                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
 125                                 if (!p->interrupts[i]) {
 126                                         printk(KERN_WARNING PREFIX "Invalid IRQ %d\n",
 127                                                       p->interrupts[i]);
 128                                         continue;
 129                                 }
 130                                 link->irq.possible[i] = p->interrupts[i];
 131                                 link->irq.possible_count++;
 132                         }
 133                         link->irq.triggering = p->triggering;
 134                         link->irq.polarity = p->polarity;
 135                         link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
 136                         break;
 137                 }
 138         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
 139                 {
 140                         struct acpi_resource_extended_irq *p =
 141                             &resource->data.extended_irq;
 142                         if (!p || !p->interrupt_count) {
 143                                 printk(KERN_WARNING PREFIX
 144                                               "Blank EXT IRQ resource\n");
 145                                 return_ACPI_STATUS(AE_OK);
 146                         }
 147                         for (i = 0;
 148                              (i < p->interrupt_count
 149                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
 150                                 if (!p->interrupts[i]) {
 151                                         printk(KERN_WARNING PREFIX "Invalid IRQ %d\n",
 152                                                       p->interrupts[i]);
 153                                         continue;
 154                                 }
 155                                 link->irq.possible[i] = p->interrupts[i];
 156                                 link->irq.possible_count++;
 157                         }
 158                         link->irq.triggering = p->triggering;
 159                         link->irq.polarity = p->polarity;
 160                         link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
 161                         break;
 162                 }
 163         default:
 164                 printk(KERN_ERR PREFIX "Resource is not an IRQ entry\n");
 165                 return_ACPI_STATUS(AE_OK);
 166         }
 167
 168         return_ACPI_STATUS(AE_CTRL_TERMINATE);
 169 }
 170
 171 static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
 172 {
 173         acpi_status status;
 174
 175         ACPI_FUNCTION_TRACE("acpi_pci_link_get_possible");
 176
 177         if (!link)
 178                 return_VALUE(-EINVAL);
 179
 180         status = acpi_walk_resources(link->handle, METHOD_NAME__PRS,
 181                                      acpi_pci_link_check_possible, link);
 182         if (ACPI_FAILURE(status)) {
 183                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
 184                 return_VALUE(-ENODEV);
 185         }
 186
 187         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 188                           "Found %d possible IRQs\n",
 189                           link->irq.possible_count));
 190
 191         return_VALUE(0);
 192 }
 193
 194 static acpi_status
 195 acpi_pci_link_check_current(struct acpi_resource *resource, void *context)
 196 {
 197         int *irq = (int *)context;
 198
 199         ACPI_FUNCTION_TRACE("acpi_pci_link_check_current");
 200
 201         switch (resource->type) {
 202         case ACPI_RESOURCE_TYPE_IRQ:
 203                 {
 204                         struct acpi_resource_irq *p = &resource->data.irq;
 205                         if (!p || !p->interrupt_count) {
 206                                 /*
 207                                  * IRQ descriptors may have no IRQ# bits set,
 208                                  * particularly those those w/ _STA disabled
 209                                  */
 210                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 211                                                   "Blank IRQ resource\n"));
 212                                 return_ACPI_STATUS(AE_OK);
 213                         }
 214                         *irq = p->interrupts[0];
 215                         break;
 216                 }
 217         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
 218                 {
 219                         struct acpi_resource_extended_irq *p =
 220                             &resource->data.extended_irq;
 221                         if (!p || !p->interrupt_count) {
 222                                 /*
 223                                  * extended IRQ descriptors must
 224                                  * return at least 1 IRQ
 225                                  */
 226                                 printk(KERN_WARNING PREFIX
 227                                               "Blank EXT IRQ resource\n");
 228                                 return_ACPI_STATUS(AE_OK);
 229                         }
 230                         *irq = p->interrupts[0];
 231                         break;
 232                 }
 233                 break;
 234         default:
 235                 printk(KERN_ERR PREFIX "Resource %d isn't an IRQ\n", resource->type);
 236         case ACPI_RESOURCE_TYPE_END_TAG:
 237                 return_ACPI_STATUS(AE_OK);
 238         }
 239         return_ACPI_STATUS(AE_CTRL_TERMINATE);
 240 }
 241
 242 /*
 243  * Run _CRS and set link->irq.active
 244  *
 245  * return value:
 246  * 0 - success
 247  * !0 - failure
 248  */
 249 static int acpi_pci_link_get_current(struct acpi_pci_link *link)
 250 {
 251         int result = 0;
 252         acpi_status status = AE_OK;
 253         int irq = 0;
 254
 255         ACPI_FUNCTION_TRACE("acpi_pci_link_get_current");
 256
 257         if (!link || !link->handle)
 258                 return_VALUE(-EINVAL);
 259
 260         link->irq.active = 0;
 261
 262         /* in practice, status disabled is meaningless, ignore it */
 263         if (acpi_strict) {
 264                 /* Query _STA, set link->device->status */
 265                 result = acpi_bus_get_status(link->device);
 266                 if (result) {
 267                         printk(KERN_ERR PREFIX "Unable to read status\n");
 268                         goto end;
 269                 }
 270
 271                 if (!link->device->status.enabled) {
 272                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
 273                         return_VALUE(0);
 274                 }
 275         }
 276
 277         /*
 278          * Query and parse _CRS to get the current IRQ assignment.
 279          */
 280
 281         status = acpi_walk_resources(link->handle, METHOD_NAME__CRS,
 282                                      acpi_pci_link_check_current, &irq);
 283         if (ACPI_FAILURE(status)) {
 284                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
 285                 result = -ENODEV;
 286                 goto end;
 287         }
 288
 289         if (acpi_strict && !irq) {
 290                 printk(KERN_ERR PREFIX "_CRS returned 0\n");
 291                 result = -ENODEV;
 292         }
 293
 294         link->irq.active = irq;
 295
 296         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
 297
 298       end:
 299         return_VALUE(result);
 300 }
 301
 302 static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
 303 {
 304         int result = 0;
 305         acpi_status status = AE_OK;
 306         struct {
 307                 struct acpi_resource res;
 308                 struct acpi_resource end;
 309         } *resource;
 310         struct acpi_buffer buffer = { 0, NULL };
 311
 312         ACPI_FUNCTION_TRACE("acpi_pci_link_set");
 313
 314         if (!link || !irq)
 315                 return_VALUE(-EINVAL);
 316
 317         resource = kmalloc(sizeof(*resource) + 1, GFP_ATOMIC);
 318         if (!resource)
 319                 return_VALUE(-ENOMEM);
 320
 321         memset(resource, 0, sizeof(*resource) + 1);
 322         buffer.length = sizeof(*resource) + 1;
 323         buffer.pointer = resource;
 324
 325         switch (link->irq.resource_type) {
 326         case ACPI_RESOURCE_TYPE_IRQ:
 327                 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
 328                 resource->res.length = sizeof(struct acpi_resource);
 329                 resource->res.data.irq.triggering = link->irq.triggering;
 330                 resource->res.data.irq.polarity =
 331                     link->irq.polarity;
 332                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
 333                         resource->res.data.irq.sharable =
 334                             ACPI_EXCLUSIVE;
 335                 else
 336                         resource->res.data.irq.sharable = ACPI_SHARED;
 337                 resource->res.data.irq.interrupt_count = 1;
 338                 resource->res.data.irq.interrupts[0] = irq;
 339                 break;
 340
 341         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
 342                 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
 343                 resource->res.length = sizeof(struct acpi_resource);
 344                 resource->res.data.extended_irq.producer_consumer =
 345                     ACPI_CONSUMER;
 346                 resource->res.data.extended_irq.triggering =
 347                     link->irq.triggering;
 348                 resource->res.data.extended_irq.polarity =
 349                     link->irq.polarity;
 350                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
 351                         resource->res.data.irq.sharable =
 352                             ACPI_EXCLUSIVE;
 353                 else
 354                         resource->res.data.irq.sharable = ACPI_SHARED;
 355                 resource->res.data.extended_irq.interrupt_count = 1;
 356                 resource->res.data.extended_irq.interrupts[0] = irq;
 357                 /* ignore resource_source, it's optional */
 358                 break;
 359         default:
 360                 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
 361                 result = -EINVAL;
 362                 goto end;
 363
 364         }
 365         resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
 366
 367         /* Attempt to set the resource */
 368         status = acpi_set_current_resources(link->handle, &buffer);
 369
 370         /* check for total failure */
 371         if (ACPI_FAILURE(status)) {
 372                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
 373                 result = -ENODEV;
 374                 goto end;
 375         }
 376
 377         /* Query _STA, set device->status */
 378         result = acpi_bus_get_status(link->device);
 379         if (result) {
 380                 printk(KERN_ERR PREFIX "Unable to read status\n");
 381                 goto end;
 382         }
 383         if (!link->device->status.enabled) {
 384                 printk(KERN_WARNING PREFIX
 385                               "%s [%s] disabled and referenced, BIOS bug\n",
 386                               acpi_device_name(link->device),
 387                               acpi_device_bid(link->device));
 388         }
 389
 390         /* Query _CRS, set link->irq.active */
 391         result = acpi_pci_link_get_current(link);
 392         if (result) {
 393                 goto end;
 394         }
 395
 396         /*
 397          * Is current setting not what we set?
 398          * set link->irq.active
 399          */
 400         if (link->irq.active != irq) {
 401                 /*
 402                  * policy: when _CRS doesn't return what we just _SRS
 403                  * assume _SRS worked and override _CRS value.
 404                  */
 405                 printk(KERN_WARNING PREFIX
 406                               "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
 407                               acpi_device_name(link->device),
 408                               acpi_device_bid(link->device), link->irq.active, irq);
 409                 link->irq.active = irq;
 410         }
 411
 412         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
 413
 414       end:
 415         kfree(resource);
 416         return_VALUE(result);
 417 }
 418
 419 /* --------------------------------------------------------------------------
 420                             PCI Link IRQ Management
 421    -------------------------------------------------------------------------- */
 422
 423 /*
 424  * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
 425  * Link Devices to move the PIRQs around to minimize sharing.
 426  *
 427  * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
 428  * that the BIOS has already set to active.  This is necessary because
 429  * ACPI has no automatic means of knowing what ISA IRQs are used.  Note that
 430  * if the BIOS doesn't set a Link Device active, ACPI needs to program it
 431  * even if acpi_irq_nobalance is set.
 432  *
 433  * A tables of penalties avoids directing PCI interrupts to well known
 434  * ISA IRQs. Boot params are available to over-ride the default table:
 435  *
 436  * List interrupts that are free for PCI use.
 437  * acpi_irq_pci=n[,m]
 438  *
 439  * List interrupts that should not be used for PCI:
 440  * acpi_irq_isa=n[,m]
 441  *
 442  * Note that PCI IRQ routers have a list of possible IRQs,
 443  * which may not include the IRQs this table says are available.
 444  *
 445  * Since this heuristic can't tell the difference between a link
 446  * that no device will attach to, vs. a link which may be shared
 447  * by multiple active devices -- it is not optimal.
 448  *
 449  * If interrupt performance is that important, get an IO-APIC system
 450  * with a pin dedicated to each device.  Or for that matter, an MSI
 451  * enabled system.
 452  */
 453
 454 #define ACPI_MAX_IRQS           256
 455 #define ACPI_MAX_ISA_IRQ        16
 456
 457 #define PIRQ_PENALTY_PCI_AVAILABLE      (0)
 458 #define PIRQ_PENALTY_PCI_POSSIBLE       (16*16)
 459 #define PIRQ_PENALTY_PCI_USING          (16*16*16)
 460 #define PIRQ_PENALTY_ISA_TYPICAL        (16*16*16*16)
 461 #define PIRQ_PENALTY_ISA_USED           (16*16*16*16*16)
 462 #define PIRQ_PENALTY_ISA_ALWAYS         (16*16*16*16*16*16)
 463
 464 static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
 465         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ0 timer */
 466         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ1 keyboard */
 467         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ2 cascade */
 468         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ3 serial */
 469         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ4 serial */
 470         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ5 sometimes SoundBlaster */
 471         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ6 */
 472         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ7 parallel, spurious */
 473         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ8 rtc, sometimes */
 474         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ9  PCI, often acpi */
 475         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ10 PCI */
 476         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ11 PCI */
 477         PIRQ_PENALTY_ISA_USED,  /* IRQ12 mouse */
 478         PIRQ_PENALTY_ISA_USED,  /* IRQ13 fpe, sometimes */
 479         PIRQ_PENALTY_ISA_USED,  /* IRQ14 ide0 */
 480         PIRQ_PENALTY_ISA_USED,  /* IRQ15 ide1 */
 481         /* >IRQ15 */
 482 };
 483
 484 int __init acpi_irq_penalty_init(void)
 485 {
 486         struct list_head *node = NULL;
 487         struct acpi_pci_link *link = NULL;
 488         int i = 0;
 489
 490         ACPI_FUNCTION_TRACE("acpi_irq_penalty_init");
 491
 492         /*
 493          * Update penalties to facilitate IRQ balancing.
 494          */
 495         list_for_each(node, &acpi_link.entries) {
 496
 497                 link = list_entry(node, struct acpi_pci_link, node);
 498                 if (!link) {
 499                         printk(KERN_ERR PREFIX "Invalid link context\n");
 500                         continue;
 501                 }
 502
 503                 /*
 504                  * reflect the possible and active irqs in the penalty table --
 505                  * useful for breaking ties.
 506                  */
 507                 if (link->irq.possible_count) {
 508                         int penalty =
 509                             PIRQ_PENALTY_PCI_POSSIBLE /
 510                             link->irq.possible_count;
 511
 512                         for (i = 0; i < link->irq.possible_count; i++) {
 513                                 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
 514                                         acpi_irq_penalty[link->irq.
 515                                                          possible[i]] +=
 516                                             penalty;
 517                         }
 518
 519                 } else if (link->irq.active) {
 520                         acpi_irq_penalty[link->irq.active] +=
 521                             PIRQ_PENALTY_PCI_POSSIBLE;
 522                 }
 523         }
 524         /* Add a penalty for the SCI */
 525         acpi_irq_penalty[acpi_fadt.sci_int] += PIRQ_PENALTY_PCI_USING;
 526
 527         return_VALUE(0);
 528 }
 529
 530 static int acpi_irq_balance;    /* 0: static, 1: balance */
 531
 532 static int acpi_pci_link_allocate(struct acpi_pci_link *link)
 533 {
 534         int irq;
 535         int i;
 536
 537         ACPI_FUNCTION_TRACE("acpi_pci_link_allocate");
 538
 539         if (link->irq.initialized) {
 540                 if (link->refcnt == 0)
 541                         /* This means the link is disabled but initialized */
 542                         acpi_pci_link_set(link, link->irq.active);
 543                 return_VALUE(0);
 544         }
 545
 546         /*
 547          * search for active IRQ in list of possible IRQs.
 548          */
 549         for (i = 0; i < link->irq.possible_count; ++i) {
 550                 if (link->irq.active == link->irq.possible[i])
 551                         break;
 552         }
 553         /*
 554          * forget active IRQ that is not in possible list
 555          */
 556         if (i == link->irq.possible_count) {
 557                 if (acpi_strict)
 558                         printk(KERN_WARNING PREFIX "_CRS %d not found"
 559                                       " in _PRS\n", link->irq.active);
 560                 link->irq.active = 0;
 561         }
 562
 563         /*
 564          * if active found, use it; else pick entry from end of possible list.
 565          */
 566         if (link->irq.active) {
 567                 irq = link->irq.active;
 568         } else {
 569                 irq = link->irq.possible[link->irq.possible_count - 1];
 570         }
 571
 572         if (acpi_irq_balance || !link->irq.active) {
 573                 /*
 574                  * Select the best IRQ.  This is done in reverse to promote
 575                  * the use of IRQs 9, 10, 11, and >15.
 576                  */
 577                 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
 578                         if (acpi_irq_penalty[irq] >
 579                             acpi_irq_penalty[link->irq.possible[i]])
 580                                 irq = link->irq.possible[i];
 581                 }
 582         }
 583
 584         /* Attempt to enable the link device at this IRQ. */
 585         if (acpi_pci_link_set(link, irq)) {
 586                 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
 587                             "Try pci=noacpi or acpi=off\n",
 588                             acpi_device_name(link->device),
 589                             acpi_device_bid(link->device));
 590                 return_VALUE(-ENODEV);
 591         } else {
 592                 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
 593                 printk(PREFIX "%s [%s] enabled at IRQ %d\n",
 594                        acpi_device_name(link->device),
 595                        acpi_device_bid(link->device), link->irq.active);
 596         }
 597
 598         link->irq.initialized = 1;
 599
 600         return_VALUE(0);
 601 }
 602
 603 /*
 604  * acpi_pci_link_allocate_irq
 605  * success: return IRQ >= 0
 606  * failure: return -1
 607  */
 608
 609 int
 610 acpi_pci_link_allocate_irq(acpi_handle handle,
 611                            int index,
 612                            int *triggering, int *polarity, char **name)
 613 {
 614         int result = 0;
 615         struct acpi_device *device = NULL;
 616         struct acpi_pci_link *link = NULL;
 617
 618         ACPI_FUNCTION_TRACE("acpi_pci_link_allocate_irq");
 619
 620         result = acpi_bus_get_device(handle, &device);
 621         if (result) {
 622                 printk(KERN_ERR PREFIX "Invalid link device\n");
 623                 return_VALUE(-1);
 624         }
 625
 626         link = (struct acpi_pci_link *)acpi_driver_data(device);
 627         if (!link) {
 628                 printk(KERN_ERR PREFIX "Invalid link context\n");
 629                 return_VALUE(-1);
 630         }
 631
 632         /* TBD: Support multiple index (IRQ) entries per Link Device */
 633         if (index) {
 634                 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
 635                 return_VALUE(-1);
 636         }
 637
 638         mutex_lock(&acpi_link_lock);
 639         if (acpi_pci_link_allocate(link)) {
 640                 mutex_unlock(&acpi_link_lock);
 641                 return_VALUE(-1);
 642         }
 643
 644         if (!link->irq.active) {
 645                 mutex_unlock(&acpi_link_lock);
 646                 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
 647                 return_VALUE(-1);
 648         }
 649         link->refcnt++;
 650         mutex_unlock(&acpi_link_lock);
 651
 652         if (triggering)
 653                 *triggering = link->irq.triggering;
 654         if (polarity)
 655                 *polarity = link->irq.polarity;
 656         if (name)
 657                 *name = acpi_device_bid(link->device);
 658         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 659                           "Link %s is referenced\n",
 660                           acpi_device_bid(link->device)));
 661         return_VALUE(link->irq.active);
 662 }
 663
 664 /*
 665  * We don't change link's irq information here.  After it is reenabled, we
 666  * continue use the info
 667  */
 668 int acpi_pci_link_free_irq(acpi_handle handle)
 669 {
 670         struct acpi_device *device = NULL;
 671         struct acpi_pci_link *link = NULL;
 672         acpi_status result;
 673
 674         ACPI_FUNCTION_TRACE("acpi_pci_link_free_irq");
 675
 676         result = acpi_bus_get_device(handle, &device);
 677         if (result) {
 678                 printk(KERN_ERR PREFIX "Invalid link device\n");
 679                 return_VALUE(-1);
 680         }
 681
 682         link = (struct acpi_pci_link *)acpi_driver_data(device);
 683         if (!link) {
 684                 printk(KERN_ERR PREFIX "Invalid link context\n");
 685                 return_VALUE(-1);
 686         }
 687
 688         mutex_lock(&acpi_link_lock);
 689         if (!link->irq.initialized) {
 690                 mutex_unlock(&acpi_link_lock);
 691                 printk(KERN_ERR PREFIX "Link isn't initialized\n");
 692                 return_VALUE(-1);
 693         }
 694 #ifdef  FUTURE_USE
 695         /*
 696          * The Link reference count allows us to _DISable an unused link
 697          * and suspend time, and set it again  on resume.
 698          * However, 2.6.12 still has irq_router.resume
 699          * which blindly restores the link state.
 700          * So we disable the reference count method
 701          * to prevent duplicate acpi_pci_link_set()
 702          * which would harm some systems
 703          */
 704         link->refcnt--;
 705 #endif
 706         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 707                           "Link %s is dereferenced\n",
 708                           acpi_device_bid(link->device)));
 709
 710         if (link->refcnt == 0) {
 711                 acpi_ut_evaluate_object(link->handle, "_DIS", 0, NULL);
 712         }
 713         mutex_unlock(&acpi_link_lock);
 714         return_VALUE(link->irq.active);
 715 }
 716
 717 /* --------------------------------------------------------------------------
 718                                  Driver Interface
 719    -------------------------------------------------------------------------- */
 720
 721 static int acpi_pci_link_add(struct acpi_device *device)
 722 {
 723         int result = 0;
 724         struct acpi_pci_link *link = NULL;
 725         int i = 0;
 726         int found = 0;
 727
 728         ACPI_FUNCTION_TRACE("acpi_pci_link_add");
 729
 730         if (!device)
 731                 return_VALUE(-EINVAL);
 732
 733         link = kmalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
 734         if (!link)
 735                 return_VALUE(-ENOMEM);
 736         memset(link, 0, sizeof(struct acpi_pci_link));
 737
 738         link->device = device;
 739         link->handle = device->handle;
 740         strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
 741         strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
 742         acpi_driver_data(device) = link;
 743
 744         mutex_lock(&acpi_link_lock);
 745         result = acpi_pci_link_get_possible(link);
 746         if (result)
 747                 goto end;
 748
 749         /* query and set link->irq.active */
 750         acpi_pci_link_get_current(link);
 751
 752         printk(PREFIX "%s [%s] (IRQs", acpi_device_name(device),
 753                acpi_device_bid(device));
 754         for (i = 0; i < link->irq.possible_count; i++) {
 755                 if (link->irq.active == link->irq.possible[i]) {
 756                         printk(" *%d", link->irq.possible[i]);
 757                         found = 1;
 758                 } else
 759                         printk(" %d", link->irq.possible[i]);
 760         }
 761
 762         printk(")");
 763
 764         if (!found)
 765                 printk(" *%d", link->irq.active);
 766
 767         if (!link->device->status.enabled)
 768                 printk(", disabled.");
 769
 770         printk("\n");
 771
 772         /* TBD: Acquire/release lock */
 773         list_add_tail(&link->node, &acpi_link.entries);
 774         acpi_link.count++;
 775
 776       end:
 777         /* disable all links -- to be activated on use */
 778         acpi_ut_evaluate_object(link->handle, "_DIS", 0, NULL);
 779         mutex_unlock(&acpi_link_lock);
 780
 781         if (result)
 782                 kfree(link);
 783
 784         return_VALUE(result);
 785 }
 786
 787 static int acpi_pci_link_resume(struct acpi_pci_link *link)
 788 {
 789         ACPI_FUNCTION_TRACE("acpi_pci_link_resume");
 790
 791         if (link->refcnt && link->irq.active && link->irq.initialized)
 792                 return_VALUE(acpi_pci_link_set(link, link->irq.active));
 793         else
 794                 return_VALUE(0);
 795 }
 796
 797 /*
 798  * FIXME: this is a workaround to avoid nasty warning.  It will be removed
 799  * after every device calls pci_disable_device in .resume.
 800  */
 801 int acpi_in_resume;
 802 static int irqrouter_resume(struct sys_device *dev)
 803 {
 804         struct list_head *node = NULL;
 805         struct acpi_pci_link *link = NULL;
 806
 807         ACPI_FUNCTION_TRACE("irqrouter_resume");
 808
 809         /* Make sure SCI is enabled again (Apple firmware bug?) */
 810         acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1, ACPI_MTX_DO_NOT_LOCK);
 811
 812         acpi_in_resume = 1;
 813         list_for_each(node, &acpi_link.entries) {
 814                 link = list_entry(node, struct acpi_pci_link, node);
 815                 if (!link) {
 816                         printk(KERN_ERR PREFIX "Invalid link context\n");
 817                         continue;
 818                 }
 819                 acpi_pci_link_resume(link);
 820         }
 821         acpi_in_resume = 0;
 822         return_VALUE(0);
 823 }
 824
 825 static int acpi_pci_link_remove(struct acpi_device *device, int type)
 826 {
 827         struct acpi_pci_link *link = NULL;
 828
 829         ACPI_FUNCTION_TRACE("acpi_pci_link_remove");
 830
 831         if (!device || !acpi_driver_data(device))
 832                 return_VALUE(-EINVAL);
 833
 834         link = (struct acpi_pci_link *)acpi_driver_data(device);
 835
 836         mutex_lock(&acpi_link_lock);
 837         list_del(&link->node);
 838         mutex_unlock(&acpi_link_lock);
 839
 840         kfree(link);
 841
 842         return_VALUE(0);
 843 }
 844
 845 /*
 846  * modify acpi_irq_penalty[] from cmdline
 847  */
 848 static int __init acpi_irq_penalty_update(char *str, int used)
 849 {
 850         int i;
 851
 852         for (i = 0; i < 16; i++) {
 853                 int retval;
 854                 int irq;
 855
 856                 retval = get_option(&str, &irq);
 857
 858                 if (!retval)
 859                         break;  /* no number found */
 860
 861                 if (irq < 0)
 862                         continue;
 863
 864                 if (irq >= ACPI_MAX_IRQS)
 865                         continue;
 866
 867                 if (used)
 868                         acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
 869                 else
 870                         acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
 871
 872                 if (retval != 2)        /* no next number */
 873                         break;
 874         }
 875         return 1;
 876 }
 877
 878 /*
 879  * We'd like PNP to call this routine for the
 880  * single ISA_USED value for each legacy device.
 881  * But instead it calls us with each POSSIBLE setting.
 882  * There is no ISA_POSSIBLE weight, so we simply use
 883  * the (small) PCI_USING penalty.
 884  */
 885 void acpi_penalize_isa_irq(int irq, int active)
 886 {
 887         if (active)
 888                 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
 889         else
 890                 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
 891 }
 892
 893 /*
 894  * Over-ride default table to reserve additional IRQs for use by ISA
 895  * e.g. acpi_irq_isa=5
 896  * Useful for telling ACPI how not to interfere with your ISA sound card.
 897  */
 898 static int __init acpi_irq_isa(char *str)
 899 {
 900         return acpi_irq_penalty_update(str, 1);
 901 }
 902
 903 __setup("acpi_irq_isa=", acpi_irq_isa);
 904
 905 /*
 906  * Over-ride default table to free additional IRQs for use by PCI
 907  * e.g. acpi_irq_pci=7,15
 908  * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
 909  */
 910 static int __init acpi_irq_pci(char *str)
 911 {
 912         return acpi_irq_penalty_update(str, 0);
 913 }
 914
 915 __setup("acpi_irq_pci=", acpi_irq_pci);
 916
 917 static int __init acpi_irq_nobalance_set(char *str)
 918 {
 919         acpi_irq_balance = 0;
 920         return 1;
 921 }
 922
 923 __setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
 924
 925 int __init acpi_irq_balance_set(char *str)
 926 {
 927         acpi_irq_balance = 1;
 928         return 1;
 929 }
 930
 931 __setup("acpi_irq_balance", acpi_irq_balance_set);
 932
 933 /* FIXME: we will remove this interface after all drivers call pci_disable_device */
 934 static struct sysdev_class irqrouter_sysdev_class = {
 935         set_kset_name("irqrouter"),
 936         .resume = irqrouter_resume,
 937 };
 938
 939 static struct sys_device device_irqrouter = {
 940         .id = 0,
 941         .cls = &irqrouter_sysdev_class,
 942 };
 943
 944 static int __init irqrouter_init_sysfs(void)
 945 {
 946         int error;
 947
 948         ACPI_FUNCTION_TRACE("irqrouter_init_sysfs");
 949
 950         if (acpi_disabled || acpi_noirq)
 951                 return_VALUE(0);
 952
 953         error = sysdev_class_register(&irqrouter_sysdev_class);
 954         if (!error)
 955                 error = sysdev_register(&device_irqrouter);
 956
 957         return_VALUE(error);
 958 }
 959
 960 device_initcall(irqrouter_init_sysfs);
 961
 962 static int __init acpi_pci_link_init(void)
 963 {
 964         ACPI_FUNCTION_TRACE("acpi_pci_link_init");
 965
 966         if (acpi_noirq)
 967                 return_VALUE(0);
 968
 969         acpi_link.count = 0;
 970         INIT_LIST_HEAD(&acpi_link.entries);
 971
 972         if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
 973                 return_VALUE(-ENODEV);
 974
 975         return_VALUE(0);
 976 }
 977
 978 subsys_initcall(acpi_pci_link_init);