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