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