pci_link.c revision f084dbb939070281be7c882db63a4a428c51fcf4
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 49ACPI_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 56static int acpi_pci_link_add(struct acpi_device *device, 57 const struct acpi_device_id *not_used); 58static void acpi_pci_link_remove(struct acpi_device *device); 59 60static const struct acpi_device_id link_device_ids[] = { 61 {"PNP0C0F", 0}, 62 {"", 0}, 63}; 64 65static 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 */ 75struct 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 86struct 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 93static LIST_HEAD(acpi_link_list); 94static 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 */ 103static 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 173static 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 191static 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 */ 248static 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 296static 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 resource->end.length = sizeof(struct acpi_resource); 358 359 /* Attempt to set the resource */ 360 status = acpi_set_current_resources(link->device->handle, &buffer); 361 362 /* check for total failure */ 363 if (ACPI_FAILURE(status)) { 364 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS")); 365 result = -ENODEV; 366 goto end; 367 } 368 369 /* Query _STA, set device->status */ 370 result = acpi_bus_get_status(link->device); 371 if (result) { 372 printk(KERN_ERR PREFIX "Unable to read status\n"); 373 goto end; 374 } 375 if (!link->device->status.enabled) { 376 printk(KERN_WARNING PREFIX 377 "%s [%s] disabled and referenced, BIOS bug\n", 378 acpi_device_name(link->device), 379 acpi_device_bid(link->device)); 380 } 381 382 /* Query _CRS, set link->irq.active */ 383 result = acpi_pci_link_get_current(link); 384 if (result) { 385 goto end; 386 } 387 388 /* 389 * Is current setting not what we set? 390 * set link->irq.active 391 */ 392 if (link->irq.active != irq) { 393 /* 394 * policy: when _CRS doesn't return what we just _SRS 395 * assume _SRS worked and override _CRS value. 396 */ 397 printk(KERN_WARNING PREFIX 398 "%s [%s] BIOS reported IRQ %d, using IRQ %d\n", 399 acpi_device_name(link->device), 400 acpi_device_bid(link->device), link->irq.active, irq); 401 link->irq.active = irq; 402 } 403 404 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active)); 405 406 end: 407 kfree(resource); 408 return result; 409} 410 411/* -------------------------------------------------------------------------- 412 PCI Link IRQ Management 413 -------------------------------------------------------------------------- */ 414 415/* 416 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt 417 * Link Devices to move the PIRQs around to minimize sharing. 418 * 419 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs 420 * that the BIOS has already set to active. This is necessary because 421 * ACPI has no automatic means of knowing what ISA IRQs are used. Note that 422 * if the BIOS doesn't set a Link Device active, ACPI needs to program it 423 * even if acpi_irq_nobalance is set. 424 * 425 * A tables of penalties avoids directing PCI interrupts to well known 426 * ISA IRQs. Boot params are available to over-ride the default table: 427 * 428 * List interrupts that are free for PCI use. 429 * acpi_irq_pci=n[,m] 430 * 431 * List interrupts that should not be used for PCI: 432 * acpi_irq_isa=n[,m] 433 * 434 * Note that PCI IRQ routers have a list of possible IRQs, 435 * which may not include the IRQs this table says are available. 436 * 437 * Since this heuristic can't tell the difference between a link 438 * that no device will attach to, vs. a link which may be shared 439 * by multiple active devices -- it is not optimal. 440 * 441 * If interrupt performance is that important, get an IO-APIC system 442 * with a pin dedicated to each device. Or for that matter, an MSI 443 * enabled system. 444 */ 445 446#define ACPI_MAX_IRQS 256 447#define ACPI_MAX_ISA_IRQ 16 448 449#define PIRQ_PENALTY_PCI_AVAILABLE (0) 450#define PIRQ_PENALTY_PCI_POSSIBLE (16*16) 451#define PIRQ_PENALTY_PCI_USING (16*16*16) 452#define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16) 453#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16) 454#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16) 455 456static int acpi_irq_penalty[ACPI_MAX_IRQS] = { 457 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */ 458 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */ 459 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */ 460 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */ 461 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */ 462 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */ 463 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */ 464 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */ 465 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */ 466 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */ 467 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */ 468 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */ 469 PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */ 470 PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */ 471 PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */ 472 PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */ 473 /* >IRQ15 */ 474}; 475 476int __init acpi_irq_penalty_init(void) 477{ 478 struct acpi_pci_link *link; 479 int i; 480 481 /* 482 * Update penalties to facilitate IRQ balancing. 483 */ 484 list_for_each_entry(link, &acpi_link_list, list) { 485 486 /* 487 * reflect the possible and active irqs in the penalty table -- 488 * useful for breaking ties. 489 */ 490 if (link->irq.possible_count) { 491 int penalty = 492 PIRQ_PENALTY_PCI_POSSIBLE / 493 link->irq.possible_count; 494 495 for (i = 0; i < link->irq.possible_count; i++) { 496 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ) 497 acpi_irq_penalty[link->irq. 498 possible[i]] += 499 penalty; 500 } 501 502 } else if (link->irq.active) { 503 acpi_irq_penalty[link->irq.active] += 504 PIRQ_PENALTY_PCI_POSSIBLE; 505 } 506 } 507 /* Add a penalty for the SCI */ 508 acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING; 509 return 0; 510} 511 512static int acpi_irq_balance = -1; /* 0: static, 1: balance */ 513 514static int acpi_pci_link_allocate(struct acpi_pci_link *link) 515{ 516 int irq; 517 int i; 518 519 if (link->irq.initialized) { 520 if (link->refcnt == 0) 521 /* This means the link is disabled but initialized */ 522 acpi_pci_link_set(link, link->irq.active); 523 return 0; 524 } 525 526 /* 527 * search for active IRQ in list of possible IRQs. 528 */ 529 for (i = 0; i < link->irq.possible_count; ++i) { 530 if (link->irq.active == link->irq.possible[i]) 531 break; 532 } 533 /* 534 * forget active IRQ that is not in possible list 535 */ 536 if (i == link->irq.possible_count) { 537 if (acpi_strict) 538 printk(KERN_WARNING PREFIX "_CRS %d not found" 539 " in _PRS\n", link->irq.active); 540 link->irq.active = 0; 541 } 542 543 /* 544 * if active found, use it; else pick entry from end of possible list. 545 */ 546 if (link->irq.active) 547 irq = link->irq.active; 548 else 549 irq = link->irq.possible[link->irq.possible_count - 1]; 550 551 if (acpi_irq_balance || !link->irq.active) { 552 /* 553 * Select the best IRQ. This is done in reverse to promote 554 * the use of IRQs 9, 10, 11, and >15. 555 */ 556 for (i = (link->irq.possible_count - 1); i >= 0; i--) { 557 if (acpi_irq_penalty[irq] > 558 acpi_irq_penalty[link->irq.possible[i]]) 559 irq = link->irq.possible[i]; 560 } 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 */ 586int 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 */ 641int 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 692static 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 750static 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 758static 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 767static 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 */ 783static 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 */ 820void 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/* 831 * Over-ride default table to reserve additional IRQs for use by ISA 832 * e.g. acpi_irq_isa=5 833 * Useful for telling ACPI how not to interfere with your ISA sound card. 834 */ 835static int __init acpi_irq_isa(char *str) 836{ 837 return acpi_irq_penalty_update(str, 1); 838} 839 840__setup("acpi_irq_isa=", acpi_irq_isa); 841 842/* 843 * Over-ride default table to free additional IRQs for use by PCI 844 * e.g. acpi_irq_pci=7,15 845 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing. 846 */ 847static int __init acpi_irq_pci(char *str) 848{ 849 return acpi_irq_penalty_update(str, 0); 850} 851 852__setup("acpi_irq_pci=", acpi_irq_pci); 853 854static int __init acpi_irq_nobalance_set(char *str) 855{ 856 acpi_irq_balance = 0; 857 return 1; 858} 859 860__setup("acpi_irq_nobalance", acpi_irq_nobalance_set); 861 862static int __init acpi_irq_balance_set(char *str) 863{ 864 acpi_irq_balance = 1; 865 return 1; 866} 867 868__setup("acpi_irq_balance", acpi_irq_balance_set); 869 870static struct syscore_ops irqrouter_syscore_ops = { 871 .resume = irqrouter_resume, 872}; 873 874void __init acpi_pci_link_init(void) 875{ 876 if (acpi_noirq) 877 return; 878 879 if (acpi_irq_balance == -1) { 880 /* no command line switch: enable balancing in IOAPIC mode */ 881 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC) 882 acpi_irq_balance = 1; 883 else 884 acpi_irq_balance = 0; 885 } 886 register_syscore_ops(&irqrouter_syscore_ops); 887 acpi_scan_add_handler(&pci_link_handler); 888} 889