LXR linux-old/drivers/acpi/pci

   1/*
   2 *  pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 35 $)
   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/kernel.h>
  33#include <linux/module.h>
  34#include <linux/init.h>
  35#include <linux/types.h>
  36#include <linux/proc_fs.h>
  37#include <linux/spinlock.h>
  38#include <linux/pm.h>
  39#include <linux/pci.h>
  40
  41#include <acpi/acpi_bus.h>
  42#include <acpi/acpi_drivers.h>
  43
  44
  45#define _COMPONENT              ACPI_PCI_COMPONENT
  46ACPI_MODULE_NAME                ("pci_link")
  47
  48#define PREFIX                  "ACPI: "
  49
  50
  51#define ACPI_PCI_LINK_MAX_POSSIBLE 16
  52
  53static int acpi_pci_link_add (struct acpi_device *device);
  54static int acpi_pci_link_remove (struct acpi_device *device, int type);
  55
  56static struct acpi_driver acpi_pci_link_driver = {
  57        .name =         ACPI_PCI_LINK_DRIVER_NAME,
  58        .class =        ACPI_PCI_LINK_CLASS,
  59        .ids =          ACPI_PCI_LINK_HID,
  60        .ops =          {
  61                                .add =    acpi_pci_link_add,
  62                                .remove = acpi_pci_link_remove,
  63                        },
  64};
  65
  66struct acpi_pci_link_irq {
  67        u8                      active;                 /* Current IRQ */
  68        u8                      edge_level;             /* All IRQs */
  69        u8                      active_high_low;        /* All IRQs */
  70        u8                      setonboot;
  71        u8                      resource_type;
  72        u8                      possible_count;
  73        u8                      possible[ACPI_PCI_LINK_MAX_POSSIBLE];
  74};
  75
  76struct acpi_pci_link {
  77        struct list_head        node;
  78        struct acpi_device      *device;
  79        acpi_handle             handle;
  80        struct acpi_pci_link_irq irq;
  81};
  82
  83static struct {
  84        int                     count;
  85        struct list_head        entries;
  86}                               acpi_link;
  87
  88
  89/* --------------------------------------------------------------------------
  90                            PCI Link Device Management
  91   -------------------------------------------------------------------------- */
  92
  93/*
  94 * set context (link) possible list from resource list
  95 */
  96static acpi_status
  97acpi_pci_link_check_possible (
  98        struct acpi_resource    *resource,
  99        void                    *context)
 100{
 101        struct acpi_pci_link    *link = (struct acpi_pci_link *) context;
 102        u32                     i = 0;
 103
 104        ACPI_FUNCTION_TRACE("acpi_pci_link_check_possible");
 105
 106        switch (resource->id) {
 107        case ACPI_RSTYPE_START_DPF:
 108                return AE_OK;
 109        case ACPI_RSTYPE_IRQ:
 110        {
 111                struct acpi_resource_irq *p = &resource->data.irq;
 112                if (!p || !p->number_of_interrupts) {
 113                        ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Blank IRQ resource\n"));
 114                        return AE_OK;
 115                }
 116                for (i = 0; (i<p->number_of_interrupts && i<ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
 117                        if (!p->interrupts[i]) {
 118                                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ %d\n", p->interrupts[i]));
 119                                continue;
 120                        }
 121                        link->irq.possible[i] = p->interrupts[i];
 122                        link->irq.possible_count++;
 123                }
 124                link->irq.edge_level = p->edge_level;
 125                link->irq.active_high_low = p->active_high_low;
 126                link->irq.resource_type = ACPI_RSTYPE_IRQ;
 127                break;
 128        }
 129        case ACPI_RSTYPE_EXT_IRQ:
 130        {
 131                struct acpi_resource_ext_irq *p = &resource->data.extended_irq;
 132                if (!p || !p->number_of_interrupts) {
 133                        ACPI_DEBUG_PRINT((ACPI_DB_WARN, 
 134                                "Blank EXT IRQ resource\n"));
 135                        return AE_OK;
 136                }
 137                for (i = 0; (i<p->number_of_interrupts && i<ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
 138                        if (!p->interrupts[i]) {
 139                                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ %d\n", p->interrupts[i]));
 140                                continue;
 141                        }
 142                        link->irq.possible[i] = p->interrupts[i];
 143                        link->irq.possible_count++;
 144                }
 145                link->irq.edge_level = p->edge_level;
 146                link->irq.active_high_low = p->active_high_low;
 147                link->irq.resource_type = ACPI_RSTYPE_EXT_IRQ;
 148                break;
 149        }
 150        default:
 151                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, 
 152                        "Resource is not an IRQ entry\n"));
 153                return AE_OK;
 154        }
 155
 156        return AE_CTRL_TERMINATE;
 157}
 158
 159
 160static int
 161acpi_pci_link_get_possible (
 162        struct acpi_pci_link    *link)
 163{
 164        acpi_status             status;
 165
 166        ACPI_FUNCTION_TRACE("acpi_pci_link_get_possible");
 167
 168        if (!link)
 169                return_VALUE(-EINVAL);
 170
 171        status = acpi_walk_resources(link->handle, METHOD_NAME__PRS,
 172                        acpi_pci_link_check_possible, link);
 173        if (ACPI_FAILURE(status)) {
 174                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRS\n"));
 175                return_VALUE(-ENODEV);
 176        }
 177
 178        ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
 179                "Found %d possible IRQs\n", link->irq.possible_count));
 180
 181        return_VALUE(0);
 182}
 183
 184
 185static acpi_status
 186acpi_pci_link_check_current (
 187        struct acpi_resource    *resource,
 188        void                    *context)
 189{
 190        int                     *irq = (int *) context;
 191
 192        ACPI_FUNCTION_TRACE("acpi_pci_link_check_current");
 193
 194        switch (resource->id) {
 195        case ACPI_RSTYPE_IRQ:
 196        {
 197                struct acpi_resource_irq *p = &resource->data.irq;
 198                if (!p || !p->number_of_interrupts) {
 199                        /*
 200                         * IRQ descriptors may have no IRQ# bits set,
 201                         * particularly those those w/ _STA disabled
 202                         */
 203                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 204                                "Blank IRQ resource\n")); 
 205                        return AE_OK;
 206                }
 207                *irq = p->interrupts[0];
 208                break;
 209        }
 210        case ACPI_RSTYPE_EXT_IRQ:
 211        {
 212                struct acpi_resource_ext_irq *p = &resource->data.extended_irq;
 213                if (!p || !p->number_of_interrupts) {
 214                        /*
 215                         * extended IRQ descriptors must
 216                         * return at least 1 IRQ
 217                         */
 218                        ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 219                                "Blank EXT IRQ resource\n"));
 220                        return AE_OK;
 221                }
 222                *irq = p->interrupts[0];
 223                break;
 224        }
 225        default:
 226                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 227                        "Resource isn't an IRQ\n"));
 228                return AE_OK;
 229        }
 230        return AE_CTRL_TERMINATE;
 231}
 232
 233/*
 234 * Run _CRS and set link->irq.active
 235 *
 236 * return value:
 237 * 0 - success
 238 * !0 - failure
 239 */
 240static int
 241acpi_pci_link_get_current (
 242        struct acpi_pci_link    *link)
 243{
 244        int                     result = 0;
 245        acpi_status             status = AE_OK;
 246        int                     irq = 0;
 247
 248        ACPI_FUNCTION_TRACE("acpi_pci_link_get_current");
 249
 250        if (!link || !link->handle)
 251                return_VALUE(-EINVAL);
 252
 253        link->irq.active = 0;
 254
 255        /* in practice, status disabled is meaningless, ignore it */
 256        if (acpi_strict) {
 257                /* Query _STA, set link->device->status */
 258                result = acpi_bus_get_status(link->device);
 259                if (result) {
 260                        ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unable to read status\n"));
 261                        goto end;
 262                }
 263
 264                if (!link->device->status.enabled) {
 265                        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
 266                        return_VALUE(0);
 267                }
 268        }
 269
 270        /* 
 271         * Query and parse _CRS to get the current IRQ assignment. 
 272         */
 273
 274        status = acpi_walk_resources(link->handle, METHOD_NAME__CRS,
 275                        acpi_pci_link_check_current, &irq);
 276        if (ACPI_FAILURE(status)) {
 277                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _CRS\n"));
 278                result = -ENODEV;
 279                goto end;
 280        }
 281
 282        if (acpi_strict && !irq) {
 283                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "_CRS returned 0\n"));
 284                result = -ENODEV;
 285        }
 286
 287        link->irq.active = irq;
 288
 289        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
 290
 291end:
 292        return_VALUE(result);
 293}
 294
 295static int
 296acpi_pci_link_set (
 297        struct acpi_pci_link    *link,
 298        int                     irq)
 299{
 300        int                     result = 0;
 301        acpi_status             status = AE_OK;
 302        struct {
 303                struct acpi_resource    res;
 304                struct acpi_resource    end;
 305        }                       resource;
 306        struct acpi_buffer      buffer = {sizeof(resource)+1, &resource};
 307
 308        ACPI_FUNCTION_TRACE("acpi_pci_link_set");
 309
 310        if (!link || !irq)
 311                return_VALUE(-EINVAL);
 312
 313        memset(&resource, 0, sizeof(resource));
 314
 315        switch(link->irq.resource_type) {
 316        case ACPI_RSTYPE_IRQ:
 317                resource.res.id = ACPI_RSTYPE_IRQ;
 318                resource.res.length = sizeof(struct acpi_resource);
 319                resource.res.data.irq.edge_level = link->irq.edge_level;
 320                resource.res.data.irq.active_high_low = link->irq.active_high_low;
 321                if (link->irq.edge_level == ACPI_EDGE_SENSITIVE)
 322                        resource.res.data.irq.shared_exclusive = ACPI_EXCLUSIVE;
 323                else
 324                        resource.res.data.irq.shared_exclusive = ACPI_SHARED;
 325                resource.res.data.irq.number_of_interrupts = 1;
 326                resource.res.data.irq.interrupts[0] = irq;
 327                break;
 328           
 329        case ACPI_RSTYPE_EXT_IRQ:
 330                resource.res.id = ACPI_RSTYPE_EXT_IRQ;
 331                resource.res.length = sizeof(struct acpi_resource);
 332                resource.res.data.extended_irq.producer_consumer = ACPI_CONSUMER;
 333                resource.res.data.extended_irq.edge_level = link->irq.edge_level;
 334                resource.res.data.extended_irq.active_high_low = link->irq.active_high_low;
 335                if (link->irq.edge_level == ACPI_EDGE_SENSITIVE)
 336                        resource.res.data.irq.shared_exclusive = ACPI_EXCLUSIVE;
 337                else
 338                        resource.res.data.irq.shared_exclusive = ACPI_SHARED;
 339                resource.res.data.extended_irq.number_of_interrupts = 1;
 340                resource.res.data.extended_irq.interrupts[0] = irq;
 341                /* ignore resource_source, it's optional */
 342                break;
 343        default:
 344                printk("ACPI BUG: resource_type %d\n", link->irq.resource_type);
 345                return_VALUE(-EINVAL);
 346        }
 347        resource.end.id = ACPI_RSTYPE_END_TAG;
 348
 349        /* Attempt to set the resource */
 350        status = acpi_set_current_resources(link->handle, &buffer);
 351
 352        /* check for total failure */
 353        if (ACPI_FAILURE(status)) {
 354                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _SRS\n"));
 355                return_VALUE(-ENODEV);
 356        }
 357
 358        /* Query _STA, set device->status */
 359        result = acpi_bus_get_status(link->device);
 360        if (result) {
 361                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unable to read status\n"));
 362                return_VALUE(result);
 363        }
 364        if (!link->device->status.enabled) {
 365                printk(KERN_WARNING PREFIX
 366                        "%s [%s] disabled and referenced, BIOS bug.\n",
 367                        acpi_device_name(link->device),
 368                        acpi_device_bid(link->device));
 369        }
 370
 371        /* Query _CRS, set link->irq.active */
 372        result = acpi_pci_link_get_current(link);
 373        if (result) {
 374                return_VALUE(result);
 375        }
 376
 377        /*
 378         * Is current setting not what we set?
 379         * set link->irq.active
 380         */
 381        if (link->irq.active != irq) {
 382                /*
 383                 * policy: when _CRS doesn't return what we just _SRS
 384                 * assume _SRS worked and override _CRS value.
 385                 */
 386                printk(KERN_WARNING PREFIX
 387                        "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
 388                        acpi_device_name(link->device),
 389                        acpi_device_bid(link->device),
 390                        link->irq.active, irq);
 391                link->irq.active = irq;
 392        }
 393
 394        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
 395        
 396        return_VALUE(0);
 397}
 398
 399
 400/* --------------------------------------------------------------------------
 401                            PCI Link IRQ Management
 402   -------------------------------------------------------------------------- */
 403
 404/*
 405 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
 406 * Link Devices to move the PIRQs around to minimize sharing.
 407 * 
 408 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
 409 * that the BIOS has already set to active.  This is necessary because
 410 * ACPI has no automatic means of knowing what ISA IRQs are used.  Note that
 411 * if the BIOS doesn't set a Link Device active, ACPI needs to program it
 412 * even if acpi_irq_nobalance is set.
 413 *
 414 * A tables of penalties avoids directing PCI interrupts to well known
 415 * ISA IRQs. Boot params are available to over-ride the default table:
 416 *
 417 * List interrupts that are free for PCI use.
 418 * acpi_irq_pci=n[,m]
 419 *
 420 * List interrupts that should not be used for PCI:
 421 * acpi_irq_isa=n[,m]
 422 *
 423 * Note that PCI IRQ routers have a list of possible IRQs,
 424 * which may not include the IRQs this table says are available.
 425 * 
 426 * Since this heuristic can't tell the difference between a link
 427 * that no device will attach to, vs. a link which may be shared
 428 * by multiple active devices -- it is not optimal.
 429 *
 430 * If interrupt performance is that important, get an IO-APIC system
 431 * with a pin dedicated to each device.  Or for that matter, an MSI
 432 * enabled system.
 433 */
 434
 435#define ACPI_MAX_IRQS           256
 436#define ACPI_MAX_ISA_IRQ        16
 437
 438#define PIRQ_PENALTY_PCI_AVAILABLE      (0)
 439#define PIRQ_PENALTY_PCI_POSSIBLE       (16*16)
 440#define PIRQ_PENALTY_PCI_USING          (16*16*16)
 441#define PIRQ_PENALTY_ISA_TYPICAL        (16*16*16*16)
 442#define PIRQ_PENALTY_ISA_USED           (16*16*16*16*16)
 443#define PIRQ_PENALTY_ISA_ALWAYS         (16*16*16*16*16*16)
 444
 445static int __initdata acpi_irq_penalty[ACPI_MAX_IRQS] = {
 446        PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ0 timer */
 447        PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ1 keyboard */
 448        PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ2 cascade */
 449        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ3 serial */
 450        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ4 serial */
 451        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ5 sometimes SoundBlaster */
 452        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ6 */
 453        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ7 parallel, spurious */
 454        PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ8 rtc, sometimes */
 455        PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ9  PCI, often acpi */
 456        PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ10 PCI */
 457        PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ11 PCI */
 458        PIRQ_PENALTY_ISA_USED,  /* IRQ12 mouse */
 459        PIRQ_PENALTY_ISA_USED,  /* IRQ13 fpe, sometimes */
 460        PIRQ_PENALTY_ISA_USED,  /* IRQ14 ide0 */
 461        PIRQ_PENALTY_ISA_USED,  /* IRQ15 ide1 */
 462                        /* >IRQ15 */
 463};
 464
 465int
 466acpi_pci_link_check (void)
 467{
 468        struct list_head        *node = NULL;
 469        struct acpi_pci_link    *link = NULL;
 470        int                     i = 0;
 471
 472        ACPI_FUNCTION_TRACE("acpi_pci_link_check");
 473
 474        /*
 475         * Update penalties to facilitate IRQ balancing.
 476         */
 477        list_for_each(node, &acpi_link.entries) {
 478
 479                link = list_entry(node, struct acpi_pci_link, node);
 480                if (!link) {
 481                        ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid link context\n"));
 482                        continue;
 483                }
 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 = PIRQ_PENALTY_PCI_POSSIBLE / link->irq.possible_count;
 491
 492                        for (i = 0; i < link->irq.possible_count; i++) {
 493                                if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
 494                                        acpi_irq_penalty[link->irq.possible[i]] += penalty;
 495                        }
 496
 497                } else if (link->irq.active) {
 498                        acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_POSSIBLE;
 499                }
 500        }
 501        /* Add a penalty for the SCI */
 502        acpi_irq_penalty[acpi_fadt.sci_int] += PIRQ_PENALTY_PCI_USING;
 503
 504        return_VALUE(0);
 505}
 506
 507static int acpi_irq_balance;    /* 0: static, 1: balance */
 508
 509static int acpi_pci_link_allocate(struct acpi_pci_link* link) {
 510        int irq;
 511        int i;
 512
 513        ACPI_FUNCTION_TRACE("acpi_pci_link_allocate");
 514
 515        if (link->irq.setonboot)
 516                return_VALUE(0);
 517
 518        /*
 519         * search for active IRQ in list of possible IRQs.
 520         */
 521        for (i = 0; i < link->irq.possible_count; ++i) {
 522                if (link->irq.active == link->irq.possible[i])
 523                        break;
 524        }
 525        /*
 526         * forget active IRQ that is not in possible list
 527         */
 528        if (i == link->irq.possible_count) {
 529                if (acpi_strict)
 530                        printk(KERN_WARNING PREFIX "_CRS %d not found"
 531                                " in _PRS\n", link->irq.active);
 532                link->irq.active = 0;
 533        }
 534
 535        /*
 536         * if active found, use it; else pick entry from end of possible list.
 537         */
 538        if (link->irq.active) {
 539                irq = link->irq.active;
 540        } else {
 541                irq = link->irq.possible[link->irq.possible_count - 1];
 542        }
 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] > acpi_irq_penalty[link->irq.possible[i]])
 551                                irq = link->irq.possible[i];
 552                }
 553        }
 554
 555        /* Attempt to enable the link device at this IRQ. */
 556        if (acpi_pci_link_set(link, irq)) {
 557                printk(PREFIX "Unable to set IRQ for %s [%s] (likely buggy ACPI BIOS).\n"
 558                                "Try pci=noacpi or acpi=off\n",
 559                        acpi_device_name(link->device),
 560                        acpi_device_bid(link->device));
 561                return_VALUE(-ENODEV);
 562        } else {
 563                acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
 564                printk(PREFIX "%s [%s] enabled at IRQ %d\n", 
 565                        acpi_device_name(link->device),
 566                        acpi_device_bid(link->device), link->irq.active);
 567        }
 568
 569        link->irq.setonboot = 1;
 570
 571        return_VALUE(0);
 572}
 573
 574
 575int
 576acpi_pci_link_get_irq (
 577        acpi_handle             handle,
 578        int                     index,
 579        int*                    edge_level,
 580        int*                    active_high_low)
 581{
 582        int                     result = 0;
 583        struct acpi_device      *device = NULL;
 584        struct acpi_pci_link    *link = NULL;
 585
 586        ACPI_FUNCTION_TRACE("acpi_pci_link_get_irq");
 587
 588        result = acpi_bus_get_device(handle, &device);
 589        if (result) {
 590                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid link device\n"));
 591                return_VALUE(0);
 592        }
 593
 594        link = (struct acpi_pci_link *) acpi_driver_data(device);
 595        if (!link) {
 596                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid link context\n"));
 597                return_VALUE(0);
 598        }
 599
 600        /* TBD: Support multiple index (IRQ) entries per Link Device */
 601        if (index) {
 602                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid index %d\n", index));
 603                return_VALUE(0);
 604        }
 605
 606        if (acpi_pci_link_allocate(link))
 607                return_VALUE(0);
 608
 609        if (!link->irq.active) {
 610                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Link active IRQ is 0!\n"));
 611                return_VALUE(0);
 612        }
 613
 614        if (edge_level) *edge_level = link->irq.edge_level;
 615        if (active_high_low) *active_high_low = link->irq.active_high_low;
 616        return_VALUE(link->irq.active);
 617}
 618
 619
 620/* --------------------------------------------------------------------------
 621                                 Driver Interface
 622   -------------------------------------------------------------------------- */
 623
 624static int
 625acpi_pci_link_add (
 626        struct acpi_device *device)
 627{
 628        int                     result = 0;
 629        struct acpi_pci_link    *link = NULL;
 630        int                     i = 0;
 631        int                     found = 0;
 632
 633        ACPI_FUNCTION_TRACE("acpi_pci_link_add");
 634
 635        if (!device)
 636                return_VALUE(-EINVAL);
 637
 638        link = kmalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
 639        if (!link)
 640                return_VALUE(-ENOMEM);
 641        memset(link, 0, sizeof(struct acpi_pci_link));
 642
 643        link->device = device;
 644        link->handle = device->handle;
 645        sprintf(acpi_device_name(device), "%s", ACPI_PCI_LINK_DEVICE_NAME);
 646        sprintf(acpi_device_class(device), "%s", ACPI_PCI_LINK_CLASS);
 647        acpi_driver_data(device) = link;
 648
 649        result = acpi_pci_link_get_possible(link);
 650        if (result)
 651                goto end;
 652
 653        /* query and set link->irq.active */
 654        acpi_pci_link_get_current(link);
 655
 656        printk(PREFIX "%s [%s] (IRQs", acpi_device_name(device),
 657                acpi_device_bid(device));
 658        for (i = 0; i < link->irq.possible_count; i++) {
 659                if (link->irq.active == link->irq.possible[i]) {
 660                        printk(" *%d", link->irq.possible[i]);
 661                        found = 1;
 662                }
 663                else
 664                        printk(" %d", link->irq.possible[i]);
 665        }
 666
 667        printk(")");
 668
 669        if (!found)
 670                printk(" *%d", link->irq.active);
 671
 672        if(!link->device->status.enabled)
 673                printk(", disabled.");
 674
 675        printk("\n");
 676
 677        /* TBD: Acquire/release lock */
 678        list_add_tail(&link->node, &acpi_link.entries);
 679        acpi_link.count++;
 680
 681end:
 682        /* disable all links -- to be activated on use */
 683        acpi_ut_evaluate_object(link->handle, "_DIS", 0, NULL);
 684
 685        if (result)
 686                kfree(link);
 687
 688        return_VALUE(result);
 689}
 690
 691
 692static int
 693acpi_pci_link_remove (
 694        struct acpi_device      *device,
 695        int                     type)
 696{
 697        struct acpi_pci_link *link = NULL;
 698
 699        ACPI_FUNCTION_TRACE("acpi_pci_link_remove");
 700
 701        if (!device || !acpi_driver_data(device))
 702                return_VALUE(-EINVAL);
 703
 704        link = (struct acpi_pci_link *) acpi_driver_data(device);
 705
 706        /* TBD: Acquire/release lock */
 707        list_del(&link->node);
 708
 709        kfree(link);
 710
 711        return_VALUE(0);
 712}
 713
 714/*
 715 * modify acpi_irq_penalty[] from cmdline
 716 */
 717static int __init acpi_irq_penalty_update(char *str, int used)
 718{
 719        int i;
 720
 721        for (i = 0; i < 16; i++) {
 722                int retval;
 723                int irq;
 724
 725                retval = get_option(&str,&irq);
 726
 727                if (!retval)
 728                        break;  /* no number found */
 729
 730                if (irq < 0)
 731                        continue;
 732                
 733                if (irq >= ACPI_MAX_IRQS)
 734                        continue;
 735
 736                if (used)
 737                        acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
 738                else
 739                        acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
 740
 741                if (retval != 2)        /* no next number */
 742                        break;
 743        }
 744        return 1;
 745}
 746
 747/*
 748 * Over-ride default table to reserve additional IRQs for use by ISA
 749 * e.g. acpi_irq_isa=5
 750 * Useful for telling ACPI how not to interfere with your ISA sound card.
 751 */
 752static int __init acpi_irq_isa(char *str)
 753{
 754        return(acpi_irq_penalty_update(str, 1));
 755}
 756__setup("acpi_irq_isa=", acpi_irq_isa);
 757
 758/*
 759 * Over-ride default table to free additional IRQs for use by PCI
 760 * e.g. acpi_irq_pci=7,15
 761 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
 762 */
 763static int __init acpi_irq_pci(char *str)
 764{
 765        return(acpi_irq_penalty_update(str, 0));
 766}
 767__setup("acpi_irq_pci=", acpi_irq_pci);
 768
 769static int __init acpi_irq_nobalance_set(char *str)
 770{
 771        acpi_irq_balance = 0;
 772        return(1);
 773}
 774__setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
 775
 776int __init acpi_irq_balance_set(char *str)
 777{
 778        acpi_irq_balance = 1;
 779        return(1);
 780}
 781__setup("acpi_irq_balance", acpi_irq_balance_set);
 782
 783
 784int __init
 785acpi_pci_link_init (void)
 786{
 787        ACPI_FUNCTION_TRACE("acpi_pci_link_init");
 788
 789        acpi_link.count = 0;
 790        INIT_LIST_HEAD(&acpi_link.entries);
 791
 792        if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
 793                return_VALUE(-ENODEV);
 794
 795        return_VALUE(0);
 796}
 797