drivers/pci/msi.c

   1 /*
   2  * File:        msi.c
   3  * Purpose:     PCI Message Signaled Interrupt (MSI)
   4  *
   5  * Copyright (C) 2003-2004 Intel
   6  * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
   7  */
   8
   9 #include <linux/err.h>
  10 #include <linux/mm.h>
  11 #include <linux/irq.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/init.h>
  14 #include <linux/ioport.h>
  15 #include <linux/pci.h>
  16 #include <linux/proc_fs.h>
  17 #include <linux/msi.h>
  18
  19 #include <asm/errno.h>
  20 #include <asm/io.h>
  21 #include <asm/smp.h>
  22
  23 #include "pci.h"
  24 #include "msi.h"
  25
  26 static int pci_msi_enable = 1;
  27
  28 static void msi_set_enable(struct pci_dev *dev, int enable)
  29 {
  30         int pos;
  31         u16 control;
  32
  33         pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
  34         if (pos) {
  35                 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
  36                 control &= ~PCI_MSI_FLAGS_ENABLE;
  37                 if (enable)
  38                         control |= PCI_MSI_FLAGS_ENABLE;
  39                 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
  40         }
  41 }
  42
  43 static void msix_set_enable(struct pci_dev *dev, int enable)
  44 {
  45         int pos;
  46         u16 control;
  47
  48         pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
  49         if (pos) {
  50                 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
  51                 control &= ~PCI_MSIX_FLAGS_ENABLE;
  52                 if (enable)
  53                         control |= PCI_MSIX_FLAGS_ENABLE;
  54                 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
  55         }
  56 }
  57
  58 static void msix_flush_writes(unsigned int irq)
  59 {
  60         struct msi_desc *entry;
  61
  62         entry = get_irq_msi(irq);
  63         BUG_ON(!entry || !entry->dev);
  64         switch (entry->msi_attrib.type) {
  65         case PCI_CAP_ID_MSI:
  66                 /* nothing to do */
  67                 break;
  68         case PCI_CAP_ID_MSIX:
  69         {
  70                 int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
  71                         PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
  72                 readl(entry->mask_base + offset);
  73                 break;
  74         }
  75         default:
  76                 BUG();
  77                 break;
  78         }
  79 }
  80
  81 static void msi_set_mask_bit(unsigned int irq, int flag)
  82 {
  83         struct msi_desc *entry;
  84
  85         entry = get_irq_msi(irq);
  86         BUG_ON(!entry || !entry->dev);
  87         switch (entry->msi_attrib.type) {
  88         case PCI_CAP_ID_MSI:
  89                 if (entry->msi_attrib.maskbit) {
  90                         int pos;
  91                         u32 mask_bits;
  92
  93                         pos = (long)entry->mask_base;
  94                         pci_read_config_dword(entry->dev, pos, &mask_bits);
  95                         mask_bits &= ~(1);
  96                         mask_bits |= flag;
  97                         pci_write_config_dword(entry->dev, pos, mask_bits);
  98                 } else {
  99                         msi_set_enable(entry->dev, !flag);
 100                 }
 101                 break;
 102         case PCI_CAP_ID_MSIX:
 103         {
 104                 int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
 105                         PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
 106                 writel(flag, entry->mask_base + offset);
 107                 readl(entry->mask_base + offset);
 108                 break;
 109         }
 110         default:
 111                 BUG();
 112                 break;
 113         }
 114         entry->msi_attrib.masked = !!flag;
 115 }
 116
 117 void read_msi_msg(unsigned int irq, struct msi_msg *msg)
 118 {
 119         struct msi_desc *entry = get_irq_msi(irq);
 120         switch(entry->msi_attrib.type) {
 121         case PCI_CAP_ID_MSI:
 122         {
 123                 struct pci_dev *dev = entry->dev;
 124                 int pos = entry->msi_attrib.pos;
 125                 u16 data;
 126
 127                 pci_read_config_dword(dev, msi_lower_address_reg(pos),
 128                                         &msg->address_lo);
 129                 if (entry->msi_attrib.is_64) {
 130                         pci_read_config_dword(dev, msi_upper_address_reg(pos),
 131                                                 &msg->address_hi);
 132                         pci_read_config_word(dev, msi_data_reg(pos, 1), &data);
 133                 } else {
 134                         msg->address_hi = 0;
 135                         pci_read_config_word(dev, msi_data_reg(pos, 1), &data);
 136                 }
 137                 msg->data = data;
 138                 break;
 139         }
 140         case PCI_CAP_ID_MSIX:
 141         {
 142                 void __iomem *base;
 143                 base = entry->mask_base +
 144                         entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 145
 146                 msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
 147                 msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
 148                 msg->data = readl(base + PCI_MSIX_ENTRY_DATA_OFFSET);
 149                 break;
 150         }
 151         default:
 152                 BUG();
 153         }
 154 }
 155
 156 void write_msi_msg(unsigned int irq, struct msi_msg *msg)
 157 {
 158         struct msi_desc *entry = get_irq_msi(irq);
 159         switch (entry->msi_attrib.type) {
 160         case PCI_CAP_ID_MSI:
 161         {
 162                 struct pci_dev *dev = entry->dev;
 163                 int pos = entry->msi_attrib.pos;
 164
 165                 pci_write_config_dword(dev, msi_lower_address_reg(pos),
 166                                         msg->address_lo);
 167                 if (entry->msi_attrib.is_64) {
 168                         pci_write_config_dword(dev, msi_upper_address_reg(pos),
 169                                                 msg->address_hi);
 170                         pci_write_config_word(dev, msi_data_reg(pos, 1),
 171                                                 msg->data);
 172                 } else {
 173                         pci_write_config_word(dev, msi_data_reg(pos, 0),
 174                                                 msg->data);
 175                 }
 176                 break;
 177         }
 178         case PCI_CAP_ID_MSIX:
 179         {
 180                 void __iomem *base;
 181                 base = entry->mask_base +
 182                         entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 183
 184                 writel(msg->address_lo,
 185                         base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
 186                 writel(msg->address_hi,
 187                         base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
 188                 writel(msg->data, base + PCI_MSIX_ENTRY_DATA_OFFSET);
 189                 break;
 190         }
 191         default:
 192                 BUG();
 193         }
 194         entry->msg = *msg;
 195 }
 196
 197 void mask_msi_irq(unsigned int irq)
 198 {
 199         msi_set_mask_bit(irq, 1);
 200         msix_flush_writes(irq);
 201 }
 202
 203 void unmask_msi_irq(unsigned int irq)
 204 {
 205         msi_set_mask_bit(irq, 0);
 206         msix_flush_writes(irq);
 207 }
 208
 209 static int msi_free_irqs(struct pci_dev* dev);
 210
 211
 212 static struct msi_desc* alloc_msi_entry(void)
 213 {
 214         struct msi_desc *entry;
 215
 216         entry = kzalloc(sizeof(struct msi_desc), GFP_KERNEL);
 217         if (!entry)
 218                 return NULL;
 219
 220         INIT_LIST_HEAD(&entry->list);
 221         entry->irq = 0;
 222         entry->dev = NULL;
 223
 224         return entry;
 225 }
 226
 227 #ifdef CONFIG_PM
 228 static void __pci_restore_msi_state(struct pci_dev *dev)
 229 {
 230         int pos;
 231         u16 control;
 232         struct msi_desc *entry;
 233
 234         if (!dev->msi_enabled)
 235                 return;
 236
 237         entry = get_irq_msi(dev->irq);
 238         pos = entry->msi_attrib.pos;
 239
 240         pci_intx(dev, 0);               /* disable intx */
 241         msi_set_enable(dev, 0);
 242         write_msi_msg(dev->irq, &entry->msg);
 243         if (entry->msi_attrib.maskbit)
 244                 msi_set_mask_bit(dev->irq, entry->msi_attrib.masked);
 245
 246         pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
 247         control &= ~(PCI_MSI_FLAGS_QSIZE | PCI_MSI_FLAGS_ENABLE);
 248         if (entry->msi_attrib.maskbit || !entry->msi_attrib.masked)
 249                 control |= PCI_MSI_FLAGS_ENABLE;
 250         pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
 251 }
 252
 253 static void __pci_restore_msix_state(struct pci_dev *dev)
 254 {
 255         int pos;
 256         struct msi_desc *entry;
 257         u16 control;
 258
 259         if (!dev->msix_enabled)
 260                 return;
 261
 262         /* route the table */
 263         pci_intx(dev, 0);               /* disable intx */
 264         msix_set_enable(dev, 0);
 265
 266         list_for_each_entry(entry, &dev->msi_list, list) {
 267                 write_msi_msg(entry->irq, &entry->msg);
 268                 msi_set_mask_bit(entry->irq, entry->msi_attrib.masked);
 269         }
 270
 271         BUG_ON(list_empty(&dev->msi_list));
 272         entry = list_entry(dev->msi_list.next, struct msi_desc, list);
 273         pos = entry->msi_attrib.pos;
 274         pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
 275         control &= ~PCI_MSIX_FLAGS_MASKALL;
 276         control |= PCI_MSIX_FLAGS_ENABLE;
 277         pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
 278 }
 279
 280 void pci_restore_msi_state(struct pci_dev *dev)
 281 {
 282         __pci_restore_msi_state(dev);
 283         __pci_restore_msix_state(dev);
 284 }
 285 #endif  /* CONFIG_PM */
 286
 287 /**
 288  * msi_capability_init - configure device's MSI capability structure
 289  * @dev: pointer to the pci_dev data structure of MSI device function
 290  *
 291  * Setup the MSI capability structure of device function with a single
 292  * MSI irq, regardless of device function is capable of handling
 293  * multiple messages. A return of zero indicates the successful setup
 294  * of an entry zero with the new MSI irq or non-zero for otherwise.
 295  **/
 296 static int msi_capability_init(struct pci_dev *dev)
 297 {
 298         struct msi_desc *entry;
 299         int pos, ret;
 300         u16 control;
 301
 302         msi_set_enable(dev, 0); /* Ensure msi is disabled as I set it up */
 303
 304         pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
 305         pci_read_config_word(dev, msi_control_reg(pos), &control);
 306         /* MSI Entry Initialization */
 307         entry = alloc_msi_entry();
 308         if (!entry)
 309                 return -ENOMEM;
 310
 311         entry->msi_attrib.type = PCI_CAP_ID_MSI;
 312         entry->msi_attrib.is_64 = is_64bit_address(control);
 313         entry->msi_attrib.entry_nr = 0;
 314         entry->msi_attrib.maskbit = is_mask_bit_support(control);
 315         entry->msi_attrib.masked = 1;
 316         entry->msi_attrib.default_irq = dev->irq;       /* Save IOAPIC IRQ */
 317         entry->msi_attrib.pos = pos;
 318         if (is_mask_bit_support(control)) {
 319                 entry->mask_base = (void __iomem *)(long)msi_mask_bits_reg(pos,
 320                                 is_64bit_address(control));
 321         }
 322         entry->dev = dev;
 323         if (entry->msi_attrib.maskbit) {
 324                 unsigned int maskbits, temp;
 325                 /* All MSIs are unmasked by default, Mask them all */
 326                 pci_read_config_dword(dev,
 327                         msi_mask_bits_reg(pos, is_64bit_address(control)),
 328                         &maskbits);
 329                 temp = (1 << multi_msi_capable(control));
 330                 temp = ((temp - 1) & ~temp);
 331                 maskbits |= temp;
 332                 pci_write_config_dword(dev,
 333                         msi_mask_bits_reg(pos, is_64bit_address(control)),
 334                         maskbits);
 335         }
 336         list_add(&entry->list, &dev->msi_list);
 337
 338         /* Configure MSI capability structure */
 339         ret = arch_setup_msi_irqs(dev, 1, PCI_CAP_ID_MSI);
 340         if (ret) {
 341                 msi_free_irqs(dev);
 342                 return ret;
 343         }
 344
 345         /* Set MSI enabled bits  */
 346         pci_intx(dev, 0);               /* disable intx */
 347         msi_set_enable(dev, 1);
 348         dev->msi_enabled = 1;
 349
 350         dev->irq = entry->irq;
 351         return 0;
 352 }
 353
 354 /**
 355  * msix_capability_init - configure device's MSI-X capability
 356  * @dev: pointer to the pci_dev data structure of MSI-X device function
 357  * @entries: pointer to an array of struct msix_entry entries
 358  * @nvec: number of @entries
 359  *
 360  * Setup the MSI-X capability structure of device function with a
 361  * single MSI-X irq. A return of zero indicates the successful setup of
 362  * requested MSI-X entries with allocated irqs or non-zero for otherwise.
 363  **/
 364 static int msix_capability_init(struct pci_dev *dev,
 365                                 struct msix_entry *entries, int nvec)
 366 {
 367         struct msi_desc *entry;
 368         int pos, i, j, nr_entries, ret;
 369         unsigned long phys_addr;
 370         u32 table_offset;
 371         u16 control;
 372         u8 bir;
 373         void __iomem *base;
 374
 375         msix_set_enable(dev, 0);/* Ensure msix is disabled as I set it up */
 376
 377         pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
 378         /* Request & Map MSI-X table region */
 379         pci_read_config_word(dev, msi_control_reg(pos), &control);
 380         nr_entries = multi_msix_capable(control);
 381
 382         pci_read_config_dword(dev, msix_table_offset_reg(pos), &table_offset);
 383         bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
 384         table_offset &= ~PCI_MSIX_FLAGS_BIRMASK;
 385         phys_addr = pci_resource_start (dev, bir) + table_offset;
 386         base = ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
 387         if (base == NULL)
 388                 return -ENOMEM;
 389
 390         /* MSI-X Table Initialization */
 391         for (i = 0; i < nvec; i++) {
 392                 entry = alloc_msi_entry();
 393                 if (!entry)
 394                         break;
 395
 396                 j = entries[i].entry;
 397                 entry->msi_attrib.type = PCI_CAP_ID_MSIX;
 398                 entry->msi_attrib.is_64 = 1;
 399                 entry->msi_attrib.entry_nr = j;
 400                 entry->msi_attrib.maskbit = 1;
 401                 entry->msi_attrib.masked = 1;
 402                 entry->msi_attrib.default_irq = dev->irq;
 403                 entry->msi_attrib.pos = pos;
 404                 entry->dev = dev;
 405                 entry->mask_base = base;
 406
 407                 list_add(&entry->list, &dev->msi_list);
 408         }
 409
 410         ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
 411         if (ret) {
 412                 int avail = 0;
 413                 list_for_each_entry(entry, &dev->msi_list, list) {
 414                         if (entry->irq != 0) {
 415                                 avail++;
 416                         }
 417                 }
 418
 419                 msi_free_irqs(dev);
 420
 421                 /* If we had some success report the number of irqs
 422                  * we succeeded in setting up.
 423                  */
 424                 if (avail == 0)
 425                         avail = ret;
 426                 return avail;
 427         }
 428
 429         i = 0;
 430         list_for_each_entry(entry, &dev->msi_list, list) {
 431                 entries[i].vector = entry->irq;
 432                 set_irq_msi(entry->irq, entry);
 433                 i++;
 434         }
 435         /* Set MSI-X enabled bits */
 436         pci_intx(dev, 0);               /* disable intx */
 437         msix_set_enable(dev, 1);
 438         dev->msix_enabled = 1;
 439
 440         return 0;
 441 }
 442
 443 /**
 444  * pci_msi_check_device - check whether MSI may be enabled on a device
 445  * @dev: pointer to the pci_dev data structure of MSI device function
 446  * @nvec: how many MSIs have been requested ?
 447  * @type: are we checking for MSI or MSI-X ?
 448  *
 449  * Look at global flags, the device itself, and its parent busses
 450  * to determine if MSI/-X are supported for the device. If MSI/-X is
 451  * supported return 0, else return an error code.
 452  **/
 453 static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type)
 454 {
 455         struct pci_bus *bus;
 456         int ret;
 457
 458         /* MSI must be globally enabled and supported by the device */
 459         if (!pci_msi_enable || !dev || dev->no_msi)
 460                 return -EINVAL;
 461
 462         /*
 463          * You can't ask to have 0 or less MSIs configured.
 464          *  a) it's stupid ..
 465          *  b) the list manipulation code assumes nvec >= 1.
 466          */
 467         if (nvec < 1)
 468                 return -ERANGE;
 469
 470         /* Any bridge which does NOT route MSI transactions from it's
 471          * secondary bus to it's primary bus must set NO_MSI flag on
 472          * the secondary pci_bus.
 473          * We expect only arch-specific PCI host bus controller driver
 474          * or quirks for specific PCI bridges to be setting NO_MSI.
 475          */
 476         for (bus = dev->bus; bus; bus = bus->parent)
 477                 if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
 478                         return -EINVAL;
 479
 480         ret = arch_msi_check_device(dev, nvec, type);
 481         if (ret)
 482                 return ret;
 483
 484         if (!pci_find_capability(dev, type))
 485                 return -EINVAL;
 486
 487         return 0;
 488 }
 489
 490 /**
 491  * pci_enable_msi - configure device's MSI capability structure
 492  * @dev: pointer to the pci_dev data structure of MSI device function
 493  *
 494  * Setup the MSI capability structure of device function with
 495  * a single MSI irq upon its software driver call to request for
 496  * MSI mode enabled on its hardware device function. A return of zero
 497  * indicates the successful setup of an entry zero with the new MSI
 498  * irq or non-zero for otherwise.
 499  **/
 500 int pci_enable_msi(struct pci_dev* dev)
 501 {
 502         int status;
 503
 504         status = pci_msi_check_device(dev, 1, PCI_CAP_ID_MSI);
 505         if (status)
 506                 return status;
 507
 508         WARN_ON(!!dev->msi_enabled);
 509
 510         /* Check whether driver already requested for MSI-X irqs */
 511         if (dev->msix_enabled) {
 512                 printk(KERN_INFO "PCI: %s: Can't enable MSI.  "
 513                         "Device already has MSI-X enabled\n",
 514                         pci_name(dev));
 515                 return -EINVAL;
 516         }
 517         status = msi_capability_init(dev);
 518         return status;
 519 }
 520 EXPORT_SYMBOL(pci_enable_msi);
 521
 522 void pci_disable_msi(struct pci_dev* dev)
 523 {
 524         struct msi_desc *entry;
 525         int default_irq;
 526
 527         if (!pci_msi_enable || !dev || !dev->msi_enabled)
 528                 return;
 529
 530         msi_set_enable(dev, 0);
 531         pci_intx(dev, 1);               /* enable intx */
 532         dev->msi_enabled = 0;
 533
 534         BUG_ON(list_empty(&dev->msi_list));
 535         entry = list_entry(dev->msi_list.next, struct msi_desc, list);
 536         if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
 537                 return;
 538         }
 539
 540         default_irq = entry->msi_attrib.default_irq;
 541         msi_free_irqs(dev);
 542
 543         /* Restore dev->irq to its default pin-assertion irq */
 544         dev->irq = default_irq;
 545 }
 546 EXPORT_SYMBOL(pci_disable_msi);
 547
 548 static int msi_free_irqs(struct pci_dev* dev)
 549 {
 550         struct msi_desc *entry, *tmp;
 551
 552         list_for_each_entry(entry, &dev->msi_list, list)
 553                 BUG_ON(irq_has_action(entry->irq));
 554
 555         arch_teardown_msi_irqs(dev);
 556
 557         list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
 558                 if (entry->msi_attrib.type == PCI_CAP_ID_MSIX) {
 559                         if (list_is_last(&entry->list, &dev->msi_list))
 560                                 iounmap(entry->mask_base);
 561
 562                         writel(1, entry->mask_base + entry->msi_attrib.entry_nr
 563                                   * PCI_MSIX_ENTRY_SIZE
 564                                   + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
 565                 }
 566                 list_del(&entry->list);
 567                 kfree(entry);
 568         }
 569
 570         return 0;
 571 }
 572
 573 /**
 574  * pci_enable_msix - configure device's MSI-X capability structure
 575  * @dev: pointer to the pci_dev data structure of MSI-X device function
 576  * @entries: pointer to an array of MSI-X entries
 577  * @nvec: number of MSI-X irqs requested for allocation by device driver
 578  *
 579  * Setup the MSI-X capability structure of device function with the number
 580  * of requested irqs upon its software driver call to request for
 581  * MSI-X mode enabled on its hardware device function. A return of zero
 582  * indicates the successful configuration of MSI-X capability structure
 583  * with new allocated MSI-X irqs. A return of < 0 indicates a failure.
 584  * Or a return of > 0 indicates that driver request is exceeding the number
 585  * of irqs available. Driver should use the returned value to re-send
 586  * its request.
 587  **/
 588 int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
 589 {
 590         int status, pos, nr_entries;
 591         int i, j;
 592         u16 control;
 593
 594         if (!entries)
 595                 return -EINVAL;
 596
 597         status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX);
 598         if (status)
 599                 return status;
 600
 601         pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
 602         pci_read_config_word(dev, msi_control_reg(pos), &control);
 603         nr_entries = multi_msix_capable(control);
 604         if (nvec > nr_entries)
 605                 return -EINVAL;
 606
 607         /* Check for any invalid entries */
 608         for (i = 0; i < nvec; i++) {
 609                 if (entries[i].entry >= nr_entries)
 610                         return -EINVAL;         /* invalid entry */
 611                 for (j = i + 1; j < nvec; j++) {
 612                         if (entries[i].entry == entries[j].entry)
 613                                 return -EINVAL; /* duplicate entry */
 614                 }
 615         }
 616         WARN_ON(!!dev->msix_enabled);
 617
 618         /* Check whether driver already requested for MSI irq */
 619         if (dev->msi_enabled) {
 620                 printk(KERN_INFO "PCI: %s: Can't enable MSI-X.  "
 621                        "Device already has an MSI irq assigned\n",
 622                        pci_name(dev));
 623                 return -EINVAL;
 624         }
 625         status = msix_capability_init(dev, entries, nvec);
 626         return status;
 627 }
 628 EXPORT_SYMBOL(pci_enable_msix);
 629
 630 static void msix_free_all_irqs(struct pci_dev *dev)
 631 {
 632         msi_free_irqs(dev);
 633 }
 634
 635 void pci_disable_msix(struct pci_dev* dev)
 636 {
 637         if (!pci_msi_enable || !dev || !dev->msix_enabled)
 638                 return;
 639
 640         msix_set_enable(dev, 0);
 641         pci_intx(dev, 1);               /* enable intx */
 642         dev->msix_enabled = 0;
 643
 644         msix_free_all_irqs(dev);
 645 }
 646 EXPORT_SYMBOL(pci_disable_msix);
 647
 648 /**
 649  * msi_remove_pci_irq_vectors - reclaim MSI(X) irqs to unused state
 650  * @dev: pointer to the pci_dev data structure of MSI(X) device function
 651  *
 652  * Being called during hotplug remove, from which the device function
 653  * is hot-removed. All previous assigned MSI/MSI-X irqs, if
 654  * allocated for this device function, are reclaimed to unused state,
 655  * which may be used later on.
 656  **/
 657 void msi_remove_pci_irq_vectors(struct pci_dev* dev)
 658 {
 659         if (!pci_msi_enable || !dev)
 660                 return;
 661
 662         if (dev->msi_enabled)
 663                 msi_free_irqs(dev);
 664
 665         if (dev->msix_enabled)
 666                 msix_free_all_irqs(dev);
 667 }
 668
 669 void pci_no_msi(void)
 670 {
 671         pci_msi_enable = 0;
 672 }
 673
 674 void pci_msi_init_pci_dev(struct pci_dev *dev)
 675 {
 676         INIT_LIST_HEAD(&dev->msi_list);
 677 }
 678
 679
 680 /* Arch hooks */
 681
 682 int __attribute__ ((weak))
 683 arch_msi_check_device(struct pci_dev* dev, int nvec, int type)
 684 {
 685         return 0;
 686 }
 687
 688 int __attribute__ ((weak))
 689 arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *entry)
 690 {
 691         return 0;
 692 }
 693
 694 int __attribute__ ((weak))
 695 arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 696 {
 697         struct msi_desc *entry;
 698         int ret;
 699
 700         list_for_each_entry(entry, &dev->msi_list, list) {
 701                 ret = arch_setup_msi_irq(dev, entry);
 702                 if (ret)
 703                         return ret;
 704         }
 705
 706         return 0;
 707 }
 708
 709 void __attribute__ ((weak)) arch_teardown_msi_irq(unsigned int irq)
 710 {
 711         return;
 712 }
 713
 714 void __attribute__ ((weak))
 715 arch_teardown_msi_irqs(struct pci_dev *dev)
 716 {
 717         struct msi_desc *entry;
 718
 719         list_for_each_entry(entry, &dev->msi_list, list) {
 720                 if (entry->irq != 0)
 721                         arch_teardown_msi_irq(entry->irq);
 722         }
 723 }