arch/x86/pci/fixup.c

   1 /*
   2  * Exceptions for specific devices. Usually work-arounds for fatal design flaws.
   3  */
   4
   5 #include <linux/delay.h>
   6 #include <linux/dmi.h>
   7 #include <linux/pci.h>
   8 #include <linux/init.h>
   9 #include "pci.h"
  10
  11
  12 static void __devinit pci_fixup_i450nx(struct pci_dev *d)
  13 {
  14         /*
  15          * i450NX -- Find and scan all secondary buses on all PXB's.
  16          */
  17         int pxb, reg;
  18         u8 busno, suba, subb;
  19
  20         dev_warn(&d->dev, "Searching for i450NX host bridges\n");
  21         reg = 0xd0;
  22         for(pxb = 0; pxb < 2; pxb++) {
  23                 pci_read_config_byte(d, reg++, &busno);
  24                 pci_read_config_byte(d, reg++, &suba);
  25                 pci_read_config_byte(d, reg++, &subb);
  26                 DBG("i450NX PXB %d: %02x/%02x/%02x\n", pxb, busno, suba, subb);
  27                 if (busno)
  28                         pci_scan_bus_with_sysdata(busno);       /* Bus A */
  29                 if (suba < subb)
  30                         pci_scan_bus_with_sysdata(suba+1);      /* Bus B */
  31         }
  32         pcibios_last_bus = -1;
  33 }
  34 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82451NX, pci_fixup_i450nx);
  35
  36 static void __devinit pci_fixup_i450gx(struct pci_dev *d)
  37 {
  38         /*
  39          * i450GX and i450KX -- Find and scan all secondary buses.
  40          * (called separately for each PCI bridge found)
  41          */
  42         u8 busno;
  43         pci_read_config_byte(d, 0x4a, &busno);
  44         dev_info(&d->dev, "i440KX/GX host bridge; secondary bus %02x\n", busno);
  45         pci_scan_bus_with_sysdata(busno);
  46         pcibios_last_bus = -1;
  47 }
  48 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82454GX, pci_fixup_i450gx);
  49
  50 static void __devinit  pci_fixup_umc_ide(struct pci_dev *d)
  51 {
  52         /*
  53          * UM8886BF IDE controller sets region type bits incorrectly,
  54          * therefore they look like memory despite of them being I/O.
  55          */
  56         int i;
  57
  58         dev_warn(&d->dev, "Fixing base address flags\n");
  59         for(i = 0; i < 4; i++)
  60                 d->resource[i].flags |= PCI_BASE_ADDRESS_SPACE_IO;
  61 }
  62 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_UMC, PCI_DEVICE_ID_UMC_UM8886BF, pci_fixup_umc_ide);
  63
  64 static void __devinit  pci_fixup_ncr53c810(struct pci_dev *d)
  65 {
  66         /*
  67          * NCR 53C810 returns class code 0 (at least on some systems).
  68          * Fix class to be PCI_CLASS_STORAGE_SCSI
  69          */
  70         if (!d->class) {
  71                 dev_warn(&d->dev, "Fixing NCR 53C810 class code\n");
  72                 d->class = PCI_CLASS_STORAGE_SCSI << 8;
  73         }
  74 }
  75 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NCR, PCI_DEVICE_ID_NCR_53C810, pci_fixup_ncr53c810);
  76
  77 static void __devinit  pci_fixup_latency(struct pci_dev *d)
  78 {
  79         /*
  80          *  SiS 5597 and 5598 chipsets require latency timer set to
  81          *  at most 32 to avoid lockups.
  82          */
  83         dev_dbg(&d->dev, "Setting max latency to 32\n");
  84         pcibios_max_latency = 32;
  85 }
  86 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_5597, pci_fixup_latency);
  87 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_5598, pci_fixup_latency);
  88
  89 static void __devinit pci_fixup_piix4_acpi(struct pci_dev *d)
  90 {
  91         /*
  92          * PIIX4 ACPI device: hardwired IRQ9
  93          */
  94         d->irq = 9;
  95 }
  96 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3, pci_fixup_piix4_acpi);
  97
  98 /*
  99  * Addresses issues with problems in the memory write queue timer in
 100  * certain VIA Northbridges.  This bugfix is per VIA's specifications,
 101  * except for the KL133/KM133: clearing bit 5 on those Northbridges seems
 102  * to trigger a bug in its integrated ProSavage video card, which
 103  * causes screen corruption.  We only clear bits 6 and 7 for that chipset,
 104  * until VIA can provide us with definitive information on why screen
 105  * corruption occurs, and what exactly those bits do.
 106  *
 107  * VIA 8363,8622,8361 Northbridges:
 108  *  - bits  5, 6, 7 at offset 0x55 need to be turned off
 109  * VIA 8367 (KT266x) Northbridges:
 110  *  - bits  5, 6, 7 at offset 0x95 need to be turned off
 111  * VIA 8363 rev 0x81/0x84 (KL133/KM133) Northbridges:
 112  *  - bits     6, 7 at offset 0x55 need to be turned off
 113  */
 114
 115 #define VIA_8363_KL133_REVISION_ID 0x81
 116 #define VIA_8363_KM133_REVISION_ID 0x84
 117
 118 static void pci_fixup_via_northbridge_bug(struct pci_dev *d)
 119 {
 120         u8 v;
 121         int where = 0x55;
 122         int mask = 0x1f; /* clear bits 5, 6, 7 by default */
 123
 124         if (d->device == PCI_DEVICE_ID_VIA_8367_0) {
 125                 /* fix pci bus latency issues resulted by NB bios error
 126                    it appears on bug free^Wreduced kt266x's bios forces
 127                    NB latency to zero */
 128                 pci_write_config_byte(d, PCI_LATENCY_TIMER, 0);
 129
 130                 where = 0x95; /* the memory write queue timer register is
 131                                 different for the KT266x's: 0x95 not 0x55 */
 132         } else if (d->device == PCI_DEVICE_ID_VIA_8363_0 &&
 133                         (d->revision == VIA_8363_KL133_REVISION_ID ||
 134                         d->revision == VIA_8363_KM133_REVISION_ID)) {
 135                         mask = 0x3f; /* clear only bits 6 and 7; clearing bit 5
 136                                         causes screen corruption on the KL133/KM133 */
 137         }
 138
 139         pci_read_config_byte(d, where, &v);
 140         if (v & ~mask) {
 141                 dev_warn(&d->dev, "Disabling VIA memory write queue (PCI ID %04x, rev %02x): [%02x] %02x & %02x -> %02x\n", \
 142                         d->device, d->revision, where, v, mask, v & mask);
 143                 v &= mask;
 144                 pci_write_config_byte(d, where, v);
 145         }
 146 }
 147 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8363_0, pci_fixup_via_northbridge_bug);
 148 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8622, pci_fixup_via_northbridge_bug);
 149 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8361, pci_fixup_via_northbridge_bug);
 150 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8367_0, pci_fixup_via_northbridge_bug);
 151 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8363_0, pci_fixup_via_northbridge_bug);
 152 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8622, pci_fixup_via_northbridge_bug);
 153 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8361, pci_fixup_via_northbridge_bug);
 154 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8367_0, pci_fixup_via_northbridge_bug);
 155
 156 /*
 157  * For some reasons Intel decided that certain parts of their
 158  * 815, 845 and some other chipsets must look like PCI-to-PCI bridges
 159  * while they are obviously not. The 82801 family (AA, AB, BAM/CAM,
 160  * BA/CA/DB and E) PCI bridges are actually HUB-to-PCI ones, according
 161  * to Intel terminology. These devices do forward all addresses from
 162  * system to PCI bus no matter what are their window settings, so they are
 163  * "transparent" (or subtractive decoding) from programmers point of view.
 164  */
 165 static void __devinit pci_fixup_transparent_bridge(struct pci_dev *dev)
 166 {
 167         if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI &&
 168             (dev->device & 0xff00) == 0x2400)
 169                 dev->transparent = 1;
 170 }
 171 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_fixup_transparent_bridge);
 172
 173 /*
 174  * Fixup for C1 Halt Disconnect problem on nForce2 systems.
 175  *
 176  * From information provided by "Allen Martin" <AMartin@nvidia.com>:
 177  *
 178  * A hang is caused when the CPU generates a very fast CONNECT/HALT cycle
 179  * sequence.  Workaround is to set the SYSTEM_IDLE_TIMEOUT to 80 ns.
 180  * This allows the state-machine and timer to return to a proper state within
 181  * 80 ns of the CONNECT and probe appearing together.  Since the CPU will not
 182  * issue another HALT within 80 ns of the initial HALT, the failure condition
 183  * is avoided.
 184  */
 185 static void pci_fixup_nforce2(struct pci_dev *dev)
 186 {
 187         u32 val;
 188
 189         /*
 190          * Chip  Old value   New value
 191          * C17   0x1F0FFF01  0x1F01FF01
 192          * C18D  0x9F0FFF01  0x9F01FF01
 193          *
 194          * Northbridge chip version may be determined by
 195          * reading the PCI revision ID (0xC1 or greater is C18D).
 196          */
 197         pci_read_config_dword(dev, 0x6c, &val);
 198
 199         /*
 200          * Apply fixup if needed, but don't touch disconnect state
 201          */
 202         if ((val & 0x00FF0000) != 0x00010000) {
 203                 dev_warn(&dev->dev, "nForce2 C1 Halt Disconnect fixup\n");
 204                 pci_write_config_dword(dev, 0x6c, (val & 0xFF00FFFF) | 0x00010000);
 205         }
 206 }
 207 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2, pci_fixup_nforce2);
 208 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2, pci_fixup_nforce2);
 209
 210 /* Max PCI Express root ports */
 211 #define MAX_PCIEROOT    6
 212 static int quirk_aspm_offset[MAX_PCIEROOT << 3];
 213
 214 #define GET_INDEX(a, b) ((((a) - PCI_DEVICE_ID_INTEL_MCH_PA) << 3) + ((b) & 7))
 215
 216 static int quirk_pcie_aspm_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
 217 {
 218         return raw_pci_ops->read(0, bus->number, devfn, where, size, value);
 219 }
 220
 221 /*
 222  * Replace the original pci bus ops for write with a new one that will filter
 223  * the request to insure ASPM cannot be enabled.
 224  */
 225 static int quirk_pcie_aspm_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
 226 {
 227         u8 offset;
 228
 229         offset = quirk_aspm_offset[GET_INDEX(bus->self->device, devfn)];
 230
 231         if ((offset) && (where == offset))
 232                 value = value & 0xfffffffc;
 233
 234         return raw_pci_ops->write(0, bus->number, devfn, where, size, value);
 235 }
 236
 237 static struct pci_ops quirk_pcie_aspm_ops = {
 238         .read = quirk_pcie_aspm_read,
 239         .write = quirk_pcie_aspm_write,
 240 };
 241
 242 /*
 243  * Prevents PCI Express ASPM (Active State Power Management) being enabled.
 244  *
 245  * Save the register offset, where the ASPM control bits are located,
 246  * for each PCI Express device that is in the device list of
 247  * the root port in an array for fast indexing. Replace the bus ops
 248  * with the modified one.
 249  */
 250 static void pcie_rootport_aspm_quirk(struct pci_dev *pdev)
 251 {
 252         int cap_base, i;
 253         struct pci_bus  *pbus;
 254         struct pci_dev *dev;
 255
 256         if ((pbus = pdev->subordinate) == NULL)
 257                 return;
 258
 259         /*
 260          * Check if the DID of pdev matches one of the six root ports. This
 261          * check is needed in the case this function is called directly by the
 262          * hot-plug driver.
 263          */
 264         if ((pdev->device < PCI_DEVICE_ID_INTEL_MCH_PA) ||
 265             (pdev->device > PCI_DEVICE_ID_INTEL_MCH_PC1))
 266                 return;
 267
 268         if (list_empty(&pbus->devices)) {
 269                 /*
 270                  * If no device is attached to the root port at power-up or
 271                  * after hot-remove, the pbus->devices is empty and this code
 272                  * will set the offsets to zero and the bus ops to parent's bus
 273                  * ops, which is unmodified.
 274                  */
 275                 for (i = GET_INDEX(pdev->device, 0); i <= GET_INDEX(pdev->device, 7); ++i)
 276                         quirk_aspm_offset[i] = 0;
 277
 278                 pbus->ops = pbus->parent->ops;
 279         } else {
 280                 /*
 281                  * If devices are attached to the root port at power-up or
 282                  * after hot-add, the code loops through the device list of
 283                  * each root port to save the register offsets and replace the
 284                  * bus ops.
 285                  */
 286                 list_for_each_entry(dev, &pbus->devices, bus_list) {
 287                         /* There are 0 to 8 devices attached to this bus */
 288                         cap_base = pci_find_capability(dev, PCI_CAP_ID_EXP);
 289                         quirk_aspm_offset[GET_INDEX(pdev->device, dev->devfn)] = cap_base + 0x10;
 290                 }
 291                 pbus->ops = &quirk_pcie_aspm_ops;
 292         }
 293 }
 294 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PA,     pcie_rootport_aspm_quirk);
 295 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PA1,    pcie_rootport_aspm_quirk);
 296 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PB,     pcie_rootport_aspm_quirk);
 297 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PB1,    pcie_rootport_aspm_quirk);
 298 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PC,     pcie_rootport_aspm_quirk);
 299 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_MCH_PC1,    pcie_rootport_aspm_quirk);
 300
 301 /*
 302  * Fixup to mark boot BIOS video selected by BIOS before it changes
 303  *
 304  * From information provided by "Jon Smirl" <jonsmirl@gmail.com>
 305  *
 306  * The standard boot ROM sequence for an x86 machine uses the BIOS
 307  * to select an initial video card for boot display. This boot video
 308  * card will have it's BIOS copied to C0000 in system RAM.
 309  * IORESOURCE_ROM_SHADOW is used to associate the boot video
 310  * card with this copy. On laptops this copy has to be used since
 311  * the main ROM may be compressed or combined with another image.
 312  * See pci_map_rom() for use of this flag. IORESOURCE_ROM_SHADOW
 313  * is marked here since the boot video device will be the only enabled
 314  * video device at this point.
 315  */
 316
 317 static void __devinit pci_fixup_video(struct pci_dev *pdev)
 318 {
 319         struct pci_dev *bridge;
 320         struct pci_bus *bus;
 321         u16 config;
 322
 323         if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
 324                 return;
 325
 326         /* Is VGA routed to us? */
 327         bus = pdev->bus;
 328         while (bus) {
 329                 bridge = bus->self;
 330
 331                 /*
 332                  * From information provided by
 333                  * "David Miller" <davem@davemloft.net>
 334                  * The bridge control register is valid for PCI header
 335                  * type BRIDGE, or CARDBUS. Host to PCI controllers use
 336                  * PCI header type NORMAL.
 337                  */
 338                 if (bridge
 339                     && ((bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE)
 340                        || (bridge->hdr_type == PCI_HEADER_TYPE_CARDBUS))) {
 341                         pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
 342                                                 &config);
 343                         if (!(config & PCI_BRIDGE_CTL_VGA))
 344                                 return;
 345                 }
 346                 bus = bus->parent;
 347         }
 348         pci_read_config_word(pdev, PCI_COMMAND, &config);
 349         if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
 350                 pdev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_SHADOW;
 351                 dev_printk(KERN_DEBUG, &pdev->dev, "Boot video device\n");
 352         }
 353 }
 354 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_video);
 355
 356
 357 static struct dmi_system_id __devinitdata msi_k8t_dmi_table[] = {
 358         {
 359                 .ident = "MSI-K8T-Neo2Fir",
 360                 .matches = {
 361                         DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
 362                         DMI_MATCH(DMI_PRODUCT_NAME, "MS-6702E"),
 363                 },
 364         },
 365         {}
 366 };
 367
 368 /*
 369  * The AMD-Athlon64 board MSI "K8T Neo2-FIR" disables the onboard sound
 370  * card if a PCI-soundcard is added.
 371  *
 372  * The BIOS only gives options "DISABLED" and "AUTO". This code sets
 373  * the corresponding register-value to enable the soundcard.
 374  *
 375  * The soundcard is only enabled, if the mainborad is identified
 376  * via DMI-tables and the soundcard is detected to be off.
 377  */
 378 static void __devinit pci_fixup_msi_k8t_onboard_sound(struct pci_dev *dev)
 379 {
 380         unsigned char val;
 381         if (!dmi_check_system(msi_k8t_dmi_table))
 382                 return; /* only applies to MSI K8T Neo2-FIR */
 383
 384         pci_read_config_byte(dev, 0x50, &val);
 385         if (val & 0x40) {
 386                 pci_write_config_byte(dev, 0x50, val & (~0x40));
 387
 388                 /* verify the change for status output */
 389                 pci_read_config_byte(dev, 0x50, &val);
 390                 if (val & 0x40)
 391                         dev_info(&dev->dev, "Detected MSI K8T Neo2-FIR; "
 392                                         "can't enable onboard soundcard!\n");
 393                 else
 394                         dev_info(&dev->dev, "Detected MSI K8T Neo2-FIR; "
 395                                         "enabled onboard soundcard\n");
 396         }
 397 }
 398 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237,
 399                 pci_fixup_msi_k8t_onboard_sound);
 400 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237,
 401                 pci_fixup_msi_k8t_onboard_sound);
 402
 403 /*
 404  * Some Toshiba laptops need extra code to enable their TI TSB43AB22/A.
 405  *
 406  * We pretend to bring them out of full D3 state, and restore the proper
 407  * IRQ, PCI cache line size, and BARs, otherwise the device won't function
 408  * properly.  In some cases, the device will generate an interrupt on
 409  * the wrong IRQ line, causing any devices sharing the line it's
 410  * *supposed* to use to be disabled by the kernel's IRQ debug code.
 411  */
 412 static u16 toshiba_line_size;
 413
 414 static struct dmi_system_id __devinitdata toshiba_ohci1394_dmi_table[] = {
 415         {
 416                 .ident = "Toshiba PS5 based laptop",
 417                 .matches = {
 418                         DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 419                         DMI_MATCH(DMI_PRODUCT_VERSION, "PS5"),
 420                 },
 421         },
 422         {
 423                 .ident = "Toshiba PSM4 based laptop",
 424                 .matches = {
 425                         DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 426                         DMI_MATCH(DMI_PRODUCT_VERSION, "PSM4"),
 427                 },
 428         },
 429         {
 430                 .ident = "Toshiba A40 based laptop",
 431                 .matches = {
 432                         DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 433                         DMI_MATCH(DMI_PRODUCT_VERSION, "PSA40U"),
 434                 },
 435         },
 436         { }
 437 };
 438
 439 static void __devinit pci_pre_fixup_toshiba_ohci1394(struct pci_dev *dev)
 440 {
 441         if (!dmi_check_system(toshiba_ohci1394_dmi_table))
 442                 return; /* only applies to certain Toshibas (so far) */
 443
 444         dev->current_state = PCI_D3cold;
 445         pci_read_config_word(dev, PCI_CACHE_LINE_SIZE, &toshiba_line_size);
 446 }
 447 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TI, 0x8032,
 448                          pci_pre_fixup_toshiba_ohci1394);
 449
 450 static void __devinit pci_post_fixup_toshiba_ohci1394(struct pci_dev *dev)
 451 {
 452         if (!dmi_check_system(toshiba_ohci1394_dmi_table))
 453                 return; /* only applies to certain Toshibas (so far) */
 454
 455         /* Restore config space on Toshiba laptops */
 456         pci_write_config_word(dev, PCI_CACHE_LINE_SIZE, toshiba_line_size);
 457         pci_read_config_byte(dev, PCI_INTERRUPT_LINE, (u8 *)&dev->irq);
 458         pci_write_config_dword(dev, PCI_BASE_ADDRESS_0,
 459                                pci_resource_start(dev, 0));
 460         pci_write_config_dword(dev, PCI_BASE_ADDRESS_1,
 461                                pci_resource_start(dev, 1));
 462 }
 463 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_TI, 0x8032,
 464                          pci_post_fixup_toshiba_ohci1394);
 465
 466
 467 /*
 468  * Prevent the BIOS trapping accesses to the Cyrix CS5530A video device
 469  * configuration space.
 470  */
 471 static void pci_early_fixup_cyrix_5530(struct pci_dev *dev)
 472 {
 473         u8 r;
 474         /* clear 'F4 Video Configuration Trap' bit */
 475         pci_read_config_byte(dev, 0x42, &r);
 476         r &= 0xfd;
 477         pci_write_config_byte(dev, 0x42, r);
 478 }
 479 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY,
 480                         pci_early_fixup_cyrix_5530);
 481 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY,
 482                         pci_early_fixup_cyrix_5530);
 483
 484 /*
 485  * Siemens Nixdorf AG FSC Multiprocessor Interrupt Controller:
 486  * prevent update of the BAR0, which doesn't look like a normal BAR.
 487  */
 488 static void __devinit pci_siemens_interrupt_controller(struct pci_dev *dev)
 489 {
 490         dev->resource[0].flags |= IORESOURCE_PCI_FIXED;
 491 }
 492 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SIEMENS, 0x0015,
 493                           pci_siemens_interrupt_controller);