drivers/pci/pci-sysfs.c

   1 /*
   2  * drivers/pci/pci-sysfs.c
   3  *
   4  * (C) Copyright 2002-2004 Greg Kroah-Hartman <greg@kroah.com>
   5  * (C) Copyright 2002-2004 IBM Corp.
   6  * (C) Copyright 2003 Matthew Wilcox
   7  * (C) Copyright 2003 Hewlett-Packard
   8  * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
   9  * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
  10  *
  11  * File attributes for PCI devices
  12  *
  13  * Modeled after usb's driverfs.c
  14  *
  15  */
  16
  17
  18 #include <linux/kernel.h>
  19 #include <linux/pci.h>
  20 #include <linux/stat.h>
  21 #include <linux/topology.h>
  22 #include <linux/mm.h>
  23
  24 #include "pci.h"
  25
  26 static int sysfs_initialized;   /* = 0 */
  27
  28 /* show configuration fields */
  29 #define pci_config_attr(field, format_string)                           \
  30 static ssize_t                                                          \
  31 field##_show(struct device *dev, struct device_attribute *attr, char *buf)                              \
  32 {                                                                       \
  33         struct pci_dev *pdev;                                           \
  34                                                                         \
  35         pdev = to_pci_dev (dev);                                        \
  36         return sprintf (buf, format_string, pdev->field);               \
  37 }
  38
  39 pci_config_attr(vendor, "0x%04x\n");
  40 pci_config_attr(device, "0x%04x\n");
  41 pci_config_attr(subsystem_vendor, "0x%04x\n");
  42 pci_config_attr(subsystem_device, "0x%04x\n");
  43 pci_config_attr(class, "0x%06x\n");
  44 pci_config_attr(irq, "%u\n");
  45 pci_config_attr(is_enabled, "%u\n");
  46
  47 static ssize_t broken_parity_status_show(struct device *dev,
  48                                          struct device_attribute *attr,
  49                                          char *buf)
  50 {
  51         struct pci_dev *pdev = to_pci_dev(dev);
  52         return sprintf (buf, "%u\n", pdev->broken_parity_status);
  53 }
  54
  55 static ssize_t broken_parity_status_store(struct device *dev,
  56                                           struct device_attribute *attr,
  57                                           const char *buf, size_t count)
  58 {
  59         struct pci_dev *pdev = to_pci_dev(dev);
  60         ssize_t consumed = -EINVAL;
  61
  62         if ((count > 0) && (*buf == '0' || *buf == '1')) {
  63                 pdev->broken_parity_status = *buf == '1' ? 1 : 0;
  64                 consumed = count;
  65         }
  66         return consumed;
  67 }
  68
  69 static ssize_t local_cpus_show(struct device *dev,
  70                         struct device_attribute *attr, char *buf)
  71 {
  72         cpumask_t mask;
  73         int len;
  74
  75         mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
  76         len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
  77         strcat(buf,"\n");
  78         return 1+len;
  79 }
  80
  81 /* show resources */
  82 static ssize_t
  83 resource_show(struct device * dev, struct device_attribute *attr, char * buf)
  84 {
  85         struct pci_dev * pci_dev = to_pci_dev(dev);
  86         char * str = buf;
  87         int i;
  88         int max = 7;
  89         resource_size_t start, end;
  90
  91         if (pci_dev->subordinate)
  92                 max = DEVICE_COUNT_RESOURCE;
  93
  94         for (i = 0; i < max; i++) {
  95                 struct resource *res =  &pci_dev->resource[i];
  96                 pci_resource_to_user(pci_dev, i, res, &start, &end);
  97                 str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
  98                                (unsigned long long)start,
  99                                (unsigned long long)end,
 100                                (unsigned long long)res->flags);
 101         }
 102         return (str - buf);
 103 }
 104
 105 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
 106 {
 107         struct pci_dev *pci_dev = to_pci_dev(dev);
 108
 109         return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x\n",
 110                        pci_dev->vendor, pci_dev->device,
 111                        pci_dev->subsystem_vendor, pci_dev->subsystem_device,
 112                        (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
 113                        (u8)(pci_dev->class));
 114 }
 115 static ssize_t
 116 is_enabled_store(struct device *dev, struct device_attribute *attr,
 117                 const char *buf, size_t count)
 118 {
 119         struct pci_dev *pdev = to_pci_dev(dev);
 120
 121         /* this can crash the machine when done on the "wrong" device */
 122         if (!capable(CAP_SYS_ADMIN))
 123                 return count;
 124
 125         if (*buf == '0')
 126                 pci_disable_device(pdev);
 127
 128         if (*buf == '1')
 129                 pci_enable_device(pdev);
 130
 131         return count;
 132 }
 133
 134
 135 struct device_attribute pci_dev_attrs[] = {
 136         __ATTR_RO(resource),
 137         __ATTR_RO(vendor),
 138         __ATTR_RO(device),
 139         __ATTR_RO(subsystem_vendor),
 140         __ATTR_RO(subsystem_device),
 141         __ATTR_RO(class),
 142         __ATTR_RO(irq),
 143         __ATTR_RO(local_cpus),
 144         __ATTR_RO(modalias),
 145         __ATTR(enable, 0600, is_enabled_show, is_enabled_store),
 146         __ATTR(broken_parity_status,(S_IRUGO|S_IWUSR),
 147                 broken_parity_status_show,broken_parity_status_store),
 148         __ATTR_NULL,
 149 };
 150
 151 static ssize_t
 152 pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 153 {
 154         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 155         unsigned int size = 64;
 156         loff_t init_off = off;
 157         u8 *data = (u8*) buf;
 158
 159         /* Several chips lock up trying to read undefined config space */
 160         if (capable(CAP_SYS_ADMIN)) {
 161                 size = dev->cfg_size;
 162         } else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 163                 size = 128;
 164         }
 165
 166         if (off > size)
 167                 return 0;
 168         if (off + count > size) {
 169                 size -= off;
 170                 count = size;
 171         } else {
 172                 size = count;
 173         }
 174
 175         if ((off & 1) && size) {
 176                 u8 val;
 177                 pci_user_read_config_byte(dev, off, &val);
 178                 data[off - init_off] = val;
 179                 off++;
 180                 size--;
 181         }
 182
 183         if ((off & 3) && size > 2) {
 184                 u16 val;
 185                 pci_user_read_config_word(dev, off, &val);
 186                 data[off - init_off] = val & 0xff;
 187                 data[off - init_off + 1] = (val >> 8) & 0xff;
 188                 off += 2;
 189                 size -= 2;
 190         }
 191
 192         while (size > 3) {
 193                 u32 val;
 194                 pci_user_read_config_dword(dev, off, &val);
 195                 data[off - init_off] = val & 0xff;
 196                 data[off - init_off + 1] = (val >> 8) & 0xff;
 197                 data[off - init_off + 2] = (val >> 16) & 0xff;
 198                 data[off - init_off + 3] = (val >> 24) & 0xff;
 199                 off += 4;
 200                 size -= 4;
 201         }
 202
 203         if (size >= 2) {
 204                 u16 val;
 205                 pci_user_read_config_word(dev, off, &val);
 206                 data[off - init_off] = val & 0xff;
 207                 data[off - init_off + 1] = (val >> 8) & 0xff;
 208                 off += 2;
 209                 size -= 2;
 210         }
 211
 212         if (size > 0) {
 213                 u8 val;
 214                 pci_user_read_config_byte(dev, off, &val);
 215                 data[off - init_off] = val;
 216                 off++;
 217                 --size;
 218         }
 219
 220         return count;
 221 }
 222
 223 static ssize_t
 224 pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 225 {
 226         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 227         unsigned int size = count;
 228         loff_t init_off = off;
 229         u8 *data = (u8*) buf;
 230
 231         if (off > dev->cfg_size)
 232                 return 0;
 233         if (off + count > dev->cfg_size) {
 234                 size = dev->cfg_size - off;
 235                 count = size;
 236         }
 237
 238         if ((off & 1) && size) {
 239                 pci_user_write_config_byte(dev, off, data[off - init_off]);
 240                 off++;
 241                 size--;
 242         }
 243
 244         if ((off & 3) && size > 2) {
 245                 u16 val = data[off - init_off];
 246                 val |= (u16) data[off - init_off + 1] << 8;
 247                 pci_user_write_config_word(dev, off, val);
 248                 off += 2;
 249                 size -= 2;
 250         }
 251
 252         while (size > 3) {
 253                 u32 val = data[off - init_off];
 254                 val |= (u32) data[off - init_off + 1] << 8;
 255                 val |= (u32) data[off - init_off + 2] << 16;
 256                 val |= (u32) data[off - init_off + 3] << 24;
 257                 pci_user_write_config_dword(dev, off, val);
 258                 off += 4;
 259                 size -= 4;
 260         }
 261
 262         if (size >= 2) {
 263                 u16 val = data[off - init_off];
 264                 val |= (u16) data[off - init_off + 1] << 8;
 265                 pci_user_write_config_word(dev, off, val);
 266                 off += 2;
 267                 size -= 2;
 268         }
 269
 270         if (size) {
 271                 pci_user_write_config_byte(dev, off, data[off - init_off]);
 272                 off++;
 273                 --size;
 274         }
 275
 276         return count;
 277 }
 278
 279 #ifdef HAVE_PCI_LEGACY
 280 /**
 281  * pci_read_legacy_io - read byte(s) from legacy I/O port space
 282  * @kobj: kobject corresponding to file to read from
 283  * @buf: buffer to store results
 284  * @off: offset into legacy I/O port space
 285  * @count: number of bytes to read
 286  *
 287  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 288  * callback routine (pci_legacy_read).
 289  */
 290 ssize_t
 291 pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 292 {
 293         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 294                                                       struct class_device,
 295                                                       kobj));
 296
 297         /* Only support 1, 2 or 4 byte accesses */
 298         if (count != 1 && count != 2 && count != 4)
 299                 return -EINVAL;
 300
 301         return pci_legacy_read(bus, off, (u32 *)buf, count);
 302 }
 303
 304 /**
 305  * pci_write_legacy_io - write byte(s) to legacy I/O port space
 306  * @kobj: kobject corresponding to file to read from
 307  * @buf: buffer containing value to be written
 308  * @off: offset into legacy I/O port space
 309  * @count: number of bytes to write
 310  *
 311  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 312  * callback routine (pci_legacy_write).
 313  */
 314 ssize_t
 315 pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 316 {
 317         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 318                                                       struct class_device,
 319                                                       kobj));
 320         /* Only support 1, 2 or 4 byte accesses */
 321         if (count != 1 && count != 2 && count != 4)
 322                 return -EINVAL;
 323
 324         return pci_legacy_write(bus, off, *(u32 *)buf, count);
 325 }
 326
 327 /**
 328  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
 329  * @kobj: kobject corresponding to device to be mapped
 330  * @attr: struct bin_attribute for this file
 331  * @vma: struct vm_area_struct passed to mmap
 332  *
 333  * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap
 334  * legacy memory space (first meg of bus space) into application virtual
 335  * memory space.
 336  */
 337 int
 338 pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
 339                     struct vm_area_struct *vma)
 340 {
 341         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 342                                                       struct class_device,
 343                                                       kobj));
 344
 345         return pci_mmap_legacy_page_range(bus, vma);
 346 }
 347 #endif /* HAVE_PCI_LEGACY */
 348
 349 #ifdef HAVE_PCI_MMAP
 350 /**
 351  * pci_mmap_resource - map a PCI resource into user memory space
 352  * @kobj: kobject for mapping
 353  * @attr: struct bin_attribute for the file being mapped
 354  * @vma: struct vm_area_struct passed into the mmap
 355  *
 356  * Use the regular PCI mapping routines to map a PCI resource into userspace.
 357  * FIXME: write combining?  maybe automatic for prefetchable regions?
 358  */
 359 static int
 360 pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
 361                   struct vm_area_struct *vma)
 362 {
 363         struct pci_dev *pdev = to_pci_dev(container_of(kobj,
 364                                                        struct device, kobj));
 365         struct resource *res = (struct resource *)attr->private;
 366         enum pci_mmap_state mmap_type;
 367         resource_size_t start, end;
 368         int i;
 369
 370         for (i = 0; i < PCI_ROM_RESOURCE; i++)
 371                 if (res == &pdev->resource[i])
 372                         break;
 373         if (i >= PCI_ROM_RESOURCE)
 374                 return -ENODEV;
 375
 376         /* pci_mmap_page_range() expects the same kind of entry as coming
 377          * from /proc/bus/pci/ which is a "user visible" value. If this is
 378          * different from the resource itself, arch will do necessary fixup.
 379          */
 380         pci_resource_to_user(pdev, i, res, &start, &end);
 381         vma->vm_pgoff += start >> PAGE_SHIFT;
 382         mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
 383
 384         return pci_mmap_page_range(pdev, vma, mmap_type, 0);
 385 }
 386
 387 /**
 388  * pci_create_resource_files - create resource files in sysfs for @dev
 389  * @dev: dev in question
 390  *
 391  * Walk the resources in @dev creating files for each resource available.
 392  */
 393 static void
 394 pci_create_resource_files(struct pci_dev *pdev)
 395 {
 396         int i;
 397
 398         /* Expose the PCI resources from this device as files */
 399         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 400                 struct bin_attribute *res_attr;
 401
 402                 /* skip empty resources */
 403                 if (!pci_resource_len(pdev, i))
 404                         continue;
 405
 406                 /* allocate attribute structure, piggyback attribute name */
 407                 res_attr = kzalloc(sizeof(*res_attr) + 10, GFP_ATOMIC);
 408                 if (res_attr) {
 409                         char *res_attr_name = (char *)(res_attr + 1);
 410
 411                         pdev->res_attr[i] = res_attr;
 412                         sprintf(res_attr_name, "resource%d", i);
 413                         res_attr->attr.name = res_attr_name;
 414                         res_attr->attr.mode = S_IRUSR | S_IWUSR;
 415                         res_attr->attr.owner = THIS_MODULE;
 416                         res_attr->size = pci_resource_len(pdev, i);
 417                         res_attr->mmap = pci_mmap_resource;
 418                         res_attr->private = &pdev->resource[i];
 419                         sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
 420                 }
 421         }
 422 }
 423
 424 /**
 425  * pci_remove_resource_files - cleanup resource files
 426  * @dev: dev to cleanup
 427  *
 428  * If we created resource files for @dev, remove them from sysfs and
 429  * free their resources.
 430  */
 431 static void
 432 pci_remove_resource_files(struct pci_dev *pdev)
 433 {
 434         int i;
 435
 436         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 437                 struct bin_attribute *res_attr;
 438
 439                 res_attr = pdev->res_attr[i];
 440                 if (res_attr) {
 441                         sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
 442                         kfree(res_attr);
 443                 }
 444         }
 445 }
 446 #else /* !HAVE_PCI_MMAP */
 447 static inline void pci_create_resource_files(struct pci_dev *dev) { return; }
 448 static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
 449 #endif /* HAVE_PCI_MMAP */
 450
 451 /**
 452  * pci_write_rom - used to enable access to the PCI ROM display
 453  * @kobj: kernel object handle
 454  * @buf: user input
 455  * @off: file offset
 456  * @count: number of byte in input
 457  *
 458  * writing anything except 0 enables it
 459  */
 460 static ssize_t
 461 pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 462 {
 463         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 464
 465         if ((off ==  0) && (*buf == '0') && (count == 2))
 466                 pdev->rom_attr_enabled = 0;
 467         else
 468                 pdev->rom_attr_enabled = 1;
 469
 470         return count;
 471 }
 472
 473 /**
 474  * pci_read_rom - read a PCI ROM
 475  * @kobj: kernel object handle
 476  * @buf: where to put the data we read from the ROM
 477  * @off: file offset
 478  * @count: number of bytes to read
 479  *
 480  * Put @count bytes starting at @off into @buf from the ROM in the PCI
 481  * device corresponding to @kobj.
 482  */
 483 static ssize_t
 484 pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 485 {
 486         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 487         void __iomem *rom;
 488         size_t size;
 489
 490         if (!pdev->rom_attr_enabled)
 491                 return -EINVAL;
 492
 493         rom = pci_map_rom(pdev, &size); /* size starts out as PCI window size */
 494         if (!rom)
 495                 return 0;
 496
 497         if (off >= size)
 498                 count = 0;
 499         else {
 500                 if (off + count > size)
 501                         count = size - off;
 502
 503                 memcpy_fromio(buf, rom + off, count);
 504         }
 505         pci_unmap_rom(pdev, rom);
 506
 507         return count;
 508 }
 509
 510 static struct bin_attribute pci_config_attr = {
 511         .attr = {
 512                 .name = "config",
 513                 .mode = S_IRUGO | S_IWUSR,
 514                 .owner = THIS_MODULE,
 515         },
 516         .size = 256,
 517         .read = pci_read_config,
 518         .write = pci_write_config,
 519 };
 520
 521 static struct bin_attribute pcie_config_attr = {
 522         .attr = {
 523                 .name = "config",
 524                 .mode = S_IRUGO | S_IWUSR,
 525                 .owner = THIS_MODULE,
 526         },
 527         .size = 4096,
 528         .read = pci_read_config,
 529         .write = pci_write_config,
 530 };
 531
 532 int pci_create_sysfs_dev_files (struct pci_dev *pdev)
 533 {
 534         if (!sysfs_initialized)
 535                 return -EACCES;
 536
 537         if (pdev->cfg_size < 4096)
 538                 sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
 539         else
 540                 sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 541
 542         pci_create_resource_files(pdev);
 543
 544         /* If the device has a ROM, try to expose it in sysfs. */
 545         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 546                 struct bin_attribute *rom_attr;
 547
 548                 rom_attr = kzalloc(sizeof(*rom_attr), GFP_ATOMIC);
 549                 if (rom_attr) {
 550                         pdev->rom_attr = rom_attr;
 551                         rom_attr->size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
 552                         rom_attr->attr.name = "rom";
 553                         rom_attr->attr.mode = S_IRUSR;
 554                         rom_attr->attr.owner = THIS_MODULE;
 555                         rom_attr->read = pci_read_rom;
 556                         rom_attr->write = pci_write_rom;
 557                         sysfs_create_bin_file(&pdev->dev.kobj, rom_attr);
 558                 }
 559         }
 560         /* add platform-specific attributes */
 561         pcibios_add_platform_entries(pdev);
 562
 563         return 0;
 564 }
 565
 566 /**
 567  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
 568  * @pdev: device whose entries we should free
 569  *
 570  * Cleanup when @pdev is removed from sysfs.
 571  */
 572 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 573 {
 574         if (pdev->cfg_size < 4096)
 575                 sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
 576         else
 577                 sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 578
 579         pci_remove_resource_files(pdev);
 580
 581         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 582                 if (pdev->rom_attr) {
 583                         sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
 584                         kfree(pdev->rom_attr);
 585                 }
 586         }
 587 }
 588
 589 static int __init pci_sysfs_init(void)
 590 {
 591         struct pci_dev *pdev = NULL;
 592
 593         sysfs_initialized = 1;
 594         for_each_pci_dev(pdev)
 595                 pci_create_sysfs_dev_files(pdev);
 596
 597         return 0;
 598 }
 599
 600 __initcall(pci_sysfs_init);