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/config.h>
  19 #include <linux/kernel.h>
  20 #include <linux/pci.h>
  21 #include <linux/stat.h>
  22 #include <linux/topology.h>
  23 #include <linux/mm.h>
  24
  25 #include "pci.h"
  26
  27 static int sysfs_initialized;   /* = 0 */
  28
  29 /* show configuration fields */
  30 #define pci_config_attr(field, format_string)                           \
  31 static ssize_t                                                          \
  32 field##_show(struct device *dev, struct device_attribute *attr, char *buf)                              \
  33 {                                                                       \
  34         struct pci_dev *pdev;                                           \
  35                                                                         \
  36         pdev = to_pci_dev (dev);                                        \
  37         return sprintf (buf, format_string, pdev->field);               \
  38 }
  39
  40 pci_config_attr(vendor, "0x%04x\n");
  41 pci_config_attr(device, "0x%04x\n");
  42 pci_config_attr(subsystem_vendor, "0x%04x\n");
  43 pci_config_attr(subsystem_device, "0x%04x\n");
  44 pci_config_attr(class, "0x%06x\n");
  45 pci_config_attr(irq, "%u\n");
  46
  47 static ssize_t local_cpus_show(struct device *dev, struct device_attribute *attr, char *buf)
  48 {
  49         cpumask_t mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
  50         int len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
  51         strcat(buf,"\n");
  52         return 1+len;
  53 }
  54
  55 /* show resources */
  56 static ssize_t
  57 resource_show(struct device * dev, struct device_attribute *attr, char * buf)
  58 {
  59         struct pci_dev * pci_dev = to_pci_dev(dev);
  60         char * str = buf;
  61         int i;
  62         int max = 7;
  63         u64 start, end;
  64
  65         if (pci_dev->subordinate)
  66                 max = DEVICE_COUNT_RESOURCE;
  67
  68         for (i = 0; i < max; i++) {
  69                 struct resource *res =  &pci_dev->resource[i];
  70                 pci_resource_to_user(pci_dev, i, res, &start, &end);
  71                 str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
  72                                (unsigned long long)start,
  73                                (unsigned long long)end,
  74                                (unsigned long long)res->flags);
  75         }
  76         return (str - buf);
  77 }
  78
  79 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
  80 {
  81         struct pci_dev *pci_dev = to_pci_dev(dev);
  82
  83         return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x\n",
  84                        pci_dev->vendor, pci_dev->device,
  85                        pci_dev->subsystem_vendor, pci_dev->subsystem_device,
  86                        (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
  87                        (u8)(pci_dev->class));
  88 }
  89
  90 struct device_attribute pci_dev_attrs[] = {
  91         __ATTR_RO(resource),
  92         __ATTR_RO(vendor),
  93         __ATTR_RO(device),
  94         __ATTR_RO(subsystem_vendor),
  95         __ATTR_RO(subsystem_device),
  96         __ATTR_RO(class),
  97         __ATTR_RO(irq),
  98         __ATTR_RO(local_cpus),
  99         __ATTR_RO(modalias),
 100         __ATTR_NULL,
 101 };
 102
 103 static ssize_t
 104 pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 105 {
 106         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 107         unsigned int size = 64;
 108         loff_t init_off = off;
 109         u8 *data = (u8*) buf;
 110
 111         /* Several chips lock up trying to read undefined config space */
 112         if (capable(CAP_SYS_ADMIN)) {
 113                 size = dev->cfg_size;
 114         } else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 115                 size = 128;
 116         }
 117
 118         if (off > size)
 119                 return 0;
 120         if (off + count > size) {
 121                 size -= off;
 122                 count = size;
 123         } else {
 124                 size = count;
 125         }
 126
 127         if ((off & 1) && size) {
 128                 u8 val;
 129                 pci_read_config_byte(dev, off, &val);
 130                 data[off - init_off] = val;
 131                 off++;
 132                 size--;
 133         }
 134
 135         if ((off & 3) && size > 2) {
 136                 u16 val;
 137                 pci_read_config_word(dev, off, &val);
 138                 data[off - init_off] = val & 0xff;
 139                 data[off - init_off + 1] = (val >> 8) & 0xff;
 140                 off += 2;
 141                 size -= 2;
 142         }
 143
 144         while (size > 3) {
 145                 u32 val;
 146                 pci_read_config_dword(dev, off, &val);
 147                 data[off - init_off] = val & 0xff;
 148                 data[off - init_off + 1] = (val >> 8) & 0xff;
 149                 data[off - init_off + 2] = (val >> 16) & 0xff;
 150                 data[off - init_off + 3] = (val >> 24) & 0xff;
 151                 off += 4;
 152                 size -= 4;
 153         }
 154
 155         if (size >= 2) {
 156                 u16 val;
 157                 pci_read_config_word(dev, off, &val);
 158                 data[off - init_off] = val & 0xff;
 159                 data[off - init_off + 1] = (val >> 8) & 0xff;
 160                 off += 2;
 161                 size -= 2;
 162         }
 163
 164         if (size > 0) {
 165                 u8 val;
 166                 pci_read_config_byte(dev, off, &val);
 167                 data[off - init_off] = val;
 168                 off++;
 169                 --size;
 170         }
 171
 172         return count;
 173 }
 174
 175 static ssize_t
 176 pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 177 {
 178         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 179         unsigned int size = count;
 180         loff_t init_off = off;
 181         u8 *data = (u8*) buf;
 182
 183         if (off > dev->cfg_size)
 184                 return 0;
 185         if (off + count > dev->cfg_size) {
 186                 size = dev->cfg_size - off;
 187                 count = size;
 188         }
 189
 190         if ((off & 1) && size) {
 191                 pci_write_config_byte(dev, off, data[off - init_off]);
 192                 off++;
 193                 size--;
 194         }
 195
 196         if ((off & 3) && size > 2) {
 197                 u16 val = data[off - init_off];
 198                 val |= (u16) data[off - init_off + 1] << 8;
 199                 pci_write_config_word(dev, off, val);
 200                 off += 2;
 201                 size -= 2;
 202         }
 203
 204         while (size > 3) {
 205                 u32 val = data[off - init_off];
 206                 val |= (u32) data[off - init_off + 1] << 8;
 207                 val |= (u32) data[off - init_off + 2] << 16;
 208                 val |= (u32) data[off - init_off + 3] << 24;
 209                 pci_write_config_dword(dev, off, val);
 210                 off += 4;
 211                 size -= 4;
 212         }
 213
 214         if (size >= 2) {
 215                 u16 val = data[off - init_off];
 216                 val |= (u16) data[off - init_off + 1] << 8;
 217                 pci_write_config_word(dev, off, val);
 218                 off += 2;
 219                 size -= 2;
 220         }
 221
 222         if (size) {
 223                 pci_write_config_byte(dev, off, data[off - init_off]);
 224                 off++;
 225                 --size;
 226         }
 227
 228         return count;
 229 }
 230
 231 #ifdef HAVE_PCI_LEGACY
 232 /**
 233  * pci_read_legacy_io - read byte(s) from legacy I/O port space
 234  * @kobj: kobject corresponding to file to read from
 235  * @buf: buffer to store results
 236  * @off: offset into legacy I/O port space
 237  * @count: number of bytes to read
 238  *
 239  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 240  * callback routine (pci_legacy_read).
 241  */
 242 ssize_t
 243 pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 244 {
 245         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 246                                                       struct class_device,
 247                                                       kobj));
 248
 249         /* Only support 1, 2 or 4 byte accesses */
 250         if (count != 1 && count != 2 && count != 4)
 251                 return -EINVAL;
 252
 253         return pci_legacy_read(bus, off, (u32 *)buf, count);
 254 }
 255
 256 /**
 257  * pci_write_legacy_io - write byte(s) to legacy I/O port space
 258  * @kobj: kobject corresponding to file to read from
 259  * @buf: buffer containing value to be written
 260  * @off: offset into legacy I/O port space
 261  * @count: number of bytes to write
 262  *
 263  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 264  * callback routine (pci_legacy_write).
 265  */
 266 ssize_t
 267 pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 268 {
 269         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 270                                                       struct class_device,
 271                                                       kobj));
 272         /* Only support 1, 2 or 4 byte accesses */
 273         if (count != 1 && count != 2 && count != 4)
 274                 return -EINVAL;
 275
 276         return pci_legacy_write(bus, off, *(u32 *)buf, count);
 277 }
 278
 279 /**
 280  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
 281  * @kobj: kobject corresponding to device to be mapped
 282  * @attr: struct bin_attribute for this file
 283  * @vma: struct vm_area_struct passed to mmap
 284  *
 285  * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap
 286  * legacy memory space (first meg of bus space) into application virtual
 287  * memory space.
 288  */
 289 int
 290 pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
 291                     struct vm_area_struct *vma)
 292 {
 293         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 294                                                       struct class_device,
 295                                                       kobj));
 296
 297         return pci_mmap_legacy_page_range(bus, vma);
 298 }
 299 #endif /* HAVE_PCI_LEGACY */
 300
 301 #ifdef HAVE_PCI_MMAP
 302 /**
 303  * pci_mmap_resource - map a PCI resource into user memory space
 304  * @kobj: kobject for mapping
 305  * @attr: struct bin_attribute for the file being mapped
 306  * @vma: struct vm_area_struct passed into the mmap
 307  *
 308  * Use the regular PCI mapping routines to map a PCI resource into userspace.
 309  * FIXME: write combining?  maybe automatic for prefetchable regions?
 310  */
 311 static int
 312 pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
 313                   struct vm_area_struct *vma)
 314 {
 315         struct pci_dev *pdev = to_pci_dev(container_of(kobj,
 316                                                        struct device, kobj));
 317         struct resource *res = (struct resource *)attr->private;
 318         enum pci_mmap_state mmap_type;
 319         u64 start, end;
 320         int i;
 321
 322         for (i = 0; i < PCI_ROM_RESOURCE; i++)
 323                 if (res == &pdev->resource[i])
 324                         break;
 325         if (i >= PCI_ROM_RESOURCE)
 326                 return -ENODEV;
 327
 328         /* pci_mmap_page_range() expects the same kind of entry as coming
 329          * from /proc/bus/pci/ which is a "user visible" value. If this is
 330          * different from the resource itself, arch will do necessary fixup.
 331          */
 332         pci_resource_to_user(pdev, i, res, &start, &end);
 333         vma->vm_pgoff += start >> PAGE_SHIFT;
 334         mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
 335
 336         return pci_mmap_page_range(pdev, vma, mmap_type, 0);
 337 }
 338
 339 /**
 340  * pci_create_resource_files - create resource files in sysfs for @dev
 341  * @dev: dev in question
 342  *
 343  * Walk the resources in @dev creating files for each resource available.
 344  */
 345 static void
 346 pci_create_resource_files(struct pci_dev *pdev)
 347 {
 348         int i;
 349
 350         /* Expose the PCI resources from this device as files */
 351         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 352                 struct bin_attribute *res_attr;
 353
 354                 /* skip empty resources */
 355                 if (!pci_resource_len(pdev, i))
 356                         continue;
 357
 358                 /* allocate attribute structure, piggyback attribute name */
 359                 res_attr = kcalloc(1, sizeof(*res_attr) + 10, GFP_ATOMIC);
 360                 if (res_attr) {
 361                         char *res_attr_name = (char *)(res_attr + 1);
 362
 363                         pdev->res_attr[i] = res_attr;
 364                         sprintf(res_attr_name, "resource%d", i);
 365                         res_attr->attr.name = res_attr_name;
 366                         res_attr->attr.mode = S_IRUSR | S_IWUSR;
 367                         res_attr->attr.owner = THIS_MODULE;
 368                         res_attr->size = pci_resource_len(pdev, i);
 369                         res_attr->mmap = pci_mmap_resource;
 370                         res_attr->private = &pdev->resource[i];
 371                         sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
 372                 }
 373         }
 374 }
 375
 376 /**
 377  * pci_remove_resource_files - cleanup resource files
 378  * @dev: dev to cleanup
 379  *
 380  * If we created resource files for @dev, remove them from sysfs and
 381  * free their resources.
 382  */
 383 static void
 384 pci_remove_resource_files(struct pci_dev *pdev)
 385 {
 386         int i;
 387
 388         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 389                 struct bin_attribute *res_attr;
 390
 391                 res_attr = pdev->res_attr[i];
 392                 if (res_attr) {
 393                         sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
 394                         kfree(res_attr);
 395                 }
 396         }
 397 }
 398 #else /* !HAVE_PCI_MMAP */
 399 static inline void pci_create_resource_files(struct pci_dev *dev) { return; }
 400 static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
 401 #endif /* HAVE_PCI_MMAP */
 402
 403 /**
 404  * pci_write_rom - used to enable access to the PCI ROM display
 405  * @kobj: kernel object handle
 406  * @buf: user input
 407  * @off: file offset
 408  * @count: number of byte in input
 409  *
 410  * writing anything except 0 enables it
 411  */
 412 static ssize_t
 413 pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 414 {
 415         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 416
 417         if ((off ==  0) && (*buf == '0') && (count == 2))
 418                 pdev->rom_attr_enabled = 0;
 419         else
 420                 pdev->rom_attr_enabled = 1;
 421
 422         return count;
 423 }
 424
 425 /**
 426  * pci_read_rom - read a PCI ROM
 427  * @kobj: kernel object handle
 428  * @buf: where to put the data we read from the ROM
 429  * @off: file offset
 430  * @count: number of bytes to read
 431  *
 432  * Put @count bytes starting at @off into @buf from the ROM in the PCI
 433  * device corresponding to @kobj.
 434  */
 435 static ssize_t
 436 pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 437 {
 438         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 439         void __iomem *rom;
 440         size_t size;
 441
 442         if (!pdev->rom_attr_enabled)
 443                 return -EINVAL;
 444
 445         rom = pci_map_rom(pdev, &size); /* size starts out as PCI window size */
 446         if (!rom)
 447                 return 0;
 448
 449         if (off >= size)
 450                 count = 0;
 451         else {
 452                 if (off + count > size)
 453                         count = size - off;
 454
 455                 memcpy_fromio(buf, rom + off, count);
 456         }
 457         pci_unmap_rom(pdev, rom);
 458
 459         return count;
 460 }
 461
 462 static struct bin_attribute pci_config_attr = {
 463         .attr = {
 464                 .name = "config",
 465                 .mode = S_IRUGO | S_IWUSR,
 466                 .owner = THIS_MODULE,
 467         },
 468         .size = 256,
 469         .read = pci_read_config,
 470         .write = pci_write_config,
 471 };
 472
 473 static struct bin_attribute pcie_config_attr = {
 474         .attr = {
 475                 .name = "config",
 476                 .mode = S_IRUGO | S_IWUSR,
 477                 .owner = THIS_MODULE,
 478         },
 479         .size = 4096,
 480         .read = pci_read_config,
 481         .write = pci_write_config,
 482 };
 483
 484 int pci_create_sysfs_dev_files (struct pci_dev *pdev)
 485 {
 486         if (!sysfs_initialized)
 487                 return -EACCES;
 488
 489         if (pdev->cfg_size < 4096)
 490                 sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
 491         else
 492                 sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 493
 494         pci_create_resource_files(pdev);
 495
 496         /* If the device has a ROM, try to expose it in sysfs. */
 497         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 498                 struct bin_attribute *rom_attr;
 499
 500                 rom_attr = kmalloc(sizeof(*rom_attr), GFP_ATOMIC);
 501                 if (rom_attr) {
 502                         memset(rom_attr, 0x00, sizeof(*rom_attr));
 503                         pdev->rom_attr = rom_attr;
 504                         rom_attr->size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
 505                         rom_attr->attr.name = "rom";
 506                         rom_attr->attr.mode = S_IRUSR;
 507                         rom_attr->attr.owner = THIS_MODULE;
 508                         rom_attr->read = pci_read_rom;
 509                         rom_attr->write = pci_write_rom;
 510                         sysfs_create_bin_file(&pdev->dev.kobj, rom_attr);
 511                 }
 512         }
 513         /* add platform-specific attributes */
 514         pcibios_add_platform_entries(pdev);
 515
 516         return 0;
 517 }
 518
 519 /**
 520  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
 521  * @pdev: device whose entries we should free
 522  *
 523  * Cleanup when @pdev is removed from sysfs.
 524  */
 525 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 526 {
 527         if (pdev->cfg_size < 4096)
 528                 sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
 529         else
 530                 sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 531
 532         pci_remove_resource_files(pdev);
 533
 534         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 535                 if (pdev->rom_attr) {
 536                         sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
 537                         kfree(pdev->rom_attr);
 538                 }
 539         }
 540 }
 541
 542 static int __init pci_sysfs_init(void)
 543 {
 544         struct pci_dev *pdev = NULL;
 545
 546         sysfs_initialized = 1;
 547         for_each_pci_dev(pdev)
 548                 pci_create_sysfs_dev_files(pdev);
 549
 550         return 0;
 551 }
 552
 553 __initcall(pci_sysfs_init);