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,
  48                         struct device_attribute *attr, char *buf)
  49 {
  50         cpumask_t mask;
  51         int len;
  52
  53         mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
  54         len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
  55         strcat(buf,"\n");
  56         return 1+len;
  57 }
  58
  59 /* show resources */
  60 static ssize_t
  61 resource_show(struct device * dev, struct device_attribute *attr, char * buf)
  62 {
  63         struct pci_dev * pci_dev = to_pci_dev(dev);
  64         char * str = buf;
  65         int i;
  66         int max = 7;
  67         u64 start, end;
  68
  69         if (pci_dev->subordinate)
  70                 max = DEVICE_COUNT_RESOURCE;
  71
  72         for (i = 0; i < max; i++) {
  73                 struct resource *res =  &pci_dev->resource[i];
  74                 pci_resource_to_user(pci_dev, i, res, &start, &end);
  75                 str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
  76                                (unsigned long long)start,
  77                                (unsigned long long)end,
  78                                (unsigned long long)res->flags);
  79         }
  80         return (str - buf);
  81 }
  82
  83 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
  84 {
  85         struct pci_dev *pci_dev = to_pci_dev(dev);
  86
  87         return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x\n",
  88                        pci_dev->vendor, pci_dev->device,
  89                        pci_dev->subsystem_vendor, pci_dev->subsystem_device,
  90                        (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
  91                        (u8)(pci_dev->class));
  92 }
  93
  94 struct device_attribute pci_dev_attrs[] = {
  95         __ATTR_RO(resource),
  96         __ATTR_RO(vendor),
  97         __ATTR_RO(device),
  98         __ATTR_RO(subsystem_vendor),
  99         __ATTR_RO(subsystem_device),
 100         __ATTR_RO(class),
 101         __ATTR_RO(irq),
 102         __ATTR_RO(local_cpus),
 103         __ATTR_RO(modalias),
 104         __ATTR_NULL,
 105 };
 106
 107 static ssize_t
 108 pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 109 {
 110         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 111         unsigned int size = 64;
 112         loff_t init_off = off;
 113         u8 *data = (u8*) buf;
 114
 115         /* Several chips lock up trying to read undefined config space */
 116         if (capable(CAP_SYS_ADMIN)) {
 117                 size = dev->cfg_size;
 118         } else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 119                 size = 128;
 120         }
 121
 122         if (off > size)
 123                 return 0;
 124         if (off + count > size) {
 125                 size -= off;
 126                 count = size;
 127         } else {
 128                 size = count;
 129         }
 130
 131         if ((off & 1) && size) {
 132                 u8 val;
 133                 pci_read_config_byte(dev, off, &val);
 134                 data[off - init_off] = val;
 135                 off++;
 136                 size--;
 137         }
 138
 139         if ((off & 3) && size > 2) {
 140                 u16 val;
 141                 pci_read_config_word(dev, off, &val);
 142                 data[off - init_off] = val & 0xff;
 143                 data[off - init_off + 1] = (val >> 8) & 0xff;
 144                 off += 2;
 145                 size -= 2;
 146         }
 147
 148         while (size > 3) {
 149                 u32 val;
 150                 pci_read_config_dword(dev, off, &val);
 151                 data[off - init_off] = val & 0xff;
 152                 data[off - init_off + 1] = (val >> 8) & 0xff;
 153                 data[off - init_off + 2] = (val >> 16) & 0xff;
 154                 data[off - init_off + 3] = (val >> 24) & 0xff;
 155                 off += 4;
 156                 size -= 4;
 157         }
 158
 159         if (size >= 2) {
 160                 u16 val;
 161                 pci_read_config_word(dev, off, &val);
 162                 data[off - init_off] = val & 0xff;
 163                 data[off - init_off + 1] = (val >> 8) & 0xff;
 164                 off += 2;
 165                 size -= 2;
 166         }
 167
 168         if (size > 0) {
 169                 u8 val;
 170                 pci_read_config_byte(dev, off, &val);
 171                 data[off - init_off] = val;
 172                 off++;
 173                 --size;
 174         }
 175
 176         return count;
 177 }
 178
 179 static ssize_t
 180 pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 181 {
 182         struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
 183         unsigned int size = count;
 184         loff_t init_off = off;
 185         u8 *data = (u8*) buf;
 186
 187         if (off > dev->cfg_size)
 188                 return 0;
 189         if (off + count > dev->cfg_size) {
 190                 size = dev->cfg_size - off;
 191                 count = size;
 192         }
 193
 194         if ((off & 1) && size) {
 195                 pci_write_config_byte(dev, off, data[off - init_off]);
 196                 off++;
 197                 size--;
 198         }
 199
 200         if ((off & 3) && size > 2) {
 201                 u16 val = data[off - init_off];
 202                 val |= (u16) data[off - init_off + 1] << 8;
 203                 pci_write_config_word(dev, off, val);
 204                 off += 2;
 205                 size -= 2;
 206         }
 207
 208         while (size > 3) {
 209                 u32 val = data[off - init_off];
 210                 val |= (u32) data[off - init_off + 1] << 8;
 211                 val |= (u32) data[off - init_off + 2] << 16;
 212                 val |= (u32) data[off - init_off + 3] << 24;
 213                 pci_write_config_dword(dev, off, val);
 214                 off += 4;
 215                 size -= 4;
 216         }
 217
 218         if (size >= 2) {
 219                 u16 val = data[off - init_off];
 220                 val |= (u16) data[off - init_off + 1] << 8;
 221                 pci_write_config_word(dev, off, val);
 222                 off += 2;
 223                 size -= 2;
 224         }
 225
 226         if (size) {
 227                 pci_write_config_byte(dev, off, data[off - init_off]);
 228                 off++;
 229                 --size;
 230         }
 231
 232         return count;
 233 }
 234
 235 #ifdef HAVE_PCI_LEGACY
 236 /**
 237  * pci_read_legacy_io - read byte(s) from legacy I/O port space
 238  * @kobj: kobject corresponding to file to read from
 239  * @buf: buffer to store results
 240  * @off: offset into legacy I/O port space
 241  * @count: number of bytes to read
 242  *
 243  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 244  * callback routine (pci_legacy_read).
 245  */
 246 ssize_t
 247 pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 248 {
 249         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 250                                                       struct class_device,
 251                                                       kobj));
 252
 253         /* Only support 1, 2 or 4 byte accesses */
 254         if (count != 1 && count != 2 && count != 4)
 255                 return -EINVAL;
 256
 257         return pci_legacy_read(bus, off, (u32 *)buf, count);
 258 }
 259
 260 /**
 261  * pci_write_legacy_io - write byte(s) to legacy I/O port space
 262  * @kobj: kobject corresponding to file to read from
 263  * @buf: buffer containing value to be written
 264  * @off: offset into legacy I/O port space
 265  * @count: number of bytes to write
 266  *
 267  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
 268  * callback routine (pci_legacy_write).
 269  */
 270 ssize_t
 271 pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
 272 {
 273         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 274                                                       struct class_device,
 275                                                       kobj));
 276         /* Only support 1, 2 or 4 byte accesses */
 277         if (count != 1 && count != 2 && count != 4)
 278                 return -EINVAL;
 279
 280         return pci_legacy_write(bus, off, *(u32 *)buf, count);
 281 }
 282
 283 /**
 284  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
 285  * @kobj: kobject corresponding to device to be mapped
 286  * @attr: struct bin_attribute for this file
 287  * @vma: struct vm_area_struct passed to mmap
 288  *
 289  * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap
 290  * legacy memory space (first meg of bus space) into application virtual
 291  * memory space.
 292  */
 293 int
 294 pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
 295                     struct vm_area_struct *vma)
 296 {
 297         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 298                                                       struct class_device,
 299                                                       kobj));
 300
 301         return pci_mmap_legacy_page_range(bus, vma);
 302 }
 303 #endif /* HAVE_PCI_LEGACY */
 304
 305 #ifdef HAVE_PCI_MMAP
 306 /**
 307  * pci_mmap_resource - map a PCI resource into user memory space
 308  * @kobj: kobject for mapping
 309  * @attr: struct bin_attribute for the file being mapped
 310  * @vma: struct vm_area_struct passed into the mmap
 311  *
 312  * Use the regular PCI mapping routines to map a PCI resource into userspace.
 313  * FIXME: write combining?  maybe automatic for prefetchable regions?
 314  */
 315 static int
 316 pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
 317                   struct vm_area_struct *vma)
 318 {
 319         struct pci_dev *pdev = to_pci_dev(container_of(kobj,
 320                                                        struct device, kobj));
 321         struct resource *res = (struct resource *)attr->private;
 322         enum pci_mmap_state mmap_type;
 323         u64 start, end;
 324         int i;
 325
 326         for (i = 0; i < PCI_ROM_RESOURCE; i++)
 327                 if (res == &pdev->resource[i])
 328                         break;
 329         if (i >= PCI_ROM_RESOURCE)
 330                 return -ENODEV;
 331
 332         /* pci_mmap_page_range() expects the same kind of entry as coming
 333          * from /proc/bus/pci/ which is a "user visible" value. If this is
 334          * different from the resource itself, arch will do necessary fixup.
 335          */
 336         pci_resource_to_user(pdev, i, res, &start, &end);
 337         vma->vm_pgoff += start >> PAGE_SHIFT;
 338         mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
 339
 340         return pci_mmap_page_range(pdev, vma, mmap_type, 0);
 341 }
 342
 343 /**
 344  * pci_create_resource_files - create resource files in sysfs for @dev
 345  * @dev: dev in question
 346  *
 347  * Walk the resources in @dev creating files for each resource available.
 348  */
 349 static void
 350 pci_create_resource_files(struct pci_dev *pdev)
 351 {
 352         int i;
 353
 354         /* Expose the PCI resources from this device as files */
 355         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 356                 struct bin_attribute *res_attr;
 357
 358                 /* skip empty resources */
 359                 if (!pci_resource_len(pdev, i))
 360                         continue;
 361
 362                 /* allocate attribute structure, piggyback attribute name */
 363                 res_attr = kzalloc(sizeof(*res_attr) + 10, GFP_ATOMIC);
 364                 if (res_attr) {
 365                         char *res_attr_name = (char *)(res_attr + 1);
 366
 367                         pdev->res_attr[i] = res_attr;
 368                         sprintf(res_attr_name, "resource%d", i);
 369                         res_attr->attr.name = res_attr_name;
 370                         res_attr->attr.mode = S_IRUSR | S_IWUSR;
 371                         res_attr->attr.owner = THIS_MODULE;
 372                         res_attr->size = pci_resource_len(pdev, i);
 373                         res_attr->mmap = pci_mmap_resource;
 374                         res_attr->private = &pdev->resource[i];
 375                         sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
 376                 }
 377         }
 378 }
 379
 380 /**
 381  * pci_remove_resource_files - cleanup resource files
 382  * @dev: dev to cleanup
 383  *
 384  * If we created resource files for @dev, remove them from sysfs and
 385  * free their resources.
 386  */
 387 static void
 388 pci_remove_resource_files(struct pci_dev *pdev)
 389 {
 390         int i;
 391
 392         for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 393                 struct bin_attribute *res_attr;
 394
 395                 res_attr = pdev->res_attr[i];
 396                 if (res_attr) {
 397                         sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
 398                         kfree(res_attr);
 399                 }
 400         }
 401 }
 402 #else /* !HAVE_PCI_MMAP */
 403 static inline void pci_create_resource_files(struct pci_dev *dev) { return; }
 404 static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
 405 #endif /* HAVE_PCI_MMAP */
 406
 407 /**
 408  * pci_write_rom - used to enable access to the PCI ROM display
 409  * @kobj: kernel object handle
 410  * @buf: user input
 411  * @off: file offset
 412  * @count: number of byte in input
 413  *
 414  * writing anything except 0 enables it
 415  */
 416 static ssize_t
 417 pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 418 {
 419         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 420
 421         if ((off ==  0) && (*buf == '0') && (count == 2))
 422                 pdev->rom_attr_enabled = 0;
 423         else
 424                 pdev->rom_attr_enabled = 1;
 425
 426         return count;
 427 }
 428
 429 /**
 430  * pci_read_rom - read a PCI ROM
 431  * @kobj: kernel object handle
 432  * @buf: where to put the data we read from the ROM
 433  * @off: file offset
 434  * @count: number of bytes to read
 435  *
 436  * Put @count bytes starting at @off into @buf from the ROM in the PCI
 437  * device corresponding to @kobj.
 438  */
 439 static ssize_t
 440 pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
 441 {
 442         struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 443         void __iomem *rom;
 444         size_t size;
 445
 446         if (!pdev->rom_attr_enabled)
 447                 return -EINVAL;
 448
 449         rom = pci_map_rom(pdev, &size); /* size starts out as PCI window size */
 450         if (!rom)
 451                 return 0;
 452
 453         if (off >= size)
 454                 count = 0;
 455         else {
 456                 if (off + count > size)
 457                         count = size - off;
 458
 459                 memcpy_fromio(buf, rom + off, count);
 460         }
 461         pci_unmap_rom(pdev, rom);
 462
 463         return count;
 464 }
 465
 466 static struct bin_attribute pci_config_attr = {
 467         .attr = {
 468                 .name = "config",
 469                 .mode = S_IRUGO | S_IWUSR,
 470                 .owner = THIS_MODULE,
 471         },
 472         .size = 256,
 473         .read = pci_read_config,
 474         .write = pci_write_config,
 475 };
 476
 477 static struct bin_attribute pcie_config_attr = {
 478         .attr = {
 479                 .name = "config",
 480                 .mode = S_IRUGO | S_IWUSR,
 481                 .owner = THIS_MODULE,
 482         },
 483         .size = 4096,
 484         .read = pci_read_config,
 485         .write = pci_write_config,
 486 };
 487
 488 int pci_create_sysfs_dev_files (struct pci_dev *pdev)
 489 {
 490         if (!sysfs_initialized)
 491                 return -EACCES;
 492
 493         if (pdev->cfg_size < 4096)
 494                 sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
 495         else
 496                 sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 497
 498         pci_create_resource_files(pdev);
 499
 500         /* If the device has a ROM, try to expose it in sysfs. */
 501         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 502                 struct bin_attribute *rom_attr;
 503
 504                 rom_attr = kmalloc(sizeof(*rom_attr), GFP_ATOMIC);
 505                 if (rom_attr) {
 506                         memset(rom_attr, 0x00, sizeof(*rom_attr));
 507                         pdev->rom_attr = rom_attr;
 508                         rom_attr->size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
 509                         rom_attr->attr.name = "rom";
 510                         rom_attr->attr.mode = S_IRUSR;
 511                         rom_attr->attr.owner = THIS_MODULE;
 512                         rom_attr->read = pci_read_rom;
 513                         rom_attr->write = pci_write_rom;
 514                         sysfs_create_bin_file(&pdev->dev.kobj, rom_attr);
 515                 }
 516         }
 517         /* add platform-specific attributes */
 518         pcibios_add_platform_entries(pdev);
 519
 520         return 0;
 521 }
 522
 523 /**
 524  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
 525  * @pdev: device whose entries we should free
 526  *
 527  * Cleanup when @pdev is removed from sysfs.
 528  */
 529 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 530 {
 531         if (pdev->cfg_size < 4096)
 532                 sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
 533         else
 534                 sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
 535
 536         pci_remove_resource_files(pdev);
 537
 538         if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
 539                 if (pdev->rom_attr) {
 540                         sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
 541                         kfree(pdev->rom_attr);
 542                 }
 543         }
 544 }
 545
 546 static int __init pci_sysfs_init(void)
 547 {
 548         struct pci_dev *pdev = NULL;
 549
 550         sysfs_initialized = 1;
 551         for_each_pci_dev(pdev)
 552                 pci_create_sysfs_dev_files(pdev);
 553
 554         return 0;
 555 }
 556
 557 __initcall(pci_sysfs_init);