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