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