2 * The PCI Library -- Configuration Access via /sys/bus/pci
4 * Copyright (c) 2003 Matthew Wilcox <matthew@wil.cx>
5 * Copyright (c) 1997--2008 Martin Mares <mj@ucw.cz>
7 * Can be freely distributed and used under the terms of the GNU GPL.
20 #include <sys/types.h>
26 sysfs_config(struct pci_access *a)
28 pci_define_param(a, "sysfs.path", PCI_PATH_SYS_BUS_PCI, "Path to the sysfs device tree");
32 sysfs_name(struct pci_access *a)
34 return pci_get_param(a, "sysfs.path");
38 sysfs_detect(struct pci_access *a)
40 if (access(sysfs_name(a), R_OK))
42 a->debug("...cannot open %s", sysfs_name(a));
45 a->debug("...using %s", sysfs_name(a));
50 sysfs_init(struct pci_access *a)
57 sysfs_flush_cache(struct pci_access *a)
73 sysfs_cleanup(struct pci_access *a)
78 #define OBJNAMELEN 1024
80 sysfs_obj_name(struct pci_dev *d, char *object, char *buf)
82 int n = snprintf(buf, OBJNAMELEN, "%s/devices/%04x:%02x:%02x.%d/%s",
83 sysfs_name(d->access), d->domain, d->bus, d->dev, d->func, object);
84 if (n < 0 || n >= OBJNAMELEN)
85 d->access->error("File name too long");
88 #define OBJBUFSIZE 1024
91 sysfs_get_string(struct pci_dev *d, char *object, char *buf, int mandatory)
93 struct pci_access *a = d->access;
95 char namebuf[OBJNAMELEN];
96 void (*warn)(char *msg, ...) = (mandatory ? a->error : a->warning);
98 sysfs_obj_name(d, object, namebuf);
99 fd = open(namebuf, O_RDONLY);
102 if (mandatory || errno != ENOENT)
103 warn("Cannot open %s: %s", namebuf, strerror(errno));
106 n = read(fd, buf, OBJBUFSIZE);
110 warn("Error reading %s: %s", namebuf, strerror(errno));
115 warn("Value in %s too long", namebuf);
123 sysfs_deref_link(struct pci_dev *d, char *link_name)
125 char path[2*OBJNAMELEN], rel_path[OBJNAMELEN];
127 sysfs_obj_name(d, link_name, path);
128 memset(rel_path, 0, sizeof(rel_path));
130 if (readlink(path, rel_path, sizeof(rel_path)) < 0)
133 sysfs_obj_name(d, "", path);
134 strcat(path, rel_path);
136 // Returns a pointer to malloc'ed memory
137 return realpath(path, NULL);
141 sysfs_get_value(struct pci_dev *d, char *object, int mandatory)
143 char buf[OBJBUFSIZE];
145 if (sysfs_get_string(d, object, buf, mandatory))
146 return strtol(buf, NULL, 0);
152 sysfs_get_resources(struct pci_dev *d)
154 struct pci_access *a = d->access;
155 char namebuf[OBJNAMELEN], buf[256];
159 sysfs_obj_name(d, "resource", namebuf);
160 file = fopen(namebuf, "r");
162 a->error("Cannot open %s: %s", namebuf, strerror(errno));
163 for (i = 0; i < 7; i++)
165 unsigned long long start, end, size, flags;
166 if (!fgets(buf, sizeof(buf), file))
168 if (sscanf(buf, "%llx %llx %llx", &start, &end, &flags) != 3)
169 a->error("Syntax error in %s", namebuf);
171 size = end - start + 1;
177 flags &= PCI_ADDR_FLAG_MASK;
178 d->base_addr[i] = start | flags;
183 d->rom_flags = flags;
184 flags &= PCI_ADDR_FLAG_MASK;
185 d->rom_base_addr = start | flags;
192 static void sysfs_scan(struct pci_access *a)
196 struct dirent *entry;
199 n = snprintf(dirname, sizeof(dirname), "%s/devices", sysfs_name(a));
200 if (n < 0 || n >= (int) sizeof(dirname))
201 a->error("Directory name too long");
202 dir = opendir(dirname);
204 a->error("Cannot open %s", dirname);
205 while ((entry = readdir(dir)))
208 unsigned int dom, bus, dev, func;
210 /* ".", ".." or a special non-device perhaps */
211 if (entry->d_name[0] == '.')
214 d = pci_alloc_dev(a);
215 if (sscanf(entry->d_name, "%x:%x:%x.%d", &dom, &bus, &dev, &func) < 4)
216 a->error("sysfs_scan: Couldn't parse entry name %s", entry->d_name);
218 /* Ensure kernel provided domain that fits in a signed integer */
219 if (dom > 0x7fffffff)
220 a->error("sysfs_scan: Invalid domain %x", dom);
228 sysfs_get_resources(d);
229 d->irq = sysfs_get_value(d, "irq", 1);
231 * We could read these faster from the config registers, but we want to give
232 * the kernel a chance to fix up ID's and especially classes of broken devices.
234 d->vendor_id = sysfs_get_value(d, "vendor", 1);
235 d->device_id = sysfs_get_value(d, "device", 1);
236 d->device_class = sysfs_get_value(d, "class", 1) >> 8;
237 d->known_fields = PCI_FILL_IDENT | PCI_FILL_CLASS | PCI_FILL_IRQ | PCI_FILL_BASES | PCI_FILL_ROM_BASE | PCI_FILL_SIZES | PCI_FILL_IO_FLAGS;
245 sysfs_fill_slots(struct pci_access *a)
249 struct dirent *entry;
252 n = snprintf(dirname, sizeof(dirname), "%s/slots", sysfs_name(a));
253 if (n < 0 || n >= (int) sizeof(dirname))
254 a->error("Directory name too long");
255 dir = opendir(dirname);
259 while (entry = readdir(dir))
261 char namebuf[OBJNAMELEN], buf[16];
263 unsigned int dom, bus, dev;
267 /* ".", ".." or a special non-device perhaps */
268 if (entry->d_name[0] == '.')
271 n = snprintf(namebuf, OBJNAMELEN, "%s/%s/%s", dirname, entry->d_name, "address");
272 if (n < 0 || n >= OBJNAMELEN)
273 a->error("File name too long");
274 file = fopen(namebuf, "r");
276 * Old versions of Linux had a fakephp which didn't have an 'address'
277 * file. There's no useful information to be gleaned from these
278 * devices, pretend they're not there.
283 if (!fgets(buf, sizeof(buf), file) || (res = sscanf(buf, "%x:%x:%x", &dom, &bus, &dev)) < 3)
286 * In some cases, the slot is not tied to a specific device before
287 * a card gets inserted. This happens for example on IBM pSeries
288 * and we need not warn about it.
291 a->warning("sysfs_fill_slots: Couldn't parse entry address %s", buf);
295 for (d = a->devices; d; d = d->next)
296 if (dom == (unsigned)d->domain && bus == d->bus && dev == d->dev && !d->phy_slot)
297 d->phy_slot = pci_set_property(d, PCI_FILL_PHYS_SLOT, entry->d_name);
305 sysfs_fill_info(struct pci_dev *d, int flags)
307 if ((flags & PCI_FILL_PHYS_SLOT) && !(d->known_fields & PCI_FILL_PHYS_SLOT))
310 sysfs_fill_slots(d->access);
311 for (pd = d->access->devices; pd; pd = pd->next)
312 pd->known_fields |= PCI_FILL_PHYS_SLOT;
315 if ((flags & PCI_FILL_MODULE_ALIAS) && !(d->known_fields & PCI_FILL_MODULE_ALIAS))
317 char buf[OBJBUFSIZE];
318 if (sysfs_get_string(d, "modalias", buf, 0))
319 d->module_alias = pci_set_property(d, PCI_FILL_MODULE_ALIAS, buf);
322 if ((flags & PCI_FILL_LABEL) && !(d->known_fields & PCI_FILL_LABEL))
324 char buf[OBJBUFSIZE];
325 if (sysfs_get_string(d, "label", buf, 0))
326 d->label = pci_set_property(d, PCI_FILL_LABEL, buf);
329 if ((flags & PCI_FILL_NUMA_NODE) && !(d->known_fields & PCI_FILL_NUMA_NODE))
330 d->numa_node = sysfs_get_value(d, "numa_node", 0);
332 if ((flags & PCI_FILL_DT_NODE) && !(d->known_fields & PCI_FILL_DT_NODE))
334 char *node = sysfs_deref_link(d, "of_node");
337 pci_set_property(d, PCI_FILL_DT_NODE, node);
342 return pci_generic_fill_info(d, flags);
345 /* Intent of the sysfs_setup() caller */
348 SETUP_READ_CONFIG = 0,
349 SETUP_WRITE_CONFIG = 1,
354 sysfs_setup(struct pci_dev *d, int intent)
356 struct pci_access *a = d->access;
357 char namebuf[OBJNAMELEN];
359 if (a->cached_dev != d || (intent == SETUP_WRITE_CONFIG && !a->fd_rw))
361 sysfs_flush_cache(a);
365 if (intent == SETUP_READ_VPD)
369 sysfs_obj_name(d, "vpd", namebuf);
370 a->fd_vpd = open(namebuf, O_RDONLY);
371 /* No warning on error; vpd may be absent or accessible only to root */
378 sysfs_obj_name(d, "config", namebuf);
379 a->fd_rw = a->writeable || intent == SETUP_WRITE_CONFIG;
380 a->fd = open(namebuf, a->fd_rw ? O_RDWR : O_RDONLY);
382 a->warning("Cannot open %s", namebuf);
388 static int sysfs_read(struct pci_dev *d, int pos, byte *buf, int len)
390 int fd = sysfs_setup(d, SETUP_READ_CONFIG);
395 res = do_read(d, fd, buf, len, pos);
398 d->access->warning("sysfs_read: read failed: %s", strerror(errno));
406 static int sysfs_write(struct pci_dev *d, int pos, byte *buf, int len)
408 int fd = sysfs_setup(d, SETUP_WRITE_CONFIG);
413 res = do_write(d, fd, buf, len, pos);
416 d->access->warning("sysfs_write: write failed: %s", strerror(errno));
421 d->access->warning("sysfs_write: tried to write %d bytes at %d, but only %d succeeded", len, pos, res);
427 #ifdef PCI_HAVE_DO_READ
429 /* pread() is not available and do_read() only works for a single fd, so we
430 * cannot implement read_vpd properly. */
431 static int sysfs_read_vpd(struct pci_dev *d, int pos, byte *buf, int len)
436 #else /* !PCI_HAVE_DO_READ */
438 static int sysfs_read_vpd(struct pci_dev *d, int pos, byte *buf, int len)
440 int fd = sysfs_setup(d, SETUP_READ_VPD);
445 res = pread(fd, buf, len, pos);
448 d->access->warning("sysfs_read_vpd: read failed: %s", strerror(errno));
456 #endif /* PCI_HAVE_DO_READ */
458 static void sysfs_cleanup_dev(struct pci_dev *d)
460 struct pci_access *a = d->access;
462 if (a->cached_dev == d)
463 sysfs_flush_cache(a);
466 struct pci_methods pm_linux_sysfs = {
468 "The sys filesystem on Linux",