pci.c 126 KB

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  1. /*
  2. * PCI Bus Services, see include/linux/pci.h for further explanation.
  3. *
  4. * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
  5. * David Mosberger-Tang
  6. *
  7. * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
  8. */
  9. #include <linux/kernel.h>
  10. #include <linux/delay.h>
  11. #include <linux/init.h>
  12. #include <linux/of.h>
  13. #include <linux/of_pci.h>
  14. #include <linux/pci.h>
  15. #include <linux/pm.h>
  16. #include <linux/slab.h>
  17. #include <linux/module.h>
  18. #include <linux/spinlock.h>
  19. #include <linux/string.h>
  20. #include <linux/log2.h>
  21. #include <linux/pci-aspm.h>
  22. #include <linux/pm_wakeup.h>
  23. #include <linux/interrupt.h>
  24. #include <linux/device.h>
  25. #include <linux/pm_runtime.h>
  26. #include <linux/pci_hotplug.h>
  27. #include <asm-generic/pci-bridge.h>
  28. #include <asm/setup.h>
  29. #include <linux/aer.h>
  30. #include "pci.h"
  31. const char *pci_power_names[] = {
  32. "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
  33. };
  34. EXPORT_SYMBOL_GPL(pci_power_names);
  35. int isa_dma_bridge_buggy;
  36. EXPORT_SYMBOL(isa_dma_bridge_buggy);
  37. int pci_pci_problems;
  38. EXPORT_SYMBOL(pci_pci_problems);
  39. unsigned int pci_pm_d3_delay;
  40. static void pci_pme_list_scan(struct work_struct *work);
  41. static LIST_HEAD(pci_pme_list);
  42. static DEFINE_MUTEX(pci_pme_list_mutex);
  43. static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
  44. struct pci_pme_device {
  45. struct list_head list;
  46. struct pci_dev *dev;
  47. };
  48. #define PME_TIMEOUT 1000 /* How long between PME checks */
  49. static void pci_dev_d3_sleep(struct pci_dev *dev)
  50. {
  51. unsigned int delay = dev->d3_delay;
  52. if (delay < pci_pm_d3_delay)
  53. delay = pci_pm_d3_delay;
  54. msleep(delay);
  55. }
  56. #ifdef CONFIG_PCI_DOMAINS
  57. int pci_domains_supported = 1;
  58. #endif
  59. #define DEFAULT_CARDBUS_IO_SIZE (256)
  60. #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
  61. /* pci=cbmemsize=nnM,cbiosize=nn can override this */
  62. unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
  63. unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
  64. #define DEFAULT_HOTPLUG_IO_SIZE (256)
  65. #define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
  66. /* pci=hpmemsize=nnM,hpiosize=nn can override this */
  67. unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
  68. unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
  69. enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_DEFAULT;
  70. /*
  71. * The default CLS is used if arch didn't set CLS explicitly and not
  72. * all pci devices agree on the same value. Arch can override either
  73. * the dfl or actual value as it sees fit. Don't forget this is
  74. * measured in 32-bit words, not bytes.
  75. */
  76. u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
  77. u8 pci_cache_line_size;
  78. /*
  79. * If we set up a device for bus mastering, we need to check the latency
  80. * timer as certain BIOSes forget to set it properly.
  81. */
  82. unsigned int pcibios_max_latency = 255;
  83. /* If set, the PCIe ARI capability will not be used. */
  84. static bool pcie_ari_disabled;
  85. /**
  86. * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
  87. * @bus: pointer to PCI bus structure to search
  88. *
  89. * Given a PCI bus, returns the highest PCI bus number present in the set
  90. * including the given PCI bus and its list of child PCI buses.
  91. */
  92. unsigned char pci_bus_max_busnr(struct pci_bus *bus)
  93. {
  94. struct pci_bus *tmp;
  95. unsigned char max, n;
  96. max = bus->busn_res.end;
  97. list_for_each_entry(tmp, &bus->children, node) {
  98. n = pci_bus_max_busnr(tmp);
  99. if (n > max)
  100. max = n;
  101. }
  102. return max;
  103. }
  104. EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
  105. #ifdef CONFIG_HAS_IOMEM
  106. void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
  107. {
  108. struct resource *res = &pdev->resource[bar];
  109. /*
  110. * Make sure the BAR is actually a memory resource, not an IO resource
  111. */
  112. if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) {
  113. dev_warn(&pdev->dev, "can't ioremap BAR %d: %pR\n", bar, res);
  114. return NULL;
  115. }
  116. return ioremap_nocache(res->start, resource_size(res));
  117. }
  118. EXPORT_SYMBOL_GPL(pci_ioremap_bar);
  119. void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
  120. {
  121. /*
  122. * Make sure the BAR is actually a memory resource, not an IO resource
  123. */
  124. if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
  125. WARN_ON(1);
  126. return NULL;
  127. }
  128. return ioremap_wc(pci_resource_start(pdev, bar),
  129. pci_resource_len(pdev, bar));
  130. }
  131. EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
  132. #endif
  133. static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
  134. u8 pos, int cap, int *ttl)
  135. {
  136. u8 id;
  137. u16 ent;
  138. pci_bus_read_config_byte(bus, devfn, pos, &pos);
  139. while ((*ttl)--) {
  140. if (pos < 0x40)
  141. break;
  142. pos &= ~3;
  143. pci_bus_read_config_word(bus, devfn, pos, &ent);
  144. id = ent & 0xff;
  145. if (id == 0xff)
  146. break;
  147. if (id == cap)
  148. return pos;
  149. pos = (ent >> 8);
  150. }
  151. return 0;
  152. }
  153. static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
  154. u8 pos, int cap)
  155. {
  156. int ttl = PCI_FIND_CAP_TTL;
  157. return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
  158. }
  159. int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
  160. {
  161. return __pci_find_next_cap(dev->bus, dev->devfn,
  162. pos + PCI_CAP_LIST_NEXT, cap);
  163. }
  164. EXPORT_SYMBOL_GPL(pci_find_next_capability);
  165. static int __pci_bus_find_cap_start(struct pci_bus *bus,
  166. unsigned int devfn, u8 hdr_type)
  167. {
  168. u16 status;
  169. pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
  170. if (!(status & PCI_STATUS_CAP_LIST))
  171. return 0;
  172. switch (hdr_type) {
  173. case PCI_HEADER_TYPE_NORMAL:
  174. case PCI_HEADER_TYPE_BRIDGE:
  175. return PCI_CAPABILITY_LIST;
  176. case PCI_HEADER_TYPE_CARDBUS:
  177. return PCI_CB_CAPABILITY_LIST;
  178. }
  179. return 0;
  180. }
  181. /**
  182. * pci_find_capability - query for devices' capabilities
  183. * @dev: PCI device to query
  184. * @cap: capability code
  185. *
  186. * Tell if a device supports a given PCI capability.
  187. * Returns the address of the requested capability structure within the
  188. * device's PCI configuration space or 0 in case the device does not
  189. * support it. Possible values for @cap:
  190. *
  191. * %PCI_CAP_ID_PM Power Management
  192. * %PCI_CAP_ID_AGP Accelerated Graphics Port
  193. * %PCI_CAP_ID_VPD Vital Product Data
  194. * %PCI_CAP_ID_SLOTID Slot Identification
  195. * %PCI_CAP_ID_MSI Message Signalled Interrupts
  196. * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
  197. * %PCI_CAP_ID_PCIX PCI-X
  198. * %PCI_CAP_ID_EXP PCI Express
  199. */
  200. int pci_find_capability(struct pci_dev *dev, int cap)
  201. {
  202. int pos;
  203. pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
  204. if (pos)
  205. pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
  206. return pos;
  207. }
  208. EXPORT_SYMBOL(pci_find_capability);
  209. /**
  210. * pci_bus_find_capability - query for devices' capabilities
  211. * @bus: the PCI bus to query
  212. * @devfn: PCI device to query
  213. * @cap: capability code
  214. *
  215. * Like pci_find_capability() but works for pci devices that do not have a
  216. * pci_dev structure set up yet.
  217. *
  218. * Returns the address of the requested capability structure within the
  219. * device's PCI configuration space or 0 in case the device does not
  220. * support it.
  221. */
  222. int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
  223. {
  224. int pos;
  225. u8 hdr_type;
  226. pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
  227. pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
  228. if (pos)
  229. pos = __pci_find_next_cap(bus, devfn, pos, cap);
  230. return pos;
  231. }
  232. EXPORT_SYMBOL(pci_bus_find_capability);
  233. /**
  234. * pci_find_next_ext_capability - Find an extended capability
  235. * @dev: PCI device to query
  236. * @start: address at which to start looking (0 to start at beginning of list)
  237. * @cap: capability code
  238. *
  239. * Returns the address of the next matching extended capability structure
  240. * within the device's PCI configuration space or 0 if the device does
  241. * not support it. Some capabilities can occur several times, e.g., the
  242. * vendor-specific capability, and this provides a way to find them all.
  243. */
  244. int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
  245. {
  246. u32 header;
  247. int ttl;
  248. int pos = PCI_CFG_SPACE_SIZE;
  249. /* minimum 8 bytes per capability */
  250. ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
  251. if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
  252. return 0;
  253. if (start)
  254. pos = start;
  255. if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
  256. return 0;
  257. /*
  258. * If we have no capabilities, this is indicated by cap ID,
  259. * cap version and next pointer all being 0.
  260. */
  261. if (header == 0)
  262. return 0;
  263. while (ttl-- > 0) {
  264. if (PCI_EXT_CAP_ID(header) == cap && pos != start)
  265. return pos;
  266. pos = PCI_EXT_CAP_NEXT(header);
  267. if (pos < PCI_CFG_SPACE_SIZE)
  268. break;
  269. if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
  270. break;
  271. }
  272. return 0;
  273. }
  274. EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
  275. /**
  276. * pci_find_ext_capability - Find an extended capability
  277. * @dev: PCI device to query
  278. * @cap: capability code
  279. *
  280. * Returns the address of the requested extended capability structure
  281. * within the device's PCI configuration space or 0 if the device does
  282. * not support it. Possible values for @cap:
  283. *
  284. * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
  285. * %PCI_EXT_CAP_ID_VC Virtual Channel
  286. * %PCI_EXT_CAP_ID_DSN Device Serial Number
  287. * %PCI_EXT_CAP_ID_PWR Power Budgeting
  288. */
  289. int pci_find_ext_capability(struct pci_dev *dev, int cap)
  290. {
  291. return pci_find_next_ext_capability(dev, 0, cap);
  292. }
  293. EXPORT_SYMBOL_GPL(pci_find_ext_capability);
  294. static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
  295. {
  296. int rc, ttl = PCI_FIND_CAP_TTL;
  297. u8 cap, mask;
  298. if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
  299. mask = HT_3BIT_CAP_MASK;
  300. else
  301. mask = HT_5BIT_CAP_MASK;
  302. pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
  303. PCI_CAP_ID_HT, &ttl);
  304. while (pos) {
  305. rc = pci_read_config_byte(dev, pos + 3, &cap);
  306. if (rc != PCIBIOS_SUCCESSFUL)
  307. return 0;
  308. if ((cap & mask) == ht_cap)
  309. return pos;
  310. pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
  311. pos + PCI_CAP_LIST_NEXT,
  312. PCI_CAP_ID_HT, &ttl);
  313. }
  314. return 0;
  315. }
  316. /**
  317. * pci_find_next_ht_capability - query a device's Hypertransport capabilities
  318. * @dev: PCI device to query
  319. * @pos: Position from which to continue searching
  320. * @ht_cap: Hypertransport capability code
  321. *
  322. * To be used in conjunction with pci_find_ht_capability() to search for
  323. * all capabilities matching @ht_cap. @pos should always be a value returned
  324. * from pci_find_ht_capability().
  325. *
  326. * NB. To be 100% safe against broken PCI devices, the caller should take
  327. * steps to avoid an infinite loop.
  328. */
  329. int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
  330. {
  331. return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
  332. }
  333. EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
  334. /**
  335. * pci_find_ht_capability - query a device's Hypertransport capabilities
  336. * @dev: PCI device to query
  337. * @ht_cap: Hypertransport capability code
  338. *
  339. * Tell if a device supports a given Hypertransport capability.
  340. * Returns an address within the device's PCI configuration space
  341. * or 0 in case the device does not support the request capability.
  342. * The address points to the PCI capability, of type PCI_CAP_ID_HT,
  343. * which has a Hypertransport capability matching @ht_cap.
  344. */
  345. int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
  346. {
  347. int pos;
  348. pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
  349. if (pos)
  350. pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
  351. return pos;
  352. }
  353. EXPORT_SYMBOL_GPL(pci_find_ht_capability);
  354. /**
  355. * pci_find_parent_resource - return resource region of parent bus of given region
  356. * @dev: PCI device structure contains resources to be searched
  357. * @res: child resource record for which parent is sought
  358. *
  359. * For given resource region of given device, return the resource
  360. * region of parent bus the given region is contained in.
  361. */
  362. struct resource *pci_find_parent_resource(const struct pci_dev *dev,
  363. struct resource *res)
  364. {
  365. const struct pci_bus *bus = dev->bus;
  366. struct resource *r;
  367. int i;
  368. pci_bus_for_each_resource(bus, r, i) {
  369. if (!r)
  370. continue;
  371. if (res->start && resource_contains(r, res)) {
  372. /*
  373. * If the window is prefetchable but the BAR is
  374. * not, the allocator made a mistake.
  375. */
  376. if (r->flags & IORESOURCE_PREFETCH &&
  377. !(res->flags & IORESOURCE_PREFETCH))
  378. return NULL;
  379. /*
  380. * If we're below a transparent bridge, there may
  381. * be both a positively-decoded aperture and a
  382. * subtractively-decoded region that contain the BAR.
  383. * We want the positively-decoded one, so this depends
  384. * on pci_bus_for_each_resource() giving us those
  385. * first.
  386. */
  387. return r;
  388. }
  389. }
  390. return NULL;
  391. }
  392. EXPORT_SYMBOL(pci_find_parent_resource);
  393. /**
  394. * pci_find_pcie_root_port - return PCIe Root Port
  395. * @dev: PCI device to query
  396. *
  397. * Traverse up the parent chain and return the PCIe Root Port PCI Device
  398. * for a given PCI Device.
  399. */
  400. struct pci_dev *pci_find_pcie_root_port(struct pci_dev *dev)
  401. {
  402. struct pci_dev *bridge, *highest_pcie_bridge = NULL;
  403. bridge = pci_upstream_bridge(dev);
  404. while (bridge && pci_is_pcie(bridge)) {
  405. highest_pcie_bridge = bridge;
  406. bridge = pci_upstream_bridge(bridge);
  407. }
  408. if (pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
  409. return NULL;
  410. return highest_pcie_bridge;
  411. }
  412. EXPORT_SYMBOL(pci_find_pcie_root_port);
  413. /**
  414. * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
  415. * @dev: the PCI device to operate on
  416. * @pos: config space offset of status word
  417. * @mask: mask of bit(s) to care about in status word
  418. *
  419. * Return 1 when mask bit(s) in status word clear, 0 otherwise.
  420. */
  421. int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
  422. {
  423. int i;
  424. /* Wait for Transaction Pending bit clean */
  425. for (i = 0; i < 4; i++) {
  426. u16 status;
  427. if (i)
  428. msleep((1 << (i - 1)) * 100);
  429. pci_read_config_word(dev, pos, &status);
  430. if (!(status & mask))
  431. return 1;
  432. }
  433. return 0;
  434. }
  435. /**
  436. * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)
  437. * @dev: PCI device to have its BARs restored
  438. *
  439. * Restore the BAR values for a given device, so as to make it
  440. * accessible by its driver.
  441. */
  442. static void pci_restore_bars(struct pci_dev *dev)
  443. {
  444. int i;
  445. for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
  446. pci_update_resource(dev, i);
  447. }
  448. static struct pci_platform_pm_ops *pci_platform_pm;
  449. int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
  450. {
  451. if (!ops->is_manageable || !ops->set_state || !ops->choose_state
  452. || !ops->sleep_wake)
  453. return -EINVAL;
  454. pci_platform_pm = ops;
  455. return 0;
  456. }
  457. static inline bool platform_pci_power_manageable(struct pci_dev *dev)
  458. {
  459. return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
  460. }
  461. static inline int platform_pci_set_power_state(struct pci_dev *dev,
  462. pci_power_t t)
  463. {
  464. return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
  465. }
  466. static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
  467. {
  468. return pci_platform_pm ?
  469. pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
  470. }
  471. static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
  472. {
  473. return pci_platform_pm ?
  474. pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
  475. }
  476. static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
  477. {
  478. return pci_platform_pm ?
  479. pci_platform_pm->run_wake(dev, enable) : -ENODEV;
  480. }
  481. static inline bool platform_pci_need_resume(struct pci_dev *dev)
  482. {
  483. return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
  484. }
  485. /**
  486. * pci_raw_set_power_state - Use PCI PM registers to set the power state of
  487. * given PCI device
  488. * @dev: PCI device to handle.
  489. * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
  490. *
  491. * RETURN VALUE:
  492. * -EINVAL if the requested state is invalid.
  493. * -EIO if device does not support PCI PM or its PM capabilities register has a
  494. * wrong version, or device doesn't support the requested state.
  495. * 0 if device already is in the requested state.
  496. * 0 if device's power state has been successfully changed.
  497. */
  498. static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
  499. {
  500. u16 pmcsr;
  501. bool need_restore = false;
  502. /* Check if we're already there */
  503. if (dev->current_state == state)
  504. return 0;
  505. if (!dev->pm_cap)
  506. return -EIO;
  507. if (state < PCI_D0 || state > PCI_D3hot)
  508. return -EINVAL;
  509. /* Validate current state:
  510. * Can enter D0 from any state, but if we can only go deeper
  511. * to sleep if we're already in a low power state
  512. */
  513. if (state != PCI_D0 && dev->current_state <= PCI_D3cold
  514. && dev->current_state > state) {
  515. dev_err(&dev->dev, "invalid power transition (from state %d to %d)\n",
  516. dev->current_state, state);
  517. return -EINVAL;
  518. }
  519. /* check if this device supports the desired state */
  520. if ((state == PCI_D1 && !dev->d1_support)
  521. || (state == PCI_D2 && !dev->d2_support))
  522. return -EIO;
  523. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
  524. /* If we're (effectively) in D3, force entire word to 0.
  525. * This doesn't affect PME_Status, disables PME_En, and
  526. * sets PowerState to 0.
  527. */
  528. switch (dev->current_state) {
  529. case PCI_D0:
  530. case PCI_D1:
  531. case PCI_D2:
  532. pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
  533. pmcsr |= state;
  534. break;
  535. case PCI_D3hot:
  536. case PCI_D3cold:
  537. case PCI_UNKNOWN: /* Boot-up */
  538. if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
  539. && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
  540. need_restore = true;
  541. /* Fall-through: force to D0 */
  542. default:
  543. pmcsr = 0;
  544. break;
  545. }
  546. /* enter specified state */
  547. pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
  548. /* Mandatory power management transition delays */
  549. /* see PCI PM 1.1 5.6.1 table 18 */
  550. if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
  551. pci_dev_d3_sleep(dev);
  552. else if (state == PCI_D2 || dev->current_state == PCI_D2)
  553. udelay(PCI_PM_D2_DELAY);
  554. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
  555. dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
  556. if (dev->current_state != state && printk_ratelimit())
  557. dev_info(&dev->dev, "Refused to change power state, currently in D%d\n",
  558. dev->current_state);
  559. /*
  560. * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
  561. * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
  562. * from D3hot to D0 _may_ perform an internal reset, thereby
  563. * going to "D0 Uninitialized" rather than "D0 Initialized".
  564. * For example, at least some versions of the 3c905B and the
  565. * 3c556B exhibit this behaviour.
  566. *
  567. * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
  568. * devices in a D3hot state at boot. Consequently, we need to
  569. * restore at least the BARs so that the device will be
  570. * accessible to its driver.
  571. */
  572. if (need_restore)
  573. pci_restore_bars(dev);
  574. if (dev->bus->self)
  575. pcie_aspm_pm_state_change(dev->bus->self);
  576. return 0;
  577. }
  578. /**
  579. * pci_update_current_state - Read PCI power state of given device from its
  580. * PCI PM registers and cache it
  581. * @dev: PCI device to handle.
  582. * @state: State to cache in case the device doesn't have the PM capability
  583. */
  584. void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
  585. {
  586. if (dev->pm_cap) {
  587. u16 pmcsr;
  588. /*
  589. * Configuration space is not accessible for device in
  590. * D3cold, so just keep or set D3cold for safety
  591. */
  592. if (dev->current_state == PCI_D3cold)
  593. return;
  594. if (state == PCI_D3cold) {
  595. dev->current_state = PCI_D3cold;
  596. return;
  597. }
  598. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
  599. dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
  600. } else {
  601. dev->current_state = state;
  602. }
  603. }
  604. /**
  605. * pci_power_up - Put the given device into D0 forcibly
  606. * @dev: PCI device to power up
  607. */
  608. void pci_power_up(struct pci_dev *dev)
  609. {
  610. if (platform_pci_power_manageable(dev))
  611. platform_pci_set_power_state(dev, PCI_D0);
  612. pci_raw_set_power_state(dev, PCI_D0);
  613. pci_update_current_state(dev, PCI_D0);
  614. }
  615. /**
  616. * pci_platform_power_transition - Use platform to change device power state
  617. * @dev: PCI device to handle.
  618. * @state: State to put the device into.
  619. */
  620. static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
  621. {
  622. int error;
  623. if (platform_pci_power_manageable(dev)) {
  624. error = platform_pci_set_power_state(dev, state);
  625. if (!error)
  626. pci_update_current_state(dev, state);
  627. } else
  628. error = -ENODEV;
  629. if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
  630. dev->current_state = PCI_D0;
  631. return error;
  632. }
  633. /**
  634. * pci_wakeup - Wake up a PCI device
  635. * @pci_dev: Device to handle.
  636. * @ign: ignored parameter
  637. */
  638. static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
  639. {
  640. pci_wakeup_event(pci_dev);
  641. pm_request_resume(&pci_dev->dev);
  642. return 0;
  643. }
  644. /**
  645. * pci_wakeup_bus - Walk given bus and wake up devices on it
  646. * @bus: Top bus of the subtree to walk.
  647. */
  648. static void pci_wakeup_bus(struct pci_bus *bus)
  649. {
  650. if (bus)
  651. pci_walk_bus(bus, pci_wakeup, NULL);
  652. }
  653. /**
  654. * __pci_start_power_transition - Start power transition of a PCI device
  655. * @dev: PCI device to handle.
  656. * @state: State to put the device into.
  657. */
  658. static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
  659. {
  660. if (state == PCI_D0) {
  661. pci_platform_power_transition(dev, PCI_D0);
  662. /*
  663. * Mandatory power management transition delays, see
  664. * PCI Express Base Specification Revision 2.0 Section
  665. * 6.6.1: Conventional Reset. Do not delay for
  666. * devices powered on/off by corresponding bridge,
  667. * because have already delayed for the bridge.
  668. */
  669. if (dev->runtime_d3cold) {
  670. msleep(dev->d3cold_delay);
  671. /*
  672. * When powering on a bridge from D3cold, the
  673. * whole hierarchy may be powered on into
  674. * D0uninitialized state, resume them to give
  675. * them a chance to suspend again
  676. */
  677. pci_wakeup_bus(dev->subordinate);
  678. }
  679. }
  680. }
  681. /**
  682. * __pci_dev_set_current_state - Set current state of a PCI device
  683. * @dev: Device to handle
  684. * @data: pointer to state to be set
  685. */
  686. static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
  687. {
  688. pci_power_t state = *(pci_power_t *)data;
  689. dev->current_state = state;
  690. return 0;
  691. }
  692. /**
  693. * __pci_bus_set_current_state - Walk given bus and set current state of devices
  694. * @bus: Top bus of the subtree to walk.
  695. * @state: state to be set
  696. */
  697. static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
  698. {
  699. if (bus)
  700. pci_walk_bus(bus, __pci_dev_set_current_state, &state);
  701. }
  702. /**
  703. * __pci_complete_power_transition - Complete power transition of a PCI device
  704. * @dev: PCI device to handle.
  705. * @state: State to put the device into.
  706. *
  707. * This function should not be called directly by device drivers.
  708. */
  709. int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
  710. {
  711. int ret;
  712. if (state <= PCI_D0)
  713. return -EINVAL;
  714. ret = pci_platform_power_transition(dev, state);
  715. /* Power off the bridge may power off the whole hierarchy */
  716. if (!ret && state == PCI_D3cold)
  717. __pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
  718. return ret;
  719. }
  720. EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
  721. /**
  722. * pci_set_power_state - Set the power state of a PCI device
  723. * @dev: PCI device to handle.
  724. * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
  725. *
  726. * Transition a device to a new power state, using the platform firmware and/or
  727. * the device's PCI PM registers.
  728. *
  729. * RETURN VALUE:
  730. * -EINVAL if the requested state is invalid.
  731. * -EIO if device does not support PCI PM or its PM capabilities register has a
  732. * wrong version, or device doesn't support the requested state.
  733. * 0 if device already is in the requested state.
  734. * 0 if device's power state has been successfully changed.
  735. */
  736. int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
  737. {
  738. int error;
  739. /* bound the state we're entering */
  740. if (state > PCI_D3cold)
  741. state = PCI_D3cold;
  742. else if (state < PCI_D0)
  743. state = PCI_D0;
  744. else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
  745. /*
  746. * If the device or the parent bridge do not support PCI PM,
  747. * ignore the request if we're doing anything other than putting
  748. * it into D0 (which would only happen on boot).
  749. */
  750. return 0;
  751. /* Check if we're already there */
  752. if (dev->current_state == state)
  753. return 0;
  754. __pci_start_power_transition(dev, state);
  755. /* This device is quirked not to be put into D3, so
  756. don't put it in D3 */
  757. if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
  758. return 0;
  759. /*
  760. * To put device in D3cold, we put device into D3hot in native
  761. * way, then put device into D3cold with platform ops
  762. */
  763. error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
  764. PCI_D3hot : state);
  765. if (!__pci_complete_power_transition(dev, state))
  766. error = 0;
  767. return error;
  768. }
  769. EXPORT_SYMBOL(pci_set_power_state);
  770. /**
  771. * pci_choose_state - Choose the power state of a PCI device
  772. * @dev: PCI device to be suspended
  773. * @state: target sleep state for the whole system. This is the value
  774. * that is passed to suspend() function.
  775. *
  776. * Returns PCI power state suitable for given device and given system
  777. * message.
  778. */
  779. pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
  780. {
  781. pci_power_t ret;
  782. if (!dev->pm_cap)
  783. return PCI_D0;
  784. ret = platform_pci_choose_state(dev);
  785. if (ret != PCI_POWER_ERROR)
  786. return ret;
  787. switch (state.event) {
  788. case PM_EVENT_ON:
  789. return PCI_D0;
  790. case PM_EVENT_FREEZE:
  791. case PM_EVENT_PRETHAW:
  792. /* REVISIT both freeze and pre-thaw "should" use D0 */
  793. case PM_EVENT_SUSPEND:
  794. case PM_EVENT_HIBERNATE:
  795. return PCI_D3hot;
  796. default:
  797. dev_info(&dev->dev, "unrecognized suspend event %d\n",
  798. state.event);
  799. BUG();
  800. }
  801. return PCI_D0;
  802. }
  803. EXPORT_SYMBOL(pci_choose_state);
  804. #define PCI_EXP_SAVE_REGS 7
  805. static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
  806. u16 cap, bool extended)
  807. {
  808. struct pci_cap_saved_state *tmp;
  809. hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
  810. if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
  811. return tmp;
  812. }
  813. return NULL;
  814. }
  815. struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
  816. {
  817. return _pci_find_saved_cap(dev, cap, false);
  818. }
  819. struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
  820. {
  821. return _pci_find_saved_cap(dev, cap, true);
  822. }
  823. static int pci_save_pcie_state(struct pci_dev *dev)
  824. {
  825. int i = 0;
  826. struct pci_cap_saved_state *save_state;
  827. u16 *cap;
  828. if (!pci_is_pcie(dev))
  829. return 0;
  830. save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
  831. if (!save_state) {
  832. dev_err(&dev->dev, "buffer not found in %s\n", __func__);
  833. return -ENOMEM;
  834. }
  835. cap = (u16 *)&save_state->cap.data[0];
  836. pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
  837. pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
  838. pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
  839. pcie_capability_read_word(dev, PCI_EXP_RTCTL, &cap[i++]);
  840. pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
  841. pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
  842. pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
  843. return 0;
  844. }
  845. static void pci_restore_pcie_state(struct pci_dev *dev)
  846. {
  847. int i = 0;
  848. struct pci_cap_saved_state *save_state;
  849. u16 *cap;
  850. save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
  851. if (!save_state)
  852. return;
  853. cap = (u16 *)&save_state->cap.data[0];
  854. pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
  855. pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
  856. pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
  857. pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
  858. pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
  859. pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
  860. pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
  861. }
  862. static int pci_save_pcix_state(struct pci_dev *dev)
  863. {
  864. int pos;
  865. struct pci_cap_saved_state *save_state;
  866. pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
  867. if (!pos)
  868. return 0;
  869. save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
  870. if (!save_state) {
  871. dev_err(&dev->dev, "buffer not found in %s\n", __func__);
  872. return -ENOMEM;
  873. }
  874. pci_read_config_word(dev, pos + PCI_X_CMD,
  875. (u16 *)save_state->cap.data);
  876. return 0;
  877. }
  878. static void pci_restore_pcix_state(struct pci_dev *dev)
  879. {
  880. int i = 0, pos;
  881. struct pci_cap_saved_state *save_state;
  882. u16 *cap;
  883. save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
  884. pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
  885. if (!save_state || !pos)
  886. return;
  887. cap = (u16 *)&save_state->cap.data[0];
  888. pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
  889. }
  890. /**
  891. * pci_save_state - save the PCI configuration space of a device before suspending
  892. * @dev: - PCI device that we're dealing with
  893. */
  894. int pci_save_state(struct pci_dev *dev)
  895. {
  896. int i;
  897. /* XXX: 100% dword access ok here? */
  898. for (i = 0; i < 16; i++)
  899. pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
  900. dev->state_saved = true;
  901. i = pci_save_pcie_state(dev);
  902. if (i != 0)
  903. return i;
  904. i = pci_save_pcix_state(dev);
  905. if (i != 0)
  906. return i;
  907. return pci_save_vc_state(dev);
  908. }
  909. EXPORT_SYMBOL(pci_save_state);
  910. static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
  911. u32 saved_val, int retry, bool force)
  912. {
  913. u32 val;
  914. pci_read_config_dword(pdev, offset, &val);
  915. if (!force && val == saved_val)
  916. return;
  917. for (;;) {
  918. dev_dbg(&pdev->dev, "restoring config space at offset %#x (was %#x, writing %#x)\n",
  919. offset, val, saved_val);
  920. pci_write_config_dword(pdev, offset, saved_val);
  921. if (retry-- <= 0)
  922. return;
  923. pci_read_config_dword(pdev, offset, &val);
  924. if (val == saved_val)
  925. return;
  926. mdelay(1);
  927. }
  928. }
  929. static void pci_restore_config_space_range(struct pci_dev *pdev,
  930. int start, int end, int retry,
  931. bool force)
  932. {
  933. int index;
  934. for (index = end; index >= start; index--)
  935. pci_restore_config_dword(pdev, 4 * index,
  936. pdev->saved_config_space[index],
  937. retry, force);
  938. }
  939. static void pci_restore_config_space(struct pci_dev *pdev)
  940. {
  941. if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
  942. pci_restore_config_space_range(pdev, 10, 15, 0, false);
  943. /* Restore BARs before the command register. */
  944. pci_restore_config_space_range(pdev, 4, 9, 10, false);
  945. pci_restore_config_space_range(pdev, 0, 3, 0, false);
  946. } else if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
  947. pci_restore_config_space_range(pdev, 12, 15, 0, false);
  948. /*
  949. * Force rewriting of prefetch registers to avoid S3 resume
  950. * issues on Intel PCI bridges that occur when these
  951. * registers are not explicitly written.
  952. */
  953. pci_restore_config_space_range(pdev, 9, 11, 0, true);
  954. pci_restore_config_space_range(pdev, 0, 8, 0, false);
  955. } else {
  956. pci_restore_config_space_range(pdev, 0, 15, 0, false);
  957. }
  958. }
  959. /**
  960. * pci_restore_state - Restore the saved state of a PCI device
  961. * @dev: - PCI device that we're dealing with
  962. */
  963. void pci_restore_state(struct pci_dev *dev)
  964. {
  965. if (!dev->state_saved)
  966. return;
  967. /* PCI Express register must be restored first */
  968. pci_restore_pcie_state(dev);
  969. pci_restore_ats_state(dev);
  970. pci_restore_vc_state(dev);
  971. pci_cleanup_aer_error_status_regs(dev);
  972. pci_restore_config_space(dev);
  973. pci_restore_pcix_state(dev);
  974. pci_restore_msi_state(dev);
  975. /* Restore ACS and IOV configuration state */
  976. pci_enable_acs(dev);
  977. pci_restore_iov_state(dev);
  978. dev->state_saved = false;
  979. }
  980. EXPORT_SYMBOL(pci_restore_state);
  981. struct pci_saved_state {
  982. u32 config_space[16];
  983. struct pci_cap_saved_data cap[0];
  984. };
  985. /**
  986. * pci_store_saved_state - Allocate and return an opaque struct containing
  987. * the device saved state.
  988. * @dev: PCI device that we're dealing with
  989. *
  990. * Return NULL if no state or error.
  991. */
  992. struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
  993. {
  994. struct pci_saved_state *state;
  995. struct pci_cap_saved_state *tmp;
  996. struct pci_cap_saved_data *cap;
  997. size_t size;
  998. if (!dev->state_saved)
  999. return NULL;
  1000. size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
  1001. hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
  1002. size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
  1003. state = kzalloc(size, GFP_KERNEL);
  1004. if (!state)
  1005. return NULL;
  1006. memcpy(state->config_space, dev->saved_config_space,
  1007. sizeof(state->config_space));
  1008. cap = state->cap;
  1009. hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
  1010. size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
  1011. memcpy(cap, &tmp->cap, len);
  1012. cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
  1013. }
  1014. /* Empty cap_save terminates list */
  1015. return state;
  1016. }
  1017. EXPORT_SYMBOL_GPL(pci_store_saved_state);
  1018. /**
  1019. * pci_load_saved_state - Reload the provided save state into struct pci_dev.
  1020. * @dev: PCI device that we're dealing with
  1021. * @state: Saved state returned from pci_store_saved_state()
  1022. */
  1023. int pci_load_saved_state(struct pci_dev *dev,
  1024. struct pci_saved_state *state)
  1025. {
  1026. struct pci_cap_saved_data *cap;
  1027. dev->state_saved = false;
  1028. if (!state)
  1029. return 0;
  1030. memcpy(dev->saved_config_space, state->config_space,
  1031. sizeof(state->config_space));
  1032. cap = state->cap;
  1033. while (cap->size) {
  1034. struct pci_cap_saved_state *tmp;
  1035. tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
  1036. if (!tmp || tmp->cap.size != cap->size)
  1037. return -EINVAL;
  1038. memcpy(tmp->cap.data, cap->data, tmp->cap.size);
  1039. cap = (struct pci_cap_saved_data *)((u8 *)cap +
  1040. sizeof(struct pci_cap_saved_data) + cap->size);
  1041. }
  1042. dev->state_saved = true;
  1043. return 0;
  1044. }
  1045. EXPORT_SYMBOL_GPL(pci_load_saved_state);
  1046. /**
  1047. * pci_load_and_free_saved_state - Reload the save state pointed to by state,
  1048. * and free the memory allocated for it.
  1049. * @dev: PCI device that we're dealing with
  1050. * @state: Pointer to saved state returned from pci_store_saved_state()
  1051. */
  1052. int pci_load_and_free_saved_state(struct pci_dev *dev,
  1053. struct pci_saved_state **state)
  1054. {
  1055. int ret = pci_load_saved_state(dev, *state);
  1056. kfree(*state);
  1057. *state = NULL;
  1058. return ret;
  1059. }
  1060. EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
  1061. int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
  1062. {
  1063. return pci_enable_resources(dev, bars);
  1064. }
  1065. static int do_pci_enable_device(struct pci_dev *dev, int bars)
  1066. {
  1067. int err;
  1068. struct pci_dev *bridge;
  1069. u16 cmd;
  1070. u8 pin;
  1071. err = pci_set_power_state(dev, PCI_D0);
  1072. if (err < 0 && err != -EIO)
  1073. return err;
  1074. bridge = pci_upstream_bridge(dev);
  1075. if (bridge)
  1076. pcie_aspm_powersave_config_link(bridge);
  1077. err = pcibios_enable_device(dev, bars);
  1078. if (err < 0)
  1079. return err;
  1080. pci_fixup_device(pci_fixup_enable, dev);
  1081. if (dev->msi_enabled || dev->msix_enabled)
  1082. return 0;
  1083. pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
  1084. if (pin) {
  1085. pci_read_config_word(dev, PCI_COMMAND, &cmd);
  1086. if (cmd & PCI_COMMAND_INTX_DISABLE)
  1087. pci_write_config_word(dev, PCI_COMMAND,
  1088. cmd & ~PCI_COMMAND_INTX_DISABLE);
  1089. }
  1090. return 0;
  1091. }
  1092. /**
  1093. * pci_reenable_device - Resume abandoned device
  1094. * @dev: PCI device to be resumed
  1095. *
  1096. * Note this function is a backend of pci_default_resume and is not supposed
  1097. * to be called by normal code, write proper resume handler and use it instead.
  1098. */
  1099. int pci_reenable_device(struct pci_dev *dev)
  1100. {
  1101. if (pci_is_enabled(dev))
  1102. return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
  1103. return 0;
  1104. }
  1105. EXPORT_SYMBOL(pci_reenable_device);
  1106. static void pci_enable_bridge(struct pci_dev *dev)
  1107. {
  1108. struct pci_dev *bridge;
  1109. int retval;
  1110. bridge = pci_upstream_bridge(dev);
  1111. if (bridge)
  1112. pci_enable_bridge(bridge);
  1113. if (pci_is_enabled(dev)) {
  1114. if (!dev->is_busmaster)
  1115. pci_set_master(dev);
  1116. return;
  1117. }
  1118. retval = pci_enable_device(dev);
  1119. if (retval)
  1120. dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n",
  1121. retval);
  1122. pci_set_master(dev);
  1123. }
  1124. static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
  1125. {
  1126. struct pci_dev *bridge;
  1127. int err;
  1128. int i, bars = 0;
  1129. /*
  1130. * Power state could be unknown at this point, either due to a fresh
  1131. * boot or a device removal call. So get the current power state
  1132. * so that things like MSI message writing will behave as expected
  1133. * (e.g. if the device really is in D0 at enable time).
  1134. */
  1135. if (dev->pm_cap) {
  1136. u16 pmcsr;
  1137. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
  1138. dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
  1139. }
  1140. if (atomic_inc_return(&dev->enable_cnt) > 1)
  1141. return 0; /* already enabled */
  1142. bridge = pci_upstream_bridge(dev);
  1143. if (bridge)
  1144. pci_enable_bridge(bridge);
  1145. /* only skip sriov related */
  1146. for (i = 0; i <= PCI_ROM_RESOURCE; i++)
  1147. if (dev->resource[i].flags & flags)
  1148. bars |= (1 << i);
  1149. for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
  1150. if (dev->resource[i].flags & flags)
  1151. bars |= (1 << i);
  1152. err = do_pci_enable_device(dev, bars);
  1153. if (err < 0)
  1154. atomic_dec(&dev->enable_cnt);
  1155. return err;
  1156. }
  1157. /**
  1158. * pci_enable_device_io - Initialize a device for use with IO space
  1159. * @dev: PCI device to be initialized
  1160. *
  1161. * Initialize device before it's used by a driver. Ask low-level code
  1162. * to enable I/O resources. Wake up the device if it was suspended.
  1163. * Beware, this function can fail.
  1164. */
  1165. int pci_enable_device_io(struct pci_dev *dev)
  1166. {
  1167. return pci_enable_device_flags(dev, IORESOURCE_IO);
  1168. }
  1169. EXPORT_SYMBOL(pci_enable_device_io);
  1170. /**
  1171. * pci_enable_device_mem - Initialize a device for use with Memory space
  1172. * @dev: PCI device to be initialized
  1173. *
  1174. * Initialize device before it's used by a driver. Ask low-level code
  1175. * to enable Memory resources. Wake up the device if it was suspended.
  1176. * Beware, this function can fail.
  1177. */
  1178. int pci_enable_device_mem(struct pci_dev *dev)
  1179. {
  1180. return pci_enable_device_flags(dev, IORESOURCE_MEM);
  1181. }
  1182. EXPORT_SYMBOL(pci_enable_device_mem);
  1183. /**
  1184. * pci_enable_device - Initialize device before it's used by a driver.
  1185. * @dev: PCI device to be initialized
  1186. *
  1187. * Initialize device before it's used by a driver. Ask low-level code
  1188. * to enable I/O and memory. Wake up the device if it was suspended.
  1189. * Beware, this function can fail.
  1190. *
  1191. * Note we don't actually enable the device many times if we call
  1192. * this function repeatedly (we just increment the count).
  1193. */
  1194. int pci_enable_device(struct pci_dev *dev)
  1195. {
  1196. return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
  1197. }
  1198. EXPORT_SYMBOL(pci_enable_device);
  1199. /*
  1200. * Managed PCI resources. This manages device on/off, intx/msi/msix
  1201. * on/off and BAR regions. pci_dev itself records msi/msix status, so
  1202. * there's no need to track it separately. pci_devres is initialized
  1203. * when a device is enabled using managed PCI device enable interface.
  1204. */
  1205. struct pci_devres {
  1206. unsigned int enabled:1;
  1207. unsigned int pinned:1;
  1208. unsigned int orig_intx:1;
  1209. unsigned int restore_intx:1;
  1210. u32 region_mask;
  1211. };
  1212. static void pcim_release(struct device *gendev, void *res)
  1213. {
  1214. struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
  1215. struct pci_devres *this = res;
  1216. int i;
  1217. if (dev->msi_enabled)
  1218. pci_disable_msi(dev);
  1219. if (dev->msix_enabled)
  1220. pci_disable_msix(dev);
  1221. for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
  1222. if (this->region_mask & (1 << i))
  1223. pci_release_region(dev, i);
  1224. if (this->restore_intx)
  1225. pci_intx(dev, this->orig_intx);
  1226. if (this->enabled && !this->pinned)
  1227. pci_disable_device(dev);
  1228. }
  1229. static struct pci_devres *get_pci_dr(struct pci_dev *pdev)
  1230. {
  1231. struct pci_devres *dr, *new_dr;
  1232. dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
  1233. if (dr)
  1234. return dr;
  1235. new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
  1236. if (!new_dr)
  1237. return NULL;
  1238. return devres_get(&pdev->dev, new_dr, NULL, NULL);
  1239. }
  1240. static struct pci_devres *find_pci_dr(struct pci_dev *pdev)
  1241. {
  1242. if (pci_is_managed(pdev))
  1243. return devres_find(&pdev->dev, pcim_release, NULL, NULL);
  1244. return NULL;
  1245. }
  1246. /**
  1247. * pcim_enable_device - Managed pci_enable_device()
  1248. * @pdev: PCI device to be initialized
  1249. *
  1250. * Managed pci_enable_device().
  1251. */
  1252. int pcim_enable_device(struct pci_dev *pdev)
  1253. {
  1254. struct pci_devres *dr;
  1255. int rc;
  1256. dr = get_pci_dr(pdev);
  1257. if (unlikely(!dr))
  1258. return -ENOMEM;
  1259. if (dr->enabled)
  1260. return 0;
  1261. rc = pci_enable_device(pdev);
  1262. if (!rc) {
  1263. pdev->is_managed = 1;
  1264. dr->enabled = 1;
  1265. }
  1266. return rc;
  1267. }
  1268. EXPORT_SYMBOL(pcim_enable_device);
  1269. /**
  1270. * pcim_pin_device - Pin managed PCI device
  1271. * @pdev: PCI device to pin
  1272. *
  1273. * Pin managed PCI device @pdev. Pinned device won't be disabled on
  1274. * driver detach. @pdev must have been enabled with
  1275. * pcim_enable_device().
  1276. */
  1277. void pcim_pin_device(struct pci_dev *pdev)
  1278. {
  1279. struct pci_devres *dr;
  1280. dr = find_pci_dr(pdev);
  1281. WARN_ON(!dr || !dr->enabled);
  1282. if (dr)
  1283. dr->pinned = 1;
  1284. }
  1285. EXPORT_SYMBOL(pcim_pin_device);
  1286. /*
  1287. * pcibios_add_device - provide arch specific hooks when adding device dev
  1288. * @dev: the PCI device being added
  1289. *
  1290. * Permits the platform to provide architecture specific functionality when
  1291. * devices are added. This is the default implementation. Architecture
  1292. * implementations can override this.
  1293. */
  1294. int __weak pcibios_add_device(struct pci_dev *dev)
  1295. {
  1296. return 0;
  1297. }
  1298. /**
  1299. * pcibios_release_device - provide arch specific hooks when releasing device dev
  1300. * @dev: the PCI device being released
  1301. *
  1302. * Permits the platform to provide architecture specific functionality when
  1303. * devices are released. This is the default implementation. Architecture
  1304. * implementations can override this.
  1305. */
  1306. void __weak pcibios_release_device(struct pci_dev *dev) {}
  1307. /**
  1308. * pcibios_disable_device - disable arch specific PCI resources for device dev
  1309. * @dev: the PCI device to disable
  1310. *
  1311. * Disables architecture specific PCI resources for the device. This
  1312. * is the default implementation. Architecture implementations can
  1313. * override this.
  1314. */
  1315. void __weak pcibios_disable_device (struct pci_dev *dev) {}
  1316. /**
  1317. * pcibios_penalize_isa_irq - penalize an ISA IRQ
  1318. * @irq: ISA IRQ to penalize
  1319. * @active: IRQ active or not
  1320. *
  1321. * Permits the platform to provide architecture-specific functionality when
  1322. * penalizing ISA IRQs. This is the default implementation. Architecture
  1323. * implementations can override this.
  1324. */
  1325. void __weak pcibios_penalize_isa_irq(int irq, int active) {}
  1326. static void do_pci_disable_device(struct pci_dev *dev)
  1327. {
  1328. u16 pci_command;
  1329. pci_read_config_word(dev, PCI_COMMAND, &pci_command);
  1330. if (pci_command & PCI_COMMAND_MASTER) {
  1331. pci_command &= ~PCI_COMMAND_MASTER;
  1332. pci_write_config_word(dev, PCI_COMMAND, pci_command);
  1333. }
  1334. pcibios_disable_device(dev);
  1335. }
  1336. /**
  1337. * pci_disable_enabled_device - Disable device without updating enable_cnt
  1338. * @dev: PCI device to disable
  1339. *
  1340. * NOTE: This function is a backend of PCI power management routines and is
  1341. * not supposed to be called drivers.
  1342. */
  1343. void pci_disable_enabled_device(struct pci_dev *dev)
  1344. {
  1345. if (pci_is_enabled(dev))
  1346. do_pci_disable_device(dev);
  1347. }
  1348. /**
  1349. * pci_disable_device - Disable PCI device after use
  1350. * @dev: PCI device to be disabled
  1351. *
  1352. * Signal to the system that the PCI device is not in use by the system
  1353. * anymore. This only involves disabling PCI bus-mastering, if active.
  1354. *
  1355. * Note we don't actually disable the device until all callers of
  1356. * pci_enable_device() have called pci_disable_device().
  1357. */
  1358. void pci_disable_device(struct pci_dev *dev)
  1359. {
  1360. struct pci_devres *dr;
  1361. dr = find_pci_dr(dev);
  1362. if (dr)
  1363. dr->enabled = 0;
  1364. dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
  1365. "disabling already-disabled device");
  1366. if (atomic_dec_return(&dev->enable_cnt) != 0)
  1367. return;
  1368. do_pci_disable_device(dev);
  1369. dev->is_busmaster = 0;
  1370. }
  1371. EXPORT_SYMBOL(pci_disable_device);
  1372. /**
  1373. * pcibios_set_pcie_reset_state - set reset state for device dev
  1374. * @dev: the PCIe device reset
  1375. * @state: Reset state to enter into
  1376. *
  1377. *
  1378. * Sets the PCIe reset state for the device. This is the default
  1379. * implementation. Architecture implementations can override this.
  1380. */
  1381. int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
  1382. enum pcie_reset_state state)
  1383. {
  1384. return -EINVAL;
  1385. }
  1386. /**
  1387. * pci_set_pcie_reset_state - set reset state for device dev
  1388. * @dev: the PCIe device reset
  1389. * @state: Reset state to enter into
  1390. *
  1391. *
  1392. * Sets the PCI reset state for the device.
  1393. */
  1394. int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
  1395. {
  1396. return pcibios_set_pcie_reset_state(dev, state);
  1397. }
  1398. EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
  1399. /**
  1400. * pci_check_pme_status - Check if given device has generated PME.
  1401. * @dev: Device to check.
  1402. *
  1403. * Check the PME status of the device and if set, clear it and clear PME enable
  1404. * (if set). Return 'true' if PME status and PME enable were both set or
  1405. * 'false' otherwise.
  1406. */
  1407. bool pci_check_pme_status(struct pci_dev *dev)
  1408. {
  1409. int pmcsr_pos;
  1410. u16 pmcsr;
  1411. bool ret = false;
  1412. if (!dev->pm_cap)
  1413. return false;
  1414. pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
  1415. pci_read_config_word(dev, pmcsr_pos, &pmcsr);
  1416. if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
  1417. return false;
  1418. /* Clear PME status. */
  1419. pmcsr |= PCI_PM_CTRL_PME_STATUS;
  1420. if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
  1421. /* Disable PME to avoid interrupt flood. */
  1422. pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
  1423. ret = true;
  1424. }
  1425. pci_write_config_word(dev, pmcsr_pos, pmcsr);
  1426. return ret;
  1427. }
  1428. /**
  1429. * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
  1430. * @dev: Device to handle.
  1431. * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
  1432. *
  1433. * Check if @dev has generated PME and queue a resume request for it in that
  1434. * case.
  1435. */
  1436. static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
  1437. {
  1438. if (pme_poll_reset && dev->pme_poll)
  1439. dev->pme_poll = false;
  1440. if (pci_check_pme_status(dev)) {
  1441. pci_wakeup_event(dev);
  1442. pm_request_resume(&dev->dev);
  1443. }
  1444. return 0;
  1445. }
  1446. /**
  1447. * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
  1448. * @bus: Top bus of the subtree to walk.
  1449. */
  1450. void pci_pme_wakeup_bus(struct pci_bus *bus)
  1451. {
  1452. if (bus)
  1453. pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
  1454. }
  1455. /**
  1456. * pci_pme_capable - check the capability of PCI device to generate PME#
  1457. * @dev: PCI device to handle.
  1458. * @state: PCI state from which device will issue PME#.
  1459. */
  1460. bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
  1461. {
  1462. if (!dev->pm_cap)
  1463. return false;
  1464. return !!(dev->pme_support & (1 << state));
  1465. }
  1466. EXPORT_SYMBOL(pci_pme_capable);
  1467. static void pci_pme_list_scan(struct work_struct *work)
  1468. {
  1469. struct pci_pme_device *pme_dev, *n;
  1470. mutex_lock(&pci_pme_list_mutex);
  1471. list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
  1472. if (pme_dev->dev->pme_poll) {
  1473. struct pci_dev *bridge;
  1474. bridge = pme_dev->dev->bus->self;
  1475. /*
  1476. * If bridge is in low power state, the
  1477. * configuration space of subordinate devices
  1478. * may be not accessible
  1479. */
  1480. if (bridge && bridge->current_state != PCI_D0)
  1481. continue;
  1482. pci_pme_wakeup(pme_dev->dev, NULL);
  1483. } else {
  1484. list_del(&pme_dev->list);
  1485. kfree(pme_dev);
  1486. }
  1487. }
  1488. if (!list_empty(&pci_pme_list))
  1489. queue_delayed_work(system_freezable_wq, &pci_pme_work,
  1490. msecs_to_jiffies(PME_TIMEOUT));
  1491. mutex_unlock(&pci_pme_list_mutex);
  1492. }
  1493. static void __pci_pme_active(struct pci_dev *dev, bool enable)
  1494. {
  1495. u16 pmcsr;
  1496. if (!dev->pme_support)
  1497. return;
  1498. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
  1499. /* Clear PME_Status by writing 1 to it and enable PME# */
  1500. pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
  1501. if (!enable)
  1502. pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
  1503. pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
  1504. }
  1505. /**
  1506. * pci_pme_active - enable or disable PCI device's PME# function
  1507. * @dev: PCI device to handle.
  1508. * @enable: 'true' to enable PME# generation; 'false' to disable it.
  1509. *
  1510. * The caller must verify that the device is capable of generating PME# before
  1511. * calling this function with @enable equal to 'true'.
  1512. */
  1513. void pci_pme_active(struct pci_dev *dev, bool enable)
  1514. {
  1515. __pci_pme_active(dev, enable);
  1516. /*
  1517. * PCI (as opposed to PCIe) PME requires that the device have
  1518. * its PME# line hooked up correctly. Not all hardware vendors
  1519. * do this, so the PME never gets delivered and the device
  1520. * remains asleep. The easiest way around this is to
  1521. * periodically walk the list of suspended devices and check
  1522. * whether any have their PME flag set. The assumption is that
  1523. * we'll wake up often enough anyway that this won't be a huge
  1524. * hit, and the power savings from the devices will still be a
  1525. * win.
  1526. *
  1527. * Although PCIe uses in-band PME message instead of PME# line
  1528. * to report PME, PME does not work for some PCIe devices in
  1529. * reality. For example, there are devices that set their PME
  1530. * status bits, but don't really bother to send a PME message;
  1531. * there are PCI Express Root Ports that don't bother to
  1532. * trigger interrupts when they receive PME messages from the
  1533. * devices below. So PME poll is used for PCIe devices too.
  1534. */
  1535. if (dev->pme_poll) {
  1536. struct pci_pme_device *pme_dev;
  1537. if (enable) {
  1538. pme_dev = kmalloc(sizeof(struct pci_pme_device),
  1539. GFP_KERNEL);
  1540. if (!pme_dev) {
  1541. dev_warn(&dev->dev, "can't enable PME#\n");
  1542. return;
  1543. }
  1544. pme_dev->dev = dev;
  1545. mutex_lock(&pci_pme_list_mutex);
  1546. list_add(&pme_dev->list, &pci_pme_list);
  1547. if (list_is_singular(&pci_pme_list))
  1548. queue_delayed_work(system_freezable_wq,
  1549. &pci_pme_work,
  1550. msecs_to_jiffies(PME_TIMEOUT));
  1551. mutex_unlock(&pci_pme_list_mutex);
  1552. } else {
  1553. mutex_lock(&pci_pme_list_mutex);
  1554. list_for_each_entry(pme_dev, &pci_pme_list, list) {
  1555. if (pme_dev->dev == dev) {
  1556. list_del(&pme_dev->list);
  1557. kfree(pme_dev);
  1558. break;
  1559. }
  1560. }
  1561. mutex_unlock(&pci_pme_list_mutex);
  1562. }
  1563. }
  1564. dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled");
  1565. }
  1566. EXPORT_SYMBOL(pci_pme_active);
  1567. /**
  1568. * __pci_enable_wake - enable PCI device as wakeup event source
  1569. * @dev: PCI device affected
  1570. * @state: PCI state from which device will issue wakeup events
  1571. * @runtime: True if the events are to be generated at run time
  1572. * @enable: True to enable event generation; false to disable
  1573. *
  1574. * This enables the device as a wakeup event source, or disables it.
  1575. * When such events involves platform-specific hooks, those hooks are
  1576. * called automatically by this routine.
  1577. *
  1578. * Devices with legacy power management (no standard PCI PM capabilities)
  1579. * always require such platform hooks.
  1580. *
  1581. * RETURN VALUE:
  1582. * 0 is returned on success
  1583. * -EINVAL is returned if device is not supposed to wake up the system
  1584. * Error code depending on the platform is returned if both the platform and
  1585. * the native mechanism fail to enable the generation of wake-up events
  1586. */
  1587. int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
  1588. bool runtime, bool enable)
  1589. {
  1590. int ret = 0;
  1591. if (enable && !runtime && !device_may_wakeup(&dev->dev))
  1592. return -EINVAL;
  1593. /* Don't do the same thing twice in a row for one device. */
  1594. if (!!enable == !!dev->wakeup_prepared)
  1595. return 0;
  1596. /*
  1597. * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
  1598. * Anderson we should be doing PME# wake enable followed by ACPI wake
  1599. * enable. To disable wake-up we call the platform first, for symmetry.
  1600. */
  1601. if (enable) {
  1602. int error;
  1603. if (pci_pme_capable(dev, state))
  1604. pci_pme_active(dev, true);
  1605. else
  1606. ret = 1;
  1607. error = runtime ? platform_pci_run_wake(dev, true) :
  1608. platform_pci_sleep_wake(dev, true);
  1609. if (ret)
  1610. ret = error;
  1611. if (!ret)
  1612. dev->wakeup_prepared = true;
  1613. } else {
  1614. if (runtime)
  1615. platform_pci_run_wake(dev, false);
  1616. else
  1617. platform_pci_sleep_wake(dev, false);
  1618. pci_pme_active(dev, false);
  1619. dev->wakeup_prepared = false;
  1620. }
  1621. return ret;
  1622. }
  1623. EXPORT_SYMBOL(__pci_enable_wake);
  1624. /**
  1625. * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
  1626. * @dev: PCI device to prepare
  1627. * @enable: True to enable wake-up event generation; false to disable
  1628. *
  1629. * Many drivers want the device to wake up the system from D3_hot or D3_cold
  1630. * and this function allows them to set that up cleanly - pci_enable_wake()
  1631. * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
  1632. * ordering constraints.
  1633. *
  1634. * This function only returns error code if the device is not capable of
  1635. * generating PME# from both D3_hot and D3_cold, and the platform is unable to
  1636. * enable wake-up power for it.
  1637. */
  1638. int pci_wake_from_d3(struct pci_dev *dev, bool enable)
  1639. {
  1640. return pci_pme_capable(dev, PCI_D3cold) ?
  1641. pci_enable_wake(dev, PCI_D3cold, enable) :
  1642. pci_enable_wake(dev, PCI_D3hot, enable);
  1643. }
  1644. EXPORT_SYMBOL(pci_wake_from_d3);
  1645. /**
  1646. * pci_target_state - find an appropriate low power state for a given PCI dev
  1647. * @dev: PCI device
  1648. *
  1649. * Use underlying platform code to find a supported low power state for @dev.
  1650. * If the platform can't manage @dev, return the deepest state from which it
  1651. * can generate wake events, based on any available PME info.
  1652. */
  1653. static pci_power_t pci_target_state(struct pci_dev *dev)
  1654. {
  1655. pci_power_t target_state = PCI_D3hot;
  1656. if (platform_pci_power_manageable(dev)) {
  1657. /*
  1658. * Call the platform to choose the target state of the device
  1659. * and enable wake-up from this state if supported.
  1660. */
  1661. pci_power_t state = platform_pci_choose_state(dev);
  1662. switch (state) {
  1663. case PCI_POWER_ERROR:
  1664. case PCI_UNKNOWN:
  1665. break;
  1666. case PCI_D1:
  1667. case PCI_D2:
  1668. if (pci_no_d1d2(dev))
  1669. break;
  1670. default:
  1671. target_state = state;
  1672. }
  1673. } else if (!dev->pm_cap) {
  1674. target_state = PCI_D0;
  1675. } else if (device_may_wakeup(&dev->dev)) {
  1676. /*
  1677. * Find the deepest state from which the device can generate
  1678. * wake-up events, make it the target state and enable device
  1679. * to generate PME#.
  1680. */
  1681. if (dev->pme_support) {
  1682. while (target_state
  1683. && !(dev->pme_support & (1 << target_state)))
  1684. target_state--;
  1685. }
  1686. }
  1687. return target_state;
  1688. }
  1689. /**
  1690. * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
  1691. * @dev: Device to handle.
  1692. *
  1693. * Choose the power state appropriate for the device depending on whether
  1694. * it can wake up the system and/or is power manageable by the platform
  1695. * (PCI_D3hot is the default) and put the device into that state.
  1696. */
  1697. int pci_prepare_to_sleep(struct pci_dev *dev)
  1698. {
  1699. pci_power_t target_state = pci_target_state(dev);
  1700. int error;
  1701. if (target_state == PCI_POWER_ERROR)
  1702. return -EIO;
  1703. pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
  1704. error = pci_set_power_state(dev, target_state);
  1705. if (error)
  1706. pci_enable_wake(dev, target_state, false);
  1707. return error;
  1708. }
  1709. EXPORT_SYMBOL(pci_prepare_to_sleep);
  1710. /**
  1711. * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
  1712. * @dev: Device to handle.
  1713. *
  1714. * Disable device's system wake-up capability and put it into D0.
  1715. */
  1716. int pci_back_from_sleep(struct pci_dev *dev)
  1717. {
  1718. pci_enable_wake(dev, PCI_D0, false);
  1719. return pci_set_power_state(dev, PCI_D0);
  1720. }
  1721. EXPORT_SYMBOL(pci_back_from_sleep);
  1722. /**
  1723. * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
  1724. * @dev: PCI device being suspended.
  1725. *
  1726. * Prepare @dev to generate wake-up events at run time and put it into a low
  1727. * power state.
  1728. */
  1729. int pci_finish_runtime_suspend(struct pci_dev *dev)
  1730. {
  1731. pci_power_t target_state = pci_target_state(dev);
  1732. int error;
  1733. if (target_state == PCI_POWER_ERROR)
  1734. return -EIO;
  1735. dev->runtime_d3cold = target_state == PCI_D3cold;
  1736. __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
  1737. error = pci_set_power_state(dev, target_state);
  1738. if (error) {
  1739. __pci_enable_wake(dev, target_state, true, false);
  1740. dev->runtime_d3cold = false;
  1741. }
  1742. return error;
  1743. }
  1744. /**
  1745. * pci_dev_run_wake - Check if device can generate run-time wake-up events.
  1746. * @dev: Device to check.
  1747. *
  1748. * Return true if the device itself is capable of generating wake-up events
  1749. * (through the platform or using the native PCIe PME) or if the device supports
  1750. * PME and one of its upstream bridges can generate wake-up events.
  1751. */
  1752. bool pci_dev_run_wake(struct pci_dev *dev)
  1753. {
  1754. struct pci_bus *bus = dev->bus;
  1755. if (device_run_wake(&dev->dev))
  1756. return true;
  1757. if (!dev->pme_support)
  1758. return false;
  1759. /* PME-capable in principle, but not from the intended sleep state */
  1760. if (!pci_pme_capable(dev, pci_target_state(dev)))
  1761. return false;
  1762. while (bus->parent) {
  1763. struct pci_dev *bridge = bus->self;
  1764. if (device_run_wake(&bridge->dev))
  1765. return true;
  1766. bus = bus->parent;
  1767. }
  1768. /* We have reached the root bus. */
  1769. if (bus->bridge)
  1770. return device_run_wake(bus->bridge);
  1771. return false;
  1772. }
  1773. EXPORT_SYMBOL_GPL(pci_dev_run_wake);
  1774. /**
  1775. * pci_dev_keep_suspended - Check if the device can stay in the suspended state.
  1776. * @pci_dev: Device to check.
  1777. *
  1778. * Return 'true' if the device is runtime-suspended, it doesn't have to be
  1779. * reconfigured due to wakeup settings difference between system and runtime
  1780. * suspend and the current power state of it is suitable for the upcoming
  1781. * (system) transition.
  1782. *
  1783. * If the device is not configured for system wakeup, disable PME for it before
  1784. * returning 'true' to prevent it from waking up the system unnecessarily.
  1785. */
  1786. bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
  1787. {
  1788. struct device *dev = &pci_dev->dev;
  1789. if (!pm_runtime_suspended(dev)
  1790. || pci_target_state(pci_dev) != pci_dev->current_state
  1791. || platform_pci_need_resume(pci_dev))
  1792. return false;
  1793. /*
  1794. * At this point the device is good to go unless it's been configured
  1795. * to generate PME at the runtime suspend time, but it is not supposed
  1796. * to wake up the system. In that case, simply disable PME for it
  1797. * (it will have to be re-enabled on exit from system resume).
  1798. *
  1799. * If the device's power state is D3cold and the platform check above
  1800. * hasn't triggered, the device's configuration is suitable and we don't
  1801. * need to manipulate it at all.
  1802. */
  1803. spin_lock_irq(&dev->power.lock);
  1804. if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold &&
  1805. !device_may_wakeup(dev))
  1806. __pci_pme_active(pci_dev, false);
  1807. spin_unlock_irq(&dev->power.lock);
  1808. return true;
  1809. }
  1810. /**
  1811. * pci_dev_complete_resume - Finalize resume from system sleep for a device.
  1812. * @pci_dev: Device to handle.
  1813. *
  1814. * If the device is runtime suspended and wakeup-capable, enable PME for it as
  1815. * it might have been disabled during the prepare phase of system suspend if
  1816. * the device was not configured for system wakeup.
  1817. */
  1818. void pci_dev_complete_resume(struct pci_dev *pci_dev)
  1819. {
  1820. struct device *dev = &pci_dev->dev;
  1821. if (!pci_dev_run_wake(pci_dev))
  1822. return;
  1823. spin_lock_irq(&dev->power.lock);
  1824. if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold)
  1825. __pci_pme_active(pci_dev, true);
  1826. spin_unlock_irq(&dev->power.lock);
  1827. }
  1828. void pci_config_pm_runtime_get(struct pci_dev *pdev)
  1829. {
  1830. struct device *dev = &pdev->dev;
  1831. struct device *parent = dev->parent;
  1832. if (parent)
  1833. pm_runtime_get_sync(parent);
  1834. pm_runtime_get_noresume(dev);
  1835. /*
  1836. * pdev->current_state is set to PCI_D3cold during suspending,
  1837. * so wait until suspending completes
  1838. */
  1839. pm_runtime_barrier(dev);
  1840. /*
  1841. * Only need to resume devices in D3cold, because config
  1842. * registers are still accessible for devices suspended but
  1843. * not in D3cold.
  1844. */
  1845. if (pdev->current_state == PCI_D3cold)
  1846. pm_runtime_resume(dev);
  1847. }
  1848. void pci_config_pm_runtime_put(struct pci_dev *pdev)
  1849. {
  1850. struct device *dev = &pdev->dev;
  1851. struct device *parent = dev->parent;
  1852. pm_runtime_put(dev);
  1853. if (parent)
  1854. pm_runtime_put_sync(parent);
  1855. }
  1856. /**
  1857. * pci_pm_init - Initialize PM functions of given PCI device
  1858. * @dev: PCI device to handle.
  1859. */
  1860. void pci_pm_init(struct pci_dev *dev)
  1861. {
  1862. int pm;
  1863. u16 pmc;
  1864. pm_runtime_forbid(&dev->dev);
  1865. pm_runtime_set_active(&dev->dev);
  1866. pm_runtime_enable(&dev->dev);
  1867. device_enable_async_suspend(&dev->dev);
  1868. dev->wakeup_prepared = false;
  1869. dev->pm_cap = 0;
  1870. dev->pme_support = 0;
  1871. /* find PCI PM capability in list */
  1872. pm = pci_find_capability(dev, PCI_CAP_ID_PM);
  1873. if (!pm)
  1874. return;
  1875. /* Check device's ability to generate PME# */
  1876. pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
  1877. if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
  1878. dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
  1879. pmc & PCI_PM_CAP_VER_MASK);
  1880. return;
  1881. }
  1882. dev->pm_cap = pm;
  1883. dev->d3_delay = PCI_PM_D3_WAIT;
  1884. dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
  1885. dev->d3cold_allowed = true;
  1886. dev->d1_support = false;
  1887. dev->d2_support = false;
  1888. if (!pci_no_d1d2(dev)) {
  1889. if (pmc & PCI_PM_CAP_D1)
  1890. dev->d1_support = true;
  1891. if (pmc & PCI_PM_CAP_D2)
  1892. dev->d2_support = true;
  1893. if (dev->d1_support || dev->d2_support)
  1894. dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
  1895. dev->d1_support ? " D1" : "",
  1896. dev->d2_support ? " D2" : "");
  1897. }
  1898. pmc &= PCI_PM_CAP_PME_MASK;
  1899. if (pmc) {
  1900. dev_printk(KERN_DEBUG, &dev->dev,
  1901. "PME# supported from%s%s%s%s%s\n",
  1902. (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
  1903. (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
  1904. (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
  1905. (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
  1906. (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
  1907. dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
  1908. dev->pme_poll = true;
  1909. /*
  1910. * Make device's PM flags reflect the wake-up capability, but
  1911. * let the user space enable it to wake up the system as needed.
  1912. */
  1913. device_set_wakeup_capable(&dev->dev, true);
  1914. /* Disable the PME# generation functionality */
  1915. pci_pme_active(dev, false);
  1916. }
  1917. }
  1918. static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)
  1919. {
  1920. unsigned long flags = IORESOURCE_PCI_FIXED;
  1921. switch (prop) {
  1922. case PCI_EA_P_MEM:
  1923. case PCI_EA_P_VF_MEM:
  1924. flags |= IORESOURCE_MEM;
  1925. break;
  1926. case PCI_EA_P_MEM_PREFETCH:
  1927. case PCI_EA_P_VF_MEM_PREFETCH:
  1928. flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
  1929. break;
  1930. case PCI_EA_P_IO:
  1931. flags |= IORESOURCE_IO;
  1932. break;
  1933. default:
  1934. return 0;
  1935. }
  1936. return flags;
  1937. }
  1938. static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei,
  1939. u8 prop)
  1940. {
  1941. if (bei <= PCI_EA_BEI_BAR5 && prop <= PCI_EA_P_IO)
  1942. return &dev->resource[bei];
  1943. #ifdef CONFIG_PCI_IOV
  1944. else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5 &&
  1945. (prop == PCI_EA_P_VF_MEM || prop == PCI_EA_P_VF_MEM_PREFETCH))
  1946. return &dev->resource[PCI_IOV_RESOURCES +
  1947. bei - PCI_EA_BEI_VF_BAR0];
  1948. #endif
  1949. else if (bei == PCI_EA_BEI_ROM)
  1950. return &dev->resource[PCI_ROM_RESOURCE];
  1951. else
  1952. return NULL;
  1953. }
  1954. /* Read an Enhanced Allocation (EA) entry */
  1955. static int pci_ea_read(struct pci_dev *dev, int offset)
  1956. {
  1957. struct resource *res;
  1958. int ent_size, ent_offset = offset;
  1959. resource_size_t start, end;
  1960. unsigned long flags;
  1961. u32 dw0, bei, base, max_offset;
  1962. u8 prop;
  1963. bool support_64 = (sizeof(resource_size_t) >= 8);
  1964. pci_read_config_dword(dev, ent_offset, &dw0);
  1965. ent_offset += 4;
  1966. /* Entry size field indicates DWORDs after 1st */
  1967. ent_size = ((dw0 & PCI_EA_ES) + 1) << 2;
  1968. if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
  1969. goto out;
  1970. bei = (dw0 & PCI_EA_BEI) >> 4;
  1971. prop = (dw0 & PCI_EA_PP) >> 8;
  1972. /*
  1973. * If the Property is in the reserved range, try the Secondary
  1974. * Property instead.
  1975. */
  1976. if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
  1977. prop = (dw0 & PCI_EA_SP) >> 16;
  1978. if (prop > PCI_EA_P_BRIDGE_IO)
  1979. goto out;
  1980. res = pci_ea_get_resource(dev, bei, prop);
  1981. if (!res) {
  1982. dev_err(&dev->dev, "Unsupported EA entry BEI: %u\n", bei);
  1983. goto out;
  1984. }
  1985. flags = pci_ea_flags(dev, prop);
  1986. if (!flags) {
  1987. dev_err(&dev->dev, "Unsupported EA properties: %#x\n", prop);
  1988. goto out;
  1989. }
  1990. /* Read Base */
  1991. pci_read_config_dword(dev, ent_offset, &base);
  1992. start = (base & PCI_EA_FIELD_MASK);
  1993. ent_offset += 4;
  1994. /* Read MaxOffset */
  1995. pci_read_config_dword(dev, ent_offset, &max_offset);
  1996. ent_offset += 4;
  1997. /* Read Base MSBs (if 64-bit entry) */
  1998. if (base & PCI_EA_IS_64) {
  1999. u32 base_upper;
  2000. pci_read_config_dword(dev, ent_offset, &base_upper);
  2001. ent_offset += 4;
  2002. flags |= IORESOURCE_MEM_64;
  2003. /* entry starts above 32-bit boundary, can't use */
  2004. if (!support_64 && base_upper)
  2005. goto out;
  2006. if (support_64)
  2007. start |= ((u64)base_upper << 32);
  2008. }
  2009. end = start + (max_offset | 0x03);
  2010. /* Read MaxOffset MSBs (if 64-bit entry) */
  2011. if (max_offset & PCI_EA_IS_64) {
  2012. u32 max_offset_upper;
  2013. pci_read_config_dword(dev, ent_offset, &max_offset_upper);
  2014. ent_offset += 4;
  2015. flags |= IORESOURCE_MEM_64;
  2016. /* entry too big, can't use */
  2017. if (!support_64 && max_offset_upper)
  2018. goto out;
  2019. if (support_64)
  2020. end += ((u64)max_offset_upper << 32);
  2021. }
  2022. if (end < start) {
  2023. dev_err(&dev->dev, "EA Entry crosses address boundary\n");
  2024. goto out;
  2025. }
  2026. if (ent_size != ent_offset - offset) {
  2027. dev_err(&dev->dev,
  2028. "EA Entry Size (%d) does not match length read (%d)\n",
  2029. ent_size, ent_offset - offset);
  2030. goto out;
  2031. }
  2032. res->name = pci_name(dev);
  2033. res->start = start;
  2034. res->end = end;
  2035. res->flags = flags;
  2036. if (bei <= PCI_EA_BEI_BAR5)
  2037. dev_printk(KERN_DEBUG, &dev->dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
  2038. bei, res, prop);
  2039. else if (bei == PCI_EA_BEI_ROM)
  2040. dev_printk(KERN_DEBUG, &dev->dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
  2041. res, prop);
  2042. else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
  2043. dev_printk(KERN_DEBUG, &dev->dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
  2044. bei - PCI_EA_BEI_VF_BAR0, res, prop);
  2045. else
  2046. dev_printk(KERN_DEBUG, &dev->dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
  2047. bei, res, prop);
  2048. out:
  2049. return offset + ent_size;
  2050. }
  2051. /* Enhanced Allocation Initalization */
  2052. void pci_ea_init(struct pci_dev *dev)
  2053. {
  2054. int ea;
  2055. u8 num_ent;
  2056. int offset;
  2057. int i;
  2058. /* find PCI EA capability in list */
  2059. ea = pci_find_capability(dev, PCI_CAP_ID_EA);
  2060. if (!ea)
  2061. return;
  2062. /* determine the number of entries */
  2063. pci_bus_read_config_byte(dev->bus, dev->devfn, ea + PCI_EA_NUM_ENT,
  2064. &num_ent);
  2065. num_ent &= PCI_EA_NUM_ENT_MASK;
  2066. offset = ea + PCI_EA_FIRST_ENT;
  2067. /* Skip DWORD 2 for type 1 functions */
  2068. if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
  2069. offset += 4;
  2070. /* parse each EA entry */
  2071. for (i = 0; i < num_ent; ++i)
  2072. offset = pci_ea_read(dev, offset);
  2073. }
  2074. static void pci_add_saved_cap(struct pci_dev *pci_dev,
  2075. struct pci_cap_saved_state *new_cap)
  2076. {
  2077. hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
  2078. }
  2079. /**
  2080. * _pci_add_cap_save_buffer - allocate buffer for saving given
  2081. * capability registers
  2082. * @dev: the PCI device
  2083. * @cap: the capability to allocate the buffer for
  2084. * @extended: Standard or Extended capability ID
  2085. * @size: requested size of the buffer
  2086. */
  2087. static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
  2088. bool extended, unsigned int size)
  2089. {
  2090. int pos;
  2091. struct pci_cap_saved_state *save_state;
  2092. if (extended)
  2093. pos = pci_find_ext_capability(dev, cap);
  2094. else
  2095. pos = pci_find_capability(dev, cap);
  2096. if (!pos)
  2097. return 0;
  2098. save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
  2099. if (!save_state)
  2100. return -ENOMEM;
  2101. save_state->cap.cap_nr = cap;
  2102. save_state->cap.cap_extended = extended;
  2103. save_state->cap.size = size;
  2104. pci_add_saved_cap(dev, save_state);
  2105. return 0;
  2106. }
  2107. int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
  2108. {
  2109. return _pci_add_cap_save_buffer(dev, cap, false, size);
  2110. }
  2111. int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
  2112. {
  2113. return _pci_add_cap_save_buffer(dev, cap, true, size);
  2114. }
  2115. /**
  2116. * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
  2117. * @dev: the PCI device
  2118. */
  2119. void pci_allocate_cap_save_buffers(struct pci_dev *dev)
  2120. {
  2121. int error;
  2122. error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
  2123. PCI_EXP_SAVE_REGS * sizeof(u16));
  2124. if (error)
  2125. dev_err(&dev->dev,
  2126. "unable to preallocate PCI Express save buffer\n");
  2127. error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
  2128. if (error)
  2129. dev_err(&dev->dev,
  2130. "unable to preallocate PCI-X save buffer\n");
  2131. pci_allocate_vc_save_buffers(dev);
  2132. }
  2133. void pci_free_cap_save_buffers(struct pci_dev *dev)
  2134. {
  2135. struct pci_cap_saved_state *tmp;
  2136. struct hlist_node *n;
  2137. hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
  2138. kfree(tmp);
  2139. }
  2140. /**
  2141. * pci_configure_ari - enable or disable ARI forwarding
  2142. * @dev: the PCI device
  2143. *
  2144. * If @dev and its upstream bridge both support ARI, enable ARI in the
  2145. * bridge. Otherwise, disable ARI in the bridge.
  2146. */
  2147. void pci_configure_ari(struct pci_dev *dev)
  2148. {
  2149. u32 cap;
  2150. struct pci_dev *bridge;
  2151. if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
  2152. return;
  2153. bridge = dev->bus->self;
  2154. if (!bridge)
  2155. return;
  2156. pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
  2157. if (!(cap & PCI_EXP_DEVCAP2_ARI))
  2158. return;
  2159. if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
  2160. pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
  2161. PCI_EXP_DEVCTL2_ARI);
  2162. bridge->ari_enabled = 1;
  2163. } else {
  2164. pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
  2165. PCI_EXP_DEVCTL2_ARI);
  2166. bridge->ari_enabled = 0;
  2167. }
  2168. }
  2169. static int pci_acs_enable;
  2170. /**
  2171. * pci_request_acs - ask for ACS to be enabled if supported
  2172. */
  2173. void pci_request_acs(void)
  2174. {
  2175. pci_acs_enable = 1;
  2176. }
  2177. /**
  2178. * pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
  2179. * @dev: the PCI device
  2180. */
  2181. static int pci_std_enable_acs(struct pci_dev *dev)
  2182. {
  2183. int pos;
  2184. u16 cap;
  2185. u16 ctrl;
  2186. pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
  2187. if (!pos)
  2188. return -ENODEV;
  2189. pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
  2190. pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
  2191. /* Source Validation */
  2192. ctrl |= (cap & PCI_ACS_SV);
  2193. /* P2P Request Redirect */
  2194. ctrl |= (cap & PCI_ACS_RR);
  2195. /* P2P Completion Redirect */
  2196. ctrl |= (cap & PCI_ACS_CR);
  2197. /* Upstream Forwarding */
  2198. ctrl |= (cap & PCI_ACS_UF);
  2199. pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
  2200. return 0;
  2201. }
  2202. /**
  2203. * pci_enable_acs - enable ACS if hardware support it
  2204. * @dev: the PCI device
  2205. */
  2206. void pci_enable_acs(struct pci_dev *dev)
  2207. {
  2208. if (!pci_acs_enable)
  2209. return;
  2210. if (!pci_std_enable_acs(dev))
  2211. return;
  2212. pci_dev_specific_enable_acs(dev);
  2213. }
  2214. static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
  2215. {
  2216. int pos;
  2217. u16 cap, ctrl;
  2218. pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
  2219. if (!pos)
  2220. return false;
  2221. /*
  2222. * Except for egress control, capabilities are either required
  2223. * or only required if controllable. Features missing from the
  2224. * capability field can therefore be assumed as hard-wired enabled.
  2225. */
  2226. pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
  2227. acs_flags &= (cap | PCI_ACS_EC);
  2228. pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
  2229. return (ctrl & acs_flags) == acs_flags;
  2230. }
  2231. /**
  2232. * pci_acs_enabled - test ACS against required flags for a given device
  2233. * @pdev: device to test
  2234. * @acs_flags: required PCI ACS flags
  2235. *
  2236. * Return true if the device supports the provided flags. Automatically
  2237. * filters out flags that are not implemented on multifunction devices.
  2238. *
  2239. * Note that this interface checks the effective ACS capabilities of the
  2240. * device rather than the actual capabilities. For instance, most single
  2241. * function endpoints are not required to support ACS because they have no
  2242. * opportunity for peer-to-peer access. We therefore return 'true'
  2243. * regardless of whether the device exposes an ACS capability. This makes
  2244. * it much easier for callers of this function to ignore the actual type
  2245. * or topology of the device when testing ACS support.
  2246. */
  2247. bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
  2248. {
  2249. int ret;
  2250. ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
  2251. if (ret >= 0)
  2252. return ret > 0;
  2253. /*
  2254. * Conventional PCI and PCI-X devices never support ACS, either
  2255. * effectively or actually. The shared bus topology implies that
  2256. * any device on the bus can receive or snoop DMA.
  2257. */
  2258. if (!pci_is_pcie(pdev))
  2259. return false;
  2260. switch (pci_pcie_type(pdev)) {
  2261. /*
  2262. * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
  2263. * but since their primary interface is PCI/X, we conservatively
  2264. * handle them as we would a non-PCIe device.
  2265. */
  2266. case PCI_EXP_TYPE_PCIE_BRIDGE:
  2267. /*
  2268. * PCIe 3.0, 6.12.1 excludes ACS on these devices. "ACS is never
  2269. * applicable... must never implement an ACS Extended Capability...".
  2270. * This seems arbitrary, but we take a conservative interpretation
  2271. * of this statement.
  2272. */
  2273. case PCI_EXP_TYPE_PCI_BRIDGE:
  2274. case PCI_EXP_TYPE_RC_EC:
  2275. return false;
  2276. /*
  2277. * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
  2278. * implement ACS in order to indicate their peer-to-peer capabilities,
  2279. * regardless of whether they are single- or multi-function devices.
  2280. */
  2281. case PCI_EXP_TYPE_DOWNSTREAM:
  2282. case PCI_EXP_TYPE_ROOT_PORT:
  2283. return pci_acs_flags_enabled(pdev, acs_flags);
  2284. /*
  2285. * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
  2286. * implemented by the remaining PCIe types to indicate peer-to-peer
  2287. * capabilities, but only when they are part of a multifunction
  2288. * device. The footnote for section 6.12 indicates the specific
  2289. * PCIe types included here.
  2290. */
  2291. case PCI_EXP_TYPE_ENDPOINT:
  2292. case PCI_EXP_TYPE_UPSTREAM:
  2293. case PCI_EXP_TYPE_LEG_END:
  2294. case PCI_EXP_TYPE_RC_END:
  2295. if (!pdev->multifunction)
  2296. break;
  2297. return pci_acs_flags_enabled(pdev, acs_flags);
  2298. }
  2299. /*
  2300. * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
  2301. * to single function devices with the exception of downstream ports.
  2302. */
  2303. return true;
  2304. }
  2305. /**
  2306. * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
  2307. * @start: starting downstream device
  2308. * @end: ending upstream device or NULL to search to the root bus
  2309. * @acs_flags: required flags
  2310. *
  2311. * Walk up a device tree from start to end testing PCI ACS support. If
  2312. * any step along the way does not support the required flags, return false.
  2313. */
  2314. bool pci_acs_path_enabled(struct pci_dev *start,
  2315. struct pci_dev *end, u16 acs_flags)
  2316. {
  2317. struct pci_dev *pdev, *parent = start;
  2318. do {
  2319. pdev = parent;
  2320. if (!pci_acs_enabled(pdev, acs_flags))
  2321. return false;
  2322. if (pci_is_root_bus(pdev->bus))
  2323. return (end == NULL);
  2324. parent = pdev->bus->self;
  2325. } while (pdev != end);
  2326. return true;
  2327. }
  2328. /**
  2329. * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
  2330. * @dev: the PCI device
  2331. * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
  2332. *
  2333. * Perform INTx swizzling for a device behind one level of bridge. This is
  2334. * required by section 9.1 of the PCI-to-PCI bridge specification for devices
  2335. * behind bridges on add-in cards. For devices with ARI enabled, the slot
  2336. * number is always 0 (see the Implementation Note in section 2.2.8.1 of
  2337. * the PCI Express Base Specification, Revision 2.1)
  2338. */
  2339. u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
  2340. {
  2341. int slot;
  2342. if (pci_ari_enabled(dev->bus))
  2343. slot = 0;
  2344. else
  2345. slot = PCI_SLOT(dev->devfn);
  2346. return (((pin - 1) + slot) % 4) + 1;
  2347. }
  2348. int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
  2349. {
  2350. u8 pin;
  2351. pin = dev->pin;
  2352. if (!pin)
  2353. return -1;
  2354. while (!pci_is_root_bus(dev->bus)) {
  2355. pin = pci_swizzle_interrupt_pin(dev, pin);
  2356. dev = dev->bus->self;
  2357. }
  2358. *bridge = dev;
  2359. return pin;
  2360. }
  2361. /**
  2362. * pci_common_swizzle - swizzle INTx all the way to root bridge
  2363. * @dev: the PCI device
  2364. * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
  2365. *
  2366. * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
  2367. * bridges all the way up to a PCI root bus.
  2368. */
  2369. u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
  2370. {
  2371. u8 pin = *pinp;
  2372. while (!pci_is_root_bus(dev->bus)) {
  2373. pin = pci_swizzle_interrupt_pin(dev, pin);
  2374. dev = dev->bus->self;
  2375. }
  2376. *pinp = pin;
  2377. return PCI_SLOT(dev->devfn);
  2378. }
  2379. EXPORT_SYMBOL_GPL(pci_common_swizzle);
  2380. /**
  2381. * pci_release_region - Release a PCI bar
  2382. * @pdev: PCI device whose resources were previously reserved by pci_request_region
  2383. * @bar: BAR to release
  2384. *
  2385. * Releases the PCI I/O and memory resources previously reserved by a
  2386. * successful call to pci_request_region. Call this function only
  2387. * after all use of the PCI regions has ceased.
  2388. */
  2389. void pci_release_region(struct pci_dev *pdev, int bar)
  2390. {
  2391. struct pci_devres *dr;
  2392. if (pci_resource_len(pdev, bar) == 0)
  2393. return;
  2394. if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
  2395. release_region(pci_resource_start(pdev, bar),
  2396. pci_resource_len(pdev, bar));
  2397. else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
  2398. release_mem_region(pci_resource_start(pdev, bar),
  2399. pci_resource_len(pdev, bar));
  2400. dr = find_pci_dr(pdev);
  2401. if (dr)
  2402. dr->region_mask &= ~(1 << bar);
  2403. }
  2404. EXPORT_SYMBOL(pci_release_region);
  2405. /**
  2406. * __pci_request_region - Reserved PCI I/O and memory resource
  2407. * @pdev: PCI device whose resources are to be reserved
  2408. * @bar: BAR to be reserved
  2409. * @res_name: Name to be associated with resource.
  2410. * @exclusive: whether the region access is exclusive or not
  2411. *
  2412. * Mark the PCI region associated with PCI device @pdev BR @bar as
  2413. * being reserved by owner @res_name. Do not access any
  2414. * address inside the PCI regions unless this call returns
  2415. * successfully.
  2416. *
  2417. * If @exclusive is set, then the region is marked so that userspace
  2418. * is explicitly not allowed to map the resource via /dev/mem or
  2419. * sysfs MMIO access.
  2420. *
  2421. * Returns 0 on success, or %EBUSY on error. A warning
  2422. * message is also printed on failure.
  2423. */
  2424. static int __pci_request_region(struct pci_dev *pdev, int bar,
  2425. const char *res_name, int exclusive)
  2426. {
  2427. struct pci_devres *dr;
  2428. if (pci_resource_len(pdev, bar) == 0)
  2429. return 0;
  2430. if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
  2431. if (!request_region(pci_resource_start(pdev, bar),
  2432. pci_resource_len(pdev, bar), res_name))
  2433. goto err_out;
  2434. } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
  2435. if (!__request_mem_region(pci_resource_start(pdev, bar),
  2436. pci_resource_len(pdev, bar), res_name,
  2437. exclusive))
  2438. goto err_out;
  2439. }
  2440. dr = find_pci_dr(pdev);
  2441. if (dr)
  2442. dr->region_mask |= 1 << bar;
  2443. return 0;
  2444. err_out:
  2445. dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
  2446. &pdev->resource[bar]);
  2447. return -EBUSY;
  2448. }
  2449. /**
  2450. * pci_request_region - Reserve PCI I/O and memory resource
  2451. * @pdev: PCI device whose resources are to be reserved
  2452. * @bar: BAR to be reserved
  2453. * @res_name: Name to be associated with resource
  2454. *
  2455. * Mark the PCI region associated with PCI device @pdev BAR @bar as
  2456. * being reserved by owner @res_name. Do not access any
  2457. * address inside the PCI regions unless this call returns
  2458. * successfully.
  2459. *
  2460. * Returns 0 on success, or %EBUSY on error. A warning
  2461. * message is also printed on failure.
  2462. */
  2463. int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
  2464. {
  2465. return __pci_request_region(pdev, bar, res_name, 0);
  2466. }
  2467. EXPORT_SYMBOL(pci_request_region);
  2468. /**
  2469. * pci_request_region_exclusive - Reserved PCI I/O and memory resource
  2470. * @pdev: PCI device whose resources are to be reserved
  2471. * @bar: BAR to be reserved
  2472. * @res_name: Name to be associated with resource.
  2473. *
  2474. * Mark the PCI region associated with PCI device @pdev BR @bar as
  2475. * being reserved by owner @res_name. Do not access any
  2476. * address inside the PCI regions unless this call returns
  2477. * successfully.
  2478. *
  2479. * Returns 0 on success, or %EBUSY on error. A warning
  2480. * message is also printed on failure.
  2481. *
  2482. * The key difference that _exclusive makes it that userspace is
  2483. * explicitly not allowed to map the resource via /dev/mem or
  2484. * sysfs.
  2485. */
  2486. int pci_request_region_exclusive(struct pci_dev *pdev, int bar,
  2487. const char *res_name)
  2488. {
  2489. return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
  2490. }
  2491. EXPORT_SYMBOL(pci_request_region_exclusive);
  2492. /**
  2493. * pci_release_selected_regions - Release selected PCI I/O and memory resources
  2494. * @pdev: PCI device whose resources were previously reserved
  2495. * @bars: Bitmask of BARs to be released
  2496. *
  2497. * Release selected PCI I/O and memory resources previously reserved.
  2498. * Call this function only after all use of the PCI regions has ceased.
  2499. */
  2500. void pci_release_selected_regions(struct pci_dev *pdev, int bars)
  2501. {
  2502. int i;
  2503. for (i = 0; i < 6; i++)
  2504. if (bars & (1 << i))
  2505. pci_release_region(pdev, i);
  2506. }
  2507. EXPORT_SYMBOL(pci_release_selected_regions);
  2508. static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
  2509. const char *res_name, int excl)
  2510. {
  2511. int i;
  2512. for (i = 0; i < 6; i++)
  2513. if (bars & (1 << i))
  2514. if (__pci_request_region(pdev, i, res_name, excl))
  2515. goto err_out;
  2516. return 0;
  2517. err_out:
  2518. while (--i >= 0)
  2519. if (bars & (1 << i))
  2520. pci_release_region(pdev, i);
  2521. return -EBUSY;
  2522. }
  2523. /**
  2524. * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
  2525. * @pdev: PCI device whose resources are to be reserved
  2526. * @bars: Bitmask of BARs to be requested
  2527. * @res_name: Name to be associated with resource
  2528. */
  2529. int pci_request_selected_regions(struct pci_dev *pdev, int bars,
  2530. const char *res_name)
  2531. {
  2532. return __pci_request_selected_regions(pdev, bars, res_name, 0);
  2533. }
  2534. EXPORT_SYMBOL(pci_request_selected_regions);
  2535. int pci_request_selected_regions_exclusive(struct pci_dev *pdev, int bars,
  2536. const char *res_name)
  2537. {
  2538. return __pci_request_selected_regions(pdev, bars, res_name,
  2539. IORESOURCE_EXCLUSIVE);
  2540. }
  2541. EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
  2542. /**
  2543. * pci_release_regions - Release reserved PCI I/O and memory resources
  2544. * @pdev: PCI device whose resources were previously reserved by pci_request_regions
  2545. *
  2546. * Releases all PCI I/O and memory resources previously reserved by a
  2547. * successful call to pci_request_regions. Call this function only
  2548. * after all use of the PCI regions has ceased.
  2549. */
  2550. void pci_release_regions(struct pci_dev *pdev)
  2551. {
  2552. pci_release_selected_regions(pdev, (1 << 6) - 1);
  2553. }
  2554. EXPORT_SYMBOL(pci_release_regions);
  2555. /**
  2556. * pci_request_regions - Reserved PCI I/O and memory resources
  2557. * @pdev: PCI device whose resources are to be reserved
  2558. * @res_name: Name to be associated with resource.
  2559. *
  2560. * Mark all PCI regions associated with PCI device @pdev as
  2561. * being reserved by owner @res_name. Do not access any
  2562. * address inside the PCI regions unless this call returns
  2563. * successfully.
  2564. *
  2565. * Returns 0 on success, or %EBUSY on error. A warning
  2566. * message is also printed on failure.
  2567. */
  2568. int pci_request_regions(struct pci_dev *pdev, const char *res_name)
  2569. {
  2570. return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
  2571. }
  2572. EXPORT_SYMBOL(pci_request_regions);
  2573. /**
  2574. * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
  2575. * @pdev: PCI device whose resources are to be reserved
  2576. * @res_name: Name to be associated with resource.
  2577. *
  2578. * Mark all PCI regions associated with PCI device @pdev as
  2579. * being reserved by owner @res_name. Do not access any
  2580. * address inside the PCI regions unless this call returns
  2581. * successfully.
  2582. *
  2583. * pci_request_regions_exclusive() will mark the region so that
  2584. * /dev/mem and the sysfs MMIO access will not be allowed.
  2585. *
  2586. * Returns 0 on success, or %EBUSY on error. A warning
  2587. * message is also printed on failure.
  2588. */
  2589. int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
  2590. {
  2591. return pci_request_selected_regions_exclusive(pdev,
  2592. ((1 << 6) - 1), res_name);
  2593. }
  2594. EXPORT_SYMBOL(pci_request_regions_exclusive);
  2595. /**
  2596. * pci_remap_iospace - Remap the memory mapped I/O space
  2597. * @res: Resource describing the I/O space
  2598. * @phys_addr: physical address of range to be mapped
  2599. *
  2600. * Remap the memory mapped I/O space described by the @res
  2601. * and the CPU physical address @phys_addr into virtual address space.
  2602. * Only architectures that have memory mapped IO functions defined
  2603. * (and the PCI_IOBASE value defined) should call this function.
  2604. */
  2605. int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
  2606. {
  2607. #if defined(PCI_IOBASE) && defined(CONFIG_MMU)
  2608. unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
  2609. if (!(res->flags & IORESOURCE_IO))
  2610. return -EINVAL;
  2611. if (res->end > IO_SPACE_LIMIT)
  2612. return -EINVAL;
  2613. return ioremap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
  2614. pgprot_device(PAGE_KERNEL));
  2615. #else
  2616. /* this architecture does not have memory mapped I/O space,
  2617. so this function should never be called */
  2618. WARN_ONCE(1, "This architecture does not support memory mapped I/O\n");
  2619. return -ENODEV;
  2620. #endif
  2621. }
  2622. static void __pci_set_master(struct pci_dev *dev, bool enable)
  2623. {
  2624. u16 old_cmd, cmd;
  2625. pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
  2626. if (enable)
  2627. cmd = old_cmd | PCI_COMMAND_MASTER;
  2628. else
  2629. cmd = old_cmd & ~PCI_COMMAND_MASTER;
  2630. if (cmd != old_cmd) {
  2631. dev_dbg(&dev->dev, "%s bus mastering\n",
  2632. enable ? "enabling" : "disabling");
  2633. pci_write_config_word(dev, PCI_COMMAND, cmd);
  2634. }
  2635. dev->is_busmaster = enable;
  2636. }
  2637. /**
  2638. * pcibios_setup - process "pci=" kernel boot arguments
  2639. * @str: string used to pass in "pci=" kernel boot arguments
  2640. *
  2641. * Process kernel boot arguments. This is the default implementation.
  2642. * Architecture specific implementations can override this as necessary.
  2643. */
  2644. char * __weak __init pcibios_setup(char *str)
  2645. {
  2646. return str;
  2647. }
  2648. /**
  2649. * pcibios_set_master - enable PCI bus-mastering for device dev
  2650. * @dev: the PCI device to enable
  2651. *
  2652. * Enables PCI bus-mastering for the device. This is the default
  2653. * implementation. Architecture specific implementations can override
  2654. * this if necessary.
  2655. */
  2656. void __weak pcibios_set_master(struct pci_dev *dev)
  2657. {
  2658. u8 lat;
  2659. /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
  2660. if (pci_is_pcie(dev))
  2661. return;
  2662. pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
  2663. if (lat < 16)
  2664. lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
  2665. else if (lat > pcibios_max_latency)
  2666. lat = pcibios_max_latency;
  2667. else
  2668. return;
  2669. pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
  2670. }
  2671. /**
  2672. * pci_set_master - enables bus-mastering for device dev
  2673. * @dev: the PCI device to enable
  2674. *
  2675. * Enables bus-mastering on the device and calls pcibios_set_master()
  2676. * to do the needed arch specific settings.
  2677. */
  2678. void pci_set_master(struct pci_dev *dev)
  2679. {
  2680. __pci_set_master(dev, true);
  2681. pcibios_set_master(dev);
  2682. }
  2683. EXPORT_SYMBOL(pci_set_master);
  2684. /**
  2685. * pci_clear_master - disables bus-mastering for device dev
  2686. * @dev: the PCI device to disable
  2687. */
  2688. void pci_clear_master(struct pci_dev *dev)
  2689. {
  2690. __pci_set_master(dev, false);
  2691. }
  2692. EXPORT_SYMBOL(pci_clear_master);
  2693. /**
  2694. * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
  2695. * @dev: the PCI device for which MWI is to be enabled
  2696. *
  2697. * Helper function for pci_set_mwi.
  2698. * Originally copied from drivers/net/acenic.c.
  2699. * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
  2700. *
  2701. * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
  2702. */
  2703. int pci_set_cacheline_size(struct pci_dev *dev)
  2704. {
  2705. u8 cacheline_size;
  2706. if (!pci_cache_line_size)
  2707. return -EINVAL;
  2708. /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
  2709. equal to or multiple of the right value. */
  2710. pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
  2711. if (cacheline_size >= pci_cache_line_size &&
  2712. (cacheline_size % pci_cache_line_size) == 0)
  2713. return 0;
  2714. /* Write the correct value. */
  2715. pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
  2716. /* Read it back. */
  2717. pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
  2718. if (cacheline_size == pci_cache_line_size)
  2719. return 0;
  2720. dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not supported\n",
  2721. pci_cache_line_size << 2);
  2722. return -EINVAL;
  2723. }
  2724. EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
  2725. /**
  2726. * pci_set_mwi - enables memory-write-invalidate PCI transaction
  2727. * @dev: the PCI device for which MWI is enabled
  2728. *
  2729. * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
  2730. *
  2731. * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
  2732. */
  2733. int pci_set_mwi(struct pci_dev *dev)
  2734. {
  2735. #ifdef PCI_DISABLE_MWI
  2736. return 0;
  2737. #else
  2738. int rc;
  2739. u16 cmd;
  2740. rc = pci_set_cacheline_size(dev);
  2741. if (rc)
  2742. return rc;
  2743. pci_read_config_word(dev, PCI_COMMAND, &cmd);
  2744. if (!(cmd & PCI_COMMAND_INVALIDATE)) {
  2745. dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
  2746. cmd |= PCI_COMMAND_INVALIDATE;
  2747. pci_write_config_word(dev, PCI_COMMAND, cmd);
  2748. }
  2749. return 0;
  2750. #endif
  2751. }
  2752. EXPORT_SYMBOL(pci_set_mwi);
  2753. /**
  2754. * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
  2755. * @dev: the PCI device for which MWI is enabled
  2756. *
  2757. * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
  2758. * Callers are not required to check the return value.
  2759. *
  2760. * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
  2761. */
  2762. int pci_try_set_mwi(struct pci_dev *dev)
  2763. {
  2764. #ifdef PCI_DISABLE_MWI
  2765. return 0;
  2766. #else
  2767. return pci_set_mwi(dev);
  2768. #endif
  2769. }
  2770. EXPORT_SYMBOL(pci_try_set_mwi);
  2771. /**
  2772. * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
  2773. * @dev: the PCI device to disable
  2774. *
  2775. * Disables PCI Memory-Write-Invalidate transaction on the device
  2776. */
  2777. void pci_clear_mwi(struct pci_dev *dev)
  2778. {
  2779. #ifndef PCI_DISABLE_MWI
  2780. u16 cmd;
  2781. pci_read_config_word(dev, PCI_COMMAND, &cmd);
  2782. if (cmd & PCI_COMMAND_INVALIDATE) {
  2783. cmd &= ~PCI_COMMAND_INVALIDATE;
  2784. pci_write_config_word(dev, PCI_COMMAND, cmd);
  2785. }
  2786. #endif
  2787. }
  2788. EXPORT_SYMBOL(pci_clear_mwi);
  2789. /**
  2790. * pci_intx - enables/disables PCI INTx for device dev
  2791. * @pdev: the PCI device to operate on
  2792. * @enable: boolean: whether to enable or disable PCI INTx
  2793. *
  2794. * Enables/disables PCI INTx for device dev
  2795. */
  2796. void pci_intx(struct pci_dev *pdev, int enable)
  2797. {
  2798. u16 pci_command, new;
  2799. pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
  2800. if (enable)
  2801. new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
  2802. else
  2803. new = pci_command | PCI_COMMAND_INTX_DISABLE;
  2804. if (new != pci_command) {
  2805. struct pci_devres *dr;
  2806. pci_write_config_word(pdev, PCI_COMMAND, new);
  2807. dr = find_pci_dr(pdev);
  2808. if (dr && !dr->restore_intx) {
  2809. dr->restore_intx = 1;
  2810. dr->orig_intx = !enable;
  2811. }
  2812. }
  2813. }
  2814. EXPORT_SYMBOL_GPL(pci_intx);
  2815. /**
  2816. * pci_intx_mask_supported - probe for INTx masking support
  2817. * @dev: the PCI device to operate on
  2818. *
  2819. * Check if the device dev support INTx masking via the config space
  2820. * command word.
  2821. */
  2822. bool pci_intx_mask_supported(struct pci_dev *dev)
  2823. {
  2824. bool mask_supported = false;
  2825. u16 orig, new;
  2826. if (dev->broken_intx_masking)
  2827. return false;
  2828. pci_cfg_access_lock(dev);
  2829. pci_read_config_word(dev, PCI_COMMAND, &orig);
  2830. pci_write_config_word(dev, PCI_COMMAND,
  2831. orig ^ PCI_COMMAND_INTX_DISABLE);
  2832. pci_read_config_word(dev, PCI_COMMAND, &new);
  2833. /*
  2834. * There's no way to protect against hardware bugs or detect them
  2835. * reliably, but as long as we know what the value should be, let's
  2836. * go ahead and check it.
  2837. */
  2838. if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
  2839. dev_err(&dev->dev, "Command register changed from 0x%x to 0x%x: driver or hardware bug?\n",
  2840. orig, new);
  2841. } else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) {
  2842. mask_supported = true;
  2843. pci_write_config_word(dev, PCI_COMMAND, orig);
  2844. }
  2845. pci_cfg_access_unlock(dev);
  2846. return mask_supported;
  2847. }
  2848. EXPORT_SYMBOL_GPL(pci_intx_mask_supported);
  2849. static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
  2850. {
  2851. struct pci_bus *bus = dev->bus;
  2852. bool mask_updated = true;
  2853. u32 cmd_status_dword;
  2854. u16 origcmd, newcmd;
  2855. unsigned long flags;
  2856. bool irq_pending;
  2857. /*
  2858. * We do a single dword read to retrieve both command and status.
  2859. * Document assumptions that make this possible.
  2860. */
  2861. BUILD_BUG_ON(PCI_COMMAND % 4);
  2862. BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
  2863. raw_spin_lock_irqsave(&pci_lock, flags);
  2864. bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
  2865. irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
  2866. /*
  2867. * Check interrupt status register to see whether our device
  2868. * triggered the interrupt (when masking) or the next IRQ is
  2869. * already pending (when unmasking).
  2870. */
  2871. if (mask != irq_pending) {
  2872. mask_updated = false;
  2873. goto done;
  2874. }
  2875. origcmd = cmd_status_dword;
  2876. newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
  2877. if (mask)
  2878. newcmd |= PCI_COMMAND_INTX_DISABLE;
  2879. if (newcmd != origcmd)
  2880. bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
  2881. done:
  2882. raw_spin_unlock_irqrestore(&pci_lock, flags);
  2883. return mask_updated;
  2884. }
  2885. /**
  2886. * pci_check_and_mask_intx - mask INTx on pending interrupt
  2887. * @dev: the PCI device to operate on
  2888. *
  2889. * Check if the device dev has its INTx line asserted, mask it and
  2890. * return true in that case. False is returned if not interrupt was
  2891. * pending.
  2892. */
  2893. bool pci_check_and_mask_intx(struct pci_dev *dev)
  2894. {
  2895. return pci_check_and_set_intx_mask(dev, true);
  2896. }
  2897. EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
  2898. /**
  2899. * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
  2900. * @dev: the PCI device to operate on
  2901. *
  2902. * Check if the device dev has its INTx line asserted, unmask it if not
  2903. * and return true. False is returned and the mask remains active if
  2904. * there was still an interrupt pending.
  2905. */
  2906. bool pci_check_and_unmask_intx(struct pci_dev *dev)
  2907. {
  2908. return pci_check_and_set_intx_mask(dev, false);
  2909. }
  2910. EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
  2911. int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
  2912. {
  2913. return dma_set_max_seg_size(&dev->dev, size);
  2914. }
  2915. EXPORT_SYMBOL(pci_set_dma_max_seg_size);
  2916. int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
  2917. {
  2918. return dma_set_seg_boundary(&dev->dev, mask);
  2919. }
  2920. EXPORT_SYMBOL(pci_set_dma_seg_boundary);
  2921. /**
  2922. * pci_wait_for_pending_transaction - waits for pending transaction
  2923. * @dev: the PCI device to operate on
  2924. *
  2925. * Return 0 if transaction is pending 1 otherwise.
  2926. */
  2927. int pci_wait_for_pending_transaction(struct pci_dev *dev)
  2928. {
  2929. if (!pci_is_pcie(dev))
  2930. return 1;
  2931. return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
  2932. PCI_EXP_DEVSTA_TRPND);
  2933. }
  2934. EXPORT_SYMBOL(pci_wait_for_pending_transaction);
  2935. static int pcie_flr(struct pci_dev *dev, int probe)
  2936. {
  2937. u32 cap;
  2938. pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
  2939. if (!(cap & PCI_EXP_DEVCAP_FLR))
  2940. return -ENOTTY;
  2941. if (probe)
  2942. return 0;
  2943. if (!pci_wait_for_pending_transaction(dev))
  2944. dev_err(&dev->dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
  2945. pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
  2946. msleep(100);
  2947. return 0;
  2948. }
  2949. static int pci_af_flr(struct pci_dev *dev, int probe)
  2950. {
  2951. int pos;
  2952. u8 cap;
  2953. pos = pci_find_capability(dev, PCI_CAP_ID_AF);
  2954. if (!pos)
  2955. return -ENOTTY;
  2956. pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
  2957. if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
  2958. return -ENOTTY;
  2959. if (probe)
  2960. return 0;
  2961. /*
  2962. * Wait for Transaction Pending bit to clear. A word-aligned test
  2963. * is used, so we use the conrol offset rather than status and shift
  2964. * the test bit to match.
  2965. */
  2966. if (!pci_wait_for_pending(dev, pos + PCI_AF_CTRL,
  2967. PCI_AF_STATUS_TP << 8))
  2968. dev_err(&dev->dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
  2969. pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
  2970. msleep(100);
  2971. return 0;
  2972. }
  2973. /**
  2974. * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
  2975. * @dev: Device to reset.
  2976. * @probe: If set, only check if the device can be reset this way.
  2977. *
  2978. * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
  2979. * unset, it will be reinitialized internally when going from PCI_D3hot to
  2980. * PCI_D0. If that's the case and the device is not in a low-power state
  2981. * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
  2982. *
  2983. * NOTE: This causes the caller to sleep for twice the device power transition
  2984. * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
  2985. * by default (i.e. unless the @dev's d3_delay field has a different value).
  2986. * Moreover, only devices in D0 can be reset by this function.
  2987. */
  2988. static int pci_pm_reset(struct pci_dev *dev, int probe)
  2989. {
  2990. u16 csr;
  2991. if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
  2992. return -ENOTTY;
  2993. pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
  2994. if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
  2995. return -ENOTTY;
  2996. if (probe)
  2997. return 0;
  2998. if (dev->current_state != PCI_D0)
  2999. return -EINVAL;
  3000. csr &= ~PCI_PM_CTRL_STATE_MASK;
  3001. csr |= PCI_D3hot;
  3002. pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
  3003. pci_dev_d3_sleep(dev);
  3004. csr &= ~PCI_PM_CTRL_STATE_MASK;
  3005. csr |= PCI_D0;
  3006. pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
  3007. pci_dev_d3_sleep(dev);
  3008. return 0;
  3009. }
  3010. void pci_reset_secondary_bus(struct pci_dev *dev)
  3011. {
  3012. u16 ctrl;
  3013. pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
  3014. ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
  3015. pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
  3016. /*
  3017. * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double
  3018. * this to 2ms to ensure that we meet the minimum requirement.
  3019. */
  3020. msleep(2);
  3021. ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
  3022. pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
  3023. /*
  3024. * Trhfa for conventional PCI is 2^25 clock cycles.
  3025. * Assuming a minimum 33MHz clock this results in a 1s
  3026. * delay before we can consider subordinate devices to
  3027. * be re-initialized. PCIe has some ways to shorten this,
  3028. * but we don't make use of them yet.
  3029. */
  3030. ssleep(1);
  3031. }
  3032. void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
  3033. {
  3034. pci_reset_secondary_bus(dev);
  3035. }
  3036. /**
  3037. * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
  3038. * @dev: Bridge device
  3039. *
  3040. * Use the bridge control register to assert reset on the secondary bus.
  3041. * Devices on the secondary bus are left in power-on state.
  3042. */
  3043. void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
  3044. {
  3045. pcibios_reset_secondary_bus(dev);
  3046. }
  3047. EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
  3048. static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
  3049. {
  3050. struct pci_dev *pdev;
  3051. if (pci_is_root_bus(dev->bus) || dev->subordinate ||
  3052. !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
  3053. return -ENOTTY;
  3054. list_for_each_entry(pdev, &dev->bus->devices, bus_list)
  3055. if (pdev != dev)
  3056. return -ENOTTY;
  3057. if (probe)
  3058. return 0;
  3059. pci_reset_bridge_secondary_bus(dev->bus->self);
  3060. return 0;
  3061. }
  3062. static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
  3063. {
  3064. int rc = -ENOTTY;
  3065. if (!hotplug || !try_module_get(hotplug->ops->owner))
  3066. return rc;
  3067. if (hotplug->ops->reset_slot)
  3068. rc = hotplug->ops->reset_slot(hotplug, probe);
  3069. module_put(hotplug->ops->owner);
  3070. return rc;
  3071. }
  3072. static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
  3073. {
  3074. struct pci_dev *pdev;
  3075. if (dev->subordinate || !dev->slot ||
  3076. dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
  3077. return -ENOTTY;
  3078. list_for_each_entry(pdev, &dev->bus->devices, bus_list)
  3079. if (pdev != dev && pdev->slot == dev->slot)
  3080. return -ENOTTY;
  3081. return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
  3082. }
  3083. static int __pci_dev_reset(struct pci_dev *dev, int probe)
  3084. {
  3085. int rc;
  3086. might_sleep();
  3087. rc = pci_dev_specific_reset(dev, probe);
  3088. if (rc != -ENOTTY)
  3089. goto done;
  3090. rc = pcie_flr(dev, probe);
  3091. if (rc != -ENOTTY)
  3092. goto done;
  3093. rc = pci_af_flr(dev, probe);
  3094. if (rc != -ENOTTY)
  3095. goto done;
  3096. rc = pci_pm_reset(dev, probe);
  3097. if (rc != -ENOTTY)
  3098. goto done;
  3099. rc = pci_dev_reset_slot_function(dev, probe);
  3100. if (rc != -ENOTTY)
  3101. goto done;
  3102. rc = pci_parent_bus_reset(dev, probe);
  3103. done:
  3104. return rc;
  3105. }
  3106. static void pci_dev_lock(struct pci_dev *dev)
  3107. {
  3108. pci_cfg_access_lock(dev);
  3109. /* block PM suspend, driver probe, etc. */
  3110. device_lock(&dev->dev);
  3111. }
  3112. /* Return 1 on successful lock, 0 on contention */
  3113. static int pci_dev_trylock(struct pci_dev *dev)
  3114. {
  3115. if (pci_cfg_access_trylock(dev)) {
  3116. if (device_trylock(&dev->dev))
  3117. return 1;
  3118. pci_cfg_access_unlock(dev);
  3119. }
  3120. return 0;
  3121. }
  3122. static void pci_dev_unlock(struct pci_dev *dev)
  3123. {
  3124. device_unlock(&dev->dev);
  3125. pci_cfg_access_unlock(dev);
  3126. }
  3127. /**
  3128. * pci_reset_notify - notify device driver of reset
  3129. * @dev: device to be notified of reset
  3130. * @prepare: 'true' if device is about to be reset; 'false' if reset attempt
  3131. * completed
  3132. *
  3133. * Must be called prior to device access being disabled and after device
  3134. * access is restored.
  3135. */
  3136. static void pci_reset_notify(struct pci_dev *dev, bool prepare)
  3137. {
  3138. const struct pci_error_handlers *err_handler =
  3139. dev->driver ? dev->driver->err_handler : NULL;
  3140. if (err_handler && err_handler->reset_notify)
  3141. err_handler->reset_notify(dev, prepare);
  3142. }
  3143. static void pci_dev_save_and_disable(struct pci_dev *dev)
  3144. {
  3145. pci_reset_notify(dev, true);
  3146. /*
  3147. * Wake-up device prior to save. PM registers default to D0 after
  3148. * reset and a simple register restore doesn't reliably return
  3149. * to a non-D0 state anyway.
  3150. */
  3151. pci_set_power_state(dev, PCI_D0);
  3152. pci_save_state(dev);
  3153. /*
  3154. * Disable the device by clearing the Command register, except for
  3155. * INTx-disable which is set. This not only disables MMIO and I/O port
  3156. * BARs, but also prevents the device from being Bus Master, preventing
  3157. * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3
  3158. * compliant devices, INTx-disable prevents legacy interrupts.
  3159. */
  3160. pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
  3161. }
  3162. static void pci_dev_restore(struct pci_dev *dev)
  3163. {
  3164. pci_restore_state(dev);
  3165. pci_reset_notify(dev, false);
  3166. }
  3167. static int pci_dev_reset(struct pci_dev *dev, int probe)
  3168. {
  3169. int rc;
  3170. if (!probe)
  3171. pci_dev_lock(dev);
  3172. rc = __pci_dev_reset(dev, probe);
  3173. if (!probe)
  3174. pci_dev_unlock(dev);
  3175. return rc;
  3176. }
  3177. /**
  3178. * __pci_reset_function - reset a PCI device function
  3179. * @dev: PCI device to reset
  3180. *
  3181. * Some devices allow an individual function to be reset without affecting
  3182. * other functions in the same device. The PCI device must be responsive
  3183. * to PCI config space in order to use this function.
  3184. *
  3185. * The device function is presumed to be unused when this function is called.
  3186. * Resetting the device will make the contents of PCI configuration space
  3187. * random, so any caller of this must be prepared to reinitialise the
  3188. * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
  3189. * etc.
  3190. *
  3191. * Returns 0 if the device function was successfully reset or negative if the
  3192. * device doesn't support resetting a single function.
  3193. */
  3194. int __pci_reset_function(struct pci_dev *dev)
  3195. {
  3196. return pci_dev_reset(dev, 0);
  3197. }
  3198. EXPORT_SYMBOL_GPL(__pci_reset_function);
  3199. /**
  3200. * __pci_reset_function_locked - reset a PCI device function while holding
  3201. * the @dev mutex lock.
  3202. * @dev: PCI device to reset
  3203. *
  3204. * Some devices allow an individual function to be reset without affecting
  3205. * other functions in the same device. The PCI device must be responsive
  3206. * to PCI config space in order to use this function.
  3207. *
  3208. * The device function is presumed to be unused and the caller is holding
  3209. * the device mutex lock when this function is called.
  3210. * Resetting the device will make the contents of PCI configuration space
  3211. * random, so any caller of this must be prepared to reinitialise the
  3212. * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
  3213. * etc.
  3214. *
  3215. * Returns 0 if the device function was successfully reset or negative if the
  3216. * device doesn't support resetting a single function.
  3217. */
  3218. int __pci_reset_function_locked(struct pci_dev *dev)
  3219. {
  3220. return __pci_dev_reset(dev, 0);
  3221. }
  3222. EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
  3223. /**
  3224. * pci_probe_reset_function - check whether the device can be safely reset
  3225. * @dev: PCI device to reset
  3226. *
  3227. * Some devices allow an individual function to be reset without affecting
  3228. * other functions in the same device. The PCI device must be responsive
  3229. * to PCI config space in order to use this function.
  3230. *
  3231. * Returns 0 if the device function can be reset or negative if the
  3232. * device doesn't support resetting a single function.
  3233. */
  3234. int pci_probe_reset_function(struct pci_dev *dev)
  3235. {
  3236. return pci_dev_reset(dev, 1);
  3237. }
  3238. /**
  3239. * pci_reset_function - quiesce and reset a PCI device function
  3240. * @dev: PCI device to reset
  3241. *
  3242. * Some devices allow an individual function to be reset without affecting
  3243. * other functions in the same device. The PCI device must be responsive
  3244. * to PCI config space in order to use this function.
  3245. *
  3246. * This function does not just reset the PCI portion of a device, but
  3247. * clears all the state associated with the device. This function differs
  3248. * from __pci_reset_function in that it saves and restores device state
  3249. * over the reset.
  3250. *
  3251. * Returns 0 if the device function was successfully reset or negative if the
  3252. * device doesn't support resetting a single function.
  3253. */
  3254. int pci_reset_function(struct pci_dev *dev)
  3255. {
  3256. int rc;
  3257. rc = pci_dev_reset(dev, 1);
  3258. if (rc)
  3259. return rc;
  3260. pci_dev_save_and_disable(dev);
  3261. rc = pci_dev_reset(dev, 0);
  3262. pci_dev_restore(dev);
  3263. return rc;
  3264. }
  3265. EXPORT_SYMBOL_GPL(pci_reset_function);
  3266. /**
  3267. * pci_try_reset_function - quiesce and reset a PCI device function
  3268. * @dev: PCI device to reset
  3269. *
  3270. * Same as above, except return -EAGAIN if unable to lock device.
  3271. */
  3272. int pci_try_reset_function(struct pci_dev *dev)
  3273. {
  3274. int rc;
  3275. rc = pci_dev_reset(dev, 1);
  3276. if (rc)
  3277. return rc;
  3278. pci_dev_save_and_disable(dev);
  3279. if (pci_dev_trylock(dev)) {
  3280. rc = __pci_dev_reset(dev, 0);
  3281. pci_dev_unlock(dev);
  3282. } else
  3283. rc = -EAGAIN;
  3284. pci_dev_restore(dev);
  3285. return rc;
  3286. }
  3287. EXPORT_SYMBOL_GPL(pci_try_reset_function);
  3288. /* Do any devices on or below this bus prevent a bus reset? */
  3289. static bool pci_bus_resetable(struct pci_bus *bus)
  3290. {
  3291. struct pci_dev *dev;
  3292. if (bus->self && (bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
  3293. return false;
  3294. list_for_each_entry(dev, &bus->devices, bus_list) {
  3295. if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
  3296. (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
  3297. return false;
  3298. }
  3299. return true;
  3300. }
  3301. /* Lock devices from the top of the tree down */
  3302. static void pci_bus_lock(struct pci_bus *bus)
  3303. {
  3304. struct pci_dev *dev;
  3305. list_for_each_entry(dev, &bus->devices, bus_list) {
  3306. pci_dev_lock(dev);
  3307. if (dev->subordinate)
  3308. pci_bus_lock(dev->subordinate);
  3309. }
  3310. }
  3311. /* Unlock devices from the bottom of the tree up */
  3312. static void pci_bus_unlock(struct pci_bus *bus)
  3313. {
  3314. struct pci_dev *dev;
  3315. list_for_each_entry(dev, &bus->devices, bus_list) {
  3316. if (dev->subordinate)
  3317. pci_bus_unlock(dev->subordinate);
  3318. pci_dev_unlock(dev);
  3319. }
  3320. }
  3321. /* Return 1 on successful lock, 0 on contention */
  3322. static int pci_bus_trylock(struct pci_bus *bus)
  3323. {
  3324. struct pci_dev *dev;
  3325. list_for_each_entry(dev, &bus->devices, bus_list) {
  3326. if (!pci_dev_trylock(dev))
  3327. goto unlock;
  3328. if (dev->subordinate) {
  3329. if (!pci_bus_trylock(dev->subordinate)) {
  3330. pci_dev_unlock(dev);
  3331. goto unlock;
  3332. }
  3333. }
  3334. }
  3335. return 1;
  3336. unlock:
  3337. list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
  3338. if (dev->subordinate)
  3339. pci_bus_unlock(dev->subordinate);
  3340. pci_dev_unlock(dev);
  3341. }
  3342. return 0;
  3343. }
  3344. /* Do any devices on or below this slot prevent a bus reset? */
  3345. static bool pci_slot_resetable(struct pci_slot *slot)
  3346. {
  3347. struct pci_dev *dev;
  3348. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3349. if (!dev->slot || dev->slot != slot)
  3350. continue;
  3351. if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
  3352. (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
  3353. return false;
  3354. }
  3355. return true;
  3356. }
  3357. /* Lock devices from the top of the tree down */
  3358. static void pci_slot_lock(struct pci_slot *slot)
  3359. {
  3360. struct pci_dev *dev;
  3361. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3362. if (!dev->slot || dev->slot != slot)
  3363. continue;
  3364. pci_dev_lock(dev);
  3365. if (dev->subordinate)
  3366. pci_bus_lock(dev->subordinate);
  3367. }
  3368. }
  3369. /* Unlock devices from the bottom of the tree up */
  3370. static void pci_slot_unlock(struct pci_slot *slot)
  3371. {
  3372. struct pci_dev *dev;
  3373. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3374. if (!dev->slot || dev->slot != slot)
  3375. continue;
  3376. if (dev->subordinate)
  3377. pci_bus_unlock(dev->subordinate);
  3378. pci_dev_unlock(dev);
  3379. }
  3380. }
  3381. /* Return 1 on successful lock, 0 on contention */
  3382. static int pci_slot_trylock(struct pci_slot *slot)
  3383. {
  3384. struct pci_dev *dev;
  3385. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3386. if (!dev->slot || dev->slot != slot)
  3387. continue;
  3388. if (!pci_dev_trylock(dev))
  3389. goto unlock;
  3390. if (dev->subordinate) {
  3391. if (!pci_bus_trylock(dev->subordinate)) {
  3392. pci_dev_unlock(dev);
  3393. goto unlock;
  3394. }
  3395. }
  3396. }
  3397. return 1;
  3398. unlock:
  3399. list_for_each_entry_continue_reverse(dev,
  3400. &slot->bus->devices, bus_list) {
  3401. if (!dev->slot || dev->slot != slot)
  3402. continue;
  3403. if (dev->subordinate)
  3404. pci_bus_unlock(dev->subordinate);
  3405. pci_dev_unlock(dev);
  3406. }
  3407. return 0;
  3408. }
  3409. /* Save and disable devices from the top of the tree down */
  3410. static void pci_bus_save_and_disable(struct pci_bus *bus)
  3411. {
  3412. struct pci_dev *dev;
  3413. list_for_each_entry(dev, &bus->devices, bus_list) {
  3414. pci_dev_save_and_disable(dev);
  3415. if (dev->subordinate)
  3416. pci_bus_save_and_disable(dev->subordinate);
  3417. }
  3418. }
  3419. /*
  3420. * Restore devices from top of the tree down - parent bridges need to be
  3421. * restored before we can get to subordinate devices.
  3422. */
  3423. static void pci_bus_restore(struct pci_bus *bus)
  3424. {
  3425. struct pci_dev *dev;
  3426. list_for_each_entry(dev, &bus->devices, bus_list) {
  3427. pci_dev_restore(dev);
  3428. if (dev->subordinate)
  3429. pci_bus_restore(dev->subordinate);
  3430. }
  3431. }
  3432. /* Save and disable devices from the top of the tree down */
  3433. static void pci_slot_save_and_disable(struct pci_slot *slot)
  3434. {
  3435. struct pci_dev *dev;
  3436. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3437. if (!dev->slot || dev->slot != slot)
  3438. continue;
  3439. pci_dev_save_and_disable(dev);
  3440. if (dev->subordinate)
  3441. pci_bus_save_and_disable(dev->subordinate);
  3442. }
  3443. }
  3444. /*
  3445. * Restore devices from top of the tree down - parent bridges need to be
  3446. * restored before we can get to subordinate devices.
  3447. */
  3448. static void pci_slot_restore(struct pci_slot *slot)
  3449. {
  3450. struct pci_dev *dev;
  3451. list_for_each_entry(dev, &slot->bus->devices, bus_list) {
  3452. if (!dev->slot || dev->slot != slot)
  3453. continue;
  3454. pci_dev_restore(dev);
  3455. if (dev->subordinate)
  3456. pci_bus_restore(dev->subordinate);
  3457. }
  3458. }
  3459. static int pci_slot_reset(struct pci_slot *slot, int probe)
  3460. {
  3461. int rc;
  3462. if (!slot || !pci_slot_resetable(slot))
  3463. return -ENOTTY;
  3464. if (!probe)
  3465. pci_slot_lock(slot);
  3466. might_sleep();
  3467. rc = pci_reset_hotplug_slot(slot->hotplug, probe);
  3468. if (!probe)
  3469. pci_slot_unlock(slot);
  3470. return rc;
  3471. }
  3472. /**
  3473. * pci_probe_reset_slot - probe whether a PCI slot can be reset
  3474. * @slot: PCI slot to probe
  3475. *
  3476. * Return 0 if slot can be reset, negative if a slot reset is not supported.
  3477. */
  3478. int pci_probe_reset_slot(struct pci_slot *slot)
  3479. {
  3480. return pci_slot_reset(slot, 1);
  3481. }
  3482. EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
  3483. /**
  3484. * pci_reset_slot - reset a PCI slot
  3485. * @slot: PCI slot to reset
  3486. *
  3487. * A PCI bus may host multiple slots, each slot may support a reset mechanism
  3488. * independent of other slots. For instance, some slots may support slot power
  3489. * control. In the case of a 1:1 bus to slot architecture, this function may
  3490. * wrap the bus reset to avoid spurious slot related events such as hotplug.
  3491. * Generally a slot reset should be attempted before a bus reset. All of the
  3492. * function of the slot and any subordinate buses behind the slot are reset
  3493. * through this function. PCI config space of all devices in the slot and
  3494. * behind the slot is saved before and restored after reset.
  3495. *
  3496. * Return 0 on success, non-zero on error.
  3497. */
  3498. int pci_reset_slot(struct pci_slot *slot)
  3499. {
  3500. int rc;
  3501. rc = pci_slot_reset(slot, 1);
  3502. if (rc)
  3503. return rc;
  3504. pci_slot_save_and_disable(slot);
  3505. rc = pci_slot_reset(slot, 0);
  3506. pci_slot_restore(slot);
  3507. return rc;
  3508. }
  3509. EXPORT_SYMBOL_GPL(pci_reset_slot);
  3510. /**
  3511. * pci_try_reset_slot - Try to reset a PCI slot
  3512. * @slot: PCI slot to reset
  3513. *
  3514. * Same as above except return -EAGAIN if the slot cannot be locked
  3515. */
  3516. int pci_try_reset_slot(struct pci_slot *slot)
  3517. {
  3518. int rc;
  3519. rc = pci_slot_reset(slot, 1);
  3520. if (rc)
  3521. return rc;
  3522. pci_slot_save_and_disable(slot);
  3523. if (pci_slot_trylock(slot)) {
  3524. might_sleep();
  3525. rc = pci_reset_hotplug_slot(slot->hotplug, 0);
  3526. pci_slot_unlock(slot);
  3527. } else
  3528. rc = -EAGAIN;
  3529. pci_slot_restore(slot);
  3530. return rc;
  3531. }
  3532. EXPORT_SYMBOL_GPL(pci_try_reset_slot);
  3533. static int pci_bus_reset(struct pci_bus *bus, int probe)
  3534. {
  3535. if (!bus->self || !pci_bus_resetable(bus))
  3536. return -ENOTTY;
  3537. if (probe)
  3538. return 0;
  3539. pci_bus_lock(bus);
  3540. might_sleep();
  3541. pci_reset_bridge_secondary_bus(bus->self);
  3542. pci_bus_unlock(bus);
  3543. return 0;
  3544. }
  3545. /**
  3546. * pci_probe_reset_bus - probe whether a PCI bus can be reset
  3547. * @bus: PCI bus to probe
  3548. *
  3549. * Return 0 if bus can be reset, negative if a bus reset is not supported.
  3550. */
  3551. int pci_probe_reset_bus(struct pci_bus *bus)
  3552. {
  3553. return pci_bus_reset(bus, 1);
  3554. }
  3555. EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
  3556. /**
  3557. * pci_reset_bus - reset a PCI bus
  3558. * @bus: top level PCI bus to reset
  3559. *
  3560. * Do a bus reset on the given bus and any subordinate buses, saving
  3561. * and restoring state of all devices.
  3562. *
  3563. * Return 0 on success, non-zero on error.
  3564. */
  3565. int pci_reset_bus(struct pci_bus *bus)
  3566. {
  3567. int rc;
  3568. rc = pci_bus_reset(bus, 1);
  3569. if (rc)
  3570. return rc;
  3571. pci_bus_save_and_disable(bus);
  3572. rc = pci_bus_reset(bus, 0);
  3573. pci_bus_restore(bus);
  3574. return rc;
  3575. }
  3576. EXPORT_SYMBOL_GPL(pci_reset_bus);
  3577. /**
  3578. * pci_try_reset_bus - Try to reset a PCI bus
  3579. * @bus: top level PCI bus to reset
  3580. *
  3581. * Same as above except return -EAGAIN if the bus cannot be locked
  3582. */
  3583. int pci_try_reset_bus(struct pci_bus *bus)
  3584. {
  3585. int rc;
  3586. rc = pci_bus_reset(bus, 1);
  3587. if (rc)
  3588. return rc;
  3589. pci_bus_save_and_disable(bus);
  3590. if (pci_bus_trylock(bus)) {
  3591. might_sleep();
  3592. pci_reset_bridge_secondary_bus(bus->self);
  3593. pci_bus_unlock(bus);
  3594. } else
  3595. rc = -EAGAIN;
  3596. pci_bus_restore(bus);
  3597. return rc;
  3598. }
  3599. EXPORT_SYMBOL_GPL(pci_try_reset_bus);
  3600. /**
  3601. * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
  3602. * @dev: PCI device to query
  3603. *
  3604. * Returns mmrbc: maximum designed memory read count in bytes
  3605. * or appropriate error value.
  3606. */
  3607. int pcix_get_max_mmrbc(struct pci_dev *dev)
  3608. {
  3609. int cap;
  3610. u32 stat;
  3611. cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
  3612. if (!cap)
  3613. return -EINVAL;
  3614. if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
  3615. return -EINVAL;
  3616. return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
  3617. }
  3618. EXPORT_SYMBOL(pcix_get_max_mmrbc);
  3619. /**
  3620. * pcix_get_mmrbc - get PCI-X maximum memory read byte count
  3621. * @dev: PCI device to query
  3622. *
  3623. * Returns mmrbc: maximum memory read count in bytes
  3624. * or appropriate error value.
  3625. */
  3626. int pcix_get_mmrbc(struct pci_dev *dev)
  3627. {
  3628. int cap;
  3629. u16 cmd;
  3630. cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
  3631. if (!cap)
  3632. return -EINVAL;
  3633. if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
  3634. return -EINVAL;
  3635. return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
  3636. }
  3637. EXPORT_SYMBOL(pcix_get_mmrbc);
  3638. /**
  3639. * pcix_set_mmrbc - set PCI-X maximum memory read byte count
  3640. * @dev: PCI device to query
  3641. * @mmrbc: maximum memory read count in bytes
  3642. * valid values are 512, 1024, 2048, 4096
  3643. *
  3644. * If possible sets maximum memory read byte count, some bridges have erratas
  3645. * that prevent this.
  3646. */
  3647. int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
  3648. {
  3649. int cap;
  3650. u32 stat, v, o;
  3651. u16 cmd;
  3652. if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
  3653. return -EINVAL;
  3654. v = ffs(mmrbc) - 10;
  3655. cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
  3656. if (!cap)
  3657. return -EINVAL;
  3658. if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
  3659. return -EINVAL;
  3660. if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
  3661. return -E2BIG;
  3662. if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
  3663. return -EINVAL;
  3664. o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
  3665. if (o != v) {
  3666. if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
  3667. return -EIO;
  3668. cmd &= ~PCI_X_CMD_MAX_READ;
  3669. cmd |= v << 2;
  3670. if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
  3671. return -EIO;
  3672. }
  3673. return 0;
  3674. }
  3675. EXPORT_SYMBOL(pcix_set_mmrbc);
  3676. /**
  3677. * pcie_get_readrq - get PCI Express read request size
  3678. * @dev: PCI device to query
  3679. *
  3680. * Returns maximum memory read request in bytes
  3681. * or appropriate error value.
  3682. */
  3683. int pcie_get_readrq(struct pci_dev *dev)
  3684. {
  3685. u16 ctl;
  3686. pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
  3687. return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
  3688. }
  3689. EXPORT_SYMBOL(pcie_get_readrq);
  3690. /**
  3691. * pcie_set_readrq - set PCI Express maximum memory read request
  3692. * @dev: PCI device to query
  3693. * @rq: maximum memory read count in bytes
  3694. * valid values are 128, 256, 512, 1024, 2048, 4096
  3695. *
  3696. * If possible sets maximum memory read request in bytes
  3697. */
  3698. int pcie_set_readrq(struct pci_dev *dev, int rq)
  3699. {
  3700. u16 v;
  3701. if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
  3702. return -EINVAL;
  3703. /*
  3704. * If using the "performance" PCIe config, we clamp the
  3705. * read rq size to the max packet size to prevent the
  3706. * host bridge generating requests larger than we can
  3707. * cope with
  3708. */
  3709. if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
  3710. int mps = pcie_get_mps(dev);
  3711. if (mps < rq)
  3712. rq = mps;
  3713. }
  3714. v = (ffs(rq) - 8) << 12;
  3715. return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
  3716. PCI_EXP_DEVCTL_READRQ, v);
  3717. }
  3718. EXPORT_SYMBOL(pcie_set_readrq);
  3719. /**
  3720. * pcie_get_mps - get PCI Express maximum payload size
  3721. * @dev: PCI device to query
  3722. *
  3723. * Returns maximum payload size in bytes
  3724. */
  3725. int pcie_get_mps(struct pci_dev *dev)
  3726. {
  3727. u16 ctl;
  3728. pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
  3729. return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
  3730. }
  3731. EXPORT_SYMBOL(pcie_get_mps);
  3732. /**
  3733. * pcie_set_mps - set PCI Express maximum payload size
  3734. * @dev: PCI device to query
  3735. * @mps: maximum payload size in bytes
  3736. * valid values are 128, 256, 512, 1024, 2048, 4096
  3737. *
  3738. * If possible sets maximum payload size
  3739. */
  3740. int pcie_set_mps(struct pci_dev *dev, int mps)
  3741. {
  3742. u16 v;
  3743. if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
  3744. return -EINVAL;
  3745. v = ffs(mps) - 8;
  3746. if (v > dev->pcie_mpss)
  3747. return -EINVAL;
  3748. v <<= 5;
  3749. return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
  3750. PCI_EXP_DEVCTL_PAYLOAD, v);
  3751. }
  3752. EXPORT_SYMBOL(pcie_set_mps);
  3753. /**
  3754. * pcie_get_minimum_link - determine minimum link settings of a PCI device
  3755. * @dev: PCI device to query
  3756. * @speed: storage for minimum speed
  3757. * @width: storage for minimum width
  3758. *
  3759. * This function will walk up the PCI device chain and determine the minimum
  3760. * link width and speed of the device.
  3761. */
  3762. int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
  3763. enum pcie_link_width *width)
  3764. {
  3765. int ret;
  3766. *speed = PCI_SPEED_UNKNOWN;
  3767. *width = PCIE_LNK_WIDTH_UNKNOWN;
  3768. while (dev) {
  3769. u16 lnksta;
  3770. enum pci_bus_speed next_speed;
  3771. enum pcie_link_width next_width;
  3772. ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
  3773. if (ret)
  3774. return ret;
  3775. next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
  3776. next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
  3777. PCI_EXP_LNKSTA_NLW_SHIFT;
  3778. if (next_speed < *speed)
  3779. *speed = next_speed;
  3780. if (next_width < *width)
  3781. *width = next_width;
  3782. dev = dev->bus->self;
  3783. }
  3784. return 0;
  3785. }
  3786. EXPORT_SYMBOL(pcie_get_minimum_link);
  3787. /**
  3788. * pci_select_bars - Make BAR mask from the type of resource
  3789. * @dev: the PCI device for which BAR mask is made
  3790. * @flags: resource type mask to be selected
  3791. *
  3792. * This helper routine makes bar mask from the type of resource.
  3793. */
  3794. int pci_select_bars(struct pci_dev *dev, unsigned long flags)
  3795. {
  3796. int i, bars = 0;
  3797. for (i = 0; i < PCI_NUM_RESOURCES; i++)
  3798. if (pci_resource_flags(dev, i) & flags)
  3799. bars |= (1 << i);
  3800. return bars;
  3801. }
  3802. EXPORT_SYMBOL(pci_select_bars);
  3803. /* Some architectures require additional programming to enable VGA */
  3804. static arch_set_vga_state_t arch_set_vga_state;
  3805. void __init pci_register_set_vga_state(arch_set_vga_state_t func)
  3806. {
  3807. arch_set_vga_state = func; /* NULL disables */
  3808. }
  3809. static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
  3810. unsigned int command_bits, u32 flags)
  3811. {
  3812. if (arch_set_vga_state)
  3813. return arch_set_vga_state(dev, decode, command_bits,
  3814. flags);
  3815. return 0;
  3816. }
  3817. /**
  3818. * pci_set_vga_state - set VGA decode state on device and parents if requested
  3819. * @dev: the PCI device
  3820. * @decode: true = enable decoding, false = disable decoding
  3821. * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
  3822. * @flags: traverse ancestors and change bridges
  3823. * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
  3824. */
  3825. int pci_set_vga_state(struct pci_dev *dev, bool decode,
  3826. unsigned int command_bits, u32 flags)
  3827. {
  3828. struct pci_bus *bus;
  3829. struct pci_dev *bridge;
  3830. u16 cmd;
  3831. int rc;
  3832. WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) && (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
  3833. /* ARCH specific VGA enables */
  3834. rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
  3835. if (rc)
  3836. return rc;
  3837. if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
  3838. pci_read_config_word(dev, PCI_COMMAND, &cmd);
  3839. if (decode == true)
  3840. cmd |= command_bits;
  3841. else
  3842. cmd &= ~command_bits;
  3843. pci_write_config_word(dev, PCI_COMMAND, cmd);
  3844. }
  3845. if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
  3846. return 0;
  3847. bus = dev->bus;
  3848. while (bus) {
  3849. bridge = bus->self;
  3850. if (bridge) {
  3851. pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
  3852. &cmd);
  3853. if (decode == true)
  3854. cmd |= PCI_BRIDGE_CTL_VGA;
  3855. else
  3856. cmd &= ~PCI_BRIDGE_CTL_VGA;
  3857. pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
  3858. cmd);
  3859. }
  3860. bus = bus->parent;
  3861. }
  3862. return 0;
  3863. }
  3864. bool pci_device_is_present(struct pci_dev *pdev)
  3865. {
  3866. u32 v;
  3867. return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
  3868. }
  3869. EXPORT_SYMBOL_GPL(pci_device_is_present);
  3870. void pci_ignore_hotplug(struct pci_dev *dev)
  3871. {
  3872. struct pci_dev *bridge = dev->bus->self;
  3873. dev->ignore_hotplug = 1;
  3874. /* Propagate the "ignore hotplug" setting to the parent bridge. */
  3875. if (bridge)
  3876. bridge->ignore_hotplug = 1;
  3877. }
  3878. EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
  3879. #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
  3880. static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
  3881. static DEFINE_SPINLOCK(resource_alignment_lock);
  3882. /**
  3883. * pci_specified_resource_alignment - get resource alignment specified by user.
  3884. * @dev: the PCI device to get
  3885. *
  3886. * RETURNS: Resource alignment if it is specified.
  3887. * Zero if it is not specified.
  3888. */
  3889. static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
  3890. {
  3891. int seg, bus, slot, func, align_order, count;
  3892. resource_size_t align = 0;
  3893. char *p;
  3894. spin_lock(&resource_alignment_lock);
  3895. p = resource_alignment_param;
  3896. while (*p) {
  3897. count = 0;
  3898. if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
  3899. p[count] == '@') {
  3900. p += count + 1;
  3901. } else {
  3902. align_order = -1;
  3903. }
  3904. if (sscanf(p, "%x:%x:%x.%x%n",
  3905. &seg, &bus, &slot, &func, &count) != 4) {
  3906. seg = 0;
  3907. if (sscanf(p, "%x:%x.%x%n",
  3908. &bus, &slot, &func, &count) != 3) {
  3909. /* Invalid format */
  3910. printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
  3911. p);
  3912. break;
  3913. }
  3914. }
  3915. p += count;
  3916. if (seg == pci_domain_nr(dev->bus) &&
  3917. bus == dev->bus->number &&
  3918. slot == PCI_SLOT(dev->devfn) &&
  3919. func == PCI_FUNC(dev->devfn)) {
  3920. if (align_order == -1)
  3921. align = PAGE_SIZE;
  3922. else
  3923. align = 1 << align_order;
  3924. /* Found */
  3925. break;
  3926. }
  3927. if (*p != ';' && *p != ',') {
  3928. /* End of param or invalid format */
  3929. break;
  3930. }
  3931. p++;
  3932. }
  3933. spin_unlock(&resource_alignment_lock);
  3934. return align;
  3935. }
  3936. /*
  3937. * This function disables memory decoding and releases memory resources
  3938. * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
  3939. * It also rounds up size to specified alignment.
  3940. * Later on, the kernel will assign page-aligned memory resource back
  3941. * to the device.
  3942. */
  3943. void pci_reassigndev_resource_alignment(struct pci_dev *dev)
  3944. {
  3945. int i;
  3946. struct resource *r;
  3947. resource_size_t align, size;
  3948. u16 command;
  3949. /* check if specified PCI is target device to reassign */
  3950. align = pci_specified_resource_alignment(dev);
  3951. if (!align)
  3952. return;
  3953. if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
  3954. (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
  3955. dev_warn(&dev->dev,
  3956. "Can't reassign resources to host bridge.\n");
  3957. return;
  3958. }
  3959. dev_info(&dev->dev,
  3960. "Disabling memory decoding and releasing memory resources.\n");
  3961. pci_read_config_word(dev, PCI_COMMAND, &command);
  3962. command &= ~PCI_COMMAND_MEMORY;
  3963. pci_write_config_word(dev, PCI_COMMAND, command);
  3964. for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
  3965. r = &dev->resource[i];
  3966. if (!(r->flags & IORESOURCE_MEM))
  3967. continue;
  3968. size = resource_size(r);
  3969. if (size < align) {
  3970. size = align;
  3971. dev_info(&dev->dev,
  3972. "Rounding up size of resource #%d to %#llx.\n",
  3973. i, (unsigned long long)size);
  3974. }
  3975. r->flags |= IORESOURCE_UNSET;
  3976. r->end = size - 1;
  3977. r->start = 0;
  3978. }
  3979. /* Need to disable bridge's resource window,
  3980. * to enable the kernel to reassign new resource
  3981. * window later on.
  3982. */
  3983. if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
  3984. (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
  3985. for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
  3986. r = &dev->resource[i];
  3987. if (!(r->flags & IORESOURCE_MEM))
  3988. continue;
  3989. r->flags |= IORESOURCE_UNSET;
  3990. r->end = resource_size(r) - 1;
  3991. r->start = 0;
  3992. }
  3993. pci_disable_bridge_window(dev);
  3994. }
  3995. }
  3996. static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
  3997. {
  3998. if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
  3999. count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
  4000. spin_lock(&resource_alignment_lock);
  4001. strncpy(resource_alignment_param, buf, count);
  4002. resource_alignment_param[count] = '\0';
  4003. spin_unlock(&resource_alignment_lock);
  4004. return count;
  4005. }
  4006. static ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
  4007. {
  4008. size_t count;
  4009. spin_lock(&resource_alignment_lock);
  4010. count = snprintf(buf, size, "%s", resource_alignment_param);
  4011. spin_unlock(&resource_alignment_lock);
  4012. return count;
  4013. }
  4014. static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
  4015. {
  4016. return pci_get_resource_alignment_param(buf, PAGE_SIZE);
  4017. }
  4018. static ssize_t pci_resource_alignment_store(struct bus_type *bus,
  4019. const char *buf, size_t count)
  4020. {
  4021. return pci_set_resource_alignment_param(buf, count);
  4022. }
  4023. BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
  4024. pci_resource_alignment_store);
  4025. static int __init pci_resource_alignment_sysfs_init(void)
  4026. {
  4027. return bus_create_file(&pci_bus_type,
  4028. &bus_attr_resource_alignment);
  4029. }
  4030. late_initcall(pci_resource_alignment_sysfs_init);
  4031. static void pci_no_domains(void)
  4032. {
  4033. #ifdef CONFIG_PCI_DOMAINS
  4034. pci_domains_supported = 0;
  4035. #endif
  4036. }
  4037. #ifdef CONFIG_PCI_DOMAINS
  4038. static atomic_t __domain_nr = ATOMIC_INIT(-1);
  4039. int pci_get_new_domain_nr(void)
  4040. {
  4041. return atomic_inc_return(&__domain_nr);
  4042. }
  4043. #ifdef CONFIG_PCI_DOMAINS_GENERIC
  4044. void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
  4045. {
  4046. static int use_dt_domains = -1;
  4047. int domain = -1;
  4048. if (parent)
  4049. domain = of_get_pci_domain_nr(parent->of_node);
  4050. /*
  4051. * Check DT domain and use_dt_domains values.
  4052. *
  4053. * If DT domain property is valid (domain >= 0) and
  4054. * use_dt_domains != 0, the DT assignment is valid since this means
  4055. * we have not previously allocated a domain number by using
  4056. * pci_get_new_domain_nr(); we should also update use_dt_domains to
  4057. * 1, to indicate that we have just assigned a domain number from
  4058. * DT.
  4059. *
  4060. * If DT domain property value is not valid (ie domain < 0), and we
  4061. * have not previously assigned a domain number from DT
  4062. * (use_dt_domains != 1) we should assign a domain number by
  4063. * using the:
  4064. *
  4065. * pci_get_new_domain_nr()
  4066. *
  4067. * API and update the use_dt_domains value to keep track of method we
  4068. * are using to assign domain numbers (use_dt_domains = 0).
  4069. *
  4070. * All other combinations imply we have a platform that is trying
  4071. * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
  4072. * which is a recipe for domain mishandling and it is prevented by
  4073. * invalidating the domain value (domain = -1) and printing a
  4074. * corresponding error.
  4075. */
  4076. if (domain >= 0 && use_dt_domains) {
  4077. use_dt_domains = 1;
  4078. } else if (domain < 0 && use_dt_domains != 1) {
  4079. use_dt_domains = 0;
  4080. domain = pci_get_new_domain_nr();
  4081. } else {
  4082. dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n",
  4083. parent->of_node->full_name);
  4084. domain = -1;
  4085. }
  4086. bus->domain_nr = domain;
  4087. }
  4088. #endif
  4089. #endif
  4090. /**
  4091. * pci_ext_cfg_avail - can we access extended PCI config space?
  4092. *
  4093. * Returns 1 if we can access PCI extended config space (offsets
  4094. * greater than 0xff). This is the default implementation. Architecture
  4095. * implementations can override this.
  4096. */
  4097. int __weak pci_ext_cfg_avail(void)
  4098. {
  4099. return 1;
  4100. }
  4101. void __weak pci_fixup_cardbus(struct pci_bus *bus)
  4102. {
  4103. }
  4104. EXPORT_SYMBOL(pci_fixup_cardbus);
  4105. static int __init pci_setup(char *str)
  4106. {
  4107. while (str) {
  4108. char *k = strchr(str, ',');
  4109. if (k)
  4110. *k++ = 0;
  4111. if (*str && (str = pcibios_setup(str)) && *str) {
  4112. if (!strcmp(str, "nomsi")) {
  4113. pci_no_msi();
  4114. } else if (!strcmp(str, "noaer")) {
  4115. pci_no_aer();
  4116. } else if (!strncmp(str, "realloc=", 8)) {
  4117. pci_realloc_get_opt(str + 8);
  4118. } else if (!strncmp(str, "realloc", 7)) {
  4119. pci_realloc_get_opt("on");
  4120. } else if (!strcmp(str, "nodomains")) {
  4121. pci_no_domains();
  4122. } else if (!strncmp(str, "noari", 5)) {
  4123. pcie_ari_disabled = true;
  4124. } else if (!strncmp(str, "cbiosize=", 9)) {
  4125. pci_cardbus_io_size = memparse(str + 9, &str);
  4126. } else if (!strncmp(str, "cbmemsize=", 10)) {
  4127. pci_cardbus_mem_size = memparse(str + 10, &str);
  4128. } else if (!strncmp(str, "resource_alignment=", 19)) {
  4129. pci_set_resource_alignment_param(str + 19,
  4130. strlen(str + 19));
  4131. } else if (!strncmp(str, "ecrc=", 5)) {
  4132. pcie_ecrc_get_policy(str + 5);
  4133. } else if (!strncmp(str, "hpiosize=", 9)) {
  4134. pci_hotplug_io_size = memparse(str + 9, &str);
  4135. } else if (!strncmp(str, "hpmemsize=", 10)) {
  4136. pci_hotplug_mem_size = memparse(str + 10, &str);
  4137. } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
  4138. pcie_bus_config = PCIE_BUS_TUNE_OFF;
  4139. } else if (!strncmp(str, "pcie_bus_safe", 13)) {
  4140. pcie_bus_config = PCIE_BUS_SAFE;
  4141. } else if (!strncmp(str, "pcie_bus_perf", 13)) {
  4142. pcie_bus_config = PCIE_BUS_PERFORMANCE;
  4143. } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
  4144. pcie_bus_config = PCIE_BUS_PEER2PEER;
  4145. } else if (!strncmp(str, "pcie_scan_all", 13)) {
  4146. pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
  4147. } else {
  4148. printk(KERN_ERR "PCI: Unknown option `%s'\n",
  4149. str);
  4150. }
  4151. }
  4152. str = k;
  4153. }
  4154. return 0;
  4155. }
  4156. early_param("pci", pci_setup);