/* * PCI Bus Services, see include/linux/pci.h for further explanation. * * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter, * David Mosberger-Tang * * Copyright 1997 -- 2000 Martin Mares */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pci.h" const char *pci_power_names[] = { "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown", }; EXPORT_SYMBOL_GPL(pci_power_names); int isa_dma_bridge_buggy; EXPORT_SYMBOL(isa_dma_bridge_buggy); int pci_pci_problems; EXPORT_SYMBOL(pci_pci_problems); unsigned int pci_pm_d3_delay; static void pci_pme_list_scan(struct work_struct *work); static LIST_HEAD(pci_pme_list); static DEFINE_MUTEX(pci_pme_list_mutex); static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan); struct pci_pme_device { struct list_head list; struct pci_dev *dev; }; #define PME_TIMEOUT 1000 /* How long between PME checks */ static void pci_dev_d3_sleep(struct pci_dev *dev) { unsigned int delay = dev->d3_delay; if (delay < pci_pm_d3_delay) delay = pci_pm_d3_delay; msleep(delay); } #ifdef CONFIG_PCI_DOMAINS int pci_domains_supported = 1; #endif #define DEFAULT_CARDBUS_IO_SIZE (256) #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024) /* pci=cbmemsize=nnM,cbiosize=nn can override this */ unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE; unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE; #define DEFAULT_HOTPLUG_IO_SIZE (256) #define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024) /* pci=hpmemsize=nnM,hpiosize=nn can override this */ unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE; unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE; enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF; /* * The default CLS is used if arch didn't set CLS explicitly and not * all pci devices agree on the same value. Arch can override either * the dfl or actual value as it sees fit. Don't forget this is * measured in 32-bit words, not bytes. */ u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2; u8 pci_cache_line_size; /* * If we set up a device for bus mastering, we need to check the latency * timer as certain BIOSes forget to set it properly. */ unsigned int pcibios_max_latency = 255; /* If set, the PCIe ARI capability will not be used. */ static bool pcie_ari_disabled; /** * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children * @bus: pointer to PCI bus structure to search * * Given a PCI bus, returns the highest PCI bus number present in the set * including the given PCI bus and its list of child PCI buses. */ unsigned char pci_bus_max_busnr(struct pci_bus* bus) { struct list_head *tmp; unsigned char max, n; max = bus->busn_res.end; list_for_each(tmp, &bus->children) { n = pci_bus_max_busnr(pci_bus_b(tmp)); if(n > max) max = n; } return max; } EXPORT_SYMBOL_GPL(pci_bus_max_busnr); #ifdef CONFIG_HAS_IOMEM void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar) { /* * Make sure the BAR is actually a memory resource, not an IO resource */ if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) { WARN_ON(1); return NULL; } return ioremap_nocache(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar)); } EXPORT_SYMBOL_GPL(pci_ioremap_bar); #endif #define PCI_FIND_CAP_TTL 48 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn, u8 pos, int cap, int *ttl) { u8 id; while ((*ttl)--) { pci_bus_read_config_byte(bus, devfn, pos, &pos); if (pos < 0x40) break; pos &= ~3; pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID, &id); if (id == 0xff) break; if (id == cap) return pos; pos += PCI_CAP_LIST_NEXT; } return 0; } static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn, u8 pos, int cap) { int ttl = PCI_FIND_CAP_TTL; return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl); } int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap) { return __pci_find_next_cap(dev->bus, dev->devfn, pos + PCI_CAP_LIST_NEXT, cap); } EXPORT_SYMBOL_GPL(pci_find_next_capability); static int __pci_bus_find_cap_start(struct pci_bus *bus, unsigned int devfn, u8 hdr_type) { u16 status; pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status); if (!(status & PCI_STATUS_CAP_LIST)) return 0; switch (hdr_type) { case PCI_HEADER_TYPE_NORMAL: case PCI_HEADER_TYPE_BRIDGE: return PCI_CAPABILITY_LIST; case PCI_HEADER_TYPE_CARDBUS: return PCI_CB_CAPABILITY_LIST; default: return 0; } return 0; } /** * pci_find_capability - query for devices' capabilities * @dev: PCI device to query * @cap: capability code * * Tell if a device supports a given PCI capability. * Returns the address of the requested capability structure within the * device's PCI configuration space or 0 in case the device does not * support it. Possible values for @cap: * * %PCI_CAP_ID_PM Power Management * %PCI_CAP_ID_AGP Accelerated Graphics Port * %PCI_CAP_ID_VPD Vital Product Data * %PCI_CAP_ID_SLOTID Slot Identification * %PCI_CAP_ID_MSI Message Signalled Interrupts * %PCI_CAP_ID_CHSWP CompactPCI HotSwap * %PCI_CAP_ID_PCIX PCI-X * %PCI_CAP_ID_EXP PCI Express */ int pci_find_capability(struct pci_dev *dev, int cap) { int pos; pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type); if (pos) pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap); return pos; } /** * pci_bus_find_capability - query for devices' capabilities * @bus: the PCI bus to query * @devfn: PCI device to query * @cap: capability code * * Like pci_find_capability() but works for pci devices that do not have a * pci_dev structure set up yet. * * Returns the address of the requested capability structure within the * device's PCI configuration space or 0 in case the device does not * support it. */ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap) { int pos; u8 hdr_type; pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type); pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f); if (pos) pos = __pci_find_next_cap(bus, devfn, pos, cap); return pos; } /** * pci_find_next_ext_capability - Find an extended capability * @dev: PCI device to query * @start: address at which to start looking (0 to start at beginning of list) * @cap: capability code * * Returns the address of the next matching extended capability structure * within the device's PCI configuration space or 0 if the device does * not support it. Some capabilities can occur several times, e.g., the * vendor-specific capability, and this provides a way to find them all. */ int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap) { u32 header; int ttl; int pos = PCI_CFG_SPACE_SIZE; /* minimum 8 bytes per capability */ ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8; if (dev->cfg_size <= PCI_CFG_SPACE_SIZE) return 0; if (start) pos = start; if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL) return 0; /* * If we have no capabilities, this is indicated by cap ID, * cap version and next pointer all being 0. */ if (header == 0) return 0; while (ttl-- > 0) { if (PCI_EXT_CAP_ID(header) == cap && pos != start) return pos; pos = PCI_EXT_CAP_NEXT(header); if (pos < PCI_CFG_SPACE_SIZE) break; if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL) break; } return 0; } EXPORT_SYMBOL_GPL(pci_find_next_ext_capability); /** * pci_find_ext_capability - Find an extended capability * @dev: PCI device to query * @cap: capability code * * Returns the address of the requested extended capability structure * within the device's PCI configuration space or 0 if the device does * not support it. Possible values for @cap: * * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting * %PCI_EXT_CAP_ID_VC Virtual Channel * %PCI_EXT_CAP_ID_DSN Device Serial Number * %PCI_EXT_CAP_ID_PWR Power Budgeting */ int pci_find_ext_capability(struct pci_dev *dev, int cap) { return pci_find_next_ext_capability(dev, 0, cap); } EXPORT_SYMBOL_GPL(pci_find_ext_capability); static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap) { int rc, ttl = PCI_FIND_CAP_TTL; u8 cap, mask; if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST) mask = HT_3BIT_CAP_MASK; else mask = HT_5BIT_CAP_MASK; pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos, PCI_CAP_ID_HT, &ttl); while (pos) { rc = pci_read_config_byte(dev, pos + 3, &cap); if (rc != PCIBIOS_SUCCESSFUL) return 0; if ((cap & mask) == ht_cap) return pos; pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos + PCI_CAP_LIST_NEXT, PCI_CAP_ID_HT, &ttl); } return 0; } /** * pci_find_next_ht_capability - query a device's Hypertransport capabilities * @dev: PCI device to query * @pos: Position from which to continue searching * @ht_cap: Hypertransport capability code * * To be used in conjunction with pci_find_ht_capability() to search for * all capabilities matching @ht_cap. @pos should always be a value returned * from pci_find_ht_capability(). * * NB. To be 100% safe against broken PCI devices, the caller should take * steps to avoid an infinite loop. */ int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap) { return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap); } EXPORT_SYMBOL_GPL(pci_find_next_ht_capability); /** * pci_find_ht_capability - query a device's Hypertransport capabilities * @dev: PCI device to query * @ht_cap: Hypertransport capability code * * Tell if a device supports a given Hypertransport capability. * Returns an address within the device's PCI configuration space * or 0 in case the device does not support the request capability. * The address points to the PCI capability, of type PCI_CAP_ID_HT, * which has a Hypertransport capability matching @ht_cap. */ int pci_find_ht_capability(struct pci_dev *dev, int ht_cap) { int pos; pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type); if (pos) pos = __pci_find_next_ht_cap(dev, pos, ht_cap); return pos; } EXPORT_SYMBOL_GPL(pci_find_ht_capability); /** * pci_find_parent_resource - return resource region of parent bus of given region * @dev: PCI device structure contains resources to be searched * @res: child resource record for which parent is sought * * For given resource region of given device, return the resource * region of parent bus the given region is contained in or where * it should be allocated from. */ struct resource * pci_find_parent_resource(const struct pci_dev *dev, struct resource *res) { const struct pci_bus *bus = dev->bus; int i; struct resource *best = NULL, *r; pci_bus_for_each_resource(bus, r, i) { if (!r) continue; if (res->start && !(res->start >= r->start && res->end <= r->end)) continue; /* Not contained */ if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM)) continue; /* Wrong type */ if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH)) return r; /* Exact match */ /* We can't insert a non-prefetch resource inside a prefetchable parent .. */ if (r->flags & IORESOURCE_PREFETCH) continue; /* .. but we can put a prefetchable resource inside a non-prefetchable one */ if (!best) best = r; } return best; } /** * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos * @dev: the PCI device to operate on * @pos: config space offset of status word * @mask: mask of bit(s) to care about in status word * * Return 1 when mask bit(s) in status word clear, 0 otherwise. */ int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask) { int i; /* Wait for Transaction Pending bit clean */ for (i = 0; i < 4; i++) { u16 status; if (i) msleep((1 << (i - 1)) * 100); pci_read_config_word(dev, pos, &status); if (!(status & mask)) return 1; } return 0; } /** * pci_restore_bars - restore a devices BAR values (e.g. after wake-up) * @dev: PCI device to have its BARs restored * * Restore the BAR values for a given device, so as to make it * accessible by its driver. */ static void pci_restore_bars(struct pci_dev *dev) { int i; for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) pci_update_resource(dev, i); } static struct pci_platform_pm_ops *pci_platform_pm; int pci_set_platform_pm(struct pci_platform_pm_ops *ops) { if (!ops->is_manageable || !ops->set_state || !ops->choose_state || !ops->sleep_wake) return -EINVAL; pci_platform_pm = ops; return 0; } static inline bool platform_pci_power_manageable(struct pci_dev *dev) { return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false; } static inline int platform_pci_set_power_state(struct pci_dev *dev, pci_power_t t) { return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS; } static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev) { return pci_platform_pm ? pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR; } static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable) { return pci_platform_pm ? pci_platform_pm->sleep_wake(dev, enable) : -ENODEV; } static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable) { return pci_platform_pm ? pci_platform_pm->run_wake(dev, enable) : -ENODEV; } /** * pci_raw_set_power_state - Use PCI PM registers to set the power state of * given PCI device * @dev: PCI device to handle. * @state: PCI power state (D0, D1, D2, D3hot) to put the device into. * * RETURN VALUE: * -EINVAL if the requested state is invalid. * -EIO if device does not support PCI PM or its PM capabilities register has a * wrong version, or device doesn't support the requested state. * 0 if device already is in the requested state. * 0 if device's power state has been successfully changed. */ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state) { u16 pmcsr; bool need_restore = false; /* Check if we're already there */ if (dev->current_state == state) return 0; if (!dev->pm_cap) return -EIO; if (state < PCI_D0 || state > PCI_D3hot) return -EINVAL; /* Validate current state: * Can enter D0 from any state, but if we can only go deeper * to sleep if we're already in a low power state */ if (state != PCI_D0 && dev->current_state <= PCI_D3cold && dev->current_state > state) { dev_err(&dev->dev, "invalid power transition " "(from state %d to %d)\n", dev->current_state, state); return -EINVAL; } /* check if this device supports the desired state */ if ((state == PCI_D1 && !dev->d1_support) || (state == PCI_D2 && !dev->d2_support)) return -EIO; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); /* If we're (effectively) in D3, force entire word to 0. * This doesn't affect PME_Status, disables PME_En, and * sets PowerState to 0. */ switch (dev->current_state) { case PCI_D0: case PCI_D1: case PCI_D2: pmcsr &= ~PCI_PM_CTRL_STATE_MASK; pmcsr |= state; break; case PCI_D3hot: case PCI_D3cold: case PCI_UNKNOWN: /* Boot-up */ if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET)) need_restore = true; /* Fall-through: force to D0 */ default: pmcsr = 0; break; } /* enter specified state */ pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr); /* Mandatory power management transition delays */ /* see PCI PM 1.1 5.6.1 table 18 */ if (state == PCI_D3hot || dev->current_state == PCI_D3hot) pci_dev_d3_sleep(dev); else if (state == PCI_D2 || dev->current_state == PCI_D2) udelay(PCI_PM_D2_DELAY); pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK); if (dev->current_state != state && printk_ratelimit()) dev_info(&dev->dev, "Refused to change power state, " "currently in D%d\n", dev->current_state); /* * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning * from D3hot to D0 _may_ perform an internal reset, thereby * going to "D0 Uninitialized" rather than "D0 Initialized". * For example, at least some versions of the 3c905B and the * 3c556B exhibit this behaviour. * * At least some laptop BIOSen (e.g. the Thinkpad T21) leave * devices in a D3hot state at boot. Consequently, we need to * restore at least the BARs so that the device will be * accessible to its driver. */ if (need_restore) pci_restore_bars(dev); if (dev->bus->self) pcie_aspm_pm_state_change(dev->bus->self); return 0; } /** * pci_update_current_state - Read PCI power state of given device from its * PCI PM registers and cache it * @dev: PCI device to handle. * @state: State to cache in case the device doesn't have the PM capability */ void pci_update_current_state(struct pci_dev *dev, pci_power_t state) { if (dev->pm_cap) { u16 pmcsr; /* * Configuration space is not accessible for device in * D3cold, so just keep or set D3cold for safety */ if (dev->current_state == PCI_D3cold) return; if (state == PCI_D3cold) { dev->current_state = PCI_D3cold; return; } pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK); } else { dev->current_state = state; } } /** * pci_power_up - Put the given device into D0 forcibly * @dev: PCI device to power up */ void pci_power_up(struct pci_dev *dev) { if (platform_pci_power_manageable(dev)) platform_pci_set_power_state(dev, PCI_D0); pci_raw_set_power_state(dev, PCI_D0); pci_update_current_state(dev, PCI_D0); } /** * pci_platform_power_transition - Use platform to change device power state * @dev: PCI device to handle. * @state: State to put the device into. */ static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state) { int error; if (platform_pci_power_manageable(dev)) { error = platform_pci_set_power_state(dev, state); if (!error) pci_update_current_state(dev, state); } else error = -ENODEV; if (error && !dev->pm_cap) /* Fall back to PCI_D0 */ dev->current_state = PCI_D0; return error; } /** * pci_wakeup - Wake up a PCI device * @pci_dev: Device to handle. * @ign: ignored parameter */ static int pci_wakeup(struct pci_dev *pci_dev, void *ign) { pci_wakeup_event(pci_dev); pm_request_resume(&pci_dev->dev); return 0; } /** * pci_wakeup_bus - Walk given bus and wake up devices on it * @bus: Top bus of the subtree to walk. */ static void pci_wakeup_bus(struct pci_bus *bus) { if (bus) pci_walk_bus(bus, pci_wakeup, NULL); } /** * __pci_start_power_transition - Start power transition of a PCI device * @dev: PCI device to handle. * @state: State to put the device into. */ static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state) { if (state == PCI_D0) { pci_platform_power_transition(dev, PCI_D0); /* * Mandatory power management transition delays, see * PCI Express Base Specification Revision 2.0 Section * 6.6.1: Conventional Reset. Do not delay for * devices powered on/off by corresponding bridge, * because have already delayed for the bridge. */ if (dev->runtime_d3cold) { msleep(dev->d3cold_delay); /* * When powering on a bridge from D3cold, the * whole hierarchy may be powered on into * D0uninitialized state, resume them to give * them a chance to suspend again */ pci_wakeup_bus(dev->subordinate); } } } /** * __pci_dev_set_current_state - Set current state of a PCI device * @dev: Device to handle * @data: pointer to state to be set */ static int __pci_dev_set_current_state(struct pci_dev *dev, void *data) { pci_power_t state = *(pci_power_t *)data; dev->current_state = state; return 0; } /** * __pci_bus_set_current_state - Walk given bus and set current state of devices * @bus: Top bus of the subtree to walk. * @state: state to be set */ static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state) { if (bus) pci_walk_bus(bus, __pci_dev_set_current_state, &state); } /** * __pci_complete_power_transition - Complete power transition of a PCI device * @dev: PCI device to handle. * @state: State to put the device into. * * This function should not be called directly by device drivers. */ int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state) { int ret; if (state <= PCI_D0) return -EINVAL; ret = pci_platform_power_transition(dev, state); /* Power off the bridge may power off the whole hierarchy */ if (!ret && state == PCI_D3cold) __pci_bus_set_current_state(dev->subordinate, PCI_D3cold); return ret; } EXPORT_SYMBOL_GPL(__pci_complete_power_transition); /** * pci_set_power_state - Set the power state of a PCI device * @dev: PCI device to handle. * @state: PCI power state (D0, D1, D2, D3hot) to put the device into. * * Transition a device to a new power state, using the platform firmware and/or * the device's PCI PM registers. * * RETURN VALUE: * -EINVAL if the requested state is invalid. * -EIO if device does not support PCI PM or its PM capabilities register has a * wrong version, or device doesn't support the requested state. * 0 if device already is in the requested state. * 0 if device's power state has been successfully changed. */ int pci_set_power_state(struct pci_dev *dev, pci_power_t state) { int error; /* bound the state we're entering */ if (state > PCI_D3cold) state = PCI_D3cold; else if (state < PCI_D0) state = PCI_D0; else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev)) /* * If the device or the parent bridge do not support PCI PM, * ignore the request if we're doing anything other than putting * it into D0 (which would only happen on boot). */ return 0; /* Check if we're already there */ if (dev->current_state == state) return 0; __pci_start_power_transition(dev, state); /* This device is quirked not to be put into D3, so don't put it in D3 */ if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3)) return 0; /* * To put device in D3cold, we put device into D3hot in native * way, then put device into D3cold with platform ops */ error = pci_raw_set_power_state(dev, state > PCI_D3hot ? PCI_D3hot : state); if (!__pci_complete_power_transition(dev, state)) error = 0; /* * When aspm_policy is "powersave" this call ensures * that ASPM is configured. */ if (!error && dev->bus->self) pcie_aspm_powersave_config_link(dev->bus->self); return error; } /** * pci_choose_state - Choose the power state of a PCI device * @dev: PCI device to be suspended * @state: target sleep state for the whole system. This is the value * that is passed to suspend() function. * * Returns PCI power state suitable for given device and given system * message. */ pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state) { pci_power_t ret; if (!dev->pm_cap) return PCI_D0; ret = platform_pci_choose_state(dev); if (ret != PCI_POWER_ERROR) return ret; switch (state.event) { case PM_EVENT_ON: return PCI_D0; case PM_EVENT_FREEZE: case PM_EVENT_PRETHAW: /* REVISIT both freeze and pre-thaw "should" use D0 */ case PM_EVENT_SUSPEND: case PM_EVENT_HIBERNATE: return PCI_D3hot; default: dev_info(&dev->dev, "unrecognized suspend event %d\n", state.event); BUG(); } return PCI_D0; } EXPORT_SYMBOL(pci_choose_state); #define PCI_EXP_SAVE_REGS 7 static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev, u16 cap, bool extended) { struct pci_cap_saved_state *tmp; hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) { if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap) return tmp; } return NULL; } struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap) { return _pci_find_saved_cap(dev, cap, false); } struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap) { return _pci_find_saved_cap(dev, cap, true); } static int pci_save_pcie_state(struct pci_dev *dev) { int i = 0; struct pci_cap_saved_state *save_state; u16 *cap; if (!pci_is_pcie(dev)) return 0; save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP); if (!save_state) { dev_err(&dev->dev, "buffer not found in %s\n", __func__); return -ENOMEM; } cap = (u16 *)&save_state->cap.data[0]; pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_RTCTL, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]); pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]); return 0; } static void pci_restore_pcie_state(struct pci_dev *dev) { int i = 0; struct pci_cap_saved_state *save_state; u16 *cap; save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP); if (!save_state) return; cap = (u16 *)&save_state->cap.data[0]; pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]); } static int pci_save_pcix_state(struct pci_dev *dev) { int pos; struct pci_cap_saved_state *save_state; pos = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (pos <= 0) return 0; save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX); if (!save_state) { dev_err(&dev->dev, "buffer not found in %s\n", __func__); return -ENOMEM; } pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->cap.data); return 0; } static void pci_restore_pcix_state(struct pci_dev *dev) { int i = 0, pos; struct pci_cap_saved_state *save_state; u16 *cap; save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX); pos = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (!save_state || pos <= 0) return; cap = (u16 *)&save_state->cap.data[0]; pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]); } /** * pci_save_state - save the PCI configuration space of a device before suspending * @dev: - PCI device that we're dealing with */ int pci_save_state(struct pci_dev *dev) { int i; /* XXX: 100% dword access ok here? */ for (i = 0; i < 16; i++) pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]); dev->state_saved = true; if ((i = pci_save_pcie_state(dev)) != 0) return i; if ((i = pci_save_pcix_state(dev)) != 0) return i; if ((i = pci_save_vc_state(dev)) != 0) return i; return 0; } static void pci_restore_config_dword(struct pci_dev *pdev, int offset, u32 saved_val, int retry) { u32 val; pci_read_config_dword(pdev, offset, &val); if (val == saved_val) return; for (;;) { dev_dbg(&pdev->dev, "restoring config space at offset " "%#x (was %#x, writing %#x)\n", offset, val, saved_val); pci_write_config_dword(pdev, offset, saved_val); if (retry-- <= 0) return; pci_read_config_dword(pdev, offset, &val); if (val == saved_val) return; mdelay(1); } } static void pci_restore_config_space_range(struct pci_dev *pdev, int start, int end, int retry) { int index; for (index = end; index >= start; index--) pci_restore_config_dword(pdev, 4 * index, pdev->saved_config_space[index], retry); } static void pci_restore_config_space(struct pci_dev *pdev) { if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) { pci_restore_config_space_range(pdev, 10, 15, 0); /* Restore BARs before the command register. */ pci_restore_config_space_range(pdev, 4, 9, 10); pci_restore_config_space_range(pdev, 0, 3, 0); } else { pci_restore_config_space_range(pdev, 0, 15, 0); } } /** * pci_restore_state - Restore the saved state of a PCI device * @dev: - PCI device that we're dealing with */ void pci_restore_state(struct pci_dev *dev) { if (!dev->state_saved) return; /* PCI Express register must be restored first */ pci_restore_pcie_state(dev); pci_restore_ats_state(dev); pci_restore_vc_state(dev); pci_restore_config_space(dev); pci_restore_pcix_state(dev); pci_restore_msi_state(dev); pci_restore_iov_state(dev); dev->state_saved = false; } struct pci_saved_state { u32 config_space[16]; struct pci_cap_saved_data cap[0]; }; /** * pci_store_saved_state - Allocate and return an opaque struct containing * the device saved state. * @dev: PCI device that we're dealing with * * Return NULL if no state or error. */ struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev) { struct pci_saved_state *state; struct pci_cap_saved_state *tmp; struct pci_cap_saved_data *cap; size_t size; if (!dev->state_saved) return NULL; size = sizeof(*state) + sizeof(struct pci_cap_saved_data); hlist_for_each_entry(tmp, &dev->saved_cap_space, next) size += sizeof(struct pci_cap_saved_data) + tmp->cap.size; state = kzalloc(size, GFP_KERNEL); if (!state) return NULL; memcpy(state->config_space, dev->saved_config_space, sizeof(state->config_space)); cap = state->cap; hlist_for_each_entry(tmp, &dev->saved_cap_space, next) { size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size; memcpy(cap, &tmp->cap, len); cap = (struct pci_cap_saved_data *)((u8 *)cap + len); } /* Empty cap_save terminates list */ return state; } EXPORT_SYMBOL_GPL(pci_store_saved_state); /** * pci_load_saved_state - Reload the provided save state into struct pci_dev. * @dev: PCI device that we're dealing with * @state: Saved state returned from pci_store_saved_state() */ static int pci_load_saved_state(struct pci_dev *dev, struct pci_saved_state *state) { struct pci_cap_saved_data *cap; dev->state_saved = false; if (!state) return 0; memcpy(dev->saved_config_space, state->config_space, sizeof(state->config_space)); cap = state->cap; while (cap->size) { struct pci_cap_saved_state *tmp; tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended); if (!tmp || tmp->cap.size != cap->size) return -EINVAL; memcpy(tmp->cap.data, cap->data, tmp->cap.size); cap = (struct pci_cap_saved_data *)((u8 *)cap + sizeof(struct pci_cap_saved_data) + cap->size); } dev->state_saved = true; return 0; } /** * pci_load_and_free_saved_state - Reload the save state pointed to by state, * and free the memory allocated for it. * @dev: PCI device that we're dealing with * @state: Pointer to saved state returned from pci_store_saved_state() */ int pci_load_and_free_saved_state(struct pci_dev *dev, struct pci_saved_state **state) { int ret = pci_load_saved_state(dev, *state); kfree(*state); *state = NULL; return ret; } EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state); static int do_pci_enable_device(struct pci_dev *dev, int bars) { int err; err = pci_set_power_state(dev, PCI_D0); if (err < 0 && err != -EIO) return err; err = pcibios_enable_device(dev, bars); if (err < 0) return err; pci_fixup_device(pci_fixup_enable, dev); return 0; } /** * pci_reenable_device - Resume abandoned device * @dev: PCI device to be resumed * * Note this function is a backend of pci_default_resume and is not supposed * to be called by normal code, write proper resume handler and use it instead. */ int pci_reenable_device(struct pci_dev *dev) { if (pci_is_enabled(dev)) return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1); return 0; } static void pci_enable_bridge(struct pci_dev *dev) { struct pci_dev *bridge; int retval; bridge = pci_upstream_bridge(dev); if (bridge) pci_enable_bridge(bridge); if (pci_is_enabled(dev)) { if (!dev->is_busmaster) pci_set_master(dev); return; } retval = pci_enable_device(dev); if (retval) dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval); pci_set_master(dev); } static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) { struct pci_dev *bridge; int err; int i, bars = 0; /* * Power state could be unknown at this point, either due to a fresh * boot or a device removal call. So get the current power state * so that things like MSI message writing will behave as expected * (e.g. if the device really is in D0 at enable time). */ if (dev->pm_cap) { u16 pmcsr; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK); } if (atomic_inc_return(&dev->enable_cnt) > 1) return 0; /* already enabled */ bridge = pci_upstream_bridge(dev); if (bridge) pci_enable_bridge(bridge); /* only skip sriov related */ for (i = 0; i <= PCI_ROM_RESOURCE; i++) if (dev->resource[i].flags & flags) bars |= (1 << i); for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++) if (dev->resource[i].flags & flags) bars |= (1 << i); err = do_pci_enable_device(dev, bars); if (err < 0) atomic_dec(&dev->enable_cnt); return err; } /** * pci_enable_device_io - Initialize a device for use with IO space * @dev: PCI device to be initialized * * Initialize device before it's used by a driver. Ask low-level code * to enable I/O resources. Wake up the device if it was suspended. * Beware, this function can fail. */ int pci_enable_device_io(struct pci_dev *dev) { return pci_enable_device_flags(dev, IORESOURCE_IO); } /** * pci_enable_device_mem - Initialize a device for use with Memory space * @dev: PCI device to be initialized * * Initialize device before it's used by a driver. Ask low-level code * to enable Memory resources. Wake up the device if it was suspended. * Beware, this function can fail. */ int pci_enable_device_mem(struct pci_dev *dev) { return pci_enable_device_flags(dev, IORESOURCE_MEM); } /** * pci_enable_device - Initialize device before it's used by a driver. * @dev: PCI device to be initialized * * Initialize device before it's used by a driver. Ask low-level code * to enable I/O and memory. Wake up the device if it was suspended. * Beware, this function can fail. * * Note we don't actually enable the device many times if we call * this function repeatedly (we just increment the count). */ int pci_enable_device(struct pci_dev *dev) { return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO); } /* * Managed PCI resources. This manages device on/off, intx/msi/msix * on/off and BAR regions. pci_dev itself records msi/msix status, so * there's no need to track it separately. pci_devres is initialized * when a device is enabled using managed PCI device enable interface. */ struct pci_devres { unsigned int enabled:1; unsigned int pinned:1; unsigned int orig_intx:1; unsigned int restore_intx:1; u32 region_mask; }; static void pcim_release(struct device *gendev, void *res) { struct pci_dev *dev = container_of(gendev, struct pci_dev, dev); struct pci_devres *this = res; int i; if (dev->msi_enabled) pci_disable_msi(dev); if (dev->msix_enabled) pci_disable_msix(dev); for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) if (this->region_mask & (1 << i)) pci_release_region(dev, i); if (this->restore_intx) pci_intx(dev, this->orig_intx); if (this->enabled && !this->pinned) pci_disable_device(dev); } static struct pci_devres * get_pci_dr(struct pci_dev *pdev) { struct pci_devres *dr, *new_dr; dr = devres_find(&pdev->dev, pcim_release, NULL, NULL); if (dr) return dr; new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL); if (!new_dr) return NULL; return devres_get(&pdev->dev, new_dr, NULL, NULL); } static struct pci_devres * find_pci_dr(struct pci_dev *pdev) { if (pci_is_managed(pdev)) return devres_find(&pdev->dev, pcim_release, NULL, NULL); return NULL; } /** * pcim_enable_device - Managed pci_enable_device() * @pdev: PCI device to be initialized * * Managed pci_enable_device(). */ int pcim_enable_device(struct pci_dev *pdev) { struct pci_devres *dr; int rc; dr = get_pci_dr(pdev); if (unlikely(!dr)) return -ENOMEM; if (dr->enabled) return 0; rc = pci_enable_device(pdev); if (!rc) { pdev->is_managed = 1; dr->enabled = 1; } return rc; } /** * pcim_pin_device - Pin managed PCI device * @pdev: PCI device to pin * * Pin managed PCI device @pdev. Pinned device won't be disabled on * driver detach. @pdev must have been enabled with * pcim_enable_device(). */ void pcim_pin_device(struct pci_dev *pdev) { struct pci_devres *dr; dr = find_pci_dr(pdev); WARN_ON(!dr || !dr->enabled); if (dr) dr->pinned = 1; } /* * pcibios_add_device - provide arch specific hooks when adding device dev * @dev: the PCI device being added * * Permits the platform to provide architecture specific functionality when * devices are added. This is the default implementation. Architecture * implementations can override this. */ int __weak pcibios_add_device (struct pci_dev *dev) { return 0; } /** * pcibios_release_device - provide arch specific hooks when releasing device dev * @dev: the PCI device being released * * Permits the platform to provide architecture specific functionality when * devices are released. This is the default implementation. Architecture * implementations can override this. */ void __weak pcibios_release_device(struct pci_dev *dev) {} /** * pcibios_disable_device - disable arch specific PCI resources for device dev * @dev: the PCI device to disable * * Disables architecture specific PCI resources for the device. This * is the default implementation. Architecture implementations can * override this. */ void __weak pcibios_disable_device (struct pci_dev *dev) {} static void do_pci_disable_device(struct pci_dev *dev) { u16 pci_command; pci_read_config_word(dev, PCI_COMMAND, &pci_command); if (pci_command & PCI_COMMAND_MASTER) { pci_command &= ~PCI_COMMAND_MASTER; pci_write_config_word(dev, PCI_COMMAND, pci_command); } pcibios_disable_device(dev); } /** * pci_disable_enabled_device - Disable device without updating enable_cnt * @dev: PCI device to disable * * NOTE: This function is a backend of PCI power management routines and is * not supposed to be called drivers. */ void pci_disable_enabled_device(struct pci_dev *dev) { if (pci_is_enabled(dev)) do_pci_disable_device(dev); } /** * pci_disable_device - Disable PCI device after use * @dev: PCI device to be disabled * * Signal to the system that the PCI device is not in use by the system * anymore. This only involves disabling PCI bus-mastering, if active. * * Note we don't actually disable the device until all callers of * pci_enable_device() have called pci_disable_device(). */ void pci_disable_device(struct pci_dev *dev) { struct pci_devres *dr; dr = find_pci_dr(dev); if (dr) dr->enabled = 0; dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0, "disabling already-disabled device"); if (atomic_dec_return(&dev->enable_cnt) != 0) return; do_pci_disable_device(dev); dev->is_busmaster = 0; } /** * pcibios_set_pcie_reset_state - set reset state for device dev * @dev: the PCIe device reset * @state: Reset state to enter into * * * Sets the PCIe reset state for the device. This is the default * implementation. Architecture implementations can override this. */ int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state) { return -EINVAL; } /** * pci_set_pcie_reset_state - set reset state for device dev * @dev: the PCIe device reset * @state: Reset state to enter into * * * Sets the PCI reset state for the device. */ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state) { return pcibios_set_pcie_reset_state(dev, state); } /** * pci_check_pme_status - Check if given device has generated PME. * @dev: Device to check. * * Check the PME status of the device and if set, clear it and clear PME enable * (if set). Return 'true' if PME status and PME enable were both set or * 'false' otherwise. */ bool pci_check_pme_status(struct pci_dev *dev) { int pmcsr_pos; u16 pmcsr; bool ret = false; if (!dev->pm_cap) return false; pmcsr_pos = dev->pm_cap + PCI_PM_CTRL; pci_read_config_word(dev, pmcsr_pos, &pmcsr); if (!(pmcsr & PCI_PM_CTRL_PME_STATUS)) return false; /* Clear PME status. */ pmcsr |= PCI_PM_CTRL_PME_STATUS; if (pmcsr & PCI_PM_CTRL_PME_ENABLE) { /* Disable PME to avoid interrupt flood. */ pmcsr &= ~PCI_PM_CTRL_PME_ENABLE; ret = true; } pci_write_config_word(dev, pmcsr_pos, pmcsr); return ret; } /** * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set. * @dev: Device to handle. * @pme_poll_reset: Whether or not to reset the device's pme_poll flag. * * Check if @dev has generated PME and queue a resume request for it in that * case. */ static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset) { if (pme_poll_reset && dev->pme_poll) dev->pme_poll = false; if (pci_check_pme_status(dev)) { pci_wakeup_event(dev); pm_request_resume(&dev->dev); } return 0; } /** * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary. * @bus: Top bus of the subtree to walk. */ void pci_pme_wakeup_bus(struct pci_bus *bus) { if (bus) pci_walk_bus(bus, pci_pme_wakeup, (void *)true); } /** * pci_pme_capable - check the capability of PCI device to generate PME# * @dev: PCI device to handle. * @state: PCI state from which device will issue PME#. */ bool pci_pme_capable(struct pci_dev *dev, pci_power_t state) { if (!dev->pm_cap) return false; return !!(dev->pme_support & (1 << state)); } static void pci_pme_list_scan(struct work_struct *work) { struct pci_pme_device *pme_dev, *n; mutex_lock(&pci_pme_list_mutex); if (!list_empty(&pci_pme_list)) { list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) { if (pme_dev->dev->pme_poll) { struct pci_dev *bridge; bridge = pme_dev->dev->bus->self; /* * If bridge is in low power state, the * configuration space of subordinate devices * may be not accessible */ if (bridge && bridge->current_state != PCI_D0) continue; pci_pme_wakeup(pme_dev->dev, NULL); } else { list_del(&pme_dev->list); kfree(pme_dev); } } if (!list_empty(&pci_pme_list)) schedule_delayed_work(&pci_pme_work, msecs_to_jiffies(PME_TIMEOUT)); } mutex_unlock(&pci_pme_list_mutex); } /** * pci_pme_active - enable or disable PCI device's PME# function * @dev: PCI device to handle. * @enable: 'true' to enable PME# generation; 'false' to disable it. * * The caller must verify that the device is capable of generating PME# before * calling this function with @enable equal to 'true'. */ void pci_pme_active(struct pci_dev *dev, bool enable) { u16 pmcsr; if (!dev->pme_support) return; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); /* Clear PME_Status by writing 1 to it and enable PME# */ pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE; if (!enable) pmcsr &= ~PCI_PM_CTRL_PME_ENABLE; pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr); /* * PCI (as opposed to PCIe) PME requires that the device have * its PME# line hooked up correctly. Not all hardware vendors * do this, so the PME never gets delivered and the device * remains asleep. The easiest way around this is to * periodically walk the list of suspended devices and check * whether any have their PME flag set. The assumption is that * we'll wake up often enough anyway that this won't be a huge * hit, and the power savings from the devices will still be a * win. * * Although PCIe uses in-band PME message instead of PME# line * to report PME, PME does not work for some PCIe devices in * reality. For example, there are devices that set their PME * status bits, but don't really bother to send a PME message; * there are PCI Express Root Ports that don't bother to * trigger interrupts when they receive PME messages from the * devices below. So PME poll is used for PCIe devices too. */ if (dev->pme_poll) { struct pci_pme_device *pme_dev; if (enable) { pme_dev = kmalloc(sizeof(struct pci_pme_device), GFP_KERNEL); if (!pme_dev) { dev_warn(&dev->dev, "can't enable PME#\n"); return; } pme_dev->dev = dev; mutex_lock(&pci_pme_list_mutex); list_add(&pme_dev->list, &pci_pme_list); if (list_is_singular(&pci_pme_list)) schedule_delayed_work(&pci_pme_work, msecs_to_jiffies(PME_TIMEOUT)); mutex_unlock(&pci_pme_list_mutex); } else { mutex_lock(&pci_pme_list_mutex); list_for_each_entry(pme_dev, &pci_pme_list, list) { if (pme_dev->dev == dev) { list_del(&pme_dev->list); kfree(pme_dev); break; } } mutex_unlock(&pci_pme_list_mutex); } } dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled"); } /** * __pci_enable_wake - enable PCI device as wakeup event source * @dev: PCI device affected * @state: PCI state from which device will issue wakeup events * @runtime: True if the events are to be generated at run time * @enable: True to enable event generation; false to disable * * This enables the device as a wakeup event source, or disables it. * When such events involves platform-specific hooks, those hooks are * called automatically by this routine. * * Devices with legacy power management (no standard PCI PM capabilities) * always require such platform hooks. * * RETURN VALUE: * 0 is returned on success * -EINVAL is returned if device is not supposed to wake up the system * Error code depending on the platform is returned if both the platform and * the native mechanism fail to enable the generation of wake-up events */ int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool runtime, bool enable) { int ret = 0; if (enable && !runtime && !device_may_wakeup(&dev->dev)) return -EINVAL; /* Don't do the same thing twice in a row for one device. */ if (!!enable == !!dev->wakeup_prepared) return 0; /* * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don * Anderson we should be doing PME# wake enable followed by ACPI wake * enable. To disable wake-up we call the platform first, for symmetry. */ if (enable) { int error; if (pci_pme_capable(dev, state)) pci_pme_active(dev, true); else ret = 1; error = runtime ? platform_pci_run_wake(dev, true) : platform_pci_sleep_wake(dev, true); if (ret) ret = error; if (!ret) dev->wakeup_prepared = true; } else { if (runtime) platform_pci_run_wake(dev, false); else platform_pci_sleep_wake(dev, false); pci_pme_active(dev, false); dev->wakeup_prepared = false; } return ret; } EXPORT_SYMBOL(__pci_enable_wake); /** * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold * @dev: PCI device to prepare * @enable: True to enable wake-up event generation; false to disable * * Many drivers want the device to wake up the system from D3_hot or D3_cold * and this function allows them to set that up cleanly - pci_enable_wake() * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI * ordering constraints. * * This function only returns error code if the device is not capable of * generating PME# from both D3_hot and D3_cold, and the platform is unable to * enable wake-up power for it. */ int pci_wake_from_d3(struct pci_dev *dev, bool enable) { return pci_pme_capable(dev, PCI_D3cold) ? pci_enable_wake(dev, PCI_D3cold, enable) : pci_enable_wake(dev, PCI_D3hot, enable); } /** * pci_target_state - find an appropriate low power state for a given PCI dev * @dev: PCI device * * Use underlying platform code to find a supported low power state for @dev. * If the platform can't manage @dev, return the deepest state from which it * can generate wake events, based on any available PME info. */ static pci_power_t pci_target_state(struct pci_dev *dev) { pci_power_t target_state = PCI_D3hot; if (platform_pci_power_manageable(dev)) { /* * Call the platform to choose the target state of the device * and enable wake-up from this state if supported. */ pci_power_t state = platform_pci_choose_state(dev); switch (state) { case PCI_POWER_ERROR: case PCI_UNKNOWN: break; case PCI_D1: case PCI_D2: if (pci_no_d1d2(dev)) break; default: target_state = state; } } else if (!dev->pm_cap) { target_state = PCI_D0; } else if (device_may_wakeup(&dev->dev)) { /* * Find the deepest state from which the device can generate * wake-up events, make it the target state and enable device * to generate PME#. */ if (dev->pme_support) { while (target_state && !(dev->pme_support & (1 << target_state))) target_state--; } } return target_state; } /** * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state * @dev: Device to handle. * * Choose the power state appropriate for the device depending on whether * it can wake up the system and/or is power manageable by the platform * (PCI_D3hot is the default) and put the device into that state. */ int pci_prepare_to_sleep(struct pci_dev *dev) { pci_power_t target_state = pci_target_state(dev); int error; if (target_state == PCI_POWER_ERROR) return -EIO; /* D3cold during system suspend/hibernate is not supported */ if (target_state > PCI_D3hot) target_state = PCI_D3hot; pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev)); error = pci_set_power_state(dev, target_state); if (error) pci_enable_wake(dev, target_state, false); return error; } /** * pci_back_from_sleep - turn PCI device on during system-wide transition into working state * @dev: Device to handle. * * Disable device's system wake-up capability and put it into D0. */ int pci_back_from_sleep(struct pci_dev *dev) { pci_enable_wake(dev, PCI_D0, false); return pci_set_power_state(dev, PCI_D0); } /** * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend. * @dev: PCI device being suspended. * * Prepare @dev to generate wake-up events at run time and put it into a low * power state. */ int pci_finish_runtime_suspend(struct pci_dev *dev) { pci_power_t target_state = pci_target_state(dev); int error; if (target_state == PCI_POWER_ERROR) return -EIO; dev->runtime_d3cold = target_state == PCI_D3cold; __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev)); error = pci_set_power_state(dev, target_state); if (error) { __pci_enable_wake(dev, target_state, true, false); dev->runtime_d3cold = false; } return error; } /** * pci_dev_run_wake - Check if device can generate run-time wake-up events. * @dev: Device to check. * * Return true if the device itself is capable of generating wake-up events * (through the platform or using the native PCIe PME) or if the device supports * PME and one of its upstream bridges can generate wake-up events. */ bool pci_dev_run_wake(struct pci_dev *dev) { struct pci_bus *bus = dev->bus; if (device_run_wake(&dev->dev)) return true; if (!dev->pme_support) return false; while (bus->parent) { struct pci_dev *bridge = bus->self; if (device_run_wake(&bridge->dev)) return true; bus = bus->parent; } /* We have reached the root bus. */ if (bus->bridge) return device_run_wake(bus->bridge); return false; } EXPORT_SYMBOL_GPL(pci_dev_run_wake); void pci_config_pm_runtime_get(struct pci_dev *pdev) { struct device *dev = &pdev->dev; struct device *parent = dev->parent; if (parent) pm_runtime_get_sync(parent); pm_runtime_get_noresume(dev); /* * pdev->current_state is set to PCI_D3cold during suspending, * so wait until suspending completes */ pm_runtime_barrier(dev); /* * Only need to resume devices in D3cold, because config * registers are still accessible for devices suspended but * not in D3cold. */ if (pdev->current_state == PCI_D3cold) pm_runtime_resume(dev); } void pci_config_pm_runtime_put(struct pci_dev *pdev) { struct device *dev = &pdev->dev; struct device *parent = dev->parent; pm_runtime_put(dev); if (parent) pm_runtime_put_sync(parent); } /** * pci_pm_init - Initialize PM functions of given PCI device * @dev: PCI device to handle. */ void pci_pm_init(struct pci_dev *dev) { int pm; u16 pmc; pm_runtime_forbid(&dev->dev); pm_runtime_set_active(&dev->dev); pm_runtime_enable(&dev->dev); device_enable_async_suspend(&dev->dev); dev->wakeup_prepared = false; dev->pm_cap = 0; dev->pme_support = 0; /* find PCI PM capability in list */ pm = pci_find_capability(dev, PCI_CAP_ID_PM); if (!pm) return; /* Check device's ability to generate PME# */ pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc); if ((pmc & PCI_PM_CAP_VER_MASK) > 3) { dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n", pmc & PCI_PM_CAP_VER_MASK); return; } dev->pm_cap = pm; dev->d3_delay = PCI_PM_D3_WAIT; dev->d3cold_delay = PCI_PM_D3COLD_WAIT; dev->d3cold_allowed = true; dev->d1_support = false; dev->d2_support = false; if (!pci_no_d1d2(dev)) { if (pmc & PCI_PM_CAP_D1) dev->d1_support = true; if (pmc & PCI_PM_CAP_D2) dev->d2_support = true; if (dev->d1_support || dev->d2_support) dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n", dev->d1_support ? " D1" : "", dev->d2_support ? " D2" : ""); } pmc &= PCI_PM_CAP_PME_MASK; if (pmc) { dev_printk(KERN_DEBUG, &dev->dev, "PME# supported from%s%s%s%s%s\n", (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "", (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "", (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "", (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "", (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : ""); dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT; dev->pme_poll = true; /* * Make device's PM flags reflect the wake-up capability, but * let the user space enable it to wake up the system as needed. */ device_set_wakeup_capable(&dev->dev, true); /* Disable the PME# generation functionality */ pci_pme_active(dev, false); } } static void pci_add_saved_cap(struct pci_dev *pci_dev, struct pci_cap_saved_state *new_cap) { hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space); } /** * _pci_add_cap_save_buffer - allocate buffer for saving given * capability registers * @dev: the PCI device * @cap: the capability to allocate the buffer for * @extended: Standard or Extended capability ID * @size: requested size of the buffer */ static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap, bool extended, unsigned int size) { int pos; struct pci_cap_saved_state *save_state; if (extended) pos = pci_find_ext_capability(dev, cap); else pos = pci_find_capability(dev, cap); if (pos <= 0) return 0; save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL); if (!save_state) return -ENOMEM; save_state->cap.cap_nr = cap; save_state->cap.cap_extended = extended; save_state->cap.size = size; pci_add_saved_cap(dev, save_state); return 0; } int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size) { return _pci_add_cap_save_buffer(dev, cap, false, size); } int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size) { return _pci_add_cap_save_buffer(dev, cap, true, size); } /** * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities * @dev: the PCI device */ void pci_allocate_cap_save_buffers(struct pci_dev *dev) { int error; error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP, PCI_EXP_SAVE_REGS * sizeof(u16)); if (error) dev_err(&dev->dev, "unable to preallocate PCI Express save buffer\n"); error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16)); if (error) dev_err(&dev->dev, "unable to preallocate PCI-X save buffer\n"); pci_allocate_vc_save_buffers(dev); } void pci_free_cap_save_buffers(struct pci_dev *dev) { struct pci_cap_saved_state *tmp; struct hlist_node *n; hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next) kfree(tmp); } /** * pci_configure_ari - enable or disable ARI forwarding * @dev: the PCI device * * If @dev and its upstream bridge both support ARI, enable ARI in the * bridge. Otherwise, disable ARI in the bridge. */ void pci_configure_ari(struct pci_dev *dev) { u32 cap; struct pci_dev *bridge; if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn) return; bridge = dev->bus->self; if (!bridge) return; pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap); if (!(cap & PCI_EXP_DEVCAP2_ARI)) return; if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) { pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_ARI); bridge->ari_enabled = 1; } else { pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_ARI); bridge->ari_enabled = 0; } } static int pci_acs_enable; /** * pci_request_acs - ask for ACS to be enabled if supported */ void pci_request_acs(void) { pci_acs_enable = 1; } /** * pci_enable_acs - enable ACS if hardware support it * @dev: the PCI device */ void pci_enable_acs(struct pci_dev *dev) { int pos; u16 cap; u16 ctrl; if (!pci_acs_enable) return; pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS); if (!pos) return; pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap); pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl); /* Source Validation */ ctrl |= (cap & PCI_ACS_SV); /* P2P Request Redirect */ ctrl |= (cap & PCI_ACS_RR); /* P2P Completion Redirect */ ctrl |= (cap & PCI_ACS_CR); /* Upstream Forwarding */ ctrl |= (cap & PCI_ACS_UF); pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl); } static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags) { int pos; u16 cap, ctrl; pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS); if (!pos) return false; /* * Except for egress control, capabilities are either required * or only required if controllable. Features missing from the * capability field can therefore be assumed as hard-wired enabled. */ pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap); acs_flags &= (cap | PCI_ACS_EC); pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl); return (ctrl & acs_flags) == acs_flags; } /** * pci_acs_enabled - test ACS against required flags for a given device * @pdev: device to test * @acs_flags: required PCI ACS flags * * Return true if the device supports the provided flags. Automatically * filters out flags that are not implemented on multifunction devices. * * Note that this interface checks the effective ACS capabilities of the * device rather than the actual capabilities. For instance, most single * function endpoints are not required to support ACS because they have no * opportunity for peer-to-peer access. We therefore return 'true' * regardless of whether the device exposes an ACS capability. This makes * it much easier for callers of this function to ignore the actual type * or topology of the device when testing ACS support. */ bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags) { int ret; ret = pci_dev_specific_acs_enabled(pdev, acs_flags); if (ret >= 0) return ret > 0; /* * Conventional PCI and PCI-X devices never support ACS, either * effectively or actually. The shared bus topology implies that * any device on the bus can receive or snoop DMA. */ if (!pci_is_pcie(pdev)) return false; switch (pci_pcie_type(pdev)) { /* * PCI/X-to-PCIe bridges are not specifically mentioned by the spec, * but since their primary interface is PCI/X, we conservatively * handle them as we would a non-PCIe device. */ case PCI_EXP_TYPE_PCIE_BRIDGE: /* * PCIe 3.0, 6.12.1 excludes ACS on these devices. "ACS is never * applicable... must never implement an ACS Extended Capability...". * This seems arbitrary, but we take a conservative interpretation * of this statement. */ case PCI_EXP_TYPE_PCI_BRIDGE: case PCI_EXP_TYPE_RC_EC: return false; /* * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should * implement ACS in order to indicate their peer-to-peer capabilities, * regardless of whether they are single- or multi-function devices. */ case PCI_EXP_TYPE_DOWNSTREAM: case PCI_EXP_TYPE_ROOT_PORT: return pci_acs_flags_enabled(pdev, acs_flags); /* * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be * implemented by the remaining PCIe types to indicate peer-to-peer * capabilities, but only when they are part of a multifunction * device. The footnote for section 6.12 indicates the specific * PCIe types included here. */ case PCI_EXP_TYPE_ENDPOINT: case PCI_EXP_TYPE_UPSTREAM: case PCI_EXP_TYPE_LEG_END: case PCI_EXP_TYPE_RC_END: if (!pdev->multifunction) break; return pci_acs_flags_enabled(pdev, acs_flags); } /* * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable * to single function devices with the exception of downstream ports. */ return true; } /** * pci_acs_path_enable - test ACS flags from start to end in a hierarchy * @start: starting downstream device * @end: ending upstream device or NULL to search to the root bus * @acs_flags: required flags * * Walk up a device tree from start to end testing PCI ACS support. If * any step along the way does not support the required flags, return false. */ bool pci_acs_path_enabled(struct pci_dev *start, struct pci_dev *end, u16 acs_flags) { struct pci_dev *pdev, *parent = start; do { pdev = parent; if (!pci_acs_enabled(pdev, acs_flags)) return false; if (pci_is_root_bus(pdev->bus)) return (end == NULL); parent = pdev->bus->self; } while (pdev != end); return true; } /** * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge * @dev: the PCI device * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD) * * Perform INTx swizzling for a device behind one level of bridge. This is * required by section 9.1 of the PCI-to-PCI bridge specification for devices * behind bridges on add-in cards. For devices with ARI enabled, the slot * number is always 0 (see the Implementation Note in section 2.2.8.1 of * the PCI Express Base Specification, Revision 2.1) */ u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin) { int slot; if (pci_ari_enabled(dev->bus)) slot = 0; else slot = PCI_SLOT(dev->devfn); return (((pin - 1) + slot) % 4) + 1; } int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge) { u8 pin; pin = dev->pin; if (!pin) return -1; while (!pci_is_root_bus(dev->bus)) { pin = pci_swizzle_interrupt_pin(dev, pin); dev = dev->bus->self; } *bridge = dev; return pin; } /** * pci_common_swizzle - swizzle INTx all the way to root bridge * @dev: the PCI device * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD) * * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI * bridges all the way up to a PCI root bus. */ u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp) { u8 pin = *pinp; while (!pci_is_root_bus(dev->bus)) { pin = pci_swizzle_interrupt_pin(dev, pin); dev = dev->bus->self; } *pinp = pin; return PCI_SLOT(dev->devfn); } /** * pci_release_region - Release a PCI bar * @pdev: PCI device whose resources were previously reserved by pci_request_region * @bar: BAR to release * * Releases the PCI I/O and memory resources previously reserved by a * successful call to pci_request_region. Call this function only * after all use of the PCI regions has ceased. */ void pci_release_region(struct pci_dev *pdev, int bar) { struct pci_devres *dr; if (pci_resource_len(pdev, bar) == 0) return; if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) release_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar)); else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) release_mem_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar)); dr = find_pci_dr(pdev); if (dr) dr->region_mask &= ~(1 << bar); } /** * __pci_request_region - Reserved PCI I/O and memory resource * @pdev: PCI device whose resources are to be reserved * @bar: BAR to be reserved * @res_name: Name to be associated with resource. * @exclusive: whether the region access is exclusive or not * * Mark the PCI region associated with PCI device @pdev BR @bar as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * If @exclusive is set, then the region is marked so that userspace * is explicitly not allowed to map the resource via /dev/mem or * sysfs MMIO access. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name, int exclusive) { struct pci_devres *dr; if (pci_resource_len(pdev, bar) == 0) return 0; if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) { if (!request_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar), res_name)) goto err_out; } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) { if (!__request_mem_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar), res_name, exclusive)) goto err_out; } dr = find_pci_dr(pdev); if (dr) dr->region_mask |= 1 << bar; return 0; err_out: dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar, &pdev->resource[bar]); return -EBUSY; } /** * pci_request_region - Reserve PCI I/O and memory resource * @pdev: PCI device whose resources are to be reserved * @bar: BAR to be reserved * @res_name: Name to be associated with resource * * Mark the PCI region associated with PCI device @pdev BAR @bar as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name) { return __pci_request_region(pdev, bar, res_name, 0); } /** * pci_request_region_exclusive - Reserved PCI I/O and memory resource * @pdev: PCI device whose resources are to be reserved * @bar: BAR to be reserved * @res_name: Name to be associated with resource. * * Mark the PCI region associated with PCI device @pdev BR @bar as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. * * The key difference that _exclusive makes it that userspace is * explicitly not allowed to map the resource via /dev/mem or * sysfs. */ int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name) { return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE); } /** * pci_release_selected_regions - Release selected PCI I/O and memory resources * @pdev: PCI device whose resources were previously reserved * @bars: Bitmask of BARs to be released * * Release selected PCI I/O and memory resources previously reserved. * Call this function only after all use of the PCI regions has ceased. */ void pci_release_selected_regions(struct pci_dev *pdev, int bars) { int i; for (i = 0; i < 6; i++) if (bars & (1 << i)) pci_release_region(pdev, i); } static int __pci_request_selected_regions(struct pci_dev *pdev, int bars, const char *res_name, int excl) { int i; for (i = 0; i < 6; i++) if (bars & (1 << i)) if (__pci_request_region(pdev, i, res_name, excl)) goto err_out; return 0; err_out: while(--i >= 0) if (bars & (1 << i)) pci_release_region(pdev, i); return -EBUSY; } /** * pci_request_selected_regions - Reserve selected PCI I/O and memory resources * @pdev: PCI device whose resources are to be reserved * @bars: Bitmask of BARs to be requested * @res_name: Name to be associated with resource */ int pci_request_selected_regions(struct pci_dev *pdev, int bars, const char *res_name) { return __pci_request_selected_regions(pdev, bars, res_name, 0); } int pci_request_selected_regions_exclusive(struct pci_dev *pdev, int bars, const char *res_name) { return __pci_request_selected_regions(pdev, bars, res_name, IORESOURCE_EXCLUSIVE); } /** * pci_release_regions - Release reserved PCI I/O and memory resources * @pdev: PCI device whose resources were previously reserved by pci_request_regions * * Releases all PCI I/O and memory resources previously reserved by a * successful call to pci_request_regions. Call this function only * after all use of the PCI regions has ceased. */ void pci_release_regions(struct pci_dev *pdev) { pci_release_selected_regions(pdev, (1 << 6) - 1); } /** * pci_request_regions - Reserved PCI I/O and memory resources * @pdev: PCI device whose resources are to be reserved * @res_name: Name to be associated with resource. * * Mark all PCI regions associated with PCI device @pdev as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ int pci_request_regions(struct pci_dev *pdev, const char *res_name) { return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name); } /** * pci_request_regions_exclusive - Reserved PCI I/O and memory resources * @pdev: PCI device whose resources are to be reserved * @res_name: Name to be associated with resource. * * Mark all PCI regions associated with PCI device @pdev as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * pci_request_regions_exclusive() will mark the region so that * /dev/mem and the sysfs MMIO access will not be allowed. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name) { return pci_request_selected_regions_exclusive(pdev, ((1 << 6) - 1), res_name); } static void __pci_set_master(struct pci_dev *dev, bool enable) { u16 old_cmd, cmd; pci_read_config_word(dev, PCI_COMMAND, &old_cmd); if (enable) cmd = old_cmd | PCI_COMMAND_MASTER; else cmd = old_cmd & ~PCI_COMMAND_MASTER; if (cmd != old_cmd) { dev_dbg(&dev->dev, "%s bus mastering\n", enable ? "enabling" : "disabling"); pci_write_config_word(dev, PCI_COMMAND, cmd); } dev->is_busmaster = enable; } /** * pcibios_setup - process "pci=" kernel boot arguments * @str: string used to pass in "pci=" kernel boot arguments * * Process kernel boot arguments. This is the default implementation. * Architecture specific implementations can override this as necessary. */ char * __weak __init pcibios_setup(char *str) { return str; } /** * pcibios_set_master - enable PCI bus-mastering for device dev * @dev: the PCI device to enable * * Enables PCI bus-mastering for the device. This is the default * implementation. Architecture specific implementations can override * this if necessary. */ void __weak pcibios_set_master(struct pci_dev *dev) { u8 lat; /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */ if (pci_is_pcie(dev)) return; pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat); if (lat < 16) lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency; else if (lat > pcibios_max_latency) lat = pcibios_max_latency; else return; pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat); } /** * pci_set_master - enables bus-mastering for device dev * @dev: the PCI device to enable * * Enables bus-mastering on the device and calls pcibios_set_master() * to do the needed arch specific settings. */ void pci_set_master(struct pci_dev *dev) { __pci_set_master(dev, true); pcibios_set_master(dev); } /** * pci_clear_master - disables bus-mastering for device dev * @dev: the PCI device to disable */ void pci_clear_master(struct pci_dev *dev) { __pci_set_master(dev, false); } /** * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed * @dev: the PCI device for which MWI is to be enabled * * Helper function for pci_set_mwi. * Originally copied from drivers/net/acenic.c. * Copyright 1998-2001 by Jes Sorensen, . * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int pci_set_cacheline_size(struct pci_dev *dev) { u8 cacheline_size; if (!pci_cache_line_size) return -EINVAL; /* Validate current setting: the PCI_CACHE_LINE_SIZE must be equal to or multiple of the right value. */ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size); if (cacheline_size >= pci_cache_line_size && (cacheline_size % pci_cache_line_size) == 0) return 0; /* Write the correct value. */ pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size); /* Read it back. */ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size); if (cacheline_size == pci_cache_line_size) return 0; dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not " "supported\n", pci_cache_line_size << 2); return -EINVAL; } EXPORT_SYMBOL_GPL(pci_set_cacheline_size); #ifdef PCI_DISABLE_MWI int pci_set_mwi(struct pci_dev *dev) { return 0; } int pci_try_set_mwi(struct pci_dev *dev) { return 0; } void pci_clear_mwi(struct pci_dev *dev) { } #else /** * pci_set_mwi - enables memory-write-invalidate PCI transaction * @dev: the PCI device for which MWI is enabled * * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND. * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int pci_set_mwi(struct pci_dev *dev) { int rc; u16 cmd; rc = pci_set_cacheline_size(dev); if (rc) return rc; pci_read_config_word(dev, PCI_COMMAND, &cmd); if (! (cmd & PCI_COMMAND_INVALIDATE)) { dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n"); cmd |= PCI_COMMAND_INVALIDATE; pci_write_config_word(dev, PCI_COMMAND, cmd); } return 0; } /** * pci_try_set_mwi - enables memory-write-invalidate PCI transaction * @dev: the PCI device for which MWI is enabled * * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND. * Callers are not required to check the return value. * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int pci_try_set_mwi(struct pci_dev *dev) { int rc = pci_set_mwi(dev); return rc; } /** * pci_clear_mwi - disables Memory-Write-Invalidate for device dev * @dev: the PCI device to disable * * Disables PCI Memory-Write-Invalidate transaction on the device */ void pci_clear_mwi(struct pci_dev *dev) { u16 cmd; pci_read_config_word(dev, PCI_COMMAND, &cmd); if (cmd & PCI_COMMAND_INVALIDATE) { cmd &= ~PCI_COMMAND_INVALIDATE; pci_write_config_word(dev, PCI_COMMAND, cmd); } } #endif /* ! PCI_DISABLE_MWI */ /** * pci_intx - enables/disables PCI INTx for device dev * @pdev: the PCI device to operate on * @enable: boolean: whether to enable or disable PCI INTx * * Enables/disables PCI INTx for device dev */ void pci_intx(struct pci_dev *pdev, int enable) { u16 pci_command, new; pci_read_config_word(pdev, PCI_COMMAND, &pci_command); if (enable) { new = pci_command & ~PCI_COMMAND_INTX_DISABLE; } else { new = pci_command | PCI_COMMAND_INTX_DISABLE; } if (new != pci_command) { struct pci_devres *dr; pci_write_config_word(pdev, PCI_COMMAND, new); dr = find_pci_dr(pdev); if (dr && !dr->restore_intx) { dr->restore_intx = 1; dr->orig_intx = !enable; } } } /** * pci_intx_mask_supported - probe for INTx masking support * @dev: the PCI device to operate on * * Check if the device dev support INTx masking via the config space * command word. */ bool pci_intx_mask_supported(struct pci_dev *dev) { bool mask_supported = false; u16 orig, new; if (dev->broken_intx_masking) return false; pci_cfg_access_lock(dev); pci_read_config_word(dev, PCI_COMMAND, &orig); pci_write_config_word(dev, PCI_COMMAND, orig ^ PCI_COMMAND_INTX_DISABLE); pci_read_config_word(dev, PCI_COMMAND, &new); /* * There's no way to protect against hardware bugs or detect them * reliably, but as long as we know what the value should be, let's * go ahead and check it. */ if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) { dev_err(&dev->dev, "Command register changed from " "0x%x to 0x%x: driver or hardware bug?\n", orig, new); } else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) { mask_supported = true; pci_write_config_word(dev, PCI_COMMAND, orig); } pci_cfg_access_unlock(dev); return mask_supported; } EXPORT_SYMBOL_GPL(pci_intx_mask_supported); static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask) { struct pci_bus *bus = dev->bus; bool mask_updated = true; u32 cmd_status_dword; u16 origcmd, newcmd; unsigned long flags; bool irq_pending; /* * We do a single dword read to retrieve both command and status. * Document assumptions that make this possible. */ BUILD_BUG_ON(PCI_COMMAND % 4); BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS); raw_spin_lock_irqsave(&pci_lock, flags); bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword); irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT; /* * Check interrupt status register to see whether our device * triggered the interrupt (when masking) or the next IRQ is * already pending (when unmasking). */ if (mask != irq_pending) { mask_updated = false; goto done; } origcmd = cmd_status_dword; newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE; if (mask) newcmd |= PCI_COMMAND_INTX_DISABLE; if (newcmd != origcmd) bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd); done: raw_spin_unlock_irqrestore(&pci_lock, flags); return mask_updated; } /** * pci_check_and_mask_intx - mask INTx on pending interrupt * @dev: the PCI device to operate on * * Check if the device dev has its INTx line asserted, mask it and * return true in that case. False is returned if not interrupt was * pending. */ bool pci_check_and_mask_intx(struct pci_dev *dev) { return pci_check_and_set_intx_mask(dev, true); } EXPORT_SYMBOL_GPL(pci_check_and_mask_intx); /** * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending * @dev: the PCI device to operate on * * Check if the device dev has its INTx line asserted, unmask it if not * and return true. False is returned and the mask remains active if * there was still an interrupt pending. */ bool pci_check_and_unmask_intx(struct pci_dev *dev) { return pci_check_and_set_intx_mask(dev, false); } EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx); /** * pci_msi_off - disables any MSI or MSI-X capabilities * @dev: the PCI device to operate on * * If you want to use MSI, see pci_enable_msi() and friends. * This is a lower-level primitive that allows us to disable * MSI operation at the device level. */ void pci_msi_off(struct pci_dev *dev) { int pos; u16 control; /* * This looks like it could go in msi.c, but we need it even when * CONFIG_PCI_MSI=n. For the same reason, we can't use * dev->msi_cap or dev->msix_cap here. */ pos = pci_find_capability(dev, PCI_CAP_ID_MSI); if (pos) { pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); control &= ~PCI_MSI_FLAGS_ENABLE; pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); } pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); if (pos) { pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); control &= ~PCI_MSIX_FLAGS_ENABLE; pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); } } EXPORT_SYMBOL_GPL(pci_msi_off); int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size) { return dma_set_max_seg_size(&dev->dev, size); } EXPORT_SYMBOL(pci_set_dma_max_seg_size); int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask) { return dma_set_seg_boundary(&dev->dev, mask); } EXPORT_SYMBOL(pci_set_dma_seg_boundary); /** * pci_wait_for_pending_transaction - waits for pending transaction * @dev: the PCI device to operate on * * Return 0 if transaction is pending 1 otherwise. */ int pci_wait_for_pending_transaction(struct pci_dev *dev) { if (!pci_is_pcie(dev)) return 1; return pci_wait_for_pending(dev, PCI_EXP_DEVSTA, PCI_EXP_DEVSTA_TRPND); } EXPORT_SYMBOL(pci_wait_for_pending_transaction); static int pcie_flr(struct pci_dev *dev, int probe) { u32 cap; pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap); if (!(cap & PCI_EXP_DEVCAP_FLR)) return -ENOTTY; if (probe) return 0; if (!pci_wait_for_pending_transaction(dev)) dev_err(&dev->dev, "transaction is not cleared; proceeding with reset anyway\n"); pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR); msleep(100); return 0; } static int pci_af_flr(struct pci_dev *dev, int probe) { int pos; u8 cap; pos = pci_find_capability(dev, PCI_CAP_ID_AF); if (!pos) return -ENOTTY; pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap); if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR)) return -ENOTTY; if (probe) return 0; /* Wait for Transaction Pending bit clean */ if (pci_wait_for_pending(dev, PCI_AF_STATUS, PCI_AF_STATUS_TP)) goto clear; dev_err(&dev->dev, "transaction is not cleared; " "proceeding with reset anyway\n"); clear: pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR); msleep(100); return 0; } /** * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0. * @dev: Device to reset. * @probe: If set, only check if the device can be reset this way. * * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is * unset, it will be reinitialized internally when going from PCI_D3hot to * PCI_D0. If that's the case and the device is not in a low-power state * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset. * * NOTE: This causes the caller to sleep for twice the device power transition * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms * by default (i.e. unless the @dev's d3_delay field has a different value). * Moreover, only devices in D0 can be reset by this function. */ static int pci_pm_reset(struct pci_dev *dev, int probe) { u16 csr; if (!dev->pm_cap) return -ENOTTY; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr); if (csr & PCI_PM_CTRL_NO_SOFT_RESET) return -ENOTTY; if (probe) return 0; if (dev->current_state != PCI_D0) return -EINVAL; csr &= ~PCI_PM_CTRL_STATE_MASK; csr |= PCI_D3hot; pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr); pci_dev_d3_sleep(dev); csr &= ~PCI_PM_CTRL_STATE_MASK; csr |= PCI_D0; pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr); pci_dev_d3_sleep(dev); return 0; } /** * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge. * @dev: Bridge device * * Use the bridge control register to assert reset on the secondary bus. * Devices on the secondary bus are left in power-on state. */ void pci_reset_bridge_secondary_bus(struct pci_dev *dev) { u16 ctrl; pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl); ctrl |= PCI_BRIDGE_CTL_BUS_RESET; pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl); /* * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double * this to 2ms to ensure that we meet the minimum requirement. */ msleep(2); ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET; pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl); /* * Trhfa for conventional PCI is 2^25 clock cycles. * Assuming a minimum 33MHz clock this results in a 1s * delay before we can consider subordinate devices to * be re-initialized. PCIe has some ways to shorten this, * but we don't make use of them yet. */ ssleep(1); } EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus); static int pci_parent_bus_reset(struct pci_dev *dev, int probe) { struct pci_dev *pdev; if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self) return -ENOTTY; list_for_each_entry(pdev, &dev->bus->devices, bus_list) if (pdev != dev) return -ENOTTY; if (probe) return 0; pci_reset_bridge_secondary_bus(dev->bus->self); return 0; } static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe) { int rc = -ENOTTY; if (!hotplug || !try_module_get(hotplug->ops->owner)) return rc; if (hotplug->ops->reset_slot) rc = hotplug->ops->reset_slot(hotplug, probe); module_put(hotplug->ops->owner); return rc; } static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe) { struct pci_dev *pdev; if (dev->subordinate || !dev->slot) return -ENOTTY; list_for_each_entry(pdev, &dev->bus->devices, bus_list) if (pdev != dev && pdev->slot == dev->slot) return -ENOTTY; return pci_reset_hotplug_slot(dev->slot->hotplug, probe); } static int __pci_dev_reset(struct pci_dev *dev, int probe) { int rc; might_sleep(); rc = pci_dev_specific_reset(dev, probe); if (rc != -ENOTTY) goto done; rc = pcie_flr(dev, probe); if (rc != -ENOTTY) goto done; rc = pci_af_flr(dev, probe); if (rc != -ENOTTY) goto done; rc = pci_pm_reset(dev, probe); if (rc != -ENOTTY) goto done; rc = pci_dev_reset_slot_function(dev, probe); if (rc != -ENOTTY) goto done; rc = pci_parent_bus_reset(dev, probe); done: return rc; } static void pci_dev_lock(struct pci_dev *dev) { pci_cfg_access_lock(dev); /* block PM suspend, driver probe, etc. */ device_lock(&dev->dev); } static void pci_dev_unlock(struct pci_dev *dev) { device_unlock(&dev->dev); pci_cfg_access_unlock(dev); } static void pci_dev_save_and_disable(struct pci_dev *dev) { /* * Wake-up device prior to save. PM registers default to D0 after * reset and a simple register restore doesn't reliably return * to a non-D0 state anyway. */ pci_set_power_state(dev, PCI_D0); pci_save_state(dev); /* * Disable the device by clearing the Command register, except for * INTx-disable which is set. This not only disables MMIO and I/O port * BARs, but also prevents the device from being Bus Master, preventing * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3 * compliant devices, INTx-disable prevents legacy interrupts. */ pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE); } static void pci_dev_restore(struct pci_dev *dev) { pci_restore_state(dev); } static int pci_dev_reset(struct pci_dev *dev, int probe) { int rc; if (!probe) pci_dev_lock(dev); rc = __pci_dev_reset(dev, probe); if (!probe) pci_dev_unlock(dev); return rc; } /** * __pci_reset_function - reset a PCI device function * @dev: PCI device to reset * * Some devices allow an individual function to be reset without affecting * other functions in the same device. The PCI device must be responsive * to PCI config space in order to use this function. * * The device function is presumed to be unused when this function is called. * Resetting the device will make the contents of PCI configuration space * random, so any caller of this must be prepared to reinitialise the * device including MSI, bus mastering, BARs, decoding IO and memory spaces, * etc. * * Returns 0 if the device function was successfully reset or negative if the * device doesn't support resetting a single function. */ int __pci_reset_function(struct pci_dev *dev) { return pci_dev_reset(dev, 0); } EXPORT_SYMBOL_GPL(__pci_reset_function); /** * __pci_reset_function_locked - reset a PCI device function while holding * the @dev mutex lock. * @dev: PCI device to reset * * Some devices allow an individual function to be reset without affecting * other functions in the same device. The PCI device must be responsive * to PCI config space in order to use this function. * * The device function is presumed to be unused and the caller is holding * the device mutex lock when this function is called. * Resetting the device will make the contents of PCI configuration space * random, so any caller of this must be prepared to reinitialise the * device including MSI, bus mastering, BARs, decoding IO and memory spaces, * etc. * * Returns 0 if the device function was successfully reset or negative if the * device doesn't support resetting a single function. */ int __pci_reset_function_locked(struct pci_dev *dev) { return __pci_dev_reset(dev, 0); } EXPORT_SYMBOL_GPL(__pci_reset_function_locked); /** * pci_probe_reset_function - check whether the device can be safely reset * @dev: PCI device to reset * * Some devices allow an individual function to be reset without affecting * other functions in the same device. The PCI device must be responsive * to PCI config space in order to use this function. * * Returns 0 if the device function can be reset or negative if the * device doesn't support resetting a single function. */ int pci_probe_reset_function(struct pci_dev *dev) { return pci_dev_reset(dev, 1); } /** * pci_reset_function - quiesce and reset a PCI device function * @dev: PCI device to reset * * Some devices allow an individual function to be reset without affecting * other functions in the same device. The PCI device must be responsive * to PCI config space in order to use this function. * * This function does not just reset the PCI portion of a device, but * clears all the state associated with the device. This function differs * from __pci_reset_function in that it saves and restores device state * over the reset. * * Returns 0 if the device function was successfully reset or negative if the * device doesn't support resetting a single function. */ int pci_reset_function(struct pci_dev *dev) { int rc; rc = pci_dev_reset(dev, 1); if (rc) return rc; pci_dev_save_and_disable(dev); rc = pci_dev_reset(dev, 0); pci_dev_restore(dev); return rc; } EXPORT_SYMBOL_GPL(pci_reset_function); /* Lock devices from the top of the tree down */ static void pci_bus_lock(struct pci_bus *bus) { struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { pci_dev_lock(dev); if (dev->subordinate) pci_bus_lock(dev->subordinate); } } /* Unlock devices from the bottom of the tree up */ static void pci_bus_unlock(struct pci_bus *bus) { struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { if (dev->subordinate) pci_bus_unlock(dev->subordinate); pci_dev_unlock(dev); } } /* Lock devices from the top of the tree down */ static void pci_slot_lock(struct pci_slot *slot) { struct pci_dev *dev; list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot != slot) continue; pci_dev_lock(dev); if (dev->subordinate) pci_bus_lock(dev->subordinate); } } /* Unlock devices from the bottom of the tree up */ static void pci_slot_unlock(struct pci_slot *slot) { struct pci_dev *dev; list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot != slot) continue; if (dev->subordinate) pci_bus_unlock(dev->subordinate); pci_dev_unlock(dev); } } /* Save and disable devices from the top of the tree down */ static void pci_bus_save_and_disable(struct pci_bus *bus) { struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { pci_dev_save_and_disable(dev); if (dev->subordinate) pci_bus_save_and_disable(dev->subordinate); } } /* * Restore devices from top of the tree down - parent bridges need to be * restored before we can get to subordinate devices. */ static void pci_bus_restore(struct pci_bus *bus) { struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { pci_dev_restore(dev); if (dev->subordinate) pci_bus_restore(dev->subordinate); } } /* Save and disable devices from the top of the tree down */ static void pci_slot_save_and_disable(struct pci_slot *slot) { struct pci_dev *dev; list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot != slot) continue; pci_dev_save_and_disable(dev); if (dev->subordinate) pci_bus_save_and_disable(dev->subordinate); } } /* * Restore devices from top of the tree down - parent bridges need to be * restored before we can get to subordinate devices. */ static void pci_slot_restore(struct pci_slot *slot) { struct pci_dev *dev; list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot != slot) continue; pci_dev_restore(dev); if (dev->subordinate) pci_bus_restore(dev->subordinate); } } static int pci_slot_reset(struct pci_slot *slot, int probe) { int rc; if (!slot) return -ENOTTY; if (!probe) pci_slot_lock(slot); might_sleep(); rc = pci_reset_hotplug_slot(slot->hotplug, probe); if (!probe) pci_slot_unlock(slot); return rc; } /** * pci_probe_reset_slot - probe whether a PCI slot can be reset * @slot: PCI slot to probe * * Return 0 if slot can be reset, negative if a slot reset is not supported. */ int pci_probe_reset_slot(struct pci_slot *slot) { return pci_slot_reset(slot, 1); } EXPORT_SYMBOL_GPL(pci_probe_reset_slot); /** * pci_reset_slot - reset a PCI slot * @slot: PCI slot to reset * * A PCI bus may host multiple slots, each slot may support a reset mechanism * independent of other slots. For instance, some slots may support slot power * control. In the case of a 1:1 bus to slot architecture, this function may * wrap the bus reset to avoid spurious slot related events such as hotplug. * Generally a slot reset should be attempted before a bus reset. All of the * function of the slot and any subordinate buses behind the slot are reset * through this function. PCI config space of all devices in the slot and * behind the slot is saved before and restored after reset. * * Return 0 on success, non-zero on error. */ int pci_reset_slot(struct pci_slot *slot) { int rc; rc = pci_slot_reset(slot, 1); if (rc) return rc; pci_slot_save_and_disable(slot); rc = pci_slot_reset(slot, 0); pci_slot_restore(slot); return rc; } EXPORT_SYMBOL_GPL(pci_reset_slot); static int pci_bus_reset(struct pci_bus *bus, int probe) { if (!bus->self) return -ENOTTY; if (probe) return 0; pci_bus_lock(bus); might_sleep(); pci_reset_bridge_secondary_bus(bus->self); pci_bus_unlock(bus); return 0; } /** * pci_probe_reset_bus - probe whether a PCI bus can be reset * @bus: PCI bus to probe * * Return 0 if bus can be reset, negative if a bus reset is not supported. */ int pci_probe_reset_bus(struct pci_bus *bus) { return pci_bus_reset(bus, 1); } EXPORT_SYMBOL_GPL(pci_probe_reset_bus); /** * pci_reset_bus - reset a PCI bus * @bus: top level PCI bus to reset * * Do a bus reset on the given bus and any subordinate buses, saving * and restoring state of all devices. * * Return 0 on success, non-zero on error. */ int pci_reset_bus(struct pci_bus *bus) { int rc; rc = pci_bus_reset(bus, 1); if (rc) return rc; pci_bus_save_and_disable(bus); rc = pci_bus_reset(bus, 0); pci_bus_restore(bus); return rc; } EXPORT_SYMBOL_GPL(pci_reset_bus); /** * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count * @dev: PCI device to query * * Returns mmrbc: maximum designed memory read count in bytes * or appropriate error value. */ int pcix_get_max_mmrbc(struct pci_dev *dev) { int cap; u32 stat; cap = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (!cap) return -EINVAL; if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat)) return -EINVAL; return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21); } EXPORT_SYMBOL(pcix_get_max_mmrbc); /** * pcix_get_mmrbc - get PCI-X maximum memory read byte count * @dev: PCI device to query * * Returns mmrbc: maximum memory read count in bytes * or appropriate error value. */ int pcix_get_mmrbc(struct pci_dev *dev) { int cap; u16 cmd; cap = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (!cap) return -EINVAL; if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd)) return -EINVAL; return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2); } EXPORT_SYMBOL(pcix_get_mmrbc); /** * pcix_set_mmrbc - set PCI-X maximum memory read byte count * @dev: PCI device to query * @mmrbc: maximum memory read count in bytes * valid values are 512, 1024, 2048, 4096 * * If possible sets maximum memory read byte count, some bridges have erratas * that prevent this. */ int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc) { int cap; u32 stat, v, o; u16 cmd; if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc)) return -EINVAL; v = ffs(mmrbc) - 10; cap = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (!cap) return -EINVAL; if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat)) return -EINVAL; if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21) return -E2BIG; if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd)) return -EINVAL; o = (cmd & PCI_X_CMD_MAX_READ) >> 2; if (o != v) { if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC)) return -EIO; cmd &= ~PCI_X_CMD_MAX_READ; cmd |= v << 2; if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd)) return -EIO; } return 0; } EXPORT_SYMBOL(pcix_set_mmrbc); /** * pcie_get_readrq - get PCI Express read request size * @dev: PCI device to query * * Returns maximum memory read request in bytes * or appropriate error value. */ int pcie_get_readrq(struct pci_dev *dev) { u16 ctl; pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl); return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12); } EXPORT_SYMBOL(pcie_get_readrq); /** * pcie_set_readrq - set PCI Express maximum memory read request * @dev: PCI device to query * @rq: maximum memory read count in bytes * valid values are 128, 256, 512, 1024, 2048, 4096 * * If possible sets maximum memory read request in bytes */ int pcie_set_readrq(struct pci_dev *dev, int rq) { u16 v; if (rq < 128 || rq > 4096 || !is_power_of_2(rq)) return -EINVAL; /* * If using the "performance" PCIe config, we clamp the * read rq size to the max packet size to prevent the * host bridge generating requests larger than we can * cope with */ if (pcie_bus_config == PCIE_BUS_PERFORMANCE) { int mps = pcie_get_mps(dev); if (mps < rq) rq = mps; } v = (ffs(rq) - 8) << 12; return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_READRQ, v); } EXPORT_SYMBOL(pcie_set_readrq); /** * pcie_get_mps - get PCI Express maximum payload size * @dev: PCI device to query * * Returns maximum payload size in bytes */ int pcie_get_mps(struct pci_dev *dev) { u16 ctl; pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl); return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5); } EXPORT_SYMBOL(pcie_get_mps); /** * pcie_set_mps - set PCI Express maximum payload size * @dev: PCI device to query * @mps: maximum payload size in bytes * valid values are 128, 256, 512, 1024, 2048, 4096 * * If possible sets maximum payload size */ int pcie_set_mps(struct pci_dev *dev, int mps) { u16 v; if (mps < 128 || mps > 4096 || !is_power_of_2(mps)) return -EINVAL; v = ffs(mps) - 8; if (v > dev->pcie_mpss) return -EINVAL; v <<= 5; return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_PAYLOAD, v); } EXPORT_SYMBOL(pcie_set_mps); /** * pcie_get_minimum_link - determine minimum link settings of a PCI device * @dev: PCI device to query * @speed: storage for minimum speed * @width: storage for minimum width * * This function will walk up the PCI device chain and determine the minimum * link width and speed of the device. */ int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed, enum pcie_link_width *width) { int ret; *speed = PCI_SPEED_UNKNOWN; *width = PCIE_LNK_WIDTH_UNKNOWN; while (dev) { u16 lnksta; enum pci_bus_speed next_speed; enum pcie_link_width next_width; ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta); if (ret) return ret; next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS]; next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT; if (next_speed < *speed) *speed = next_speed; if (next_width < *width) *width = next_width; dev = dev->bus->self; } return 0; } EXPORT_SYMBOL(pcie_get_minimum_link); /** * pci_select_bars - Make BAR mask from the type of resource * @dev: the PCI device for which BAR mask is made * @flags: resource type mask to be selected * * This helper routine makes bar mask from the type of resource. */ int pci_select_bars(struct pci_dev *dev, unsigned long flags) { int i, bars = 0; for (i = 0; i < PCI_NUM_RESOURCES; i++) if (pci_resource_flags(dev, i) & flags) bars |= (1 << i); return bars; } /** * pci_resource_bar - get position of the BAR associated with a resource * @dev: the PCI device * @resno: the resource number * @type: the BAR type to be filled in * * Returns BAR position in config space, or 0 if the BAR is invalid. */ int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type) { int reg; if (resno < PCI_ROM_RESOURCE) { *type = pci_bar_unknown; return PCI_BASE_ADDRESS_0 + 4 * resno; } else if (resno == PCI_ROM_RESOURCE) { *type = pci_bar_mem32; return dev->rom_base_reg; } else if (resno < PCI_BRIDGE_RESOURCES) { /* device specific resource */ reg = pci_iov_resource_bar(dev, resno, type); if (reg) return reg; } dev_err(&dev->dev, "BAR %d: invalid resource\n", resno); return 0; } /* Some architectures require additional programming to enable VGA */ static arch_set_vga_state_t arch_set_vga_state; void __init pci_register_set_vga_state(arch_set_vga_state_t func) { arch_set_vga_state = func; /* NULL disables */ } static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode, unsigned int command_bits, u32 flags) { if (arch_set_vga_state) return arch_set_vga_state(dev, decode, command_bits, flags); return 0; } /** * pci_set_vga_state - set VGA decode state on device and parents if requested * @dev: the PCI device * @decode: true = enable decoding, false = disable decoding * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY * @flags: traverse ancestors and change bridges * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE */ int pci_set_vga_state(struct pci_dev *dev, bool decode, unsigned int command_bits, u32 flags) { struct pci_bus *bus; struct pci_dev *bridge; u16 cmd; int rc; WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY))); /* ARCH specific VGA enables */ rc = pci_set_vga_state_arch(dev, decode, command_bits, flags); if (rc) return rc; if (flags & PCI_VGA_STATE_CHANGE_DECODES) { pci_read_config_word(dev, PCI_COMMAND, &cmd); if (decode == true) cmd |= command_bits; else cmd &= ~command_bits; pci_write_config_word(dev, PCI_COMMAND, cmd); } if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE)) return 0; bus = dev->bus; while (bus) { bridge = bus->self; if (bridge) { pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, &cmd); if (decode == true) cmd |= PCI_BRIDGE_CTL_VGA; else cmd &= ~PCI_BRIDGE_CTL_VGA; pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, cmd); } bus = bus->parent; } return 0; } #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0}; static DEFINE_SPINLOCK(resource_alignment_lock); /** * pci_specified_resource_alignment - get resource alignment specified by user. * @dev: the PCI device to get * * RETURNS: Resource alignment if it is specified. * Zero if it is not specified. */ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev) { int seg, bus, slot, func, align_order, count; resource_size_t align = 0; char *p; spin_lock(&resource_alignment_lock); p = resource_alignment_param; while (*p) { count = 0; if (sscanf(p, "%d%n", &align_order, &count) == 1 && p[count] == '@') { p += count + 1; } else { align_order = -1; } if (sscanf(p, "%x:%x:%x.%x%n", &seg, &bus, &slot, &func, &count) != 4) { seg = 0; if (sscanf(p, "%x:%x.%x%n", &bus, &slot, &func, &count) != 3) { /* Invalid format */ printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n", p); break; } } p += count; if (seg == pci_domain_nr(dev->bus) && bus == dev->bus->number && slot == PCI_SLOT(dev->devfn) && func == PCI_FUNC(dev->devfn)) { if (align_order == -1) { align = PAGE_SIZE; } else { align = 1 << align_order; } /* Found */ break; } if (*p != ';' && *p != ',') { /* End of param or invalid format */ break; } p++; } spin_unlock(&resource_alignment_lock); return align; } /* * This function disables memory decoding and releases memory resources * of the device specified by kernel's boot parameter 'pci=resource_alignment='. * It also rounds up size to specified alignment. * Later on, the kernel will assign page-aligned memory resource back * to the device. */ void pci_reassigndev_resource_alignment(struct pci_dev *dev) { int i; struct resource *r; resource_size_t align, size; u16 command; /* check if specified PCI is target device to reassign */ align = pci_specified_resource_alignment(dev); if (!align) return; if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL && (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) { dev_warn(&dev->dev, "Can't reassign resources to host bridge.\n"); return; } dev_info(&dev->dev, "Disabling memory decoding and releasing memory resources.\n"); pci_read_config_word(dev, PCI_COMMAND, &command); command &= ~PCI_COMMAND_MEMORY; pci_write_config_word(dev, PCI_COMMAND, command); for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) { r = &dev->resource[i]; if (!(r->flags & IORESOURCE_MEM)) continue; size = resource_size(r); if (size < align) { size = align; dev_info(&dev->dev, "Rounding up size of resource #%d to %#llx.\n", i, (unsigned long long)size); } r->end = size - 1; r->start = 0; } /* Need to disable bridge's resource window, * to enable the kernel to reassign new resource * window later on. */ if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) { for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) { r = &dev->resource[i]; if (!(r->flags & IORESOURCE_MEM)) continue; r->end = resource_size(r) - 1; r->start = 0; } pci_disable_bridge_window(dev); } } static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count) { if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1) count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1; spin_lock(&resource_alignment_lock); strncpy(resource_alignment_param, buf, count); resource_alignment_param[count] = '\0'; spin_unlock(&resource_alignment_lock); return count; } static ssize_t pci_get_resource_alignment_param(char *buf, size_t size) { size_t count; spin_lock(&resource_alignment_lock); count = snprintf(buf, size, "%s", resource_alignment_param); spin_unlock(&resource_alignment_lock); return count; } static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf) { return pci_get_resource_alignment_param(buf, PAGE_SIZE); } static ssize_t pci_resource_alignment_store(struct bus_type *bus, const char *buf, size_t count) { return pci_set_resource_alignment_param(buf, count); } BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show, pci_resource_alignment_store); static int __init pci_resource_alignment_sysfs_init(void) { return bus_create_file(&pci_bus_type, &bus_attr_resource_alignment); } late_initcall(pci_resource_alignment_sysfs_init); static void pci_no_domains(void) { #ifdef CONFIG_PCI_DOMAINS pci_domains_supported = 0; #endif } /** * pci_ext_cfg_avail - can we access extended PCI config space? * * Returns 1 if we can access PCI extended config space (offsets * greater than 0xff). This is the default implementation. Architecture * implementations can override this. */ int __weak pci_ext_cfg_avail(void) { return 1; } void __weak pci_fixup_cardbus(struct pci_bus *bus) { } EXPORT_SYMBOL(pci_fixup_cardbus); static int __init pci_setup(char *str) { while (str) { char *k = strchr(str, ','); if (k) *k++ = 0; if (*str && (str = pcibios_setup(str)) && *str) { if (!strcmp(str, "nomsi")) { pci_no_msi(); } else if (!strcmp(str, "noaer")) { pci_no_aer(); } else if (!strncmp(str, "realloc=", 8)) { pci_realloc_get_opt(str + 8); } else if (!strncmp(str, "realloc", 7)) { pci_realloc_get_opt("on"); } else if (!strcmp(str, "nodomains")) { pci_no_domains(); } else if (!strncmp(str, "noari", 5)) { pcie_ari_disabled = true; } else if (!strncmp(str, "cbiosize=", 9)) { pci_cardbus_io_size = memparse(str + 9, &str); } else if (!strncmp(str, "cbmemsize=", 10)) { pci_cardbus_mem_size = memparse(str + 10, &str); } else if (!strncmp(str, "resource_alignment=", 19)) { pci_set_resource_alignment_param(str + 19, strlen(str + 19)); } else if (!strncmp(str, "ecrc=", 5)) { pcie_ecrc_get_policy(str + 5); } else if (!strncmp(str, "hpiosize=", 9)) { pci_hotplug_io_size = memparse(str + 9, &str); } else if (!strncmp(str, "hpmemsize=", 10)) { pci_hotplug_mem_size = memparse(str + 10, &str); } else if (!strncmp(str, "pcie_bus_tune_off", 17)) { pcie_bus_config = PCIE_BUS_TUNE_OFF; } else if (!strncmp(str, "pcie_bus_safe", 13)) { pcie_bus_config = PCIE_BUS_SAFE; } else if (!strncmp(str, "pcie_bus_perf", 13)) { pcie_bus_config = PCIE_BUS_PERFORMANCE; } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) { pcie_bus_config = PCIE_BUS_PEER2PEER; } else if (!strncmp(str, "pcie_scan_all", 13)) { pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS); } else { printk(KERN_ERR "PCI: Unknown option `%s'\n", str); } } str = k; } return 0; } early_param("pci", pci_setup); EXPORT_SYMBOL(pci_reenable_device); EXPORT_SYMBOL(pci_enable_device_io); EXPORT_SYMBOL(pci_enable_device_mem); EXPORT_SYMBOL(pci_enable_device); EXPORT_SYMBOL(pcim_enable_device); EXPORT_SYMBOL(pcim_pin_device); EXPORT_SYMBOL(pci_disable_device); EXPORT_SYMBOL(pci_find_capability); EXPORT_SYMBOL(pci_bus_find_capability); EXPORT_SYMBOL(pci_release_regions); EXPORT_SYMBOL(pci_request_regions); EXPORT_SYMBOL(pci_request_regions_exclusive); EXPORT_SYMBOL(pci_release_region); EXPORT_SYMBOL(pci_request_region); EXPORT_SYMBOL(pci_request_region_exclusive); EXPORT_SYMBOL(pci_release_selected_regions); EXPORT_SYMBOL(pci_request_selected_regions); EXPORT_SYMBOL(pci_request_selected_regions_exclusive); EXPORT_SYMBOL(pci_set_master); EXPORT_SYMBOL(pci_clear_master); EXPORT_SYMBOL(pci_set_mwi); EXPORT_SYMBOL(pci_try_set_mwi); EXPORT_SYMBOL(pci_clear_mwi); EXPORT_SYMBOL_GPL(pci_intx); EXPORT_SYMBOL(pci_assign_resource); EXPORT_SYMBOL(pci_find_parent_resource); EXPORT_SYMBOL(pci_select_bars); EXPORT_SYMBOL(pci_set_power_state); EXPORT_SYMBOL(pci_save_state); EXPORT_SYMBOL(pci_restore_state); EXPORT_SYMBOL(pci_pme_capable); EXPORT_SYMBOL(pci_pme_active); EXPORT_SYMBOL(pci_wake_from_d3); EXPORT_SYMBOL(pci_prepare_to_sleep); EXPORT_SYMBOL(pci_back_from_sleep); EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);