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-rw-r--r--drivers/pci/pci.c4635
1 files changed, 4635 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
new file mode 100644
index 000000000..c44393f26
--- /dev/null
+++ b/drivers/pci/pci.c
@@ -0,0 +1,4635 @@
+/*
+ * 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 <mj@ucw.cz>
+ */
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/log2.h>
+#include <linux/pci-aspm.h>
+#include <linux/pm_wakeup.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pci_hotplug.h>
+#include <asm-generic/pci-bridge.h>
+#include <asm/setup.h>
+#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 pci_bus *tmp;
+ unsigned char max, n;
+
+ max = bus->busn_res.end;
+ list_for_each_entry(tmp, &bus->children, node) {
+ n = pci_bus_max_busnr(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)
+{
+ struct resource *res = &pdev->resource[bar];
+
+ /*
+ * Make sure the BAR is actually a memory resource, not an IO resource
+ */
+ if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) {
+ dev_warn(&pdev->dev, "can't ioremap BAR %d: %pR\n", bar, res);
+ return NULL;
+ }
+ return ioremap_nocache(res->start, resource_size(res));
+}
+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;
+ u16 ent;
+
+ pci_bus_read_config_byte(bus, devfn, pos, &pos);
+
+ while ((*ttl)--) {
+ if (pos < 0x40)
+ break;
+ pos &= ~3;
+ pci_bus_read_config_word(bus, devfn, pos, &ent);
+
+ id = ent & 0xff;
+ if (id == 0xff)
+ break;
+ if (id == cap)
+ return pos;
+ pos = (ent >> 8);
+ }
+ 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;
+}
+EXPORT_SYMBOL(pci_find_capability);
+
+/**
+ * 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;
+}
+EXPORT_SYMBOL(pci_bus_find_capability);
+
+/**
+ * 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.
+ */
+struct resource *pci_find_parent_resource(const struct pci_dev *dev,
+ struct resource *res)
+{
+ const struct pci_bus *bus = dev->bus;
+ struct resource *r;
+ int i;
+
+ pci_bus_for_each_resource(bus, r, i) {
+ if (!r)
+ continue;
+ if (res->start && resource_contains(r, res)) {
+
+ /*
+ * If the window is prefetchable but the BAR is
+ * not, the allocator made a mistake.
+ */
+ if (r->flags & IORESOURCE_PREFETCH &&
+ !(res->flags & IORESOURCE_PREFETCH))
+ return NULL;
+
+ /*
+ * If we're below a transparent bridge, there may
+ * be both a positively-decoded aperture and a
+ * subtractively-decoded region that contain the BAR.
+ * We want the positively-decoded one, so this depends
+ * on pci_bus_for_each_resource() giving us those
+ * first.
+ */
+ return r;
+ }
+ }
+ return NULL;
+}
+EXPORT_SYMBOL(pci_find_parent_resource);
+
+/**
+ * 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;
+}
+
+static inline bool platform_pci_need_resume(struct pci_dev *dev)
+{
+ return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
+}
+
+/**
+ * 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;
+
+ return error;
+}
+EXPORT_SYMBOL(pci_set_power_state);
+
+/**
+ * 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;
+
+ i = pci_save_pcie_state(dev);
+ if (i != 0)
+ return i;
+
+ i = pci_save_pcix_state(dev);
+ if (i != 0)
+ return i;
+
+ return pci_save_vc_state(dev);
+}
+EXPORT_SYMBOL(pci_save_state);
+
+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;
+}
+EXPORT_SYMBOL(pci_restore_state);
+
+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()
+ */
+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;
+}
+EXPORT_SYMBOL_GPL(pci_load_saved_state);
+
+/**
+ * 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);
+
+int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
+{
+ return pci_enable_resources(dev, bars);
+}
+
+static int do_pci_enable_device(struct pci_dev *dev, int bars)
+{
+ int err;
+ struct pci_dev *bridge;
+ u16 cmd;
+ u8 pin;
+
+ err = pci_set_power_state(dev, PCI_D0);
+ if (err < 0 && err != -EIO)
+ return err;
+
+ bridge = pci_upstream_bridge(dev);
+ if (bridge)
+ pcie_aspm_powersave_config_link(bridge);
+
+ err = pcibios_enable_device(dev, bars);
+ if (err < 0)
+ return err;
+ pci_fixup_device(pci_fixup_enable, dev);
+
+ if (dev->msi_enabled || dev->msix_enabled)
+ return 0;
+
+ pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+ if (pin) {
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+ if (cmd & PCI_COMMAND_INTX_DISABLE)
+ pci_write_config_word(dev, PCI_COMMAND,
+ cmd & ~PCI_COMMAND_INTX_DISABLE);
+ }
+
+ 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;
+}
+EXPORT_SYMBOL(pci_reenable_device);
+
+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);
+}
+EXPORT_SYMBOL(pci_enable_device_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);
+}
+EXPORT_SYMBOL(pci_enable_device_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);
+}
+EXPORT_SYMBOL(pci_enable_device);
+
+/*
+ * 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;
+}
+EXPORT_SYMBOL(pcim_enable_device);
+
+/**
+ * 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;
+}
+EXPORT_SYMBOL(pcim_pin_device);
+
+/*
+ * 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) {}
+
+/**
+ * pcibios_penalize_isa_irq - penalize an ISA IRQ
+ * @irq: ISA IRQ to penalize
+ * @active: IRQ active or not
+ *
+ * Permits the platform to provide architecture-specific functionality when
+ * penalizing ISA IRQs. This is the default implementation. Architecture
+ * implementations can override this.
+ */
+void __weak pcibios_penalize_isa_irq(int irq, int active) {}
+
+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;
+}
+EXPORT_SYMBOL(pci_disable_device);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL_GPL(pci_set_pcie_reset_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));
+}
+EXPORT_SYMBOL(pci_pme_capable);
+
+static void pci_pme_list_scan(struct work_struct *work)
+{
+ struct pci_pme_device *pme_dev, *n;
+
+ mutex_lock(&pci_pme_list_mutex);
+ 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");
+}
+EXPORT_SYMBOL(pci_pme_active);
+
+/**
+ * __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);
+}
+EXPORT_SYMBOL(pci_wake_from_d3);
+
+/**
+ * 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;
+
+ 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;
+}
+EXPORT_SYMBOL(pci_prepare_to_sleep);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_back_from_sleep);
+
+/**
+ * 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);
+
+/**
+ * pci_dev_keep_suspended - Check if the device can stay in the suspended state.
+ * @pci_dev: Device to check.
+ *
+ * Return 'true' if the device is runtime-suspended, it doesn't have to be
+ * reconfigured due to wakeup settings difference between system and runtime
+ * suspend and the current power state of it is suitable for the upcoming
+ * (system) transition.
+ */
+bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
+{
+ struct device *dev = &pci_dev->dev;
+
+ if (!pm_runtime_suspended(dev)
+ || (device_can_wakeup(dev) && !device_may_wakeup(dev))
+ || platform_pci_need_resume(pci_dev))
+ return false;
+
+ return pci_target_state(pci_dev) == pci_dev->current_state;
+}
+
+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_std_enable_acs - enable ACS on devices using standard ACS capabilites
+ * @dev: the PCI device
+ */
+static int pci_std_enable_acs(struct pci_dev *dev)
+{
+ int pos;
+ u16 cap;
+ u16 ctrl;
+
+ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
+ if (!pos)
+ return -ENODEV;
+
+ 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);
+
+ return 0;
+}
+
+/**
+ * pci_enable_acs - enable ACS if hardware support it
+ * @dev: the PCI device
+ */
+void pci_enable_acs(struct pci_dev *dev)
+{
+ if (!pci_acs_enable)
+ return;
+
+ if (!pci_std_enable_acs(dev))
+ return;
+
+ pci_dev_specific_enable_acs(dev);
+}
+
+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);
+}
+EXPORT_SYMBOL_GPL(pci_common_swizzle);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_release_region);
+
+/**
+ * __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);
+}
+EXPORT_SYMBOL(pci_request_region);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_request_region_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);
+}
+EXPORT_SYMBOL(pci_release_selected_regions);
+
+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);
+}
+EXPORT_SYMBOL(pci_request_selected_regions);
+
+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);
+}
+EXPORT_SYMBOL(pci_request_selected_regions_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);
+}
+EXPORT_SYMBOL(pci_release_regions);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_request_regions);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_request_regions_exclusive);
+
+/**
+ * pci_remap_iospace - Remap the memory mapped I/O space
+ * @res: Resource describing the I/O space
+ * @phys_addr: physical address of range to be mapped
+ *
+ * Remap the memory mapped I/O space described by the @res
+ * and the CPU physical address @phys_addr into virtual address space.
+ * Only architectures that have memory mapped IO functions defined
+ * (and the PCI_IOBASE value defined) should call this function.
+ */
+int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
+{
+#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
+ unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
+
+ if (!(res->flags & IORESOURCE_IO))
+ return -EINVAL;
+
+ if (res->end > IO_SPACE_LIMIT)
+ return -EINVAL;
+
+ return ioremap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
+ pgprot_device(PAGE_KERNEL));
+#else
+ /* this architecture does not have memory mapped I/O space,
+ so this function should never be called */
+ WARN_ONCE(1, "This architecture does not support memory mapped I/O\n");
+ return -ENODEV;
+#endif
+}
+
+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);
+}
+EXPORT_SYMBOL(pci_set_master);
+
+/**
+ * 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);
+}
+EXPORT_SYMBOL(pci_clear_master);
+
+/**
+ * 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, <jes@trained-monkey.org>.
+ *
+ * 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);
+
+/**
+ * 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)
+{
+#ifdef PCI_DISABLE_MWI
+ return 0;
+#else
+ 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;
+#endif
+}
+EXPORT_SYMBOL(pci_set_mwi);
+
+/**
+ * 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)
+{
+#ifdef PCI_DISABLE_MWI
+ return 0;
+#else
+ return pci_set_mwi(dev);
+#endif
+}
+EXPORT_SYMBOL(pci_try_set_mwi);
+
+/**
+ * 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)
+{
+#ifndef PCI_DISABLE_MWI
+ 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
+}
+EXPORT_SYMBOL(pci_clear_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;
+ }
+ }
+}
+EXPORT_SYMBOL_GPL(pci_intx);
+
+/**
+ * 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_pcie_cap(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, "timed out waiting for pending transaction; performing function level 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 to clear. A word-aligned test
+ * is used, so we use the conrol offset rather than status and shift
+ * the test bit to match.
+ */
+ if (!pci_wait_for_pending(dev, pos + PCI_AF_CTRL,
+ PCI_AF_STATUS_TP << 8))
+ dev_err(&dev->dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
+
+ 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 || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
+ 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;
+}
+
+void pci_reset_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);
+}
+
+void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
+{
+ pci_reset_secondary_bus(dev);
+}
+
+/**
+ * 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)
+{
+ pcibios_reset_secondary_bus(dev);
+}
+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 || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
+ 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 ||
+ dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
+ 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);
+}
+
+/* Return 1 on successful lock, 0 on contention */
+static int pci_dev_trylock(struct pci_dev *dev)
+{
+ if (pci_cfg_access_trylock(dev)) {
+ if (device_trylock(&dev->dev))
+ return 1;
+ pci_cfg_access_unlock(dev);
+ }
+
+ return 0;
+}
+
+static void pci_dev_unlock(struct pci_dev *dev)
+{
+ device_unlock(&dev->dev);
+ pci_cfg_access_unlock(dev);
+}
+
+/**
+ * pci_reset_notify - notify device driver of reset
+ * @dev: device to be notified of reset
+ * @prepare: 'true' if device is about to be reset; 'false' if reset attempt
+ * completed
+ *
+ * Must be called prior to device access being disabled and after device
+ * access is restored.
+ */
+static void pci_reset_notify(struct pci_dev *dev, bool prepare)
+{
+ const struct pci_error_handlers *err_handler =
+ dev->driver ? dev->driver->err_handler : NULL;
+ if (err_handler && err_handler->reset_notify)
+ err_handler->reset_notify(dev, prepare);
+}
+
+static void pci_dev_save_and_disable(struct pci_dev *dev)
+{
+ pci_reset_notify(dev, true);
+
+ /*
+ * 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);
+ pci_reset_notify(dev, false);
+}
+
+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);
+
+/**
+ * pci_try_reset_function - quiesce and reset a PCI device function
+ * @dev: PCI device to reset
+ *
+ * Same as above, except return -EAGAIN if unable to lock device.
+ */
+int pci_try_reset_function(struct pci_dev *dev)
+{
+ int rc;
+
+ rc = pci_dev_reset(dev, 1);
+ if (rc)
+ return rc;
+
+ pci_dev_save_and_disable(dev);
+
+ if (pci_dev_trylock(dev)) {
+ rc = __pci_dev_reset(dev, 0);
+ pci_dev_unlock(dev);
+ } else
+ rc = -EAGAIN;
+
+ pci_dev_restore(dev);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_try_reset_function);
+
+/* Do any devices on or below this bus prevent a bus reset? */
+static bool pci_bus_resetable(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
+ (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
+ return false;
+ }
+
+ return true;
+}
+
+/* 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);
+ }
+}
+
+/* Return 1 on successful lock, 0 on contention */
+static int pci_bus_trylock(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ if (!pci_dev_trylock(dev))
+ goto unlock;
+ if (dev->subordinate) {
+ if (!pci_bus_trylock(dev->subordinate)) {
+ pci_dev_unlock(dev);
+ goto unlock;
+ }
+ }
+ }
+ return 1;
+
+unlock:
+ list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
+ if (dev->subordinate)
+ pci_bus_unlock(dev->subordinate);
+ pci_dev_unlock(dev);
+ }
+ return 0;
+}
+
+/* Do any devices on or below this slot prevent a bus reset? */
+static bool pci_slot_resetable(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->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
+ (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
+ return false;
+ }
+
+ return true;
+}
+
+/* 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);
+ }
+}
+
+/* Return 1 on successful lock, 0 on contention */
+static int pci_slot_trylock(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 (!pci_dev_trylock(dev))
+ goto unlock;
+ if (dev->subordinate) {
+ if (!pci_bus_trylock(dev->subordinate)) {
+ pci_dev_unlock(dev);
+ goto unlock;
+ }
+ }
+ }
+ return 1;
+
+unlock:
+ list_for_each_entry_continue_reverse(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);
+ }
+ return 0;
+}
+
+/* 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 || !pci_slot_resetable(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);
+
+/**
+ * pci_try_reset_slot - Try to reset a PCI slot
+ * @slot: PCI slot to reset
+ *
+ * Same as above except return -EAGAIN if the slot cannot be locked
+ */
+int pci_try_reset_slot(struct pci_slot *slot)
+{
+ int rc;
+
+ rc = pci_slot_reset(slot, 1);
+ if (rc)
+ return rc;
+
+ pci_slot_save_and_disable(slot);
+
+ if (pci_slot_trylock(slot)) {
+ might_sleep();
+ rc = pci_reset_hotplug_slot(slot->hotplug, 0);
+ pci_slot_unlock(slot);
+ } else
+ rc = -EAGAIN;
+
+ pci_slot_restore(slot);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_try_reset_slot);
+
+static int pci_bus_reset(struct pci_bus *bus, int probe)
+{
+ if (!bus->self || !pci_bus_resetable(bus))
+ 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);
+
+/**
+ * pci_try_reset_bus - Try to reset a PCI bus
+ * @bus: top level PCI bus to reset
+ *
+ * Same as above except return -EAGAIN if the bus cannot be locked
+ */
+int pci_try_reset_bus(struct pci_bus *bus)
+{
+ int rc;
+
+ rc = pci_bus_reset(bus, 1);
+ if (rc)
+ return rc;
+
+ pci_bus_save_and_disable(bus);
+
+ if (pci_bus_trylock(bus)) {
+ might_sleep();
+ pci_reset_bridge_secondary_bus(bus->self);
+ pci_bus_unlock(bus);
+ } else
+ rc = -EAGAIN;
+
+ pci_bus_restore(bus);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_try_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;
+}
+EXPORT_SYMBOL(pci_select_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 */
+ *type = pci_bar_unknown;
+ reg = pci_iov_resource_bar(dev, resno);
+ 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;
+}
+
+bool pci_device_is_present(struct pci_dev *pdev)
+{
+ u32 v;
+
+ return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
+}
+EXPORT_SYMBOL_GPL(pci_device_is_present);
+
+void pci_ignore_hotplug(struct pci_dev *dev)
+{
+ struct pci_dev *bridge = dev->bus->self;
+
+ dev->ignore_hotplug = 1;
+ /* Propagate the "ignore hotplug" setting to the parent bridge. */
+ if (bridge)
+ bridge->ignore_hotplug = 1;
+}
+EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
+
+#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->flags |= IORESOURCE_UNSET;
+ 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->flags |= IORESOURCE_UNSET;
+ 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
+}
+
+#ifdef CONFIG_PCI_DOMAINS
+static atomic_t __domain_nr = ATOMIC_INIT(-1);
+
+int pci_get_new_domain_nr(void)
+{
+ return atomic_inc_return(&__domain_nr);
+}
+
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
+{
+ static int use_dt_domains = -1;
+ int domain = of_get_pci_domain_nr(parent->of_node);
+
+ /*
+ * Check DT domain and use_dt_domains values.
+ *
+ * If DT domain property is valid (domain >= 0) and
+ * use_dt_domains != 0, the DT assignment is valid since this means
+ * we have not previously allocated a domain number by using
+ * pci_get_new_domain_nr(); we should also update use_dt_domains to
+ * 1, to indicate that we have just assigned a domain number from
+ * DT.
+ *
+ * If DT domain property value is not valid (ie domain < 0), and we
+ * have not previously assigned a domain number from DT
+ * (use_dt_domains != 1) we should assign a domain number by
+ * using the:
+ *
+ * pci_get_new_domain_nr()
+ *
+ * API and update the use_dt_domains value to keep track of method we
+ * are using to assign domain numbers (use_dt_domains = 0).
+ *
+ * All other combinations imply we have a platform that is trying
+ * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
+ * which is a recipe for domain mishandling and it is prevented by
+ * invalidating the domain value (domain = -1) and printing a
+ * corresponding error.
+ */
+ if (domain >= 0 && use_dt_domains) {
+ use_dt_domains = 1;
+ } else if (domain < 0 && use_dt_domains != 1) {
+ use_dt_domains = 0;
+ domain = pci_get_new_domain_nr();
+ } else {
+ dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n",
+ parent->of_node->full_name);
+ domain = -1;
+ }
+
+ bus->domain_nr = domain;
+}
+#endif
+#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);