alistair23-linux/drivers/pci/pci.h
Mika Westerberg 9d26d3a8f1 PCI: Put PCIe ports into D3 during suspend
Currently the Linux PCI core does not touch power state of PCI bridges and
PCIe ports when system suspend is entered.  Leaving them in D0 consumes
power unnecessarily and may prevent the CPU from entering deeper C-states.

With recent PCIe hardware we can power down the ports to save power given
that we take into account few restrictions:

  - The PCIe port hardware is recent enough, starting from 2015.

  - Devices connected to PCIe ports are effectively in D3cold once the port
    is transitioned to D3 (the config space is not accessible anymore and
    the link may be powered down).

  - Devices behind the PCIe port need to be allowed to transition to D3cold
    and back.  There is a way both drivers and userspace can forbid this.

  - If the device behind the PCIe port is capable of waking the system it
    needs to be able to do so from D3cold.

This patch adds a new flag to struct pci_device called 'bridge_d3'.  This
flag is set and cleared by the PCI core whenever there is a change in power
management state of any of the devices behind the PCIe port.  When system
later on is suspended we only need to check this flag and if it is true
transition the port to D3 otherwise we leave it in D0.

Also provide override mechanism via command line parameter
"pcie_port_pm=[off|force]" that can be used to disable or enable the
feature regardless of the BIOS manufacturing date.

Tested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-13 14:57:36 -05:00

351 lines
11 KiB
C

#ifndef DRIVERS_PCI_H
#define DRIVERS_PCI_H
#define PCI_CFG_SPACE_SIZE 256
#define PCI_CFG_SPACE_EXP_SIZE 4096
#define PCI_FIND_CAP_TTL 48
extern const unsigned char pcie_link_speed[];
bool pcie_cap_has_lnkctl(const struct pci_dev *dev);
/* Functions internal to the PCI core code */
int pci_create_sysfs_dev_files(struct pci_dev *pdev);
void pci_remove_sysfs_dev_files(struct pci_dev *pdev);
#if !defined(CONFIG_DMI) && !defined(CONFIG_ACPI)
static inline void pci_create_firmware_label_files(struct pci_dev *pdev)
{ return; }
static inline void pci_remove_firmware_label_files(struct pci_dev *pdev)
{ return; }
#else
void pci_create_firmware_label_files(struct pci_dev *pdev);
void pci_remove_firmware_label_files(struct pci_dev *pdev);
#endif
void pci_cleanup_rom(struct pci_dev *dev);
#ifdef HAVE_PCI_MMAP
enum pci_mmap_api {
PCI_MMAP_SYSFS, /* mmap on /sys/bus/pci/devices/<BDF>/resource<N> */
PCI_MMAP_PROCFS /* mmap on /proc/bus/pci/<BDF> */
};
int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai,
enum pci_mmap_api mmap_api);
#endif
int pci_probe_reset_function(struct pci_dev *dev);
/**
* struct pci_platform_pm_ops - Firmware PM callbacks
*
* @is_manageable: returns 'true' if given device is power manageable by the
* platform firmware
*
* @set_state: invokes the platform firmware to set the device's power state
*
* @choose_state: returns PCI power state of given device preferred by the
* platform; to be used during system-wide transitions from a
* sleeping state to the working state and vice versa
*
* @sleep_wake: enables/disables the system wake up capability of given device
*
* @run_wake: enables/disables the platform to generate run-time wake-up events
* for given device (the device's wake-up capability has to be
* enabled by @sleep_wake for this feature to work)
*
* @need_resume: returns 'true' if the given device (which is currently
* suspended) needs to be resumed to be configured for system
* wakeup.
*
* If given platform is generally capable of power managing PCI devices, all of
* these callbacks are mandatory.
*/
struct pci_platform_pm_ops {
bool (*is_manageable)(struct pci_dev *dev);
int (*set_state)(struct pci_dev *dev, pci_power_t state);
pci_power_t (*choose_state)(struct pci_dev *dev);
int (*sleep_wake)(struct pci_dev *dev, bool enable);
int (*run_wake)(struct pci_dev *dev, bool enable);
bool (*need_resume)(struct pci_dev *dev);
};
int pci_set_platform_pm(const struct pci_platform_pm_ops *ops);
void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
void pci_power_up(struct pci_dev *dev);
void pci_disable_enabled_device(struct pci_dev *dev);
int pci_finish_runtime_suspend(struct pci_dev *dev);
int __pci_pme_wakeup(struct pci_dev *dev, void *ign);
bool pci_dev_keep_suspended(struct pci_dev *dev);
void pci_dev_complete_resume(struct pci_dev *pci_dev);
void pci_config_pm_runtime_get(struct pci_dev *dev);
void pci_config_pm_runtime_put(struct pci_dev *dev);
void pci_pm_init(struct pci_dev *dev);
void pci_ea_init(struct pci_dev *dev);
void pci_allocate_cap_save_buffers(struct pci_dev *dev);
void pci_free_cap_save_buffers(struct pci_dev *dev);
void pci_bridge_d3_device_changed(struct pci_dev *dev);
void pci_bridge_d3_device_removed(struct pci_dev *dev);
static inline void pci_wakeup_event(struct pci_dev *dev)
{
/* Wait 100 ms before the system can be put into a sleep state. */
pm_wakeup_event(&dev->dev, 100);
}
static inline bool pci_has_subordinate(struct pci_dev *pci_dev)
{
return !!(pci_dev->subordinate);
}
static inline bool pci_power_manageable(struct pci_dev *pci_dev)
{
/*
* Currently we allow normal PCI devices and PCI bridges transition
* into D3 if their bridge_d3 is set.
*/
return !pci_has_subordinate(pci_dev) || pci_dev->bridge_d3;
}
struct pci_vpd_ops {
ssize_t (*read)(struct pci_dev *dev, loff_t pos, size_t count, void *buf);
ssize_t (*write)(struct pci_dev *dev, loff_t pos, size_t count, const void *buf);
int (*set_size)(struct pci_dev *dev, size_t len);
};
struct pci_vpd {
const struct pci_vpd_ops *ops;
struct bin_attribute *attr; /* descriptor for sysfs VPD entry */
struct mutex lock;
unsigned int len;
u16 flag;
u8 cap;
u8 busy:1;
u8 valid:1;
};
int pci_vpd_init(struct pci_dev *dev);
void pci_vpd_release(struct pci_dev *dev);
/* PCI /proc functions */
#ifdef CONFIG_PROC_FS
int pci_proc_attach_device(struct pci_dev *dev);
int pci_proc_detach_device(struct pci_dev *dev);
int pci_proc_detach_bus(struct pci_bus *bus);
#else
static inline int pci_proc_attach_device(struct pci_dev *dev) { return 0; }
static inline int pci_proc_detach_device(struct pci_dev *dev) { return 0; }
static inline int pci_proc_detach_bus(struct pci_bus *bus) { return 0; }
#endif
/* Functions for PCI Hotplug drivers to use */
int pci_hp_add_bridge(struct pci_dev *dev);
#ifdef HAVE_PCI_LEGACY
void pci_create_legacy_files(struct pci_bus *bus);
void pci_remove_legacy_files(struct pci_bus *bus);
#else
static inline void pci_create_legacy_files(struct pci_bus *bus) { return; }
static inline void pci_remove_legacy_files(struct pci_bus *bus) { return; }
#endif
/* Lock for read/write access to pci device and bus lists */
extern struct rw_semaphore pci_bus_sem;
extern raw_spinlock_t pci_lock;
extern unsigned int pci_pm_d3_delay;
#ifdef CONFIG_PCI_MSI
void pci_no_msi(void);
#else
static inline void pci_no_msi(void) { }
#endif
static inline void pci_msi_set_enable(struct pci_dev *dev, int enable)
{
u16 control;
pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
control &= ~PCI_MSI_FLAGS_ENABLE;
if (enable)
control |= PCI_MSI_FLAGS_ENABLE;
pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
}
static inline void pci_msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
{
u16 ctrl;
pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
ctrl &= ~clear;
ctrl |= set;
pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
}
void pci_realloc_get_opt(char *);
static inline int pci_no_d1d2(struct pci_dev *dev)
{
unsigned int parent_dstates = 0;
if (dev->bus->self)
parent_dstates = dev->bus->self->no_d1d2;
return (dev->no_d1d2 || parent_dstates);
}
extern const struct attribute_group *pci_dev_groups[];
extern const struct attribute_group *pcibus_groups[];
extern struct device_type pci_dev_type;
extern const struct attribute_group *pci_bus_groups[];
/**
* pci_match_one_device - Tell if a PCI device structure has a matching
* PCI device id structure
* @id: single PCI device id structure to match
* @dev: the PCI device structure to match against
*
* Returns the matching pci_device_id structure or %NULL if there is no match.
*/
static inline const struct pci_device_id *
pci_match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
{
if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
(id->device == PCI_ANY_ID || id->device == dev->device) &&
(id->subvendor == PCI_ANY_ID || id->subvendor == dev->subsystem_vendor) &&
(id->subdevice == PCI_ANY_ID || id->subdevice == dev->subsystem_device) &&
!((id->class ^ dev->class) & id->class_mask))
return id;
return NULL;
}
/* PCI slot sysfs helper code */
#define to_pci_slot(s) container_of(s, struct pci_slot, kobj)
extern struct kset *pci_slots_kset;
struct pci_slot_attribute {
struct attribute attr;
ssize_t (*show)(struct pci_slot *, char *);
ssize_t (*store)(struct pci_slot *, const char *, size_t);
};
#define to_pci_slot_attr(s) container_of(s, struct pci_slot_attribute, attr)
enum pci_bar_type {
pci_bar_unknown, /* Standard PCI BAR probe */
pci_bar_io, /* An io port BAR */
pci_bar_mem32, /* A 32-bit memory BAR */
pci_bar_mem64, /* A 64-bit memory BAR */
};
bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *pl,
int crs_timeout);
int pci_setup_device(struct pci_dev *dev);
int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
struct resource *res, unsigned int reg);
int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type);
void pci_configure_ari(struct pci_dev *dev);
void __pci_bus_size_bridges(struct pci_bus *bus,
struct list_head *realloc_head);
void __pci_bus_assign_resources(const struct pci_bus *bus,
struct list_head *realloc_head,
struct list_head *fail_head);
bool pci_bus_clip_resource(struct pci_dev *dev, int idx);
void pci_reassigndev_resource_alignment(struct pci_dev *dev);
void pci_disable_bridge_window(struct pci_dev *dev);
/* Single Root I/O Virtualization */
struct pci_sriov {
int pos; /* capability position */
int nres; /* number of resources */
u32 cap; /* SR-IOV Capabilities */
u16 ctrl; /* SR-IOV Control */
u16 total_VFs; /* total VFs associated with the PF */
u16 initial_VFs; /* initial VFs associated with the PF */
u16 num_VFs; /* number of VFs available */
u16 offset; /* first VF Routing ID offset */
u16 stride; /* following VF stride */
u32 pgsz; /* page size for BAR alignment */
u8 link; /* Function Dependency Link */
u8 max_VF_buses; /* max buses consumed by VFs */
u16 driver_max_VFs; /* max num VFs driver supports */
struct pci_dev *dev; /* lowest numbered PF */
struct pci_dev *self; /* this PF */
struct mutex lock; /* lock for VF bus */
resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */
};
#ifdef CONFIG_PCI_ATS
void pci_restore_ats_state(struct pci_dev *dev);
#else
static inline void pci_restore_ats_state(struct pci_dev *dev)
{
}
#endif /* CONFIG_PCI_ATS */
#ifdef CONFIG_PCI_IOV
int pci_iov_init(struct pci_dev *dev);
void pci_iov_release(struct pci_dev *dev);
int pci_iov_resource_bar(struct pci_dev *dev, int resno);
resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno);
void pci_restore_iov_state(struct pci_dev *dev);
int pci_iov_bus_range(struct pci_bus *bus);
#else
static inline int pci_iov_init(struct pci_dev *dev)
{
return -ENODEV;
}
static inline void pci_iov_release(struct pci_dev *dev)
{
}
static inline int pci_iov_resource_bar(struct pci_dev *dev, int resno)
{
return 0;
}
static inline void pci_restore_iov_state(struct pci_dev *dev)
{
}
static inline int pci_iov_bus_range(struct pci_bus *bus)
{
return 0;
}
#endif /* CONFIG_PCI_IOV */
unsigned long pci_cardbus_resource_alignment(struct resource *);
static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
struct resource *res)
{
#ifdef CONFIG_PCI_IOV
int resno = res - dev->resource;
if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
return pci_sriov_resource_alignment(dev, resno);
#endif
if (dev->class >> 8 == PCI_CLASS_BRIDGE_CARDBUS)
return pci_cardbus_resource_alignment(res);
return resource_alignment(res);
}
void pci_enable_acs(struct pci_dev *dev);
struct pci_dev_reset_methods {
u16 vendor;
u16 device;
int (*reset)(struct pci_dev *dev, int probe);
};
#ifdef CONFIG_PCI_QUIRKS
int pci_dev_specific_reset(struct pci_dev *dev, int probe);
#else
static inline int pci_dev_specific_reset(struct pci_dev *dev, int probe)
{
return -ENOTTY;
}
#endif
#endif /* DRIVERS_PCI_H */