diff options
| author | Lukas Wunner <lukas@wunner.de> | 2016-10-28 11:52:06 +0300 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2016-11-18 03:46:06 +0300 |
| commit | c6a6330706148e7d5265c3dd658d25843c83390f (patch) | |
| tree | 3a6084b514e490879976faa75fb9efc9f8b7638a /drivers/pci/pci.h | |
| parent | e8559b7100324494acbde6e26bcdc6a5a5b4a4ed (diff) | |
| download | linux-c6a6330706148e7d5265c3dd658d25843c83390f.tar.xz | |
PCI: Activate runtime PM on a PCIe port only if it can suspend
Currently pcie_portdrv_probe() activates runtime PM on a PCIe port even
if it will never actually suspend because the BIOS is too old or the
"pcie_port_pm=off" option was specified on the kernel command line.
A few CPU cycles can be saved by not activating runtime PM at all in these
cases, because rpm_idle() and rpm_suspend() will bail out right at the
beginning when calling rpm_check_suspend_allowed(), instead of carrying out
various locking and assignments, invoking rpm_callback(), getting back
-EBUSY and rolling everything back.
The conditions checked in pci_bridge_d3_possible() are all static, they
never change during uptime of the system, hence it's safe to call this to
determine if runtime PM should be activated.
No functional change intended.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/pci/pci.h')
| -rw-r--r-- | drivers/pci/pci.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 27048bb88783..ffffef37ab61 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -85,6 +85,7 @@ 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); +bool pci_bridge_d3_possible(struct pci_dev *dev); void pci_bridge_d3_update(struct pci_dev *dev); static inline void pci_wakeup_event(struct pci_dev *dev) |