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authorBjorn Helgaas <bhelgaas@google.com>2019-11-28 17:54:35 +0300
committerBjorn Helgaas <bhelgaas@google.com>2019-11-28 17:54:35 +0300
commit7cfe16393c3c9fed45545b234b852e1154c7cc5b (patch)
tree417dc942f05a9e1669ecdc107c5ff8abcff94527 /Documentation
parentc59f0da5780f4ea3645020bffc1e261c87aece32 (diff)
parentbae26849372b83c65da73d19ff58e987d70e6600 (diff)
downloadlinux-7cfe16393c3c9fed45545b234b852e1154c7cc5b.tar.xz
Merge branch 'pci/pm'
- Always return devices to D0 when thawing to fix hibernation with drivers like mlx4 that used legacy power management (previously we only did it for drivers with new power management ops) (Dexuan Cui) - Clear PCIe PME Status even for legacy power management (Bjorn Helgaas) - Fix PCI PM documentation errors (Bjorn Helgaas) - Use dev_printk() for more power management messages (Bjorn Helgaas) - Apply D2 delay as milliseconds, not microseconds (Bjorn Helgaas) - Convert xen-platform from legacy to generic power management (Bjorn Helgaas) - Removed unused .resume_early() and .suspend_late() legacy power management hooks (Bjorn Helgaas) - Rearrange power management code for clarity (Rafael J. Wysocki) - Decode power states more clearly ("4" or "D4" really refers to "D3cold") (Bjorn Helgaas) - Notice when reading PM Control register returns an error (~0) instead of interpreting it as being in D3hot (Bjorn Helgaas) - Add missing link delays required by the PCIe spec (Mika Westerberg) * pci/pm: PCI/PM: Move pci_dev_wait() definition earlier PCI/PM: Add missing link delays required by the PCIe spec PCI/PM: Add pcie_wait_for_link_delay() PCI/PM: Return error when changing power state from D3cold PCI/PM: Decode D3cold power state correctly PCI/PM: Fold __pci_complete_power_transition() into its caller PCI/PM: Avoid exporting __pci_complete_power_transition() PCI/PM: Fold __pci_start_power_transition() into its caller PCI/PM: Use pci_power_up() in pci_set_power_state() PCI/PM: Move power state update away from pci_power_up() PCI/PM: Remove unused pci_driver.suspend_late() hook PCI/PM: Remove unused pci_driver.resume_early() hook xen-platform: Convert to generic power management PCI/PM: Simplify pci_set_power_state() PCI/PM: Expand PM reset messages to mention D3hot (not just D3) PCI/PM: Apply D2 delay as milliseconds, not microseconds PCI/PM: Use pci_WARN() to include device information PCI/PM: Use PCI dev_printk() wrappers for consistency PCI/PM: Wrap long lines in documentation PCI/PM: Note that PME can be generated from D0 PCI/PM: Make power management op coding style consistent PCI/PM: Run resume fixups before disabling wakeup events PCI/PM: Clear PCIe PME Status even for legacy power management PCI/PM: Correct pci_pm_thaw_noirq() documentation PCI/PM: Always return devices to D0 when thawing
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/power/pci.rst50
1 files changed, 25 insertions, 25 deletions
diff --git a/Documentation/power/pci.rst b/Documentation/power/pci.rst
index 0e2ef7429304..0924d29636ad 100644
--- a/Documentation/power/pci.rst
+++ b/Documentation/power/pci.rst
@@ -130,8 +130,8 @@ a full power-on reset sequence and the power-on defaults are restored to the
device by hardware just as at initial power up.
PCI devices supporting the PCI PM Spec can be programmed to generate PMEs
-while in a low-power state (D1-D3), but they are not required to be capable
-of generating PMEs from all supported low-power states. In particular, the
+while in any power state (D0-D3), but they are not required to be capable
+of generating PMEs from all supported power states. In particular, the
capability of generating PMEs from D3cold is optional and depends on the
presence of additional voltage (3.3Vaux) allowing the device to remain
sufficiently active to generate a wakeup signal.
@@ -426,12 +426,12 @@ pm->runtime_idle() callback.
2.4. System-Wide Power Transitions
----------------------------------
There are a few different types of system-wide power transitions, described in
-Documentation/driver-api/pm/devices.rst. Each of them requires devices to be handled
-in a specific way and the PM core executes subsystem-level power management
-callbacks for this purpose. They are executed in phases such that each phase
-involves executing the same subsystem-level callback for every device belonging
-to the given subsystem before the next phase begins. These phases always run
-after tasks have been frozen.
+Documentation/driver-api/pm/devices.rst. Each of them requires devices to be
+handled in a specific way and the PM core executes subsystem-level power
+management callbacks for this purpose. They are executed in phases such that
+each phase involves executing the same subsystem-level callback for every device
+belonging to the given subsystem before the next phase begins. These phases
+always run after tasks have been frozen.
2.4.1. System Suspend
^^^^^^^^^^^^^^^^^^^^^
@@ -600,17 +600,17 @@ using the following PCI bus type's callbacks::
respectively.
-The first of them, pci_pm_thaw_noirq(), is analogous to pci_pm_resume_noirq(),
-but it doesn't put the device into the full power state and doesn't attempt to
-restore its standard configuration registers. It also executes the device
-driver's pm->thaw_noirq() callback, if defined, instead of pm->resume_noirq().
+The first of them, pci_pm_thaw_noirq(), is analogous to pci_pm_resume_noirq().
+It puts the device into the full power state and restores its standard
+configuration registers. It also executes the device driver's pm->thaw_noirq()
+callback, if defined, instead of pm->resume_noirq().
The pci_pm_thaw() routine is similar to pci_pm_resume(), but it runs the device
driver's pm->thaw() callback instead of pm->resume(). It is executed
asynchronously for different PCI devices that don't depend on each other in a
known way.
-The complete phase it the same as for system resume.
+The complete phase is the same as for system resume.
After saving the image, devices need to be powered down before the system can
enter the target sleep state (ACPI S4 for ACPI-based systems). This is done in
@@ -636,12 +636,12 @@ System restore requires a hibernation image to be loaded into memory and the
pre-hibernation memory contents to be restored before the pre-hibernation system
activity can be resumed.
-As described in Documentation/driver-api/pm/devices.rst, the hibernation image is loaded
-into memory by a fresh instance of the kernel, called the boot kernel, which in
-turn is loaded and run by a boot loader in the usual way. After the boot kernel
-has loaded the image, it needs to replace its own code and data with the code
-and data of the "hibernated" kernel stored within the image, called the image
-kernel. For this purpose all devices are frozen just like before creating
+As described in Documentation/driver-api/pm/devices.rst, the hibernation image
+is loaded into memory by a fresh instance of the kernel, called the boot kernel,
+which in turn is loaded and run by a boot loader in the usual way. After the
+boot kernel has loaded the image, it needs to replace its own code and data with
+the code and data of the "hibernated" kernel stored within the image, called the
+image kernel. For this purpose all devices are frozen just like before creating
the image during hibernation, in the
prepare, freeze, freeze_noirq
@@ -691,12 +691,12 @@ controlling the runtime power management of their devices.
At the time of this writing there are two ways to define power management
callbacks for a PCI device driver, the recommended one, based on using a
-dev_pm_ops structure described in Documentation/driver-api/pm/devices.rst, and the
-"legacy" one, in which the .suspend(), .suspend_late(), .resume_early(), and
-.resume() callbacks from struct pci_driver are used. The legacy approach,
-however, doesn't allow one to define runtime power management callbacks and is
-not really suitable for any new drivers. Therefore it is not covered by this
-document (refer to the source code to learn more about it).
+dev_pm_ops structure described in Documentation/driver-api/pm/devices.rst, and
+the "legacy" one, in which the .suspend() and .resume() callbacks from struct
+pci_driver are used. The legacy approach, however, doesn't allow one to define
+runtime power management callbacks and is not really suitable for any new
+drivers. Therefore it is not covered by this document (refer to the source code
+to learn more about it).
It is recommended that all PCI device drivers define a struct dev_pm_ops object
containing pointers to power management (PM) callbacks that will be executed by