diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-power | 14 | ||||
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 8 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 2 | ||||
| -rw-r--r-- | Documentation/power/devices.txt | 14 | ||||
| -rw-r--r-- | Documentation/power/notifiers.txt | 51 |
5 files changed, 47 insertions, 42 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 194ca446ac2..b464d12761b 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -158,3 +158,17 @@ Description: successful, will make the kernel abort a subsequent transition to a sleep state if any wakeup events are reported after the write has returned. + +What: /sys/power/reserved_size +Date: May 2011 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/reserved_size file allows user space to control + the amount of memory reserved for allocations made by device + drivers during the "device freeze" stage of hibernation. It can + be written a string representing a non-negative integer that + will be used as the amount of memory to reserve for allocations + made by device drivers' "freeze" callbacks, in bytes. + + Reading from this file will display the current value, which is + set to 1 MB by default. diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 492e81df296..f6a24e8aa11 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -460,14 +460,6 @@ Who: Thomas Gleixner <tglx@linutronix.de> ---------------------------- -What: The acpi_sleep=s4_nonvs command line option -When: 2.6.37 -Files: arch/x86/kernel/acpi/sleep.c -Why: superseded by acpi_sleep=nonvs -Who: Rafael J. Wysocki <rjw@sisk.pl> - ----------------------------- - What: PCI DMA unmap state API When: August 2012 Why: PCI DMA unmap state API (include/linux/pci-dma.h) was replaced diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index cc85a927819..259037b873b 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -245,7 +245,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. acpi_sleep= [HW,ACPI] Sleep options Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, - old_ordering, s4_nonvs, sci_force_enable } + old_ordering, nonvs, sci_force_enable } See Documentation/power/video.txt for information on s3_bios and s3_mode. s3_beep is for debugging; it makes the PC's speaker beep diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 1971bcf48a6..88880839ece 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -279,11 +279,15 @@ When the system goes into the standby or memory sleep state, the phases are: time.) Unlike the other suspend-related phases, during the prepare phase the device tree is traversed top-down. - The prepare phase uses only a bus callback. After the callback method - returns, no new children may be registered below the device. The method - may also prepare the device or driver in some way for the upcoming - system power transition, but it should not put the device into a - low-power state. + In addition to that, if device drivers need to allocate additional + memory to be able to hadle device suspend correctly, that should be + done in the prepare phase. + + After the prepare callback method returns, no new children may be + registered below the device. The method may also prepare the device or + driver in some way for the upcoming system power transition (for + example, by allocating additional memory required for this purpose), but + it should not put the device into a low-power state. 2. The suspend methods should quiesce the device to stop it from performing I/O. They also may save the device registers and put it into the diff --git a/Documentation/power/notifiers.txt b/Documentation/power/notifiers.txt index cf980709122..c2a4a346c0d 100644 --- a/Documentation/power/notifiers.txt +++ b/Documentation/power/notifiers.txt @@ -1,46 +1,41 @@ Suspend notifiers - (C) 2007 Rafael J. Wysocki <rjw@sisk.pl>, GPL - -There are some operations that device drivers may want to carry out in their -.suspend() routines, but shouldn't, because they can cause the hibernation or -suspend to fail. For example, a driver may want to allocate a substantial amount -of memory (like 50 MB) in .suspend(), but that shouldn't be done after the -swsusp's memory shrinker has run. - -Also, there may be some operations, that subsystems want to carry out before a -hibernation/suspend or after a restore/resume, requiring the system to be fully -functional, so the drivers' .suspend() and .resume() routines are not suitable -for this purpose. For example, device drivers may want to upload firmware to -their devices after a restore from a hibernation image, but they cannot do it by -calling request_firmware() from their .resume() routines (user land processes -are frozen at this point). The solution may be to load the firmware into -memory before processes are frozen and upload it from there in the .resume() -routine. Of course, a hibernation notifier may be used for this purpose. - -The subsystems that have such needs can register suspend notifiers that will be -called upon the following events by the suspend core: + (C) 2007-2011 Rafael J. Wysocki <rjw@sisk.pl>, GPL + +There are some operations that subsystems or drivers may want to carry out +before hibernation/suspend or after restore/resume, but they require the system +to be fully functional, so the drivers' and subsystems' .suspend() and .resume() +or even .prepare() and .complete() callbacks are not suitable for this purpose. +For example, device drivers may want to upload firmware to their devices after +resume/restore, but they cannot do it by calling request_firmware() from their +.resume() or .complete() routines (user land processes are frozen at these +points). The solution may be to load the firmware into memory before processes +are frozen and upload it from there in the .resume() routine. +A suspend/hibernation notifier may be used for this purpose. + +The subsystems or drivers having such needs can register suspend notifiers that +will be called upon the following events by the PM core: PM_HIBERNATION_PREPARE The system is going to hibernate or suspend, tasks will be frozen immediately. PM_POST_HIBERNATION The system memory state has been restored from a - hibernation image or an error occurred during the - hibernation. Device drivers' .resume() callbacks have + hibernation image or an error occurred during + hibernation. Device drivers' restore callbacks have been executed and tasks have been thawed. PM_RESTORE_PREPARE The system is going to restore a hibernation image. - If all goes well the restored kernel will issue a + If all goes well, the restored kernel will issue a PM_POST_HIBERNATION notification. -PM_POST_RESTORE An error occurred during the hibernation restore. - Device drivers' .resume() callbacks have been executed +PM_POST_RESTORE An error occurred during restore from hibernation. + Device drivers' restore callbacks have been executed and tasks have been thawed. -PM_SUSPEND_PREPARE The system is preparing for a suspend. +PM_SUSPEND_PREPARE The system is preparing for suspend. PM_POST_SUSPEND The system has just resumed or an error occurred during - the suspend. Device drivers' .resume() callbacks have - been executed and tasks have been thawed. + suspend. Device drivers' resume callbacks have been + executed and tasks have been thawed. It is generally assumed that whatever the notifiers do for PM_HIBERNATION_PREPARE, should be undone for PM_POST_HIBERNATION. Analogously, |