Documentation changes based on Pavel's feedback. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx> Index: linux-2.6.22-rc-mm/Documentation/cpuidle/sysfs.txt =================================================================== --- linux-2.6.22-rc-mm.orig/Documentation/cpuidle/sysfs.txt 2007-06-06 11:33:25.000000000 -0700 +++ linux-2.6.22-rc-mm/Documentation/cpuidle/sysfs.txt 2007-06-06 11:35:37.000000000 -0700 @@ -4,14 +4,22 @@ cpuidle sysfs -System global cpuidle information are under +System global cpuidle related information and tunables are under /sys/devices/system/cpu/cpuidle The current interfaces in this directory has self-explanatory names: +* current_driver_ro +* current_governor_ro + +With cpuidle_sysfs_switch boot option (meant for developer testing) +following objects are visible instead. * available_drivers * available_governors * current_driver * current_governor +In this case user can switch the driver, governor at run time by writing +onto current_driver and current_governor. + Per logical CPU specific cpuidle information are under /sys/devices/system/cpu/cpuX/cpuidle @@ -19,9 +27,9 @@ Under this percpu directory, there is a directory for each idle state supported by the driver, which in turn has -* latency -* power -* time -* usage +* latency : Latency to exit out of this idle state (in microseconds) +* power : Power consumed while in this idle state (in milliwatts) +* time : Total time spent in this idle state (in microseconds) +* usage : Number of times this state was entered (count) Index: linux-2.6.22-rc-mm/Documentation/cpuidle/governor.txt =================================================================== --- linux-2.6.22-rc-mm.orig/Documentation/cpuidle/governor.txt 2007-06-06 11:33:25.000000000 -0700 +++ linux-2.6.22-rc-mm/Documentation/cpuidle/governor.txt 2007-06-06 11:33:34.000000000 -0700 @@ -11,12 +11,16 @@ cpuidle governor is policy routine that decides what idle state to enter at any given time. cpuidle core uses different callbacks to governor while handling idle entry. -* select_state callback where governor can determine next idle state to enter -* prepare_idle callback is called before entering an idle state -* scan callback is called after a driver forces redetection of the states +* select_state() callback where governor can determine next idle state to enter +* prepare_idle() callback is called before entering an idle state +* scan() callback is called after a driver forces redetection of the states More than one governor can be registered at the same time and -user can switch between drivers using /sysfs interface. +user can switch between drivers using /sysfs interface (when supported). + +More than one governor part is supported for developers to easily experiment +with different governors. By default, most optimal governor based on your +kernel configuration and platform will be selected by cpuidle. Interfaces: int cpuidle_register_governor(struct cpuidle_governor *gov); Index: linux-2.6.22-rc-mm/Documentation/cpuidle/core.txt =================================================================== --- linux-2.6.22-rc-mm.orig/Documentation/cpuidle/core.txt 2007-06-06 11:33:25.000000000 -0700 +++ linux-2.6.22-rc-mm/Documentation/cpuidle/core.txt 2007-06-06 11:33:34.000000000 -0700 @@ -12,6 +12,6 @@ standardized infrastructure to support independent development of governors and drivers. -cpuidle resides under /drivers/cpuidle. +cpuidle resides under drivers/cpuidle. Index: linux-2.6.22-rc-mm/Documentation/cpuidle/driver.txt =================================================================== --- linux-2.6.22-rc-mm.orig/Documentation/cpuidle/driver.txt 2007-06-06 11:33:25.000000000 -0700 +++ linux-2.6.22-rc-mm/Documentation/cpuidle/driver.txt 2007-06-06 11:33:34.000000000 -0700 @@ -7,16 +7,21 @@ -cpuidle driver supports capability detection for a particular system. The -init and exit routines will be called for each online CPU, with a percpu -cpuidle_driver object and driver should fill in cpuidle_states inside -cpuidle_driver depending on the CPU capability. +cpuidle driver hooks into the cpuidle infrastructure and does the +architecture/platform dependent part of CPU idle states. Driver +provides the platform idle state detection capability and also +has mechanisms in place to support actusl entry-exit into a CPU idle state. + +cpuidle driver supports capability detection for a platform using the +init and exit routines. They will be called for each online CPU, with a +percpu cpuidle_driver object and driver should fill in cpuidle_states +inside cpuidle_driver depending on the CPU capability. Driver can handle dynamic state changes (like battery<->AC), by calling force_redetect interface. It is possible to have more than one driver registered at the same time and -user can switch between drivers using /sysfs interface. +user can switch between drivers using /sysfs interface (when enabled). Interfaces: int cpuidle_register_driver(struct cpuidle_driver *drv); - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
