| config ARCH_HAS_DEVFREQ | |
| bool | |
| depends on ARCH_HAS_OPP | |
| help | |
| Denotes that the architecture supports DEVFREQ. If the architecture | |
| supports multiple OPP entries per device and the frequency of the | |
| devices with OPPs may be altered dynamically, the architecture | |
| supports DEVFREQ. | |
| menuconfig PM_DEVFREQ | |
| bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" | |
| depends on PM_OPP && ARCH_HAS_DEVFREQ | |
| help | |
| With OPP support, a device may have a list of frequencies and | |
| voltages available. DEVFREQ, a generic DVFS framework can be | |
| registered for a device with OPP support in order to let the | |
| governor provided to DEVFREQ choose an operating frequency | |
| based on the OPP's list and the policy given with DEVFREQ. | |
| Each device may have its own governor and policy. DEVFREQ can | |
| reevaluate the device state periodically and/or based on the | |
| OPP list changes (each frequency/voltage pair in OPP may be | |
| disabled or enabled). | |
| Like some CPUs with CPUFREQ, a device may have multiple clocks. | |
| However, because the clock frequencies of a single device are | |
| determined by the single device's state, an instance of DEVFREQ | |
| is attached to a single device and returns a "representative" | |
| clock frequency from the OPP of the device, which is also attached | |
| to a device by 1-to-1. The device registering DEVFREQ takes the | |
| responsiblity to "interpret" the frequency listed in OPP and | |
| to set its every clock accordingly with the "target" callback | |
| given to DEVFREQ. | |
| if PM_DEVFREQ | |
| comment "DEVFREQ Governors" | |
| config DEVFREQ_GOV_SIMPLE_ONDEMAND | |
| bool "Simple Ondemand" | |
| help | |
| Chooses frequency based on the recent load on the device. Works | |
| similar as ONDEMAND governor of CPUFREQ does. A device with | |
| Simple-Ondemand should be able to provide busy/total counter | |
| values that imply the usage rate. A device may provide tuned | |
| values to the governor with data field at devfreq_add_device(). | |
| config DEVFREQ_GOV_PERFORMANCE | |
| bool "Performance" | |
| help | |
| Sets the frequency at the maximum available frequency. | |
| This governor always returns UINT_MAX as frequency so that | |
| the DEVFREQ framework returns the highest frequency available | |
| at any time. | |
| config DEVFREQ_GOV_POWERSAVE | |
| bool "Powersave" | |
| help | |
| Sets the frequency at the minimum available frequency. | |
| This governor always returns 0 as frequency so that | |
| the DEVFREQ framework returns the lowest frequency available | |
| at any time. | |
| config DEVFREQ_GOV_USERSPACE | |
| bool "Userspace" | |
| help | |
| Sets the frequency at the user specified one. | |
| This governor returns the user configured frequency if there | |
| has been an input to /sys/devices/.../power/devfreq_set_freq. | |
| Otherwise, the governor does not change the frequnecy | |
| given at the initialization. | |
| comment "DEVFREQ Drivers" | |
| endif # PM_DEVFREQ |