menuconfig PM_DEVFREQ bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" help A device may have a list of frequencies and voltages available. devfreq, a generic DVFS framework can be registered for a device in order to let the governor provided to devfreq choose an operating frequency based on the device driver's policy. Each device may have its own governor and policy. Devfreq can reevaluate the device state periodically and/or based on the notification to "nb", a notifier block, of devfreq. 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 of the device, which is also attached to a device by 1-to-1. The device registering devfreq takes the responsibility to "interpret" the representative frequency and to set its every clock accordingly with the "target" callback given to devfreq. When OPP is used with the devfreq device, it is recommended to register devfreq's nb to the OPP's notifier head. If OPP is used with the devfreq device, you may use OPP helper functions defined in devfreq.h. if PM_DEVFREQ comment "DEVFREQ Governors" config DEVFREQ_GOV_SIMPLE_ONDEMAND tristate "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 tristate "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 tristate "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 tristate "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. config DEVFREQ_GOV_MSM_ADRENO_TZ tristate "MSM Adreno Trustzone" depends on MSM_KGSL && MSM_SCM help Trustzone based governor for the Adreno GPU. Sets the frequency using a "on-demand" algorithm. This governor is unlikely to be useful for other devices. config DEVFREQ_GOV_MSM_CPUFREQ bool "MSM CPUfreq" depends on CPU_FREQ_MSM help MSM CPUfreq based governor for CPU bandwidth voting. Sets the CPU to DDR BW vote based on the current CPU frequency. This governor is unlikely to be useful for non-MSM devices. config DEVFREQ_GOV_MSM_BW_HWMON tristate "HW monitor based governor for device BW" depends on ARCH_MSM_KRAIT help HW monitor based governor for device to DDR bandwidth voting. When this governor is used for Krait CPUs, it sets the Krait CPU BW vote by using L2 PM counters to monitor the Krait's use of DDR. Since this uses some of the Krait PM counters it can conflict with existing profiling tools. This governor is unlikely to be useful for non-MSM devices. config DEVFREQ_GOV_MSM_CACHE_HWMON tristate "HW monitor based governor for cache frequency" help HW monitor based governor for cache frequency scaling. This governor currently supports only Krait L2 PM counters. Sets the cache frequency by using L2 PM counters to monitor the Krait's use of the L2. Since this governor uses some of the PM counters it can conflict with existing profiling tools. This governor is unlikely to be useful for other devices. comment "DEVFREQ Drivers" config ARM_EXYNOS4_BUS_DEVFREQ bool "ARM Exynos4210/4212/4412 Memory Bus DEVFREQ Driver" depends on CPU_EXYNOS4210 || CPU_EXYNOS4212 || CPU_EXYNOS4412 select ARCH_HAS_OPP select DEVFREQ_GOV_SIMPLE_ONDEMAND help This adds the DEVFREQ driver for Exynos4210 memory bus (vdd_int) and Exynos4212/4412 memory interface and bus (vdd_mif + vdd_int). It reads PPMU counters of memory controllers and adjusts the operating frequencies and voltages with OPP support. To operate with optimal voltages, ASV support is required (CONFIG_EXYNOS_ASV). endif # PM_DEVFREQ