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_ADAPTIVE depends on ARCH_SUN50I || ARCH_SUN8IW10 || ARCH_SUN8IW11 tristate "Adaptive" help Sets the frequency according to dram master access or idle. config DEVFREQ_GOV_TEMPTRIGGER depends on SUN50IW1P1_THERMAL tristate "Temptrigger" help Sets the frequency according to temperature control. config DEVFREQ_GOV_DSM depends on EVB_PLATFORM depends on ARCH_SUN9IW1P1 || ARCH_SUN8IW5P1 || ARCH_SUN8IW6P1 || ARCH_SUN8IW8P1 || ARCH_SUN8IW9P1 bool "Dsm" help Sets the frequency according to dram scene management(DSM). 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). config ARM_SUNXI_DRAM_DEVFREQ bool "ARM Sunxi Dram DEVFREQ Driver" select ARCH_HAS_OPP select PM_OPP depends on ARCH_SUN50I || ARCH_SUN8IW10 || ARCH_SUN8IW11 select DEVFREQ_GOV_PERFORMANCE if ARCH_SUN50IW6 select DEVFREQ_GOV_ADAPTIVE if !ARCH_SUN50IW6 help DRAM Frequency scaling allows you to change the clock speed of DRAM on the fly. This is a nice method to save power, because the lower the DRAM clock speed, the less power the DRAM consumes. If in doubt, say N. config DEVFREQ_DRAM_FREQ_WITH_SOFT_NOTIFY bool "Use dram master notify access or idle in software" depends on ARM_SUNXI_DRAM_DEVFREQ depends on ARCH_SUN50I help This will allow dram master notify access or idle instead of hardware interrupt. If in doubt, say N. config DEVFREQ_DRAM_FREQ bool "DRAM Frequency scaling" depends on DEVFREQ_GOV_USERSPACE || DEVFREQ_GOV_VANS || DEVFREQ_GOV_DSM depends on ARCH_SUN8IW6 || ARCH_SUN8IW5 help DRAM Frequency scaling allows you to change the clock speed of DRAM on the fly. This is a nice method to save power, because the lower the DRAM clock speed, the less power the DRAM consumes. If in doubt, say N. config DEVFREQ_DRAM_FREQ_CFS_SW bool "Change dram frequency in CFS mode, need extra software operation" depends on DEVFREQ_DRAM_FREQ depends on ARCH_SUN8IW6P1 help This will need extra software operation after changing dram frequency in CFS mode. If in doubt, say N. config DEVFREQ_DRAM_FREQ_LOW_POWER_SW bool "Change dram frequency in software mode when low-power music playing" depends on DEVFREQ_DRAM_FREQ depends on ARCH_SUN8IW5P1 help This will use software mode to change dram frequency when low-power music playing. If in doubt, say N. config DEVFREQ_DRAM_FREQ_BUSFREQ bool "Change bus frequency with dram frequency changed when low-power music playing" depends on ARM_SUNXI_DRAM_DEVFREQ || DEVFREQ_DRAM_FREQ depends on ARCH_SUN50I || ARCH_SUN8IW6 || ARCH_SUN8IW5P1 help This will allow bus frequency changed when low-power music playing. If in doubt, say N. config DEVFREQ_DRAM_FREQ_VDDSYS bool "Change vdd-sys with dram frequency changed when low-power music playing" depends on DEVFREQ_DRAM_FREQ depends on ARCH_SUN8IW5P1 help This will allow vdd-sys changed when low-power musiic playing. If in doubt, sya N. config DEVFREQ_DRAM_FREQ_IN_VSYNC bool "Change dram frequency in display vsync" depends on ARM_SUNXI_DRAM_DEVFREQ || DEVFREQ_DRAM_FREQ depends on ARCH_SUN50I || ARCH_SUN8IW10 || ARCH_SUN8IW11 || ARCH_SUN8IW6 || ARCH_SUN8IW5P1 depends on !EINK_PANEL_USED help This will allow dram frequency changed in display vsync. If in doubt, say N. endif # PM_DEVFREQ