1a3c98b8bSMyungJoo Hammenuconfig PM_DEVFREQ 2a3c98b8bSMyungJoo Ham bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" 3*83fe27eaSPranith Kumar select SRCU 4a3c98b8bSMyungJoo Ham help 56c81f905SMyungJoo Ham A device may have a list of frequencies and voltages available. 66c81f905SMyungJoo Ham devfreq, a generic DVFS framework can be registered for a device 76c81f905SMyungJoo Ham in order to let the governor provided to devfreq choose an 86c81f905SMyungJoo Ham operating frequency based on the device driver's policy. 9a3c98b8bSMyungJoo Ham 106c81f905SMyungJoo Ham Each device may have its own governor and policy. Devfreq can 11a3c98b8bSMyungJoo Ham reevaluate the device state periodically and/or based on the 126c81f905SMyungJoo Ham notification to "nb", a notifier block, of devfreq. 13a3c98b8bSMyungJoo Ham 146c81f905SMyungJoo Ham Like some CPUs with CPUfreq, a device may have multiple clocks. 15a3c98b8bSMyungJoo Ham However, because the clock frequencies of a single device are 166c81f905SMyungJoo Ham determined by the single device's state, an instance of devfreq 17a3c98b8bSMyungJoo Ham is attached to a single device and returns a "representative" 186c81f905SMyungJoo Ham clock frequency of the device, which is also attached 196c81f905SMyungJoo Ham to a device by 1-to-1. The device registering devfreq takes the 206b2aac42SMasanari Iida responsibility to "interpret" the representative frequency and 21a3c98b8bSMyungJoo Ham to set its every clock accordingly with the "target" callback 226c81f905SMyungJoo Ham given to devfreq. 236c81f905SMyungJoo Ham 246c81f905SMyungJoo Ham When OPP is used with the devfreq device, it is recommended to 256c81f905SMyungJoo Ham register devfreq's nb to the OPP's notifier head. If OPP is 266c81f905SMyungJoo Ham used with the devfreq device, you may use OPP helper 276c81f905SMyungJoo Ham functions defined in devfreq.h. 28a3c98b8bSMyungJoo Ham 29a3c98b8bSMyungJoo Hamif PM_DEVFREQ 30a3c98b8bSMyungJoo Ham 31ce26c5bbSMyungJoo Hamcomment "DEVFREQ Governors" 32ce26c5bbSMyungJoo Ham 33ce26c5bbSMyungJoo Hamconfig DEVFREQ_GOV_SIMPLE_ONDEMAND 34eff607fdSNishanth Menon tristate "Simple Ondemand" 35ce26c5bbSMyungJoo Ham help 36ce26c5bbSMyungJoo Ham Chooses frequency based on the recent load on the device. Works 37ce26c5bbSMyungJoo Ham similar as ONDEMAND governor of CPUFREQ does. A device with 38ce26c5bbSMyungJoo Ham Simple-Ondemand should be able to provide busy/total counter 39ce26c5bbSMyungJoo Ham values that imply the usage rate. A device may provide tuned 40ce26c5bbSMyungJoo Ham values to the governor with data field at devfreq_add_device(). 41ce26c5bbSMyungJoo Ham 42ce26c5bbSMyungJoo Hamconfig DEVFREQ_GOV_PERFORMANCE 43eff607fdSNishanth Menon tristate "Performance" 44ce26c5bbSMyungJoo Ham help 45ce26c5bbSMyungJoo Ham Sets the frequency at the maximum available frequency. 46ce26c5bbSMyungJoo Ham This governor always returns UINT_MAX as frequency so that 47ce26c5bbSMyungJoo Ham the DEVFREQ framework returns the highest frequency available 48ce26c5bbSMyungJoo Ham at any time. 49ce26c5bbSMyungJoo Ham 50ce26c5bbSMyungJoo Hamconfig DEVFREQ_GOV_POWERSAVE 51eff607fdSNishanth Menon tristate "Powersave" 52ce26c5bbSMyungJoo Ham help 53ce26c5bbSMyungJoo Ham Sets the frequency at the minimum available frequency. 54ce26c5bbSMyungJoo Ham This governor always returns 0 as frequency so that 55ce26c5bbSMyungJoo Ham the DEVFREQ framework returns the lowest frequency available 56ce26c5bbSMyungJoo Ham at any time. 57ce26c5bbSMyungJoo Ham 58ce26c5bbSMyungJoo Hamconfig DEVFREQ_GOV_USERSPACE 59eff607fdSNishanth Menon tristate "Userspace" 60ce26c5bbSMyungJoo Ham help 61ce26c5bbSMyungJoo Ham Sets the frequency at the user specified one. 62ce26c5bbSMyungJoo Ham This governor returns the user configured frequency if there 63ce26c5bbSMyungJoo Ham has been an input to /sys/devices/.../power/devfreq_set_freq. 64ce26c5bbSMyungJoo Ham Otherwise, the governor does not change the frequnecy 65ce26c5bbSMyungJoo Ham given at the initialization. 66ce26c5bbSMyungJoo Ham 67a3c98b8bSMyungJoo Hamcomment "DEVFREQ Drivers" 68a3c98b8bSMyungJoo Ham 697b405038SMyungJoo Hamconfig ARM_EXYNOS4_BUS_DEVFREQ 707b405038SMyungJoo Ham bool "ARM Exynos4210/4212/4412 Memory Bus DEVFREQ Driver" 71ba7abeb1SSachin Kamat depends on (CPU_EXYNOS4210 || SOC_EXYNOS4212 || SOC_EXYNOS4412) && !ARCH_MULTIPLATFORM 727b405038SMyungJoo Ham select DEVFREQ_GOV_SIMPLE_ONDEMAND 73b0d5068aSChanwoo Choi select PM_OPP 747b405038SMyungJoo Ham help 757b405038SMyungJoo Ham This adds the DEVFREQ driver for Exynos4210 memory bus (vdd_int) 767b405038SMyungJoo Ham and Exynos4212/4412 memory interface and bus (vdd_mif + vdd_int). 777b405038SMyungJoo Ham It reads PPMU counters of memory controllers and adjusts 787b405038SMyungJoo Ham the operating frequencies and voltages with OPP support. 79cb7063f4SPaul Bolle This does not yet operate with optimal voltages. 807b405038SMyungJoo Ham 816ccce699SAbhilash Kesavanconfig ARM_EXYNOS5_BUS_DEVFREQ 8281da57e6SPunit Agrawal tristate "ARM Exynos5250 Bus DEVFREQ Driver" 836ccce699SAbhilash Kesavan depends on SOC_EXYNOS5250 846ccce699SAbhilash Kesavan select DEVFREQ_GOV_SIMPLE_ONDEMAND 85ae29fa1dSChanwoo Choi select PM_OPP 866ccce699SAbhilash Kesavan help 876ccce699SAbhilash Kesavan This adds the DEVFREQ driver for Exynos5250 bus interface (vdd_int). 886ccce699SAbhilash Kesavan It reads PPMU counters of memory controllers and adjusts the 896ccce699SAbhilash Kesavan operating frequencies and voltages with OPP support. 906ccce699SAbhilash Kesavan 91a3c98b8bSMyungJoo Hamendif # PM_DEVFREQ 92