| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | menuconfig PM_DEVFREQ |
| 2 | bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" |
| 3 | select SRCU |
| 4 | select PM_OPP |
| 5 | help |
| 6 | A device may have a list of frequencies and voltages available. |
| 7 | devfreq, a generic DVFS framework can be registered for a device |
| 8 | in order to let the governor provided to devfreq choose an |
| 9 | operating frequency based on the device driver's policy. |
| 10 | |
| 11 | Each device may have its own governor and policy. Devfreq can |
| 12 | reevaluate the device state periodically and/or based on the |
| 13 | notification to "nb", a notifier block, of devfreq. |
| 14 | |
| 15 | Like some CPUs with CPUfreq, a device may have multiple clocks. |
| 16 | However, because the clock frequencies of a single device are |
| 17 | determined by the single device's state, an instance of devfreq |
| 18 | is attached to a single device and returns a "representative" |
| 19 | clock frequency of the device, which is also attached |
| 20 | to a device by 1-to-1. The device registering devfreq takes the |
| 21 | responsibility to "interpret" the representative frequency and |
| 22 | to set its every clock accordingly with the "target" callback |
| 23 | given to devfreq. |
| 24 | |
| 25 | When OPP is used with the devfreq device, it is recommended to |
| 26 | register devfreq's nb to the OPP's notifier head. If OPP is |
| 27 | used with the devfreq device, you may use OPP helper |
| 28 | functions defined in devfreq.h. |
| 29 | |
| 30 | if PM_DEVFREQ |
| 31 | |
| 32 | comment "DEVFREQ Governors" |
| 33 | |
| 34 | config DEVFREQ_GOV_SIMPLE_ONDEMAND |
| 35 | tristate "Simple Ondemand" |
| 36 | help |
| 37 | Chooses frequency based on the recent load on the device. Works |
| 38 | similar as ONDEMAND governor of CPUFREQ does. A device with |
| 39 | Simple-Ondemand should be able to provide busy/total counter |
| 40 | values that imply the usage rate. A device may provide tuned |
| 41 | values to the governor with data field at devfreq_add_device(). |
| 42 | |
| 43 | config DEVFREQ_GOV_PERFORMANCE |
| 44 | tristate "Performance" |
| 45 | help |
| 46 | Sets the frequency at the maximum available frequency. |
| 47 | This governor always returns UINT_MAX as frequency so that |
| 48 | the DEVFREQ framework returns the highest frequency available |
| 49 | at any time. |
| 50 | |
| 51 | config DEVFREQ_GOV_POWERSAVE |
| 52 | tristate "Powersave" |
| 53 | help |
| 54 | Sets the frequency at the minimum available frequency. |
| 55 | This governor always returns 0 as frequency so that |
| 56 | the DEVFREQ framework returns the lowest frequency available |
| 57 | at any time. |
| 58 | |
| 59 | config DEVFREQ_GOV_USERSPACE |
| 60 | tristate "Userspace" |
| 61 | help |
| 62 | Sets the frequency at the user specified one. |
| 63 | This governor returns the user configured frequency if there |
| 64 | has been an input to /sys/devices/.../power/devfreq_set_freq. |
| 65 | Otherwise, the governor does not change the frequency |
| 66 | given at the initialization. |
| 67 | |
| 68 | config DEVFREQ_GOV_PASSIVE |
| 69 | tristate "Passive" |
| 70 | help |
| 71 | Sets the frequency based on the frequency of its parent devfreq |
| 72 | device. This governor does not change the frequency by itself |
| 73 | through sysfs entries. The passive governor recommends that |
| 74 | devfreq device uses the OPP table to get the frequency/voltage. |
| 75 | |
| 76 | comment "DEVFREQ Drivers" |
| 77 | |
| 78 | config ARM_EXYNOS_BUS_DEVFREQ |
| 79 | tristate "ARM EXYNOS Generic Memory Bus DEVFREQ Driver" |
| 80 | depends on ARCH_EXYNOS || COMPILE_TEST |
| 81 | select DEVFREQ_GOV_SIMPLE_ONDEMAND |
| 82 | select DEVFREQ_GOV_PASSIVE |
| 83 | select DEVFREQ_EVENT_EXYNOS_PPMU |
| 84 | select PM_DEVFREQ_EVENT |
| 85 | select PM_OPP |
| 86 | help |
| 87 | This adds the common DEVFREQ driver for Exynos Memory bus. Exynos |
| 88 | Memory bus has one more group of memory bus (e.g, MIF and INT block). |
| 89 | Each memory bus group could contain many memoby bus block. It reads |
| 90 | PPMU counters of memory controllers by using DEVFREQ-event device |
| 91 | and adjusts the operating frequencies and voltages with OPP support. |
| 92 | This does not yet operate with optimal voltages. |
| 93 | |
| 94 | config ARM_TEGRA_DEVFREQ |
| 95 | tristate "Tegra DEVFREQ Driver" |
| 96 | depends on ARCH_TEGRA_124_SOC |
| 97 | select DEVFREQ_GOV_SIMPLE_ONDEMAND |
| 98 | select PM_OPP |
| 99 | help |
| 100 | This adds the DEVFREQ driver for the Tegra family of SoCs. |
| 101 | It reads ACTMON counters of memory controllers and adjusts the |
| 102 | operating frequencies and voltages with OPP support. |
| 103 | |
| 104 | config ARM_RK3399_DMC_DEVFREQ |
| 105 | tristate "ARM RK3399 DMC DEVFREQ Driver" |
| 106 | depends on ARCH_ROCKCHIP |
| 107 | select DEVFREQ_EVENT_ROCKCHIP_DFI |
| 108 | select DEVFREQ_GOV_SIMPLE_ONDEMAND |
| 109 | select PM_DEVFREQ_EVENT |
| 110 | select PM_OPP |
| 111 | help |
| 112 | This adds the DEVFREQ driver for the RK3399 DMC(Dynamic Memory Controller). |
| 113 | It sets the frequency for the memory controller and reads the usage counts |
| 114 | from hardware. |
| 115 | |
| 116 | source "drivers/devfreq/event/Kconfig" |
| 117 | |
| 118 | endif # PM_DEVFREQ |