MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 1 | menuconfig PM_DEVFREQ |
| 2 | bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" |
Pranith Kumar | 83fe27e | 2014-12-05 11:24:45 -0500 | [diff] [blame] | 3 | select SRCU |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 4 | help |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 5 | A device may have a list of frequencies and voltages available. |
| 6 | devfreq, a generic DVFS framework can be registered for a device |
| 7 | in order to let the governor provided to devfreq choose an |
| 8 | operating frequency based on the device driver's policy. |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 9 | |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 10 | Each device may have its own governor and policy. Devfreq can |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 11 | reevaluate the device state periodically and/or based on the |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 12 | notification to "nb", a notifier block, of devfreq. |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 13 | |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 14 | Like some CPUs with CPUfreq, a device may have multiple clocks. |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 15 | However, because the clock frequencies of a single device are |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 16 | determined by the single device's state, an instance of devfreq |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 17 | is attached to a single device and returns a "representative" |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 18 | clock frequency of the device, which is also attached |
| 19 | to a device by 1-to-1. The device registering devfreq takes the |
Masanari Iida | 6b2aac4 | 2012-04-14 00:14:11 +0900 | [diff] [blame] | 20 | responsibility to "interpret" the representative frequency and |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 21 | to set its every clock accordingly with the "target" callback |
MyungJoo Ham | 6c81f90 | 2011-11-14 23:31:35 +0100 | [diff] [blame] | 22 | given to devfreq. |
| 23 | |
| 24 | When OPP is used with the devfreq device, it is recommended to |
| 25 | register devfreq's nb to the OPP's notifier head. If OPP is |
| 26 | used with the devfreq device, you may use OPP helper |
| 27 | functions defined in devfreq.h. |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 28 | |
| 29 | if PM_DEVFREQ |
| 30 | |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 31 | comment "DEVFREQ Governors" |
| 32 | |
| 33 | config DEVFREQ_GOV_SIMPLE_ONDEMAND |
Nishanth Menon | eff607f | 2012-10-29 15:01:46 -0500 | [diff] [blame] | 34 | tristate "Simple Ondemand" |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 35 | help |
| 36 | Chooses frequency based on the recent load on the device. Works |
| 37 | similar as ONDEMAND governor of CPUFREQ does. A device with |
| 38 | Simple-Ondemand should be able to provide busy/total counter |
| 39 | values that imply the usage rate. A device may provide tuned |
| 40 | values to the governor with data field at devfreq_add_device(). |
| 41 | |
| 42 | config DEVFREQ_GOV_PERFORMANCE |
Nishanth Menon | eff607f | 2012-10-29 15:01:46 -0500 | [diff] [blame] | 43 | tristate "Performance" |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 44 | help |
| 45 | Sets the frequency at the maximum available frequency. |
| 46 | This governor always returns UINT_MAX as frequency so that |
| 47 | the DEVFREQ framework returns the highest frequency available |
| 48 | at any time. |
| 49 | |
| 50 | config DEVFREQ_GOV_POWERSAVE |
Nishanth Menon | eff607f | 2012-10-29 15:01:46 -0500 | [diff] [blame] | 51 | tristate "Powersave" |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 52 | help |
| 53 | Sets the frequency at the minimum available frequency. |
| 54 | This governor always returns 0 as frequency so that |
| 55 | the DEVFREQ framework returns the lowest frequency available |
| 56 | at any time. |
| 57 | |
| 58 | config DEVFREQ_GOV_USERSPACE |
Nishanth Menon | eff607f | 2012-10-29 15:01:46 -0500 | [diff] [blame] | 59 | tristate "Userspace" |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 60 | help |
| 61 | Sets the frequency at the user specified one. |
| 62 | This governor returns the user configured frequency if there |
| 63 | has been an input to /sys/devices/.../power/devfreq_set_freq. |
Geert Uytterhoeven | 027b693 | 2016-03-14 16:29:02 +0100 | [diff] [blame] | 64 | Otherwise, the governor does not change the frequency |
MyungJoo Ham | ce26c5b | 2011-10-02 00:19:34 +0200 | [diff] [blame] | 65 | given at the initialization. |
| 66 | |
Chanwoo Choi | 9961331 | 2016-03-22 13:44:03 +0900 | [diff] [blame] | 67 | config DEVFREQ_GOV_PASSIVE |
| 68 | tristate "Passive" |
| 69 | help |
| 70 | Sets the frequency based on the frequency of its parent devfreq |
| 71 | device. This governor does not change the frequency by itself |
| 72 | through sysfs entries. The passive governor recommends that |
| 73 | devfreq device uses the OPP table to get the frequency/voltage. |
| 74 | |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 75 | comment "DEVFREQ Drivers" |
| 76 | |
Chanwoo Choi | 0722249 | 2015-11-03 19:04:16 +0900 | [diff] [blame] | 77 | config ARM_EXYNOS_BUS_DEVFREQ |
Paul Gortmaker | 5b3c316 | 2016-06-26 03:43:49 +0900 | [diff] [blame] | 78 | tristate "ARM EXYNOS Generic Memory Bus DEVFREQ Driver" |
Chanwoo Choi | 0722249 | 2015-11-03 19:04:16 +0900 | [diff] [blame] | 79 | depends on ARCH_EXYNOS |
| 80 | select DEVFREQ_GOV_SIMPLE_ONDEMAND |
Chanwoo Choi | 403e068 | 2015-11-05 18:29:27 +0900 | [diff] [blame] | 81 | select DEVFREQ_GOV_PASSIVE |
Chanwoo Choi | 0722249 | 2015-11-03 19:04:16 +0900 | [diff] [blame] | 82 | select DEVFREQ_EVENT_EXYNOS_PPMU |
| 83 | select PM_DEVFREQ_EVENT |
| 84 | select PM_OPP |
| 85 | help |
| 86 | This adds the common DEVFREQ driver for Exynos Memory bus. Exynos |
| 87 | Memory bus has one more group of memory bus (e.g, MIF and INT block). |
| 88 | Each memory bus group could contain many memoby bus block. It reads |
| 89 | PPMU counters of memory controllers by using DEVFREQ-event device |
| 90 | and adjusts the operating frequencies and voltages with OPP support. |
| 91 | This does not yet operate with optimal voltages. |
| 92 | |
Tomeu Vizoso | 6234f38 | 2014-11-24 13:28:17 +0100 | [diff] [blame] | 93 | config ARM_TEGRA_DEVFREQ |
| 94 | tristate "Tegra DEVFREQ Driver" |
| 95 | depends on ARCH_TEGRA_124_SOC |
| 96 | select DEVFREQ_GOV_SIMPLE_ONDEMAND |
| 97 | select PM_OPP |
| 98 | help |
| 99 | This adds the DEVFREQ driver for the Tegra family of SoCs. |
| 100 | It reads ACTMON counters of memory controllers and adjusts the |
| 101 | operating frequencies and voltages with OPP support. |
| 102 | |
Chanwoo Choi | f262f28 | 2015-01-26 13:16:27 +0900 | [diff] [blame] | 103 | source "drivers/devfreq/event/Kconfig" |
| 104 | |
MyungJoo Ham | a3c98b8 | 2011-10-02 00:19:15 +0200 | [diff] [blame] | 105 | endif # PM_DEVFREQ |