1
2menuconfig PM_DEVFREQ
3 bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support"
4 select SRCU
5 select PM_OPP
6 help
7 A device may have a list of frequencies and voltages available.
8 devfreq, a generic DVFS framework can be registered for a device
9 in order to let the governor provided to devfreq choose an
10 operating frequency based on the device driver's policy.
11
12 Each device may have its own governor and policy. Devfreq can
13 reevaluate the device state periodically and/or based on the
14 notification to "nb", a notifier block, of devfreq.
15
16 Like some CPUs with CPUfreq, a device may have multiple clocks.
17 However, because the clock frequencies of a single device are
18 determined by the single device's state, an instance of devfreq
19 is attached to a single device and returns a "representative"
20 clock frequency of the device, which is also attached
21 to a device by 1-to-1. The device registering devfreq takes the
22 responsibility to "interpret" the representative frequency and
23 to set its every clock accordingly with the "target" callback
24 given to devfreq.
25
26 When OPP is used with the devfreq device, it is recommended to
27 register devfreq's nb to the OPP's notifier head. If OPP is
28 used with the devfreq device, you may use OPP helper
29 functions defined in devfreq.h.
30
31if PM_DEVFREQ
32
33comment "DEVFREQ Governors"
34
35config DEVFREQ_GOV_SIMPLE_ONDEMAND
36 tristate "Simple Ondemand"
37 help
38 Chooses frequency based on the recent load on the device. Works
39 similar as ONDEMAND governor of CPUFREQ does. A device with
40 Simple-Ondemand should be able to provide busy/total counter
41 values that imply the usage rate. A device may provide tuned
42 values to the governor with data field at devfreq_add_device().
43
44config DEVFREQ_GOV_PERFORMANCE
45 tristate "Performance"
46 help
47 Sets the frequency at the maximum available frequency.
48 This governor always returns UINT_MAX as frequency so that
49 the DEVFREQ framework returns the highest frequency available
50 at any time.
51
52config DEVFREQ_GOV_POWERSAVE
53 tristate "Powersave"
54 help
55 Sets the frequency at the minimum available frequency.
56 This governor always returns 0 as frequency so that
57 the DEVFREQ framework returns the lowest frequency available
58 at any time.
59
60config DEVFREQ_GOV_USERSPACE
61 tristate "Userspace"
62 help
63 Sets the frequency at the user specified one.
64 This governor returns the user configured frequency if there
65 has been an input to /sys/devices/.../userspace/set_freq.
66 Otherwise, the governor does not change the frequency
67 given at the initialization.
68
69config DEVFREQ_GOV_PASSIVE
70 tristate "Passive"
71 help
72 Sets the frequency based on the frequency of its parent devfreq
73 device. This governor does not change the frequency by itself
74 through sysfs entries. The passive governor recommends that
75 devfreq device uses the OPP table to get the frequency/voltage.
76
77comment "DEVFREQ Drivers"
78
79config ARM_EXYNOS_BUS_DEVFREQ
80 tristate "ARM Exynos Generic Memory Bus DEVFREQ Driver"
81 depends on ARCH_EXYNOS || COMPILE_TEST
82 select DEVFREQ_GOV_SIMPLE_ONDEMAND
83 select DEVFREQ_GOV_PASSIVE
84 select DEVFREQ_EVENT_EXYNOS_PPMU
85 select PM_DEVFREQ_EVENT
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
94config ARM_IMX_BUS_DEVFREQ
95 tristate "i.MX Generic Bus DEVFREQ Driver"
96 depends on ARCH_MXC || COMPILE_TEST
97 select DEVFREQ_GOV_USERSPACE
98 help
99 This adds the generic DEVFREQ driver for i.MX interconnects. It
100 allows adjusting NIC/NOC frequency.
101
102config ARM_IMX8M_DDRC_DEVFREQ
103 tristate "i.MX8M DDRC DEVFREQ Driver"
104 depends on (ARCH_MXC && HAVE_ARM_SMCCC) || \
105 (COMPILE_TEST && HAVE_ARM_SMCCC)
106 select DEVFREQ_GOV_USERSPACE
107 help
108 This adds the DEVFREQ driver for the i.MX8M DDR Controller. It allows
109 adjusting DRAM frequency.
110
111config ARM_TEGRA_DEVFREQ
112 tristate "NVIDIA Tegra30/114/124/210 DEVFREQ Driver"
113 depends on ARCH_TEGRA_3x_SOC || ARCH_TEGRA_114_SOC || \
114 ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \
115 ARCH_TEGRA_210_SOC || \
116 COMPILE_TEST
117 depends on COMMON_CLK
118 help
119 This adds the DEVFREQ driver for the Tegra family of SoCs.
120 It reads ACTMON counters of memory controllers and adjusts the
121 operating frequencies and voltages with OPP support.
122
123config ARM_RK3399_DMC_DEVFREQ
124 tristate "ARM RK3399 DMC DEVFREQ Driver"
125 depends on (ARCH_ROCKCHIP && HAVE_ARM_SMCCC) || \
126 (COMPILE_TEST && HAVE_ARM_SMCCC)
127 select DEVFREQ_EVENT_ROCKCHIP_DFI
128 select DEVFREQ_GOV_SIMPLE_ONDEMAND
129 select PM_DEVFREQ_EVENT
130 help
131 This adds the DEVFREQ driver for the RK3399 DMC(Dynamic Memory Controller).
132 It sets the frequency for the memory controller and reads the usage counts
133 from hardware.
134
135source "drivers/devfreq/event/Kconfig"
136
137endif
138
