X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fcpufreq%2FKconfig;h=2cc71b66231ec07e81d7221578f040c6fdcaeed0;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=889f243fbd16ddc19ab059e471670f02f6307f2a;hpb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;p=linux-2.6.git
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 889f243fb..2cc71b662 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -1,20 +1,59 @@
-config CPU_FREQ_PROC_INTF
- tristate "/proc/cpufreq interface (deprecated)"
- depends on CPU_FREQ && PROC_FS
+config CPU_FREQ
+ bool "CPU Frequency scaling"
help
- This enables the /proc/cpufreq interface for controlling
- CPUFreq. Please note that it is recommended to use the sysfs
- interface instead (which is built automatically).
-
- For details, take a look at .
-
+ CPU Frequency scaling allows you to change the clock speed of
+ CPUs on the fly. This is a nice method to save power, because
+ the lower the CPU clock speed, the less power the CPU consumes.
+
+ Note that this driver doesn't automatically change the CPU
+ clock speed, you need to either enable a dynamic cpufreq governor
+ (see below) after boot, or use a userspace tool.
+
+ For details, take a look at .
+
If in doubt, say N.
+if CPU_FREQ
+
+config CPU_FREQ_TABLE
+ def_tristate m
+
+config CPU_FREQ_DEBUG
+ bool "Enable CPUfreq debugging"
+ help
+ Say Y here to enable CPUfreq subsystem (including drivers)
+ debugging. You will need to activate it via the kernel
+ command line by passing
+ cpufreq.debug=
+
+ To get , add
+ 1 to activate CPUfreq core debugging,
+ 2 to activate CPUfreq drivers debugging, and
+ 4 to activate CPUfreq governor debugging
+
+config CPU_FREQ_STAT
+ tristate "CPU frequency translation statistics"
+ select CPU_FREQ_TABLE
+ default y
+ help
+ This driver exports CPU frequency statistics information through sysfs
+ file system
+
+config CPU_FREQ_STAT_DETAILS
+ bool "CPU frequency translation statistics details"
+ depends on CPU_FREQ_STAT
+ help
+ This will show detail CPU frequency translation table in sysfs file
+ system
+
+# Note that it is not currently possible to set the other governors (such as ondemand)
+# as the default, since if they fail to initialise, cpufreq will be
+# left in an undefined state.
+
choice
prompt "Default CPUFreq governor"
- depends on CPU_FREQ
- default CPU_FREQ_DEFAULT_GOV_PERFORMANCE if !CPU_FREQ_SA1100 && !CPU_FREQ_SA1110
default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110
+ default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
help
This option sets which CPUFreq governor shall be loaded at
startup. If in doubt, select 'performance'.
@@ -33,37 +72,34 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
help
Use the CPUFreq governor 'userspace' as default. This allows
you to set the CPU frequency manually or when an userspace
- programm shall be able to set the CPU dynamically without having
+ program shall be able to set the CPU dynamically without having
to enable the userspace governor manually.
endchoice
config CPU_FREQ_GOV_PERFORMANCE
tristate "'performance' governor"
- depends on CPU_FREQ
help
- This cpufreq governors set the frequency statically to the
+ This cpufreq governor sets the frequency statically to the
highest available CPU frequency.
If in doubt, say Y.
config CPU_FREQ_GOV_POWERSAVE
tristate "'powersave' governor"
- depends on CPU_FREQ
help
- Theis cpufreq governors set the frequency statically to the
+ This cpufreq governor sets the frequency statically to the
lowest available CPU frequency.
If in doubt, say Y.
config CPU_FREQ_GOV_USERSPACE
tristate "'userspace' governor for userspace frequency scaling"
- depends on CPU_FREQ
help
Enable this cpufreq governor when you either want to set the
- CPU frequency manually or when an userspace programm shall
- be able to set the CPU dynamically, like on LART
-
+ CPU frequency manually or when an userspace program shall
+ be able to set the CPU dynamically, like on LART
+ .
For details, take a look at .
@@ -71,7 +107,6 @@ config CPU_FREQ_GOV_USERSPACE
config CPU_FREQ_GOV_ONDEMAND
tristate "'ondemand' cpufreq policy governor"
- depends on CPU_FREQ
help
'ondemand' - This driver adds a dynamic cpufreq policy governor.
The governor does a periodic polling and
@@ -84,16 +119,24 @@ config CPU_FREQ_GOV_ONDEMAND
If in doubt, say N.
-config CPU_FREQ_24_API
- bool "/proc/sys/cpu/ interface (2.4. / OLD)"
- depends on CPU_FREQ && SYSCTL && CPU_FREQ_GOV_USERSPACE
+config CPU_FREQ_GOV_CONSERVATIVE
+ tristate "'conservative' cpufreq governor"
+ depends on CPU_FREQ
help
- This enables the /proc/sys/cpu/ sysctl interface for controlling
- the CPUFreq,"userspace" governor. This is the same interface
- as known from the 2.4.-kernel patches for CPUFreq, and offers
- the same functionality as long as "userspace" is the
- selected governor for the specified CPU.
-
- For details, take a look at .
+ 'conservative' - this driver is rather similar to the 'ondemand'
+ governor both in its source code and its purpose, the difference is
+ its optimisation for better suitability in a battery powered
+ environment. The frequency is gracefully increased and decreased
+ rather than jumping to 100% when speed is required.
+
+ If you have a desktop machine then you should really be considering
+ the 'ondemand' governor instead, however if you are using a laptop,
+ PDA or even an AMD64 based computer (due to the unacceptable
+ step-by-step latency issues between the minimum and maximum frequency
+ transitions in the CPU) you will probably want to use this governor.
+
+ For details, take a look at linux/Documentation/cpu-freq.
If in doubt, say N.
+
+endif # CPU_FREQ