From 1c2562459faedc35927546cfa5273ec6c2884cce Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Tue, 2 Oct 2007 13:28:12 -0700 Subject: [CPUFREQ] allow ondemand and conservative cpufreq governors to be used as default Depending on the transition latency of the HW for cpufreq switches, the ondemand or conservative governor cannot be used with certain cpufreq drivers. Still the ondemand should be the default governor on a wide range of systems. This patch allows this and lets the governor fallback to the performance governor at cpufreq driver load time, if the driver does not support fast enough frequency switching. Main benefit is that on e.g. installation or other systems without userspace support a working dynamic cpufreq support can be achieved on most systems by simply loading the cpufreq driver. This is especially essential for recent x86(_64) laptop hardware which may rely on working dynamic cpufreq OS support. Signed-off-by: Thomas Renninger Signed-off-by: Venkatesh Pallipadi Cc: Russell King Cc: Bryan Wu Cc: Andi Kleen Cc: "Luck, Tony" Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Paul Mundt Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Dave Jones --- drivers/cpufreq/Kconfig | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-) (limited to 'drivers/cpufreq/Kconfig') diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig index 993fa7b89253..721f86f4f008 100644 --- a/drivers/cpufreq/Kconfig +++ b/drivers/cpufreq/Kconfig @@ -56,10 +56,6 @@ config CPU_FREQ_STAT_DETAILS If in doubt, say N. -# 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" default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110 @@ -85,6 +81,29 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE program shall be able to set the CPU dynamically without having to enable the userspace governor manually. +config CPU_FREQ_DEFAULT_GOV_ONDEMAND + bool "ondemand" + select CPU_FREQ_GOV_ONDEMAND + select CPU_FREQ_GOV_PERFORMANCE + help + Use the CPUFreq governor 'ondemand' as default. This allows + you to get a full dynamic frequency capable system by simply + loading your cpufreq low-level hardware driver. + Be aware that not all cpufreq drivers support the ondemand + governor. If unsure have a look at the help section of the + driver. Fallback governor will be the performance governor. + +config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE + bool "conservative" + select CPU_FREQ_GOV_CONSERVATIVE + select CPU_FREQ_GOV_PERFORMANCE + help + Use the CPUFreq governor 'conservative' as default. This allows + you to get a full dynamic frequency capable system by simply + loading your cpufreq low-level hardware driver. + Be aware that not all cpufreq drivers support the conservative + governor. If unsure have a look at the help section of the + driver. Fallback governor will be the performance governor. endchoice config CPU_FREQ_GOV_PERFORMANCE -- cgit v1.2.3