From 379480d8258056bfdbaa65e4d3f024bb5b34b52b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Mar 2016 02:51:56 +0100 Subject: cpufreq: Move governor symbols to cpufreq.h Move definitions of symbols related to transition latency and sampling rate to include/linux/cpufreq.h so they can be used by (future) goverernors located outside of drivers/cpufreq/. No functional changes. Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar --- include/linux/cpufreq.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 74f5cff..2b4f248 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -426,6 +426,20 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div, #define CPUFREQ_POLICY_POWERSAVE (1) #define CPUFREQ_POLICY_PERFORMANCE (2) +/* + * The polling frequency depends on the capability of the processor. Default + * polling frequency is 1000 times the transition latency of the processor. The + * ondemand governor will work on any processor with transition latency <= 10ms, + * using appropriate sampling rate. + * + * For CPUs with transition latency > 10ms (mostly drivers with CPUFREQ_ETERNAL) + * the ondemand governor will not work. All times here are in us (microseconds). + */ +#define MIN_SAMPLING_RATE_RATIO (2) +#define LATENCY_MULTIPLIER (1000) +#define MIN_LATENCY_MULTIPLIER (20) +#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) + /* Governor Events */ #define CPUFREQ_GOV_START 1 #define CPUFREQ_GOV_STOP 2 -- cgit v1.1