diff options
Diffstat (limited to 'include/linux/cpufreq.h')
| -rw-r--r-- | include/linux/cpufreq.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 74f5cfff2b52..2b4f248b8ef1 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 |