cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGET

Introduce a new governor flag, CPUFREQ_GOV_STRICT_TARGET, for the
governors that want the target frequency to be set exactly to the
given value without leaving any room for adjustments on the hardware
side and set this flag for the powersave and performance governors.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

Author: rafaeljw

drivers/cpufreq/cpufreq_performance.c

@@ -20,6 +20,7 @@ static void cpufreq_gov_performance_limits(struct cpufreq_policy *policy)
 static struct cpufreq_governor cpufreq_gov_performance = {
 	.name		= "performance",
 	.owner		= THIS_MODULE,
+	.flags		= CPUFREQ_GOV_STRICT_TARGET,
 	.limits		= cpufreq_gov_performance_limits,
 };
 

drivers/cpufreq/cpufreq_powersave.c

@@ -21,6 +21,7 @@ static struct cpufreq_governor cpufreq_gov_powersave = {
 	.name		= "powersave",
 	.limits		= cpufreq_gov_powersave_limits,
 	.owner		= THIS_MODULE,
+	.flags		= CPUFREQ_GOV_STRICT_TARGET,
 };
 
 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");

include/linux/cpufreq.h

@@ -580,6 +580,9 @@ struct cpufreq_governor {
 /* For governors which change frequency dynamically by themselves */
 #define CPUFREQ_GOV_DYNAMIC_SWITCHING	BIT(0)
 
+/* For governors wanting the target frequency to be set exactly */
+#define CPUFREQ_GOV_STRICT_TARGET	BIT(1)
+
 
 /* Pass a target to the cpufreq driver */
 unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,