[PATCH v2 2/4] cpufreq: Introduce CPUFREQ_GOV_FLAG_STRICT_TARGET

From: Rafael J. Wysocki
Date: Mon Nov 09 2020 - 11:57:26 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Introduce a new governor flag, CPUFREQ_GOV_FLAG_STRICT_TARGET, for
the govenors 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@xxxxxxxxx>
---
drivers/cpufreq/cpufreq_performance.c | 1 +
drivers/cpufreq/cpufreq_powersave.c | 1 +
include/linux/cpufreq.h | 3 +++
3 files changed, 5 insertions(+)

Index: linux-pm/drivers/cpufreq/cpufreq_performance.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_performance.c
+++ linux-pm/drivers/cpufreq/cpufreq_performance.c
@@ -20,6 +20,7 @@ static void cpufreq_gov_performance_limi
static struct cpufreq_governor cpufreq_gov_performance = {
.name = "performance",
.owner = THIS_MODULE,
+ .flags = CPUFREQ_GOV_FLAG_STRICT_TARGET,
.limits = cpufreq_gov_performance_limits,
};

Index: linux-pm/drivers/cpufreq/cpufreq_powersave.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_powersave.c
+++ linux-pm/drivers/cpufreq/cpufreq_powersave.c
@@ -21,6 +21,7 @@ static struct cpufreq_governor cpufreq_g
.name = "powersave",
.limits = cpufreq_gov_powersave_limits,
.owner = THIS_MODULE,
+ .flags = CPUFREQ_GOV_FLAG_STRICT_TARGET,
};

MODULE_AUTHOR("Dominik Brodowski <linux@xxxxxxxx>");
Index: linux-pm/include/linux/cpufreq.h
===================================================================
--- linux-pm.orig/include/linux/cpufreq.h
+++ linux-pm/include/linux/cpufreq.h
@@ -575,6 +575,9 @@ struct cpufreq_governor {
/* For governors which change frequency dynamically by themselves */
#define CPUFREQ_GOV_FLAG_DYN_SWITCH BIT(0)

+/* For governors wanting the target frequency to be set exactly */
+#define CPUFREQ_GOV_FLAG_STRICT_TARGET BIT(1)
+

/* Pass a target to the cpufreq driver */
unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,