When the userspace governor is used, the user intends to set a fixed CPU
frequency for a policy, for whatever reason. The CPUFREQ_GOV_STRICT_TARGET
flag is the required behaviour. Without this flag, the intel_pstate driver,
with HWP enabled, will set HWP_MIN_PERF to the target frequency and HWP_MAX_PERF
to the policy maximum, when configuring the HWP_REQUEST MSR. This lets the
hardware choose any frequency between the target frequency and the policy
maximum, which is not the intended behaviour. To fix this,
`cat scaling_setspeed > scaling_max_freq` had to be done. With this patch, that
is no longer necessary. Setting scaling_setspeed is sufficient, as expected.
Signed-off-by: Shashank Balaji <shashank.mahadasyam@xxxxxxxx>
---
drivers/cpufreq/cpufreq_userspace.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
index 2c42fee76daa808f0cd1c7b1ab85476e695082e9..77d62152cd386d0eea69eba347b39f055ec860ce 100644
--- a/drivers/cpufreq/cpufreq_userspace.c
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -134,6 +134,7 @@ static struct cpufreq_governor cpufreq_gov_userspace = {
.store_setspeed = cpufreq_set,
.show_setspeed = show_speed,
.owner = THIS_MODULE,
+ .flags = CPUFREQ_GOV_STRICT_TARGET,
};
MODULE_AUTHOR("Dominik Brodowski <linux@xxxxxxxx>, "
--
2.43.0
