From 36b4bed5cd8f6e17019fa7d380e0836872c7b367 Mon Sep 17 00:00:00 2001 From: Pali Rohár Date: Thu, 16 Oct 2014 01:16:51 +0200 Subject: cpufreq: intel_pstate: Fix setting max_perf_pct in performance policy MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Code which changes policy to powersave changes also max_policy_pct based on max_freq. Code which change max_perf_pct has upper limit base on value max_policy_pct. When policy is changing from powersave back to performance then max_policy_pct is not changed. Which means that changing max_perf_pct is not possible to high values if max_freq was too low in powersave policy. Test case: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq 800000 $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 3300000 $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor performance $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 100 $ echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor $ echo 800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq $ echo 20 > /sys/devices/system/cpu/intel_pstate/max_perf_pct $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor powersave $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 800000 $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 20 $ echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor $ echo 3300000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq $ echo 100 > /sys/devices/system/cpu/intel_pstate/max_perf_pct $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor performance $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 3300000 $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 24 And now intel_pstate driver allows to set maximal value for max_perf_pct based on max_policy_pct which is 24 for previous powersave max_freq 800000. This patch will set default value for max_policy_pct when setting policy to performance so it will allow to set also max value for max_perf_pct. Signed-off-by: Pali Rohár Cc: All applicable Acked-by: Dirk Brandewie Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/cpufreq') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 0668b389c516..7547ab559a97 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -714,6 +714,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) { limits.min_perf_pct = 100; limits.min_perf = int_tofp(1); + limits.max_policy_pct = 100; limits.max_perf_pct = 100; limits.max_perf = int_tofp(1); limits.no_turbo = limits.turbo_disabled; -- cgit v1.2.3-58-ga151