cpufreq: intel_pstate: Fix HWP on boot CPU after system resume
Commit 41cfd64cf49fc "Update frequencies of policy->cpus only from
->set_policy()" changed the way the intel_pstate driver's ->set_policy
callback updates the HWP (hardware-managed P-states) settings.
A side effect of it is that if those settings are modified on the
boot CPU during system suspend and wakeup, they will never be
restored during subsequent system resume.
To address this problem, allow cpufreq drivers that don't provide
->target or ->target_index callbacks to use ->suspend and ->resume
callbacks and add a ->resume callback to intel_pstate to restore
the HWP settings on the CPUs that belong to the given policy.
Fixes: 41cfd64cf49fc "Update frequencies of policy->cpus only from ->set_policy()"
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index e93405f..c4acfc5 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1557,21 +1557,25 @@
if (!cpufreq_driver)
return;
- if (!has_target())
+ if (!has_target() && !cpufreq_driver->suspend)
goto suspend;
pr_debug("%s: Suspending Governors\n", __func__);
for_each_active_policy(policy) {
- down_write(&policy->rwsem);
- ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
- up_write(&policy->rwsem);
+ if (has_target()) {
+ down_write(&policy->rwsem);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+ up_write(&policy->rwsem);
- if (ret)
- pr_err("%s: Failed to stop governor for policy: %p\n",
- __func__, policy);
- else if (cpufreq_driver->suspend
- && cpufreq_driver->suspend(policy))
+ if (ret) {
+ pr_err("%s: Failed to stop governor for policy: %p\n",
+ __func__, policy);
+ continue;
+ }
+ }
+
+ if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy))
pr_err("%s: Failed to suspend driver: %p\n", __func__,
policy);
}
@@ -1596,7 +1600,7 @@
cpufreq_suspended = false;
- if (!has_target())
+ if (!has_target() && !cpufreq_driver->resume)
return;
pr_debug("%s: Resuming Governors\n", __func__);
@@ -1605,7 +1609,7 @@
if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) {
pr_err("%s: Failed to resume driver: %p\n", __func__,
policy);
- } else {
+ } else if (has_target()) {
down_write(&policy->rwsem);
ret = cpufreq_start_governor(policy);
up_write(&policy->rwsem);