linux-kernel - [PATCH 07/15] cpufreq: Restrict enabling boost on policies with no boost frequencies

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Message-Id: <7121e83e58bfd004d6e0d94e11e3e810b669eb51.1737707712.git.viresh.kumar@linaro.org>
Date: Fri, 24 Jan 2025 14:28:11 +0530
From: Viresh Kumar <viresh.kumar@...aro.org>
To: "Rafael J. Wysocki" <rafael@...nel.org>,
	Viresh Kumar <viresh.kumar@...aro.org>
Cc: linux-pm@...r.kernel.org,
	Vincent Guittot <vincent.guittot@...aro.org>,
	Lifeng Zheng <zhenglifeng1@...wei.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 07/15] cpufreq: Restrict enabling boost on policies with no boost frequencies

It is possible to have a scenario where not all cpufreq policies support
boost frequencies. And letting sysfs (or other parts of the kernel)
enable boost feature for that policy isn't correct.

Now that all drivers (that required a change) are updated to set the
policy->boost_supported properly, check this flag before enabling boost
feature for a policy.

Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 drivers/cpufreq/cpufreq.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 8b0754b506fa..1e6ab42b405f 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -631,6 +631,9 @@ static ssize_t store_local_boost(struct cpufreq_policy *policy,
 	if (!cpufreq_driver->boost_enabled)
 		return -EINVAL;
 
+	if (!policy->boost_supported)
+		return -EINVAL;
+
 	if (policy->boost_enabled == enable)
 		return count;
 
@@ -1586,7 +1589,8 @@ static int cpufreq_online(unsigned int cpu)
 		policy->cdev = of_cpufreq_cooling_register(policy);
 
 	/* Let the per-policy boost flag mirror the cpufreq_driver boost during init */
-	if (policy->boost_enabled != cpufreq_boost_enabled()) {
+	if (policy->boost_supported &&
+	    policy->boost_enabled != cpufreq_boost_enabled()) {
 		policy->boost_enabled = cpufreq_boost_enabled();
 		ret = cpufreq_driver->set_boost(policy, policy->boost_enabled);
 		if (ret) {
@@ -2822,6 +2826,9 @@ static int cpufreq_boost_trigger_state(int state)
 
 	cpus_read_lock();
 	for_each_active_policy(policy) {
+		if (!policy->boost_supported)
+			continue;
+
 		policy->boost_enabled = state;
 		ret = cpufreq_driver->set_boost(policy, state);
 		if (ret) {
-- 
2.31.1.272.g89b43f80a514