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-rw-r--r--drivers/cpufreq/cpufreq.c58
-rw-r--r--include/linux/cpufreq.h2
2 files changed, 40 insertions, 20 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 96a69c67a545..55e9795801a4 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1201,28 +1201,39 @@ static int cpufreq_online(unsigned int cpu)
return -ENOMEM;
}
- cpumask_copy(policy->cpus, cpumask_of(cpu));
+ if (!new_policy && cpufreq_driver->online) {
+ ret = cpufreq_driver->online(policy);
+ if (ret) {
+ pr_debug("%s: %d: initialization failed\n", __func__,
+ __LINE__);
+ goto out_exit_policy;
+ }
- /* call driver. From then on the cpufreq must be able
- * to accept all calls to ->verify and ->setpolicy for this CPU
- */
- ret = cpufreq_driver->init(policy);
- if (ret) {
- pr_debug("initialization failed\n");
- goto out_free_policy;
- }
+ /* Recover policy->cpus using related_cpus */
+ cpumask_copy(policy->cpus, policy->related_cpus);
+ } else {
+ cpumask_copy(policy->cpus, cpumask_of(cpu));
- ret = cpufreq_table_validate_and_sort(policy);
- if (ret)
- goto out_exit_policy;
+ /*
+ * Call driver. From then on the cpufreq must be able
+ * to accept all calls to ->verify and ->setpolicy for this CPU.
+ */
+ ret = cpufreq_driver->init(policy);
+ if (ret) {
+ pr_debug("%s: %d: initialization failed\n", __func__,
+ __LINE__);
+ goto out_free_policy;
+ }
- down_write(&policy->rwsem);
+ ret = cpufreq_table_validate_and_sort(policy);
+ if (ret)
+ goto out_exit_policy;
- if (new_policy) {
/* related_cpus should at least include policy->cpus. */
cpumask_copy(policy->related_cpus, policy->cpus);
}
+ down_write(&policy->rwsem);
/*
* affected cpus must always be the one, which are online. We aren't
* managing offline cpus here.
@@ -1421,11 +1432,12 @@ static int cpufreq_offline(unsigned int cpu)
cpufreq_exit_governor(policy);
/*
- * Perform the ->exit() even during light-weight tear-down,
- * since this is a core component, and is essential for the
- * subsequent light-weight ->init() to succeed.
+ * Perform the ->offline() during light-weight tear-down, as
+ * that allows fast recovery when the CPU comes back.
*/
- if (cpufreq_driver->exit) {
+ if (cpufreq_driver->offline) {
+ cpufreq_driver->offline(policy);
+ } else if (cpufreq_driver->exit) {
cpufreq_driver->exit(policy);
policy->freq_table = NULL;
}
@@ -1454,8 +1466,13 @@ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
cpumask_clear_cpu(cpu, policy->real_cpus);
remove_cpu_dev_symlink(policy, dev);
- if (cpumask_empty(policy->real_cpus))
+ if (cpumask_empty(policy->real_cpus)) {
+ /* We did light-weight exit earlier, do full tear down now */
+ if (cpufreq_driver->offline)
+ cpufreq_driver->exit(policy);
+
cpufreq_policy_free(policy);
+ }
}
/**
@@ -2488,7 +2505,8 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
driver_data->target) ||
(driver_data->setpolicy && (driver_data->target_index ||
driver_data->target)) ||
- (!!driver_data->get_intermediate != !!driver_data->target_intermediate))
+ (!!driver_data->get_intermediate != !!driver_data->target_intermediate) ||
+ (!driver_data->online != !driver_data->offline))
return -EINVAL;
pr_debug("trying to register driver %s\n", driver_data->name);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 9db074ecbbd7..b160e98076e3 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -325,6 +325,8 @@ struct cpufreq_driver {
/* optional */
int (*bios_limit)(int cpu, unsigned int *limit);
+ int (*online)(struct cpufreq_policy *policy);
+ int (*offline)(struct cpufreq_policy *policy);
int (*exit)(struct cpufreq_policy *policy);
void (*stop_cpu)(struct cpufreq_policy *policy);
int (*suspend)(struct cpufreq_policy *policy);