OPP core allows a platform to mark OPP table as shared, when the
platform isn't using operating-points-v2 bindings.
And, so there should be a non DT way of finding out if the OPP table is
shared or not.
This patch adds dev_pm_opp_get_sharing_cpus(), which first tries to get
OPP sharing information from the opp-table (in case it is already marked
as shared), otherwise it uses the existing DT way of finding sharing
information.
Signed-off-by: Viresh Kumar <[email protected]>
---
drivers/base/power/opp/cpu.c | 45 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/pm_opp.h | 6 ++++++
2 files changed, 51 insertions(+)
diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c
index 55cbf9bd8707..9c4eb90759fb 100644
--- a/drivers/base/power/opp/cpu.c
+++ b/drivers/base/power/opp/cpu.c
@@ -329,3 +329,48 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
+
+/**
+ * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev
+ * @cpu_dev: CPU device for which we do this operation
+ * @cpumask: cpumask to update with information of sharing CPUs
+ *
+ * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
+ *
+ * Returns -ENODEV if OPP table isn't already present.
+ *
+ * Locking: The internal opp_table and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks
+ * to keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex cannot be locked.
+ */
+int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+ struct opp_device *opp_dev;
+ struct opp_table *opp_table;
+ int ret = 0;
+
+ mutex_lock(&opp_table_lock);
+
+ opp_table = _find_opp_table(cpu_dev);
+ if (IS_ERR(opp_table)) {
+ ret = PTR_ERR(opp_table);
+ goto unlock;
+ }
+
+ cpumask_clear(cpumask);
+
+ if (opp_table->shared_opp) {
+ list_for_each_entry(opp_dev, &opp_table->dev_list, node)
+ cpumask_set_cpu(opp_dev->dev->id, cpumask);
+ } else {
+ cpumask_set_cpu(cpu_dev->id, cpumask);
+ }
+
+unlock:
+ mutex_unlock(&opp_table_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 5b6ad31403a5..d6effc931013 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -66,6 +66,7 @@ int dev_pm_opp_set_regulator(struct device *dev, const char *name);
void dev_pm_opp_put_regulator(struct device *dev);
int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);
int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask);
+int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask);
#else
static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
{
@@ -184,6 +185,11 @@ static inline int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_va
return -ENOSYS;
}
+static inline int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+ return -ENOSYS;
+}
+
#endif /* CONFIG_PM_OPP */
#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)
--
2.7.1.410.g6faf27b
On 04/21, Viresh Kumar wrote:
> diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c
> index 55cbf9bd8707..9c4eb90759fb 100644
> --- a/drivers/base/power/opp/cpu.c
> +++ b/drivers/base/power/opp/cpu.c
> @@ -329,3 +329,48 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
> return ret;
> }
> EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
> +
> +/**
> + * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev
> + * @cpu_dev: CPU device for which we do this operation
> + * @cpumask: cpumask to update with information of sharing CPUs
> + *
> + * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
> + *
> + * Returns -ENODEV if OPP table isn't already present.
> + *
> + * Locking: The internal opp_table and opp structures are RCU protected.
> + * Hence this function internally uses RCU updater strategy with mutex locks
> + * to keep the integrity of the internal data structures. Callers should ensure
> + * that this function is *NOT* called under RCU protection or in contexts where
> + * mutex cannot be locked.
> + */
> +int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
Is there a reason we use cpumask_var_t instead of struct cpumask *
here? My understanding is that cpumask_var_t is for stack
declarations.
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
On 22-04-16, 15:21, Stephen Boyd wrote:
> On 04/21, Viresh Kumar wrote:
> > diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c
> > index 55cbf9bd8707..9c4eb90759fb 100644
> > --- a/drivers/base/power/opp/cpu.c
> > +++ b/drivers/base/power/opp/cpu.c
> > @@ -329,3 +329,48 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
> > return ret;
> > }
> > EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
> > +
> > +/**
> > + * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev
> > + * @cpu_dev: CPU device for which we do this operation
> > + * @cpumask: cpumask to update with information of sharing CPUs
> > + *
> > + * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
> > + *
> > + * Returns -ENODEV if OPP table isn't already present.
> > + *
> > + * Locking: The internal opp_table and opp structures are RCU protected.
> > + * Hence this function internally uses RCU updater strategy with mutex locks
> > + * to keep the integrity of the internal data structures. Callers should ensure
> > + * that this function is *NOT* called under RCU protection or in contexts where
> > + * mutex cannot be locked.
> > + */
> > +int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
>
> Is there a reason we use cpumask_var_t instead of struct cpumask *
> here? My understanding is that cpumask_var_t is for stack
> declarations.
Just because we have been using that *consistently* everywhere in cpufreq and
OPP core.
I am fine with cpumask * as well, but we should be consistent.
So, I will keep it cpumask_var_t for this patch, and lets see if we want to
change all occurrences of the same in cpufreq and OPP core.
Sounds reasonable ?
--
viresh