diff mbox series

[v4,20/20] cpufreq: scmi: add support for fast frequency switching

Message ID 1509720477-18936-21-git-send-email-sudeep.holla@arm.com
State New
Headers show
Series [v4,01/20] dt-bindings: mailbox: add support for mailbox client shared memory | expand

Commit Message

Sudeep Holla Nov. 3, 2017, 2:47 p.m. UTC
The cpufreq core provides option for drivers to implement fast_switch
callback which is invoked for frequency switching from interrupt context.

This patch adds support for fast_switch callback in SCMI cpufreq driver
by making use of polling based SCMI transfer. It also sets the flag
fast_switch_possible.

Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

---
 drivers/cpufreq/scmi-cpufreq.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

-- 
2.7.4

Comments

Sudeep Holla Nov. 7, 2017, 10:57 a.m. UTC | #1
On 07/11/17 06:19, Viresh Kumar wrote:
> On 03-11-17, 14:47, Sudeep Holla wrote:

>> The cpufreq core provides option for drivers to implement fast_switch

>> callback which is invoked for frequency switching from interrupt context.

>>

>> This patch adds support for fast_switch callback in SCMI cpufreq driver

>> by making use of polling based SCMI transfer. It also sets the flag

>> fast_switch_possible.

>>

>> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>

>> Cc: Viresh Kumar <viresh.kumar@linaro.org>

>> Cc: linux-pm@vger.kernel.org

>> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

>> ---

>>  drivers/cpufreq/scmi-cpufreq.c | 16 ++++++++++++++++

>>  1 file changed, 16 insertions(+)

>>

>> diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c

>> index b1057a13e6a7..91df5013f7b2 100644

>> --- a/drivers/cpufreq/scmi-cpufreq.c

>> +++ b/drivers/cpufreq/scmi-cpufreq.c

>> @@ -64,6 +64,19 @@ scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index)

>>  	return perf_ops->freq_set(handle, priv->domain_id, freq, false);

>>  }

>>  

>> +static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,

>> +					     unsigned int target_freq)

>> +{

>> +	struct scmi_data *priv = policy->driver_data;

>> +	struct scmi_perf_ops *perf_ops = handle->perf_ops;

>> +

>> +	if (!perf_ops->freq_set(handle, priv->domain_id,

>> +				target_freq * 1000, true))

>> +		return target_freq;

>> +

>> +	return 0;

>> +}

>> +

>>  static int

>>  scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)

>>  {

>> @@ -167,6 +180,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)

>>  

>>  	policy->cpuinfo.transition_latency = latency;

>>  

>> +	policy->fast_switch_possible = true;

>>  	return 0;

>>  

>>  out_free_cpufreq_table:

>> @@ -183,6 +197,7 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy)

>>  {

>>  	struct scmi_data *priv = policy->driver_data;

>>  

>> +	policy->fast_switch_possible = false;

> 

> You don't need this.

> 


OK, dropped now.

>>  	cpufreq_cooling_unregister(priv->cdev);

>>  	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);

>>  	kfree(priv);

>> @@ -226,6 +241,7 @@ static struct cpufreq_driver scmi_cpufreq_driver = {

>>  	.verify	= cpufreq_generic_frequency_table_verify,

>>  	.attr	= cpufreq_generic_attr,

>>  	.target_index	= scmi_cpufreq_set_target,

>> +	.fast_switch	= scmi_cpufreq_fast_switch,

>>  	.get	= scmi_cpufreq_get_rate,

>>  	.init	= scmi_cpufreq_init,

>>  	.exit	= scmi_cpufreq_exit,

> 

> Apart from that.

> 

> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

> 


Thanks

-- 
Regards,
Sudeep
Sudeep Holla Nov. 8, 2017, 3:42 p.m. UTC | #2
On 08/11/17 11:05, Arnd Bergmann wrote:
> On Wed, Nov 8, 2017 at 11:42 AM, Sudeep Holla <sudeep.holla@arm.com> wrote:

>>

>>

>> On 08/11/17 00:24, Rafael J. Wysocki wrote:

>>> On Friday, November 3, 2017 3:47:57 PM CET Sudeep Holla wrote:

>>>> The cpufreq core provides option for drivers to implement fast_switch

>>>> callback which is invoked for frequency switching from interrupt context.

>>>>

>>>> This patch adds support for fast_switch callback in SCMI cpufreq driver

>>>> by making use of polling based SCMI transfer. It also sets the flag

>>>> fast_switch_possible.

>>>>

>>>> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>

>>>> Cc: Viresh Kumar <viresh.kumar@linaro.org>

>>>> Cc: linux-pm@vger.kernel.org

>>>> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

>>>

>>> I'm assuming that this material will go in along with the rest of the series

>>> through a different tree.

>>>

>>

>> Indeed, I will ask ARM-SoC guys to take it via their tree when ready. I

>> assume you are fine with that, please provide ack if that's still the case.

> 

> Yes, that makes sense.

> 



Thanks Arnd. Thanks Rafael for the ack.

-- 
Regards,
Sudeep
diff mbox series

Patch

diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index b1057a13e6a7..91df5013f7b2 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -64,6 +64,19 @@  scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index)
 	return perf_ops->freq_set(handle, priv->domain_id, freq, false);
 }
 
+static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,
+					     unsigned int target_freq)
+{
+	struct scmi_data *priv = policy->driver_data;
+	struct scmi_perf_ops *perf_ops = handle->perf_ops;
+
+	if (!perf_ops->freq_set(handle, priv->domain_id,
+				target_freq * 1000, true))
+		return target_freq;
+
+	return 0;
+}
+
 static int
 scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
 {
@@ -167,6 +180,7 @@  static int scmi_cpufreq_init(struct cpufreq_policy *policy)
 
 	policy->cpuinfo.transition_latency = latency;
 
+	policy->fast_switch_possible = true;
 	return 0;
 
 out_free_cpufreq_table:
@@ -183,6 +197,7 @@  static int scmi_cpufreq_exit(struct cpufreq_policy *policy)
 {
 	struct scmi_data *priv = policy->driver_data;
 
+	policy->fast_switch_possible = false;
 	cpufreq_cooling_unregister(priv->cdev);
 	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
 	kfree(priv);
@@ -226,6 +241,7 @@  static struct cpufreq_driver scmi_cpufreq_driver = {
 	.verify	= cpufreq_generic_frequency_table_verify,
 	.attr	= cpufreq_generic_attr,
 	.target_index	= scmi_cpufreq_set_target,
+	.fast_switch	= scmi_cpufreq_fast_switch,
 	.get	= scmi_cpufreq_get_rate,
 	.init	= scmi_cpufreq_init,
 	.exit	= scmi_cpufreq_exit,