[v5,4/6] soc: qcom: Extend RPMh power controller driver to register warming devices.
diff mbox series

Message ID 20200320014107.26087-5-thara.gopinath@linaro.org
State Changes Requested, archived
Headers show
Series
  • Introduce Power domain based warming device driver
Related show

Commit Message

Thara Gopinath March 20, 2020, 1:41 a.m. UTC
RPMh power control hosts power domains that can be used as
thermal warming devices. Register these power domains
with the generic power domain warming device thermal framework.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---

v3->v4:
	- Introduce a boolean value is_warming_dev in rpmhpd structure to
	  indicate if a generic power domain can be used as a warming
	  device or not.With this change, device tree no longer has to
	  specify which power domain inside the rpmh power domain provider
	  is a warming device.
	- Move registering of warming devices into a late initcall to
	  ensure that warming devices are registered after thermal
	  framework is initialized.

 drivers/soc/qcom/rpmhpd.c | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

Comments

Bjorn Andersson March 27, 2020, 10:53 p.m. UTC | #1
On Thu 19 Mar 18:41 PDT 2020, Thara Gopinath wrote:

> RPMh power control hosts power domains that can be used as
> thermal warming devices. Register these power domains
> with the generic power domain warming device thermal framework.
> 
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
> ---
> 
> v3->v4:
> 	- Introduce a boolean value is_warming_dev in rpmhpd structure to
> 	  indicate if a generic power domain can be used as a warming
> 	  device or not.With this change, device tree no longer has to
> 	  specify which power domain inside the rpmh power domain provider
> 	  is a warming device.
> 	- Move registering of warming devices into a late initcall to
> 	  ensure that warming devices are registered after thermal
> 	  framework is initialized.

This information is lost when we merge patches, as such I would like
such design decisions to be described in the commit message itself.
But...

> 
>  drivers/soc/qcom/rpmhpd.c | 37 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c
> index 7142409a3b77..4e9c0bbb8826 100644
> --- a/drivers/soc/qcom/rpmhpd.c
> +++ b/drivers/soc/qcom/rpmhpd.c
> @@ -11,6 +11,7 @@
>  #include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_opp.h>
> +#include <linux/pd_warming.h>
>  #include <soc/qcom/cmd-db.h>
>  #include <soc/qcom/rpmh.h>
>  #include <dt-bindings/power/qcom-rpmpd.h>
> @@ -48,6 +49,7 @@ struct rpmhpd {
>  	bool		enabled;
>  	const char	*res_name;
>  	u32		addr;
> +	bool		is_warming_dev;
>  };
>  
>  struct rpmhpd_desc {
> @@ -55,6 +57,8 @@ struct rpmhpd_desc {
>  	size_t num_pds;
>  };
>  
> +const struct rpmhpd_desc *global_desc;
> +
>  static DEFINE_MUTEX(rpmhpd_lock);
>  
>  /* SDM845 RPMH powerdomains */
> @@ -89,6 +93,7 @@ static struct rpmhpd sdm845_mx = {
>  	.pd = { .name = "mx", },
>  	.peer = &sdm845_mx_ao,
>  	.res_name = "mx.lvl",
> +	.is_warming_dev = true,
>  };
>  
>  static struct rpmhpd sdm845_mx_ao = {
> @@ -452,7 +457,14 @@ static int rpmhpd_probe(struct platform_device *pdev)
>  					       &rpmhpds[i]->pd);
>  	}
>  
> -	return of_genpd_add_provider_onecell(pdev->dev.of_node, data);
> +	ret = of_genpd_add_provider_onecell(pdev->dev.of_node, data);
> +
> +	if (ret)
> +		return ret;
> +
> +	global_desc = desc;
> +
> +	return 0;
>  }
>  
>  static struct platform_driver rpmhpd_driver = {
> @@ -469,3 +481,26 @@ static int __init rpmhpd_init(void)
>  	return platform_driver_register(&rpmhpd_driver);
>  }
>  core_initcall(rpmhpd_init);
> +
> +static int __init rpmhpd_init_warming_device(void)
> +{
> +	size_t num_pds;
> +	struct rpmhpd **rpmhpds;
> +	int i;
> +
> +	if (!global_desc)
> +		return -EINVAL;
> +
> +	rpmhpds = global_desc->rpmhpds;
> +	num_pds = global_desc->num_pds;
> +
> +	if (!of_find_property(rpmhpds[0]->dev->of_node, "#cooling-cells", NULL))
> +		return 0;
> +
> +	for (i = 0; i < num_pds; i++)
> +		if (rpmhpds[i]->is_warming_dev)
> +			of_pd_warming_register(rpmhpds[i]->dev, i);
> +
> +	return 0;
> +}
> +late_initcall(rpmhpd_init_warming_device);

...why can't this be done in rpmhpd_probe()?

In particular with the recent patches from John Stultz to allow rpmhpd
to be built as a module I don't think there's any guarantees that
rpmh_probe() will have succeeded before rpmhpd_init_warming_device()
executes.

Regards,
Bjorn
Thara Gopinath March 30, 2020, 2:53 p.m. UTC | #2
On 3/27/20 6:53 PM, Bjorn Andersson wrote:
> On Thu 19 Mar 18:41 PDT 2020, Thara Gopinath wrote:
> 
>> RPMh power control hosts power domains that can be used as
>> thermal warming devices. Register these power domains
>> with the generic power domain warming device thermal framework.
>>
>> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
>> Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
>> ---
>>
>> v3->v4:
>> 	- Introduce a boolean value is_warming_dev in rpmhpd structure to
>> 	  indicate if a generic power domain can be used as a warming
>> 	  device or not.With this change, device tree no longer has to
>> 	  specify which power domain inside the rpmh power domain provider
>> 	  is a warming device.
>> 	- Move registering of warming devices into a late initcall to
>> 	  ensure that warming devices are registered after thermal
>> 	  framework is initialized.
> 
> This information is lost when we merge patches, as such I would like
> such design decisions to be described in the commit message itself.
> But...
> 
>>
>>   drivers/soc/qcom/rpmhpd.c | 37 ++++++++++++++++++++++++++++++++++++-
>>   1 file changed, 36 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c
>> index 7142409a3b77..4e9c0bbb8826 100644
>> --- a/drivers/soc/qcom/rpmhpd.c
>> +++ b/drivers/soc/qcom/rpmhpd.c
>> @@ -11,6 +11,7 @@
>>   #include <linux/of_device.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/pm_opp.h>
>> +#include <linux/pd_warming.h>
>>   #include <soc/qcom/cmd-db.h>
>>   #include <soc/qcom/rpmh.h>
>>   #include <dt-bindings/power/qcom-rpmpd.h>
>> @@ -48,6 +49,7 @@ struct rpmhpd {
>>   	bool		enabled;
>>   	const char	*res_name;
>>   	u32		addr;
>> +	bool		is_warming_dev;
>>   };
>>   
>>   struct rpmhpd_desc {
>> @@ -55,6 +57,8 @@ struct rpmhpd_desc {
>>   	size_t num_pds;
>>   };
>>   
>> +const struct rpmhpd_desc *global_desc;
>> +
>>   static DEFINE_MUTEX(rpmhpd_lock);
>>   
>>   /* SDM845 RPMH powerdomains */
>> @@ -89,6 +93,7 @@ static struct rpmhpd sdm845_mx = {
>>   	.pd = { .name = "mx", },
>>   	.peer = &sdm845_mx_ao,
>>   	.res_name = "mx.lvl",
>> +	.is_warming_dev = true,
>>   };
>>   
>>   static struct rpmhpd sdm845_mx_ao = {
>> @@ -452,7 +457,14 @@ static int rpmhpd_probe(struct platform_device *pdev)
>>   					       &rpmhpds[i]->pd);
>>   	}
>>   
>> -	return of_genpd_add_provider_onecell(pdev->dev.of_node, data);
>> +	ret = of_genpd_add_provider_onecell(pdev->dev.of_node, data);
>> +
>> +	if (ret)
>> +		return ret;
>> +
>> +	global_desc = desc;
>> +
>> +	return 0;
>>   }
>>   
>>   static struct platform_driver rpmhpd_driver = {
>> @@ -469,3 +481,26 @@ static int __init rpmhpd_init(void)
>>   	return platform_driver_register(&rpmhpd_driver);
>>   }
>>   core_initcall(rpmhpd_init);
>> +
>> +static int __init rpmhpd_init_warming_device(void)
>> +{
>> +	size_t num_pds;
>> +	struct rpmhpd **rpmhpds;
>> +	int i;
>> +
>> +	if (!global_desc)
>> +		return -EINVAL;
>> +
>> +	rpmhpds = global_desc->rpmhpds;
>> +	num_pds = global_desc->num_pds;
>> +
>> +	if (!of_find_property(rpmhpds[0]->dev->of_node, "#cooling-cells", NULL))
>> +		return 0;
>> +
>> +	for (i = 0; i < num_pds; i++)
>> +		if (rpmhpds[i]->is_warming_dev)
>> +			of_pd_warming_register(rpmhpds[i]->dev, i);
>> +
>> +	return 0;
>> +}
>> +late_initcall(rpmhpd_init_warming_device);
> 
> ...why can't this be done in rpmhpd_probe()?
> 
> In particular with the recent patches from John Stultz to allow rpmhpd
> to be built as a module I don't think there's any guarantees that
> rpmh_probe() will have succeeded before rpmhpd_init_warming_device()
> executes.

It is to take care of boot order.
So this has to happen after the thermal framework is initialized. 
Thermal framework is initialized with core_initcall. Can I move the 
rpmhpd init as a postcore_initcall ? Then I can get rid of this separate 
function and keep it as part of probe.

> 
> Regards,
> Bjorn
>
Bjorn Andersson March 30, 2020, 10:29 p.m. UTC | #3
On Mon 30 Mar 07:53 PDT 2020, Thara Gopinath wrote:
> On 3/27/20 6:53 PM, Bjorn Andersson wrote:
> > On Thu 19 Mar 18:41 PDT 2020, Thara Gopinath wrote:
[..]
> > > +static int __init rpmhpd_init_warming_device(void)
> > > +{
> > > +	size_t num_pds;
> > > +	struct rpmhpd **rpmhpds;
> > > +	int i;
> > > +
> > > +	if (!global_desc)
> > > +		return -EINVAL;
> > > +
> > > +	rpmhpds = global_desc->rpmhpds;
> > > +	num_pds = global_desc->num_pds;
> > > +
> > > +	if (!of_find_property(rpmhpds[0]->dev->of_node, "#cooling-cells", NULL))
> > > +		return 0;
> > > +
> > > +	for (i = 0; i < num_pds; i++)
> > > +		if (rpmhpds[i]->is_warming_dev)
> > > +			of_pd_warming_register(rpmhpds[i]->dev, i);
> > > +
> > > +	return 0;
> > > +}
> > > +late_initcall(rpmhpd_init_warming_device);
> > 
> > ...why can't this be done in rpmhpd_probe()?
> > 
> > In particular with the recent patches from John Stultz to allow rpmhpd
> > to be built as a module I don't think there's any guarantees that
> > rpmh_probe() will have succeeded before rpmhpd_init_warming_device()
> > executes.
> 
> It is to take care of boot order.

Understood.

> So this has to happen after the thermal framework is initialized. Thermal
> framework is initialized with core_initcall. Can I move the rpmhpd init as a
> postcore_initcall ? Then I can get rid of this separate function and keep it
> as part of probe.
> 

So I presume the problem is that if this is called from probe, you might
of_pd_warming_register(), which ends up in
__thermal_cooling_device_register() before thermal_init() has been
invoked? 

Which is bad because e.g. thermal_class is not yet initialized.


I don't want to rely on the order of initcalls for things to work, so
could we make this more robust by having
thermal_of_cooling_device_register() return -EPROBE_DEFER is
thermal_init() isn't done?

Regards,
Bjorn

Patch
diff mbox series

diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c
index 7142409a3b77..4e9c0bbb8826 100644
--- a/drivers/soc/qcom/rpmhpd.c
+++ b/drivers/soc/qcom/rpmhpd.c
@@ -11,6 +11,7 @@ 
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_opp.h>
+#include <linux/pd_warming.h>
 #include <soc/qcom/cmd-db.h>
 #include <soc/qcom/rpmh.h>
 #include <dt-bindings/power/qcom-rpmpd.h>
@@ -48,6 +49,7 @@  struct rpmhpd {
 	bool		enabled;
 	const char	*res_name;
 	u32		addr;
+	bool		is_warming_dev;
 };
 
 struct rpmhpd_desc {
@@ -55,6 +57,8 @@  struct rpmhpd_desc {
 	size_t num_pds;
 };
 
+const struct rpmhpd_desc *global_desc;
+
 static DEFINE_MUTEX(rpmhpd_lock);
 
 /* SDM845 RPMH powerdomains */
@@ -89,6 +93,7 @@  static struct rpmhpd sdm845_mx = {
 	.pd = { .name = "mx", },
 	.peer = &sdm845_mx_ao,
 	.res_name = "mx.lvl",
+	.is_warming_dev = true,
 };
 
 static struct rpmhpd sdm845_mx_ao = {
@@ -452,7 +457,14 @@  static int rpmhpd_probe(struct platform_device *pdev)
 					       &rpmhpds[i]->pd);
 	}
 
-	return of_genpd_add_provider_onecell(pdev->dev.of_node, data);
+	ret = of_genpd_add_provider_onecell(pdev->dev.of_node, data);
+
+	if (ret)
+		return ret;
+
+	global_desc = desc;
+
+	return 0;
 }
 
 static struct platform_driver rpmhpd_driver = {
@@ -469,3 +481,26 @@  static int __init rpmhpd_init(void)
 	return platform_driver_register(&rpmhpd_driver);
 }
 core_initcall(rpmhpd_init);
+
+static int __init rpmhpd_init_warming_device(void)
+{
+	size_t num_pds;
+	struct rpmhpd **rpmhpds;
+	int i;
+
+	if (!global_desc)
+		return -EINVAL;
+
+	rpmhpds = global_desc->rpmhpds;
+	num_pds = global_desc->num_pds;
+
+	if (!of_find_property(rpmhpds[0]->dev->of_node, "#cooling-cells", NULL))
+		return 0;
+
+	for (i = 0; i < num_pds; i++)
+		if (rpmhpds[i]->is_warming_dev)
+			of_pd_warming_register(rpmhpds[i]->dev, i);
+
+	return 0;
+}
+late_initcall(rpmhpd_init_warming_device);