[1/3] PM / Domains: Initial PM clock support for genpd

Message ID 1416405638-18812-2-git-send-email-ulf.hansson@linaro.org
State New
Headers show

Commit Message

Ulf Hansson Nov. 19, 2014, 2 p.m.
It's quite common for PM domains to use PM clocks. Typically from SOC
specific code, the per device PM clock list is created and
pm_clk_suspend|resume() are invoked to handle clock gating/ungating.

A step towards consolidation is to integrate PM clock support into
genpd, which is what this patch does.

In this initial step, the calls to the pm_clk_suspend|resume() are
handled within genpd, but the per device PM clock list still needs to
be created from SOC specific code. It seems reasonable to have gendp to
handle that as well, but that left to future patches to address.

It's not every users of genpd that are keen on using PM clocks thus we
need to provide this a configuration option for genpd. Therefore let's
add flag field in the genpd struct to keep this information and define
a new PM_DOMAIN_PM_CLK bit can then be set at initialization.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/base/power/domain.c | 7 +++++++
 include/linux/pm_domain.h   | 3 +++
 2 files changed, 10 insertions(+)

Comments

Dmitry Torokhov Nov. 19, 2014, 5:25 p.m. | #1
On Wed, Nov 19, 2014 at 03:00:36PM +0100, Ulf Hansson wrote:
> It's quite common for PM domains to use PM clocks. Typically from SOC
> specific code, the per device PM clock list is created and
> pm_clk_suspend|resume() are invoked to handle clock gating/ungating.
> 
> A step towards consolidation is to integrate PM clock support into
> genpd, which is what this patch does.
> 
> In this initial step, the calls to the pm_clk_suspend|resume() are
> handled within genpd, but the per device PM clock list still needs to
> be created from SOC specific code. It seems reasonable to have gendp to
> handle that as well, but that left to future patches to address.
> 
> It's not every users of genpd that are keen on using PM clocks thus we
> need to provide this a configuration option for genpd. Therefore let's
> add flag field in the genpd struct to keep this information and define
> a new PM_DOMAIN_PM_CLK bit can then be set at initialization.
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 7 +++++++
>  include/linux/pm_domain.h   | 3 +++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 3989eb6..42e328c 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -12,6 +12,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_qos.h>
> +#include <linux/pm_clock.h>
>  #include <linux/slab.h>
>  #include <linux/err.h>
>  #include <linux/sched.h>
> @@ -1948,6 +1949,12 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
>  	genpd->domain.ops.complete = pm_genpd_complete;
>  	genpd->dev_ops.save_state = pm_genpd_default_save_state;
>  	genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
> +
> +	if (genpd->flags & PM_DOMAIN_PM_CLK) {
> +		genpd->dev_ops.stop = pm_clk_suspend;
> +		genpd->dev_ops.start = pm_clk_suspend;

The 2nd one is wrong.

> +	}
> +
>  	mutex_lock(&gpd_list_lock);
>  	list_add(&genpd->gpd_list_node, &gpd_list);
>  	mutex_unlock(&gpd_list_lock);
> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
> index 9d254e2..44c6931 100644
> --- a/include/linux/pm_domain.h
> +++ b/include/linux/pm_domain.h
> @@ -14,6 +14,7 @@
>  #include <linux/pm.h>
>  #include <linux/err.h>
>  #include <linux/of.h>
> +#include <linux/bitops.h>
>  #include <linux/notifier.h>
>  #include <linux/cpuidle.h>
>  
> @@ -76,6 +77,8 @@ struct generic_pm_domain {
>  			  struct device *dev);
>  	void (*detach_dev)(struct generic_pm_domain *domain,
>  			   struct device *dev);
> +	unsigned int flags;		/* Bit field of configs for genpd */
> +#define PM_DOMAIN_PM_CLK	BIT(0)	/* PM domain use PM clk */

s/use/uses ?

Are you planning on adding a separate flag for collecting clocks from OF
on attach/detach?

>  };
>  
>  static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
> -- 
> 1.9.1
> 

Thanks.
Ulf Hansson Nov. 20, 2014, 11:53 a.m. | #2
On 19 November 2014 18:25, Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> On Wed, Nov 19, 2014 at 03:00:36PM +0100, Ulf Hansson wrote:
>> It's quite common for PM domains to use PM clocks. Typically from SOC
>> specific code, the per device PM clock list is created and
>> pm_clk_suspend|resume() are invoked to handle clock gating/ungating.
>>
>> A step towards consolidation is to integrate PM clock support into
>> genpd, which is what this patch does.
>>
>> In this initial step, the calls to the pm_clk_suspend|resume() are
>> handled within genpd, but the per device PM clock list still needs to
>> be created from SOC specific code. It seems reasonable to have gendp to
>> handle that as well, but that left to future patches to address.
>>
>> It's not every users of genpd that are keen on using PM clocks thus we
>> need to provide this a configuration option for genpd. Therefore let's
>> add flag field in the genpd struct to keep this information and define
>> a new PM_DOMAIN_PM_CLK bit can then be set at initialization.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
>> ---
>>  drivers/base/power/domain.c | 7 +++++++
>>  include/linux/pm_domain.h   | 3 +++
>>  2 files changed, 10 insertions(+)
>>
>> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
>> index 3989eb6..42e328c 100644
>> --- a/drivers/base/power/domain.c
>> +++ b/drivers/base/power/domain.c
>> @@ -12,6 +12,7 @@
>>  #include <linux/pm_runtime.h>
>>  #include <linux/pm_domain.h>
>>  #include <linux/pm_qos.h>
>> +#include <linux/pm_clock.h>
>>  #include <linux/slab.h>
>>  #include <linux/err.h>
>>  #include <linux/sched.h>
>> @@ -1948,6 +1949,12 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
>>       genpd->domain.ops.complete = pm_genpd_complete;
>>       genpd->dev_ops.save_state = pm_genpd_default_save_state;
>>       genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
>> +
>> +     if (genpd->flags & PM_DOMAIN_PM_CLK) {
>> +             genpd->dev_ops.stop = pm_clk_suspend;
>> +             genpd->dev_ops.start = pm_clk_suspend;
>
> The 2nd one is wrong.

Huh, thanks for spotting this.

>
>> +     }
>> +
>>       mutex_lock(&gpd_list_lock);
>>       list_add(&genpd->gpd_list_node, &gpd_list);
>>       mutex_unlock(&gpd_list_lock);
>> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
>> index 9d254e2..44c6931 100644
>> --- a/include/linux/pm_domain.h
>> +++ b/include/linux/pm_domain.h
>> @@ -14,6 +14,7 @@
>>  #include <linux/pm.h>
>>  #include <linux/err.h>
>>  #include <linux/of.h>
>> +#include <linux/bitops.h>
>>  #include <linux/notifier.h>
>>  #include <linux/cpuidle.h>
>>
>> @@ -76,6 +77,8 @@ struct generic_pm_domain {
>>                         struct device *dev);
>>       void (*detach_dev)(struct generic_pm_domain *domain,
>>                          struct device *dev);
>> +     unsigned int flags;             /* Bit field of configs for genpd */
>> +#define PM_DOMAIN_PM_CLK     BIT(0)  /* PM domain use PM clk */
>
> s/use/uses ?
>
> Are you planning on adding a separate flag for collecting clocks from OF
> on attach/detach?

Yes, I am thinking on that approach. Do you have any suggestions around this?

Kind regards
Uffe
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Patch

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 3989eb6..42e328c 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -12,6 +12,7 @@ 
 #include <linux/pm_runtime.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_qos.h>
+#include <linux/pm_clock.h>
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/sched.h>
@@ -1948,6 +1949,12 @@  void pm_genpd_init(struct generic_pm_domain *genpd,
 	genpd->domain.ops.complete = pm_genpd_complete;
 	genpd->dev_ops.save_state = pm_genpd_default_save_state;
 	genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
+
+	if (genpd->flags & PM_DOMAIN_PM_CLK) {
+		genpd->dev_ops.stop = pm_clk_suspend;
+		genpd->dev_ops.start = pm_clk_suspend;
+	}
+
 	mutex_lock(&gpd_list_lock);
 	list_add(&genpd->gpd_list_node, &gpd_list);
 	mutex_unlock(&gpd_list_lock);
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 9d254e2..44c6931 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -14,6 +14,7 @@ 
 #include <linux/pm.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/bitops.h>
 #include <linux/notifier.h>
 #include <linux/cpuidle.h>
 
@@ -76,6 +77,8 @@  struct generic_pm_domain {
 			  struct device *dev);
 	void (*detach_dev)(struct generic_pm_domain *domain,
 			   struct device *dev);
+	unsigned int flags;		/* Bit field of configs for genpd */
+#define PM_DOMAIN_PM_CLK	BIT(0)	/* PM domain use PM clk */
 };
 
 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)