[PATCH V4 0/3] PM / Domains: Add initial PM clock support to genpd

[PATCH V4 0/3] PM / Domains: Add initial PM clock support to genpd

[Ulf Hansson]

Changes in v4:
	-Applied acks/tested by tags.
	-Change name of define, affects all patches.

Changes in v3:
	-Fixed comments from Rafael for patch 1.
	-Change name of define, affects all patches.

Changes in v2:
	-Small fixes in patch 1.


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 patchset 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 patchsets 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.

In patch 2 and patch 3, we convert some of the SH-MOBILE SOCs to start using the
new PM clock support in genpd.


Ulf Hansson (3):
  PM / Domains: Initial PM clock support for genpd
  ARM: shmobile: Convert to genpd flags for PM clocks for r8a7779
  ARM: shmobile: Convert to genpd flags for PM clocks for R-mobile

 arch/arm/mach-shmobile/pm-r8a7779.c | 3 +--
 arch/arm/mach-shmobile/pm-rmobile.c | 3 +--
 drivers/base/power/domain.c         | 7 +++++++
 include/linux/pm_domain.h           | 4 ++++
 4 files changed, 13 insertions(+), 4 deletions(-)

-- 
1.9.1

[PATCH V4 1/3] PM / Domains: Initial PM clock support for genpd

[Ulf Hansson]

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 GENDP_FLAG_PM_CLK bit for it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
---

Changes in v4:
	Rename define.

Changes in v3:
	Moved define out of struct definition.
	Don't use bitops.h
	Rename define to GENDP_PM_CLK.
	
Changes in v2:
	Set ->start() callback to pm_clk_resume() and fixed comment.

---
 drivers/base/power/domain.c | 7 +++++++
 include/linux/pm_domain.h   | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 735c473..6a103a3 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>
@@ -1928,6 +1929,12 @@ 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 & GENPD_FLAG_PM_CLK) {
+		genpd->dev_ops.stop = pm_clk_suspend;
+		genpd->dev_ops.start = pm_clk_resume;
+	}
+
 	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 8cbd32e..6cd20d5 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -17,6 +17,9 @@
 #include <linux/notifier.h>
 #include <linux/cpuidle.h>
 
+/* Defines used for the flags field in the struct generic_pm_domain */
+#define GENPD_FLAG_PM_CLK	(1U << 0) /* PM domain uses PM clk */
+
 enum gpd_status {
 	GPD_STATE_ACTIVE = 0,	/* PM domain is active */
 	GPD_STATE_WAIT_MASTER,	/* PM domain's master is being waited for */
@@ -76,6 +79,7 @@ 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 */
 };
 
 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
-- 
1.9.1

[PATCH V4 2/3] ARM: shmobile: Convert to genpd flags for PM clocks for r8a7779

[Ulf Hansson]

Instead of using the dev_ops ->stop|start() callbacks for genpd, let's
convert to use genpd's flag field and set it to GENPD_FLAG_PM_CLK.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
---

Changes in v4:
        Convert to renamed define.

Changes in v3:
        Convert to renamed define.

Changes in v2:
        None.
---
 arch/arm/mach-shmobile/pm-r8a7779.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm/mach-shmobile/pm-r8a7779.c b/arch/arm/mach-shmobile/pm-r8a7779.c
index 82fe3d7..44a74c4 100644
--- a/arch/arm/mach-shmobile/pm-r8a7779.c
+++ b/arch/arm/mach-shmobile/pm-r8a7779.c
@@ -83,9 +83,8 @@ static void r8a7779_init_pm_domain(struct r8a7779_pm_domain *r8a7779_pd)
 {
 	struct generic_pm_domain *genpd = &r8a7779_pd->genpd;
 
+	genpd->flags = GENPD_FLAG_PM_CLK;
 	pm_genpd_init(genpd, NULL, false);
-	genpd->dev_ops.stop = pm_clk_suspend;
-	genpd->dev_ops.start = pm_clk_resume;
 	genpd->dev_ops.active_wakeup = pd_active_wakeup;
 	genpd->power_off = pd_power_down;
 	genpd->power_on = pd_power_up;
-- 
1.9.1

[PATCH V4 3/3] ARM: shmobile: Convert to genpd flags for PM clocks for R-mobile

[Ulf Hansson]

Instead of using the dev_ops ->stop|start() callbacks for genpd, let's
convert to use genpd's flag field and set it to GENPD_FLAG_PM_CLK.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
---

Changes in v4:
        Convert to renamed define.

Changes in v3:
        Convert to renamed define.

Changes in v2:
        None.
---
 arch/arm/mach-shmobile/pm-rmobile.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm/mach-shmobile/pm-rmobile.c b/arch/arm/mach-shmobile/pm-rmobile.c
index 717e641..6f7d56e 100644
--- a/arch/arm/mach-shmobile/pm-rmobile.c
+++ b/arch/arm/mach-shmobile/pm-rmobile.c
@@ -106,9 +106,8 @@ static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
 	struct generic_pm_domain *genpd = &rmobile_pd->genpd;
 	struct dev_power_governor *gov = rmobile_pd->gov;
 
+	genpd->flags = GENPD_FLAG_PM_CLK;
 	pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
-	genpd->dev_ops.stop		= pm_clk_suspend;
-	genpd->dev_ops.start		= pm_clk_resume;
 	genpd->dev_ops.active_wakeup	= rmobile_pd_active_wakeup;
 	genpd->power_off		= rmobile_pd_power_down;
 	genpd->power_on			= rmobile_pd_power_up;
-- 
1.9.1

Re: [PATCH V4 1/3] PM / Domains: Initial PM clock support for genpd

[Kevin Hilman]

Ulf Hansson <ulf.hansson@linaro.org> writes:

> 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 GENDP_FLAG_PM_CLK bit for it.
>
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>

Acked-by: Kevin Hilman <khilman@linaro.org>

Are you also planning to add a way to enable this option from DT?

Kevin

Re: [PATCH V4 1/3] PM / Domains: Initial PM clock support for genpd

[Ulf Hansson]

On 2 December 2014 at 02:09, Kevin Hilman <khilman@kernel.org> wrote:
> Ulf Hansson <ulf.hansson@linaro.org> writes:
>
>> 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 GENDP_FLAG_PM_CLK bit for it.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
>> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Acked-by: Kevin Hilman <khilman@linaro.org>
>
> Are you also planning to add a way to enable this option from DT?

I am thinking of that, yes. Though I wanted the discussion around how
to deal with creating the PM clock lists while using PM domains to
settle first.

Kind regards
Uffe

Re: [PATCH V4 0/3] PM / Domains: Add initial PM clock support to genpd

[Rafael J. Wysocki]

On Monday, December 01, 2014 12:50:20 PM Ulf Hansson wrote:
> Changes in v4:
> 	-Applied acks/tested by tags.
> 	-Change name of define, affects all patches.
> 
> Changes in v3:
> 	-Fixed comments from Rafael for patch 1.
> 	-Change name of define, affects all patches.
> 
> Changes in v2:
> 	-Small fixes in patch 1.
> 
> 
> 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 patchset 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 patchsets 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.
> 
> In patch 2 and patch 3, we convert some of the SH-MOBILE SOCs to start using the
> new PM clock support in genpd.
> 
> 
> Ulf Hansson (3):
>   PM / Domains: Initial PM clock support for genpd
>   ARM: shmobile: Convert to genpd flags for PM clocks for r8a7779
>   ARM: shmobile: Convert to genpd flags for PM clocks for R-mobile

All queued up for 3.19-rc1, thanks!

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.