[PATCH v3 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[PATCH v3 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[Marek Szyprowski]

Dear All,

This patchset adds runtime PM support to common clock framework. This is an
attempt to implement support for clock controllers, which belongs to a power
domain. This approach works surprisingly well on Exynos 4412 and 5433 SoCs,
what allowed us to solve various freeze/crash issues related to power
management.

The main idea behind this patchset is to keep clock's controller power domain
enabled every time when at least one of its clock is enabled or access to its
registers is being made. Clock controller driver (clock provider) can
supply a struct device pointer, which is the used by clock core for tracking and
managing clock's controller runtime pm state. Each clk_prepare() operation will
first call pm_runtime_get_sync() on the supplied device, while clk_unprepare()
will do pm_runtime_put() at the end.

This runtime PM feature has been tested with Exynos4412 and Exynos5433 clocks
drivers. Both have some clocks, which belongs to respective power domains and
need special handling during power on/off procedures. Till now it wasn't handled
at all, what caused various problems.

Patches for exynos 4412 and 5433 clocks drivers change the way the clock
provider is initialized. Instead of CLK_OF_DECLARE based initialization, a
complete platform device driver infrastructure is being used. This is needed to
let driver to use runtime pm feature and integrate with generic power domains.
The side-effect of this change is a delay in clock provider registeration
during system boot, so early initialized drivers might get EPROBEDEFER error
when requesting their clocks. This is an issue for IOMMU drivers, so
this patchset will be fully functional once the deferred probe for IOMMU
will be merged.

The side-effect of this patchset is the one can finally read
/sys/kernel/debug/clk/clk_summary on all Exynos4412 boards without any freeze.

If one wants to test this patchset (on Exynos4412 Trats2 device with FIMC-IS
driver), I've provided a branch with all needed patches (fixes for Exynos,
FIMC-IS driver and IOMMU deferred probe):
https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-clocks-pm-v3

Patches are based on vanilla v4.9-rc1 kernel.

Best regards
Marek Szyprowski
Samsung R&D Institute Poland

Changelog:

v3:
- Removed CLK_RUNTIME_PM flag, core now simply checks if runtime pm is enabled
  for the provided device during clock registration as suggested by Ulf
- Simplified code for exynos4412 isp clock driver registration
- Resolved some other minor issues pointed by Ulf clk core code
- Rebased onto v4.9-rc1 and new version of IOMMU deferred probe patchset

v2: https://www.spinics.net/lists/arm-kernel/msg532798.html
- Simplified clk_pm_runtime_get/put functions, removed workaround for devices
  with disabled runtime pm. Such workaround is no longer needed since commit
  4d23a5e84806b202d9231929c9507ef7cf7a0185 ("PM / Domains: Allow runtime PM
  during system PM phases").
- Added CLK_RUNTIME_PM flag to indicate clocks, for which clock core should
  call runtime pm functions. This solves problem with clocks, for which struct
  device is already registered, but no runtime pm is enabled.
- Extended commit messages according to Ulf suggestions.
- Fixed some style issues pointed by Barlomiej.

v1: http://www.spinics.net/lists/arm-kernel/msg528128.html
- initial version

Marek Szyprowski (5):
  clk: add support for runtime pm
  clock: samsung: add support for runtime pm
  clocks: exynos4x12: add runtime pm support for ISP clocks
  ARM: dts: exynos: add support for ISP power domain to exynos4x12
    clocks device
  clocks: exynos5433: add runtime pm support

 .../devicetree/bindings/clock/exynos4-clock.txt    |  22 ++
 arch/arm/boot/dts/exynos4x12.dtsi                  |   5 +
 drivers/clk/clk.c                                  | 111 +++++-
 drivers/clk/samsung/clk-exynos4.c                  | 211 +++++++----
 drivers/clk/samsung/clk-exynos5433.c               | 390 +++++++++++++++++----
 drivers/clk/samsung/clk-pll.c                      |   2 +-
 drivers/clk/samsung/clk.c                          |  12 +-
 drivers/clk/samsung/clk.h                          |   7 +
 8 files changed, 605 insertions(+), 155 deletions(-)

-- 
1.9.1

[PATCH v3 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[Marek Szyprowski]

Dear All,

This patchset adds runtime PM support to common clock framework. This is an
attempt to implement support for clock controllers, which belongs to a power
domain. This approach works surprisingly well on Exynos 4412 and 5433 SoCs,
what allowed us to solve various freeze/crash issues related to power
management.

The main idea behind this patchset is to keep clock's controller power domain
enabled every time when at least one of its clock is enabled or access to its
registers is being made. Clock controller driver (clock provider) can
supply a struct device pointer, which is the used by clock core for tracking and
managing clock's controller runtime pm state. Each clk_prepare() operation will
first call pm_runtime_get_sync() on the supplied device, while clk_unprepare()
will do pm_runtime_put() at the end.

This runtime PM feature has been tested with Exynos4412 and Exynos5433 clocks
drivers. Both have some clocks, which belongs to respective power domains and
need special handling during power on/off procedures. Till now it wasn't handled
at all, what caused various problems.

Patches for exynos 4412 and 5433 clocks drivers change the way the clock
provider is initialized. Instead of CLK_OF_DECLARE based initialization, a
complete platform device driver infrastructure is being used. This is needed to
let driver to use runtime pm feature and integrate with generic power domains.
The side-effect of this change is a delay in clock provider registeration
during system boot, so early initialized drivers might get EPROBEDEFER error
when requesting their clocks. This is an issue for IOMMU drivers, so
this patchset will be fully functional once the deferred probe for IOMMU
will be merged.

The side-effect of this patchset is the one can finally read
/sys/kernel/debug/clk/clk_summary on all Exynos4412 boards without any freeze.

If one wants to test this patchset (on Exynos4412 Trats2 device with FIMC-IS
driver), I've provided a branch with all needed patches (fixes for Exynos,
FIMC-IS driver and IOMMU deferred probe):
https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-clocks-pm-v3

Patches are based on vanilla v4.9-rc1 kernel.

Best regards
Marek Szyprowski
Samsung R&D Institute Poland

Changelog:

v3:
- Removed CLK_RUNTIME_PM flag, core now simply checks if runtime pm is enabled
  for the provided device during clock registration as suggested by Ulf
- Simplified code for exynos4412 isp clock driver registration
- Resolved some other minor issues pointed by Ulf clk core code
- Rebased onto v4.9-rc1 and new version of IOMMU deferred probe patchset

v2: https://www.spinics.net/lists/arm-kernel/msg532798.html
- Simplified clk_pm_runtime_get/put functions, removed workaround for devices
  with disabled runtime pm. Such workaround is no longer needed since commit
  4d23a5e84806b202d9231929c9507ef7cf7a0185 ("PM / Domains: Allow runtime PM
  during system PM phases").
- Added CLK_RUNTIME_PM flag to indicate clocks, for which clock core should
  call runtime pm functions. This solves problem with clocks, for which struct
  device is already registered, but no runtime pm is enabled.
- Extended commit messages according to Ulf suggestions.
- Fixed some style issues pointed by Barlomiej.

v1: http://www.spinics.net/lists/arm-kernel/msg528128.html
- initial version

Marek Szyprowski (5):
  clk: add support for runtime pm
  clock: samsung: add support for runtime pm
  clocks: exynos4x12: add runtime pm support for ISP clocks
  ARM: dts: exynos: add support for ISP power domain to exynos4x12
    clocks device
  clocks: exynos5433: add runtime pm support

 .../devicetree/bindings/clock/exynos4-clock.txt    |  22 ++
 arch/arm/boot/dts/exynos4x12.dtsi                  |   5 +
 drivers/clk/clk.c                                  | 111 +++++-
 drivers/clk/samsung/clk-exynos4.c                  | 211 +++++++----
 drivers/clk/samsung/clk-exynos5433.c               | 390 +++++++++++++++++----
 drivers/clk/samsung/clk-pll.c                      |   2 +-
 drivers/clk/samsung/clk.c                          |  12 +-
 drivers/clk/samsung/clk.h                          |   7 +
 8 files changed, 605 insertions(+), 155 deletions(-)

-- 
1.9.1

[PATCH v3 1/5] clk: add support for runtime pm

[Marek Szyprowski]

Registers for some clocks might be located in the SOC area, which are under the
power domain. To enable access to those registers respective domain has to be
turned on. Additionally, registers for such clocks will usually loose its
contents when power domain is turned off, so additional saving and restoring of
them might be needed in the clock controller driver.

This patch adds basic infrastructure in the clocks core to allow implementing
driver for such clocks under power domains. Clock provider can supply a
struct device pointer, which is the used by clock core for tracking and managing
clock's controller runtime pm state. Each clk_prepare() operation
will first call pm_runtime_get_sync() on the supplied device, while
clk_unprepare() will do pm_runtime_put() at the end.

Additional calls to pm_runtime_get/put functions are required to ensure that any
register access (like calculating/changing clock rates and unpreparing/disabling
unused clocks on boot) will be done with clock controller in runtime resumend
state.

When one wants to register clock controller, which make use of this feature, he
has to:
1. Provide a struct device to the core when registering the provider.
2. Ensure to enable runtime PM for that device before registering clocks.
3. Make sure that the runtime PM status of the controller device reflects
   the HW state.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/clk.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 101 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0fb39fe217d1..3cf202ccf5a9 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -21,6 +21,7 @@
 #include <linux/of.h>
 #include <linux/device.h>
 #include <linux/init.h>
+#include <linux/pm_runtime.h>
 #include <linux/sched.h>
 #include <linux/clkdev.h>
 
@@ -46,6 +47,7 @@ struct clk_core {
 	const struct clk_ops	*ops;
 	struct clk_hw		*hw;
 	struct module		*owner;
+	struct device		*dev;
 	struct clk_core		*parent;
 	const char		**parent_names;
 	struct clk_core		**parents;
@@ -87,6 +89,26 @@ struct clk {
 	struct hlist_node clks_node;
 };
 
+/***           runtime pm          ***/
+static int clk_pm_runtime_get(struct clk_core *core)
+{
+	int ret = 0;
+
+	if (!core->dev)
+		return 0;
+
+	ret = pm_runtime_get_sync(core->dev);
+	return ret < 0 ? ret : 0;
+}
+
+static void clk_pm_runtime_put(struct clk_core *core)
+{
+	if (!core->dev)
+		return;
+
+	pm_runtime_put(core->dev);
+}
+
 /***           locking             ***/
 static void clk_prepare_lock(void)
 {
@@ -150,6 +172,8 @@ static void clk_enable_unlock(unsigned long flags)
 
 static bool clk_core_is_prepared(struct clk_core *core)
 {
+	bool status;
+
 	/*
 	 * .is_prepared is optional for clocks that can prepare
 	 * fall back to software usage counter if it is missing
@@ -157,11 +181,20 @@ static bool clk_core_is_prepared(struct clk_core *core)
 	if (!core->ops->is_prepared)
 		return core->prepare_count;
 
-	return core->ops->is_prepared(core->hw);
+	if (clk_pm_runtime_get(core) == 0) {
+		status = core->ops->is_prepared(core->hw);
+		clk_pm_runtime_put(core);
+	} else {
+		status = false;
+	}
+
+	return status;
 }
 
 static bool clk_core_is_enabled(struct clk_core *core)
 {
+	bool status;
+
 	/*
 	 * .is_enabled is only mandatory for clocks that gate
 	 * fall back to software usage counter if .is_enabled is missing
@@ -169,7 +202,30 @@ static bool clk_core_is_enabled(struct clk_core *core)
 	if (!core->ops->is_enabled)
 		return core->enable_count;
 
-	return core->ops->is_enabled(core->hw);
+	/*
+	 * Check if clock controller's device is runtime active before
+	 * calling .is_enabled callback. If not, assume that clock is
+	 * disabled, because we might be called from atomic context, from
+	 * which pm_runtime_get() is not allowed.
+	 * This function is called mainly from clk_disable_unused_subtree,
+	 * which ensures proper runtime pm activation of controller before
+	 * taking enable spinlock, but the below check is needed if one tries
+	 * to call it from other places.
+	 */
+	if (core->dev) {
+		pm_runtime_get_noresume(core->dev);
+		if (!pm_runtime_active(core->dev)) {
+			status = false;
+			goto done;
+		}
+	}
+
+	status = core->ops->is_enabled(core->hw);
+done:
+	if (core->dev)
+		pm_runtime_put(core->dev);
+
+	return status;
 }
 
 /***    helper functions   ***/
@@ -489,6 +545,8 @@ static void clk_core_unprepare(struct clk_core *core)
 	if (core->ops->unprepare)
 		core->ops->unprepare(core->hw);
 
+	clk_pm_runtime_put(core);
+
 	trace_clk_unprepare_complete(core);
 	clk_core_unprepare(core->parent);
 }
@@ -530,10 +588,14 @@ static int clk_core_prepare(struct clk_core *core)
 		return 0;
 
 	if (core->prepare_count == 0) {
-		ret = clk_core_prepare(core->parent);
+		ret = clk_pm_runtime_get(core);
 		if (ret)
 			return ret;
 
+		ret = clk_core_prepare(core->parent);
+		if (ret)
+			goto runtime_put;
+
 		trace_clk_prepare(core);
 
 		if (core->ops->prepare)
@@ -541,15 +603,18 @@ static int clk_core_prepare(struct clk_core *core)
 
 		trace_clk_prepare_complete(core);
 
-		if (ret) {
-			clk_core_unprepare(core->parent);
-			return ret;
-		}
+		if (ret)
+			goto unprepare;
 	}
 
 	core->prepare_count++;
 
 	return 0;
+unprepare:
+	clk_core_unprepare(core->parent);
+runtime_put:
+	clk_pm_runtime_put(core);
+	return ret;
 }
 
 static int clk_core_prepare_lock(struct clk_core *core)
@@ -745,6 +810,9 @@ static void clk_unprepare_unused_subtree(struct clk_core *core)
 	if (core->flags & CLK_IGNORE_UNUSED)
 		return;
 
+	if (clk_pm_runtime_get(core))
+		return;
+
 	if (clk_core_is_prepared(core)) {
 		trace_clk_unprepare(core);
 		if (core->ops->unprepare_unused)
@@ -753,6 +821,8 @@ static void clk_unprepare_unused_subtree(struct clk_core *core)
 			core->ops->unprepare(core->hw);
 		trace_clk_unprepare_complete(core);
 	}
+
+	clk_pm_runtime_put(core);
 }
 
 static void clk_disable_unused_subtree(struct clk_core *core)
@@ -768,6 +838,9 @@ static void clk_disable_unused_subtree(struct clk_core *core)
 	if (core->flags & CLK_OPS_PARENT_ENABLE)
 		clk_core_prepare_enable(core->parent);
 
+	if (clk_pm_runtime_get(core))
+		goto unprepare_out;
+
 	flags = clk_enable_lock();
 
 	if (core->enable_count)
@@ -792,6 +865,8 @@ static void clk_disable_unused_subtree(struct clk_core *core)
 
 unlock_out:
 	clk_enable_unlock(flags);
+	clk_pm_runtime_put(core);
+unprepare_out:
 	if (core->flags & CLK_OPS_PARENT_ENABLE)
 		clk_core_disable_unprepare(core->parent);
 }
@@ -1563,6 +1638,7 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 {
 	struct clk_core *top, *fail_clk;
 	unsigned long rate = req_rate;
+	int ret = 0;
 
 	if (!core)
 		return 0;
@@ -1579,21 +1655,28 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 	if (!top)
 		return -EINVAL;
 
+	ret = clk_pm_runtime_get(core);
+	if (ret)
+		return ret;
+
 	/* notify that we are about to change rates */
 	fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
 	if (fail_clk) {
 		pr_debug("%s: failed to set %s rate\n", __func__,
 				fail_clk->name);
 		clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
-		return -EBUSY;
+		ret = -EBUSY;
+		goto err;
 	}
 
 	/* change the rates */
 	clk_change_rate(top);
 
 	core->req_rate = req_rate;
+err:
+	clk_pm_runtime_put(core);
 
-	return 0;
+	return ret;
 }
 
 /**
@@ -1824,12 +1907,16 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
 		p_rate = parent->rate;
 	}
 
+	ret = clk_pm_runtime_get(core);
+	if (ret)
+		goto out;
+
 	/* propagate PRE_RATE_CHANGE notifications */
 	ret = __clk_speculate_rates(core, p_rate);
 
 	/* abort if a driver objects */
 	if (ret & NOTIFY_STOP_MASK)
-		goto out;
+		goto runtime_put;
 
 	/* do the re-parent */
 	ret = __clk_set_parent(core, parent, p_index);
@@ -1842,6 +1929,8 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
 		__clk_recalc_accuracies(core);
 	}
 
+runtime_put:
+	clk_pm_runtime_put(core);
 out:
 	clk_prepare_unlock();
 
@@ -2549,6 +2638,8 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
 		goto fail_name;
 	}
 	core->ops = hw->init->ops;
+	if (dev && pm_runtime_enabled(dev))
+		core->dev = dev;
 	if (dev && dev->driver)
 		core->owner = dev->driver->owner;
 	core->hw = hw;
-- 
1.9.1

[PATCH v3 1/5] clk: add support for runtime pm

[Marek Szyprowski]

Registers for some clocks might be located in the SOC area, which are under the
power domain. To enable access to those registers respective domain has to be
turned on. Additionally, registers for such clocks will usually loose its
contents when power domain is turned off, so additional saving and restoring of
them might be needed in the clock controller driver.

This patch adds basic infrastructure in the clocks core to allow implementing
driver for such clocks under power domains. Clock provider can supply a
struct device pointer, which is the used by clock core for tracking and managing
clock's controller runtime pm state. Each clk_prepare() operation
will first call pm_runtime_get_sync() on the supplied device, while
clk_unprepare() will do pm_runtime_put() at the end.

Additional calls to pm_runtime_get/put functions are required to ensure that any
register access (like calculating/changing clock rates and unpreparing/disabling
unused clocks on boot) will be done with clock controller in runtime resumend
state.

When one wants to register clock controller, which make use of this feature, he
has to:
1. Provide a struct device to the core when registering the provider.
2. Ensure to enable runtime PM for that device before registering clocks.
3. Make sure that the runtime PM status of the controller device reflects
   the HW state.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/clk.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 101 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0fb39fe217d1..3cf202ccf5a9 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -21,6 +21,7 @@
 #include <linux/of.h>
 #include <linux/device.h>
 #include <linux/init.h>
+#include <linux/pm_runtime.h>
 #include <linux/sched.h>
 #include <linux/clkdev.h>
 
@@ -46,6 +47,7 @@ struct clk_core {
 	const struct clk_ops	*ops;
 	struct clk_hw		*hw;
 	struct module		*owner;
+	struct device		*dev;
 	struct clk_core		*parent;
 	const char		**parent_names;
 	struct clk_core		**parents;
@@ -87,6 +89,26 @@ struct clk {
 	struct hlist_node clks_node;
 };
 
+/***           runtime pm          ***/
+static int clk_pm_runtime_get(struct clk_core *core)
+{
+	int ret = 0;
+
+	if (!core->dev)
+		return 0;
+
+	ret = pm_runtime_get_sync(core->dev);
+	return ret < 0 ? ret : 0;
+}
+
+static void clk_pm_runtime_put(struct clk_core *core)
+{
+	if (!core->dev)
+		return;
+
+	pm_runtime_put(core->dev);
+}
+
 /***           locking             ***/
 static void clk_prepare_lock(void)
 {
@@ -150,6 +172,8 @@ static void clk_enable_unlock(unsigned long flags)
 
 static bool clk_core_is_prepared(struct clk_core *core)
 {
+	bool status;
+
 	/*
 	 * .is_prepared is optional for clocks that can prepare
 	 * fall back to software usage counter if it is missing
@@ -157,11 +181,20 @@ static bool clk_core_is_prepared(struct clk_core *core)
 	if (!core->ops->is_prepared)
 		return core->prepare_count;
 
-	return core->ops->is_prepared(core->hw);
+	if (clk_pm_runtime_get(core) == 0) {
+		status = core->ops->is_prepared(core->hw);
+		clk_pm_runtime_put(core);
+	} else {
+		status = false;
+	}
+
+	return status;
 }
 
 static bool clk_core_is_enabled(struct clk_core *core)
 {
+	bool status;
+
 	/*
 	 * .is_enabled is only mandatory for clocks that gate
 	 * fall back to software usage counter if .is_enabled is missing
@@ -169,7 +202,30 @@ static bool clk_core_is_enabled(struct clk_core *core)
 	if (!core->ops->is_enabled)
 		return core->enable_count;
 
-	return core->ops->is_enabled(core->hw);
+	/*
+	 * Check if clock controller's device is runtime active before
+	 * calling .is_enabled callback. If not, assume that clock is
+	 * disabled, because we might be called from atomic context, from
+	 * which pm_runtime_get() is not allowed.
+	 * This function is called mainly from clk_disable_unused_subtree,
+	 * which ensures proper runtime pm activation of controller before
+	 * taking enable spinlock, but the below check is needed if one tries
+	 * to call it from other places.
+	 */
+	if (core->dev) {
+		pm_runtime_get_noresume(core->dev);
+		if (!pm_runtime_active(core->dev)) {
+			status = false;
+			goto done;
+		}
+	}
+
+	status = core->ops->is_enabled(core->hw);
+done:
+	if (core->dev)
+		pm_runtime_put(core->dev);
+
+	return status;
 }
 
 /***    helper functions   ***/
@@ -489,6 +545,8 @@ static void clk_core_unprepare(struct clk_core *core)
 	if (core->ops->unprepare)
 		core->ops->unprepare(core->hw);
 
+	clk_pm_runtime_put(core);
+
 	trace_clk_unprepare_complete(core);
 	clk_core_unprepare(core->parent);
 }
@@ -530,10 +588,14 @@ static int clk_core_prepare(struct clk_core *core)
 		return 0;
 
 	if (core->prepare_count == 0) {
-		ret = clk_core_prepare(core->parent);
+		ret = clk_pm_runtime_get(core);
 		if (ret)
 			return ret;
 
+		ret = clk_core_prepare(core->parent);
+		if (ret)
+			goto runtime_put;
+
 		trace_clk_prepare(core);
 
 		if (core->ops->prepare)
@@ -541,15 +603,18 @@ static int clk_core_prepare(struct clk_core *core)
 
 		trace_clk_prepare_complete(core);
 
-		if (ret) {
-			clk_core_unprepare(core->parent);
-			return ret;
-		}
+		if (ret)
+			goto unprepare;
 	}
 
 	core->prepare_count++;
 
 	return 0;
+unprepare:
+	clk_core_unprepare(core->parent);
+runtime_put:
+	clk_pm_runtime_put(core);
+	return ret;
 }
 
 static int clk_core_prepare_lock(struct clk_core *core)
@@ -745,6 +810,9 @@ static void clk_unprepare_unused_subtree(struct clk_core *core)
 	if (core->flags & CLK_IGNORE_UNUSED)
 		return;
 
+	if (clk_pm_runtime_get(core))
+		return;
+
 	if (clk_core_is_prepared(core)) {
 		trace_clk_unprepare(core);
 		if (core->ops->unprepare_unused)
@@ -753,6 +821,8 @@ static void clk_unprepare_unused_subtree(struct clk_core *core)
 			core->ops->unprepare(core->hw);
 		trace_clk_unprepare_complete(core);
 	}
+
+	clk_pm_runtime_put(core);
 }
 
 static void clk_disable_unused_subtree(struct clk_core *core)
@@ -768,6 +838,9 @@ static void clk_disable_unused_subtree(struct clk_core *core)
 	if (core->flags & CLK_OPS_PARENT_ENABLE)
 		clk_core_prepare_enable(core->parent);
 
+	if (clk_pm_runtime_get(core))
+		goto unprepare_out;
+
 	flags = clk_enable_lock();
 
 	if (core->enable_count)
@@ -792,6 +865,8 @@ static void clk_disable_unused_subtree(struct clk_core *core)
 
 unlock_out:
 	clk_enable_unlock(flags);
+	clk_pm_runtime_put(core);
+unprepare_out:
 	if (core->flags & CLK_OPS_PARENT_ENABLE)
 		clk_core_disable_unprepare(core->parent);
 }
@@ -1563,6 +1638,7 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 {
 	struct clk_core *top, *fail_clk;
 	unsigned long rate = req_rate;
+	int ret = 0;
 
 	if (!core)
 		return 0;
@@ -1579,21 +1655,28 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 	if (!top)
 		return -EINVAL;
 
+	ret = clk_pm_runtime_get(core);
+	if (ret)
+		return ret;
+
 	/* notify that we are about to change rates */
 	fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
 	if (fail_clk) {
 		pr_debug("%s: failed to set %s rate\n", __func__,
 				fail_clk->name);
 		clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
-		return -EBUSY;
+		ret = -EBUSY;
+		goto err;
 	}
 
 	/* change the rates */
 	clk_change_rate(top);
 
 	core->req_rate = req_rate;
+err:
+	clk_pm_runtime_put(core);
 
-	return 0;
+	return ret;
 }
 
 /**
@@ -1824,12 +1907,16 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
 		p_rate = parent->rate;
 	}
 
+	ret = clk_pm_runtime_get(core);
+	if (ret)
+		goto out;
+
 	/* propagate PRE_RATE_CHANGE notifications */
 	ret = __clk_speculate_rates(core, p_rate);
 
 	/* abort if a driver objects */
 	if (ret & NOTIFY_STOP_MASK)
-		goto out;
+		goto runtime_put;
 
 	/* do the re-parent */
 	ret = __clk_set_parent(core, parent, p_index);
@@ -1842,6 +1929,8 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
 		__clk_recalc_accuracies(core);
 	}
 
+runtime_put:
+	clk_pm_runtime_put(core);
 out:
 	clk_prepare_unlock();
 
@@ -2549,6 +2638,8 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
 		goto fail_name;
 	}
 	core->ops = hw->init->ops;
+	if (dev && pm_runtime_enabled(dev))
+		core->dev = dev;
 	if (dev && dev->driver)
 		core->owner = dev->driver->owner;
 	core->hw = hw;
-- 
1.9.1

[PATCH v3 2/5] clock: samsung: add support for runtime pm

[Marek Szyprowski]

This patch adds struct device pointer to samsung_clk_provider and forwarding it
to clk_register_* functions, so drivers can register clocks, which use runtime
pm feature.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/samsung/clk-pll.c |  2 +-
 drivers/clk/samsung/clk.c     | 12 ++++++------
 drivers/clk/samsung/clk.h     |  1 +
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index 9617825daabb..f5249a7e545d 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -1345,7 +1345,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	pll->lock_reg = base + pll_clk->lock_offset;
 	pll->con_reg = base + pll_clk->con_offset;
 
-	clk = clk_register(NULL, &pll->hw);
+	clk = clk_register(ctx->dev, &pll->hw);
 	if (IS_ERR(clk)) {
 		pr_err("%s: failed to register pll clock %s : %ld\n",
 			__func__, pll_clk->name, PTR_ERR(clk));
diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
index b7d87d6db9dc..e6923714f024 100644
--- a/drivers/clk/samsung/clk.c
+++ b/drivers/clk/samsung/clk.c
@@ -143,7 +143,7 @@ void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_fixed_rate(NULL, list->name,
+		clk = clk_register_fixed_rate(ctx->dev, list->name,
 			list->parent_name, list->flags, list->fixed_rate);
 		if (IS_ERR(clk)) {
 			pr_err("%s: failed to register clock %s\n", __func__,
@@ -172,7 +172,7 @@ void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx,
 	unsigned int idx;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_fixed_factor(NULL, list->name,
+		clk = clk_register_fixed_factor(ctx->dev, list->name,
 			list->parent_name, list->flags, list->mult, list->div);
 		if (IS_ERR(clk)) {
 			pr_err("%s: failed to register clock %s\n", __func__,
@@ -193,7 +193,7 @@ void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_mux(NULL, list->name, list->parent_names,
+		clk = clk_register_mux(ctx->dev, list->name, list->parent_names,
 			list->num_parents, list->flags,
 			ctx->reg_base + list->offset,
 			list->shift, list->width, list->mux_flags, &ctx->lock);
@@ -226,13 +226,13 @@ void __init samsung_clk_register_div(struct samsung_clk_provider *ctx,
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
 		if (list->table)
-			clk = clk_register_divider_table(NULL, list->name,
+			clk = clk_register_divider_table(ctx->dev, list->name,
 				list->parent_name, list->flags,
 				ctx->reg_base + list->offset,
 				list->shift, list->width, list->div_flags,
 				list->table, &ctx->lock);
 		else
-			clk = clk_register_divider(NULL, list->name,
+			clk = clk_register_divider(ctx->dev, list->name,
 				list->parent_name, list->flags,
 				ctx->reg_base + list->offset, list->shift,
 				list->width, list->div_flags, &ctx->lock);
@@ -264,7 +264,7 @@ void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_gate(NULL, list->name, list->parent_name,
+		clk = clk_register_gate(ctx->dev, list->name, list->parent_name,
 				list->flags, ctx->reg_base + list->offset,
 				list->bit_idx, list->gate_flags, &ctx->lock);
 		if (IS_ERR(clk)) {
diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h
index da3bdebabf1e..9263d8a27c6b 100644
--- a/drivers/clk/samsung/clk.h
+++ b/drivers/clk/samsung/clk.h
@@ -26,6 +26,7 @@
  */
 struct samsung_clk_provider {
 	void __iomem *reg_base;
+	struct device *dev;
 	struct clk_onecell_data clk_data;
 	spinlock_t lock;
 };
-- 
1.9.1

[PATCH v3 2/5] clock: samsung: add support for runtime pm

[Marek Szyprowski]

This patch adds struct device pointer to samsung_clk_provider and forwarding it
to clk_register_* functions, so drivers can register clocks, which use runtime
pm feature.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/samsung/clk-pll.c |  2 +-
 drivers/clk/samsung/clk.c     | 12 ++++++------
 drivers/clk/samsung/clk.h     |  1 +
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index 9617825daabb..f5249a7e545d 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -1345,7 +1345,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	pll->lock_reg = base + pll_clk->lock_offset;
 	pll->con_reg = base + pll_clk->con_offset;
 
-	clk = clk_register(NULL, &pll->hw);
+	clk = clk_register(ctx->dev, &pll->hw);
 	if (IS_ERR(clk)) {
 		pr_err("%s: failed to register pll clock %s : %ld\n",
 			__func__, pll_clk->name, PTR_ERR(clk));
diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
index b7d87d6db9dc..e6923714f024 100644
--- a/drivers/clk/samsung/clk.c
+++ b/drivers/clk/samsung/clk.c
@@ -143,7 +143,7 @@ void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_fixed_rate(NULL, list->name,
+		clk = clk_register_fixed_rate(ctx->dev, list->name,
 			list->parent_name, list->flags, list->fixed_rate);
 		if (IS_ERR(clk)) {
 			pr_err("%s: failed to register clock %s\n", __func__,
@@ -172,7 +172,7 @@ void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx,
 	unsigned int idx;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_fixed_factor(NULL, list->name,
+		clk = clk_register_fixed_factor(ctx->dev, list->name,
 			list->parent_name, list->flags, list->mult, list->div);
 		if (IS_ERR(clk)) {
 			pr_err("%s: failed to register clock %s\n", __func__,
@@ -193,7 +193,7 @@ void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_mux(NULL, list->name, list->parent_names,
+		clk = clk_register_mux(ctx->dev, list->name, list->parent_names,
 			list->num_parents, list->flags,
 			ctx->reg_base + list->offset,
 			list->shift, list->width, list->mux_flags, &ctx->lock);
@@ -226,13 +226,13 @@ void __init samsung_clk_register_div(struct samsung_clk_provider *ctx,
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
 		if (list->table)
-			clk = clk_register_divider_table(NULL, list->name,
+			clk = clk_register_divider_table(ctx->dev, list->name,
 				list->parent_name, list->flags,
 				ctx->reg_base + list->offset,
 				list->shift, list->width, list->div_flags,
 				list->table, &ctx->lock);
 		else
-			clk = clk_register_divider(NULL, list->name,
+			clk = clk_register_divider(ctx->dev, list->name,
 				list->parent_name, list->flags,
 				ctx->reg_base + list->offset, list->shift,
 				list->width, list->div_flags, &ctx->lock);
@@ -264,7 +264,7 @@ void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx,
 	unsigned int idx, ret;
 
 	for (idx = 0; idx < nr_clk; idx++, list++) {
-		clk = clk_register_gate(NULL, list->name, list->parent_name,
+		clk = clk_register_gate(ctx->dev, list->name, list->parent_name,
 				list->flags, ctx->reg_base + list->offset,
 				list->bit_idx, list->gate_flags, &ctx->lock);
 		if (IS_ERR(clk)) {
diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h
index da3bdebabf1e..9263d8a27c6b 100644
--- a/drivers/clk/samsung/clk.h
+++ b/drivers/clk/samsung/clk.h
@@ -26,6 +26,7 @@
  */
 struct samsung_clk_provider {
 	void __iomem *reg_base;
+	struct device *dev;
 	struct clk_onecell_data clk_data;
 	spinlock_t lock;
 };
-- 
1.9.1

[PATCH v3 3/5] clocks: exynos4x12: add runtime pm support for ISP clocks

[Marek Szyprowski]

Exynos4412 clock controller contains some additional clocks for FIMC-ISP
(Camera ISP) subsystem. Registers for those clocks are partially located
in the SOC area, which belongs to ISP power domain.

This patch implements integration of ISP clocks with ISP power domain
by using runtime pm feature of clocks core. This finally solves all the
mysterious freezes in accessing ISP clocks when ISP power domain is disabled.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 .../devicetree/bindings/clock/exynos4-clock.txt    |  22 +++
 drivers/clk/samsung/clk-exynos4.c                  | 211 +++++++++++++++------
 2 files changed, 172 insertions(+), 61 deletions(-)

diff --git a/Documentation/devicetree/bindings/clock/exynos4-clock.txt b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
index f5a5b19ed3b2..429dd7e420e4 100644
--- a/Documentation/devicetree/bindings/clock/exynos4-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
@@ -41,3 +41,25 @@ Example 2: UART controller node that consumes the clock generated by the clock
 		clocks = <&clock CLK_UART2>, <&clock CLK_SCLK_UART2>;
 		clock-names = "uart", "clk_uart_baud0";
 	};
+
+Exynos4412 clock controller contains some additional clocks for FIMC-ISP
+(Camera ISP) subsystem. Registers for those clocks are partially located
+in the SOC area, which belongs to ISP power domain. To properly handle
+additional ISP clocks and their integration with power domains, an
+additional subnode "isp-clock-controller" with "samsung,exynos4412-isp-clock"
+compatible has to be defined under the main Exynos4 clock node. This subnode
+can be then used for linking with respective ISP power domain (for more
+information, see Samsung Exynos power domains bindings).
+
+Example 3: An example of a clock controller for Exynos4412 with ISP clocks.
+
+	clock: clock-controller@10030000 {
+		compatible = "samsung,exynos4412-clock";
+		reg = <0x10030000 0x20000>;
+		#clock-cells = <1>;
+
+		isp-clock-controller {
+			compatible = "samsung,exynos4412-isp-clock";
+			power-domains = <&pd_isp>;
+		};
+	};
diff --git a/drivers/clk/samsung/clk-exynos4.c b/drivers/clk/samsung/clk-exynos4.c
index faab9b31baf5..e5165be348ef 100644
--- a/drivers/clk/samsung/clk-exynos4.c
+++ b/drivers/clk/samsung/clk-exynos4.c
@@ -16,7 +16,10 @@
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_platform.h>
 #include <linux/syscore_ops.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 
 #include "clk.h"
 #include "clk-cpu.h"
@@ -123,6 +126,8 @@
 #define CLKOUT_CMU_CPU		0x14a00
 #define PWR_CTRL1		0x15020
 #define E4X12_PWR_CTRL2		0x15024
+
+/* Exynos4x12 specific registers, which belong to ISP power domain */
 #define E4X12_DIV_ISP0		0x18300
 #define E4X12_DIV_ISP1		0x18304
 #define E4X12_GATE_ISP0		0x18800
@@ -156,6 +161,8 @@ enum exynos4_plls {
 
 static void __iomem *reg_base;
 static enum exynos4_soc exynos4_soc;
+static struct samsung_clk_provider *exynos4412_ctx;
+static struct device_node *exynos4412_clk_node;
 
 /*
  * Support for CMU save/restore across system suspends
@@ -164,6 +171,7 @@ enum exynos4_plls {
 static struct samsung_clk_reg_dump *exynos4_save_common;
 static struct samsung_clk_reg_dump *exynos4_save_soc;
 static struct samsung_clk_reg_dump *exynos4_save_pll;
+static struct samsung_clk_reg_dump *exynos4x12_save_isp;
 
 /*
  * list of controller registers to be saved and restored during a
@@ -192,6 +200,13 @@ enum exynos4_plls {
 	E4X12_PWR_CTRL2,
 };
 
+static const unsigned long exynos4x12_clk_isp_save[] __initconst = {
+	E4X12_DIV_ISP0,
+	E4X12_DIV_ISP1,
+	E4X12_GATE_ISP0,
+	E4X12_GATE_ISP1,
+};
+
 static const unsigned long exynos4_clk_pll_regs[] __initconst = {
 	EPLL_LOCK,
 	VPLL_LOCK,
@@ -822,20 +837,21 @@ static void __init exynos4_clk_sleep_init(void) {}
 	DIV(0, "div_spi1_isp", "mout_spi1_isp", E4X12_DIV_ISP, 16, 4),
 	DIV(0, "div_spi1_isp_pre", "div_spi1_isp", E4X12_DIV_ISP, 20, 8),
 	DIV(0, "div_uart_isp", "mout_uart_isp", E4X12_DIV_ISP, 28, 4),
-	DIV_F(CLK_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3,
-						CLK_GET_RATE_NOCACHE, 0),
-	DIV_F(CLK_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3,
-						CLK_GET_RATE_NOCACHE, 0),
-	DIV(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3),
-	DIV_F(CLK_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp", E4X12_DIV_ISP1,
-						4, 3, CLK_GET_RATE_NOCACHE, 0),
-	DIV_F(CLK_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0", E4X12_DIV_ISP1,
-						8, 3, CLK_GET_RATE_NOCACHE, 0),
 	DIV(CLK_SCLK_FIMG2D, "sclk_fimg2d", "mout_g2d", DIV_DMC1, 0, 4),
 	DIV(CLK_DIV_C2C, "div_c2c", "mout_c2c", DIV_DMC1, 4, 3),
 	DIV(0, "div_c2c_aclk", "div_c2c", DIV_DMC1, 12, 3),
 };
 
+static struct samsung_div_clock exynos4x12_isp_div_clks[] = {
+	DIV_F(CLK_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3, 0, 0),
+	DIV_F(CLK_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3, 0, 0),
+	DIV_F(CLK_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp", E4X12_DIV_ISP1,
+						4, 3, 0, 0),
+	DIV_F(CLK_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0", E4X12_DIV_ISP1,
+						8, 3, 0, 0),
+	DIV_F(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3, 0, 0),
+};
+
 /* list of gate clocks supported in all exynos4 soc's */
 static const struct samsung_gate_clock exynos4_gate_clks[] __initconst = {
 	/*
@@ -1132,64 +1148,41 @@ static void __init exynos4_clk_sleep_init(void) {}
 			0, 0),
 	GATE(CLK_I2S0, "i2s0", "aclk100", E4X12_GATE_IP_MAUDIO, 3,
 			0, 0),
-	GATE(CLK_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
 	GATE(CLK_G2D, "g2d", "aclk200", GATE_IP_DMC, 23, 0, 0),
 	GATE(CLK_SMMU_G2D, "smmu_g2d", "aclk200", GATE_IP_DMC, 24, 0, 0),
 	GATE(CLK_TMU_APBIF, "tmu_apbif", "aclk100", E4X12_GATE_IP_PERIR, 17, 0,
 		0),
 };
 
+static struct samsung_gate_clock exynos4x12_isp_gate_clks[] = {
+	GATE(CLK_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0, 0, 0),
+	GATE(CLK_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1, 0, 0),
+	GATE(CLK_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2, 0, 0),
+	GATE(CLK_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3, 0, 0),
+	GATE(CLK_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4, 0, 0),
+	GATE(CLK_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5, 0, 0),
+	GATE(CLK_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7, 0, 0),
+	GATE(CLK_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8, 0, 0),
+	GATE(CLK_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9, 0, 0),
+	GATE(CLK_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10, 0, 0),
+	GATE(CLK_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11, 0, 0),
+	GATE(CLK_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12, 0, 0),
+	GATE(CLK_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20, 0, 0),
+	GATE(CLK_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21, 0, 0),
+	GATE(CLK_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23, 0, 0),
+	GATE(CLK_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24, 0, 0),
+	GATE(CLK_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25, 0, 0),
+	GATE(CLK_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26, 0, 0),
+	GATE(CLK_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27, 0, 0),
+	GATE(CLK_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28, 0, 0),
+	GATE(CLK_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30, 0, 0),
+	GATE(CLK_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31, 0, 0),
+	GATE(CLK_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0, 0, 0),
+	GATE(CLK_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4, 0, 0),
+	GATE(CLK_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12, 0, 0),
+	GATE(CLK_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13, 0, 0),
+};
+
 static const struct samsung_clock_alias exynos4_aliases[] __initconst = {
 	ALIAS(CLK_MOUT_CORE, NULL, "moutcore"),
 	ALIAS(CLK_ARM_CLK, NULL, "armclk"),
@@ -1438,6 +1431,100 @@ static void __init exynos4x12_core_down_clock(void)
 	{  0 },
 };
 
+static int exynos4x12_isp_clk_suspend(struct device *dev)
+{
+	samsung_clk_save(reg_base, exynos4x12_save_isp,
+				ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int exynos4x12_isp_clk_resume(struct device *dev)
+{
+	samsung_clk_restore(reg_base, exynos4x12_save_isp,
+				ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int __init exynos4x12_isp_clk_probe(struct platform_device *pdev)
+{
+	struct samsung_clk_provider *ctx = exynos4412_ctx;
+
+	if (!ctx)
+		return -ENODEV;
+
+	exynos4x12_save_isp = samsung_clk_alloc_reg_dump(exynos4x12_clk_isp_save,
+					ARRAY_SIZE(exynos4x12_clk_isp_save));
+	if (!exynos4x12_save_isp)
+		return -ENOMEM;
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	ctx->dev = &pdev->dev;
+
+	samsung_clk_register_div(ctx, exynos4x12_isp_div_clks,
+		ARRAY_SIZE(exynos4x12_isp_div_clks));
+	samsung_clk_register_gate(ctx, exynos4x12_isp_gate_clks,
+		ARRAY_SIZE(exynos4x12_isp_gate_clks));
+
+	return 0;
+}
+
+static const struct of_device_id exynos4x12_isp_clk_of_match[] = {
+	{ .compatible = "samsung,exynos4412-isp-clock", },
+	{ },
+};
+
+static const struct dev_pm_ops exynos4x12_isp_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos4x12_isp_clk_suspend,
+			   exynos4x12_isp_clk_resume, NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
+};
+
+static struct platform_driver exynos4x12_isp_clk_driver __refdata = {
+	.driver	= {
+		.name = "exynos-isp-clk",
+		.of_match_table = exynos4x12_isp_clk_of_match,
+		.suppress_bind_attrs = true,
+		.pm = &exynos4x12_isp_pm_ops,
+	},
+	.probe = exynos4x12_isp_clk_probe,
+};
+
+static int __init exynos4x12_isp_clk_init(void)
+{
+	if (!exynos4412_clk_node)
+		return 0;
+
+	of_platform_populate(exynos4412_clk_node, NULL, NULL, NULL);
+	return platform_driver_register(&exynos4x12_isp_clk_driver);
+}
+arch_initcall(exynos4x12_isp_clk_init);
+
+static void __init exynos4x12_isp_defer_clocks(struct samsung_clk_provider *ctx,
+					       struct device_node *parent)
+{
+	struct device_node *np = of_get_next_available_child(parent, NULL);
+	if (!np)
+		return;
+
+	if (of_device_is_compatible(np,
+		    exynos4x12_isp_clk_of_match[0].compatible)) {
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(exynos4x12_isp_div_clks); i++)
+			samsung_clk_add_lookup(ctx, ERR_PTR(-EPROBE_DEFER),
+					       exynos4x12_isp_div_clks[i].id);
+		for (i = 0; i < ARRAY_SIZE(exynos4x12_isp_gate_clks); i++)
+			samsung_clk_add_lookup(ctx, ERR_PTR(-EPROBE_DEFER),
+					       exynos4x12_isp_gate_clks[i].id);
+		exynos4412_ctx = ctx;
+		exynos4412_clk_node = parent;
+	}
+	of_node_put(np);
+}
+
 /* register exynos4 clocks */
 static void __init exynos4_clk_init(struct device_node *np,
 				    enum exynos4_soc soc)
@@ -1529,6 +1616,8 @@ static void __init exynos4_clk_init(struct device_node *np,
 		samsung_clk_register_fixed_factor(ctx,
 			exynos4x12_fixed_factor_clks,
 			ARRAY_SIZE(exynos4x12_fixed_factor_clks));
+		exynos4x12_isp_defer_clocks(ctx, np);
+
 		if (of_machine_is_compatible("samsung,exynos4412")) {
 			exynos_register_cpu_clock(ctx, CLK_ARM_CLK, "armclk",
 				mout_core_p4x12[0], mout_core_p4x12[1], 0x14200,
-- 
1.9.1

[PATCH v3 3/5] clocks: exynos4x12: add runtime pm support for ISP clocks

[Marek Szyprowski]

Exynos4412 clock controller contains some additional clocks for FIMC-ISP
(Camera ISP) subsystem. Registers for those clocks are partially located
in the SOC area, which belongs to ISP power domain.

This patch implements integration of ISP clocks with ISP power domain
by using runtime pm feature of clocks core. This finally solves all the
mysterious freezes in accessing ISP clocks when ISP power domain is disabled.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 .../devicetree/bindings/clock/exynos4-clock.txt    |  22 +++
 drivers/clk/samsung/clk-exynos4.c                  | 211 +++++++++++++++------
 2 files changed, 172 insertions(+), 61 deletions(-)

diff --git a/Documentation/devicetree/bindings/clock/exynos4-clock.txt b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
index f5a5b19ed3b2..429dd7e420e4 100644
--- a/Documentation/devicetree/bindings/clock/exynos4-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
@@ -41,3 +41,25 @@ Example 2: UART controller node that consumes the clock generated by the clock
 		clocks = <&clock CLK_UART2>, <&clock CLK_SCLK_UART2>;
 		clock-names = "uart", "clk_uart_baud0";
 	};
+
+Exynos4412 clock controller contains some additional clocks for FIMC-ISP
+(Camera ISP) subsystem. Registers for those clocks are partially located
+in the SOC area, which belongs to ISP power domain. To properly handle
+additional ISP clocks and their integration with power domains, an
+additional subnode "isp-clock-controller" with "samsung,exynos4412-isp-clock"
+compatible has to be defined under the main Exynos4 clock node. This subnode
+can be then used for linking with respective ISP power domain (for more
+information, see Samsung Exynos power domains bindings).
+
+Example 3: An example of a clock controller for Exynos4412 with ISP clocks.
+
+	clock: clock-controller at 10030000 {
+		compatible = "samsung,exynos4412-clock";
+		reg = <0x10030000 0x20000>;
+		#clock-cells = <1>;
+
+		isp-clock-controller {
+			compatible = "samsung,exynos4412-isp-clock";
+			power-domains = <&pd_isp>;
+		};
+	};
diff --git a/drivers/clk/samsung/clk-exynos4.c b/drivers/clk/samsung/clk-exynos4.c
index faab9b31baf5..e5165be348ef 100644
--- a/drivers/clk/samsung/clk-exynos4.c
+++ b/drivers/clk/samsung/clk-exynos4.c
@@ -16,7 +16,10 @@
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_platform.h>
 #include <linux/syscore_ops.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 
 #include "clk.h"
 #include "clk-cpu.h"
@@ -123,6 +126,8 @@
 #define CLKOUT_CMU_CPU		0x14a00
 #define PWR_CTRL1		0x15020
 #define E4X12_PWR_CTRL2		0x15024
+
+/* Exynos4x12 specific registers, which belong to ISP power domain */
 #define E4X12_DIV_ISP0		0x18300
 #define E4X12_DIV_ISP1		0x18304
 #define E4X12_GATE_ISP0		0x18800
@@ -156,6 +161,8 @@ enum exynos4_plls {
 
 static void __iomem *reg_base;
 static enum exynos4_soc exynos4_soc;
+static struct samsung_clk_provider *exynos4412_ctx;
+static struct device_node *exynos4412_clk_node;
 
 /*
  * Support for CMU save/restore across system suspends
@@ -164,6 +171,7 @@ enum exynos4_plls {
 static struct samsung_clk_reg_dump *exynos4_save_common;
 static struct samsung_clk_reg_dump *exynos4_save_soc;
 static struct samsung_clk_reg_dump *exynos4_save_pll;
+static struct samsung_clk_reg_dump *exynos4x12_save_isp;
 
 /*
  * list of controller registers to be saved and restored during a
@@ -192,6 +200,13 @@ enum exynos4_plls {
 	E4X12_PWR_CTRL2,
 };
 
+static const unsigned long exynos4x12_clk_isp_save[] __initconst = {
+	E4X12_DIV_ISP0,
+	E4X12_DIV_ISP1,
+	E4X12_GATE_ISP0,
+	E4X12_GATE_ISP1,
+};
+
 static const unsigned long exynos4_clk_pll_regs[] __initconst = {
 	EPLL_LOCK,
 	VPLL_LOCK,
@@ -822,20 +837,21 @@ static void __init exynos4_clk_sleep_init(void) {}
 	DIV(0, "div_spi1_isp", "mout_spi1_isp", E4X12_DIV_ISP, 16, 4),
 	DIV(0, "div_spi1_isp_pre", "div_spi1_isp", E4X12_DIV_ISP, 20, 8),
 	DIV(0, "div_uart_isp", "mout_uart_isp", E4X12_DIV_ISP, 28, 4),
-	DIV_F(CLK_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3,
-						CLK_GET_RATE_NOCACHE, 0),
-	DIV_F(CLK_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3,
-						CLK_GET_RATE_NOCACHE, 0),
-	DIV(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3),
-	DIV_F(CLK_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp", E4X12_DIV_ISP1,
-						4, 3, CLK_GET_RATE_NOCACHE, 0),
-	DIV_F(CLK_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0", E4X12_DIV_ISP1,
-						8, 3, CLK_GET_RATE_NOCACHE, 0),
 	DIV(CLK_SCLK_FIMG2D, "sclk_fimg2d", "mout_g2d", DIV_DMC1, 0, 4),
 	DIV(CLK_DIV_C2C, "div_c2c", "mout_c2c", DIV_DMC1, 4, 3),
 	DIV(0, "div_c2c_aclk", "div_c2c", DIV_DMC1, 12, 3),
 };
 
+static struct samsung_div_clock exynos4x12_isp_div_clks[] = {
+	DIV_F(CLK_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3, 0, 0),
+	DIV_F(CLK_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3, 0, 0),
+	DIV_F(CLK_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp", E4X12_DIV_ISP1,
+						4, 3, 0, 0),
+	DIV_F(CLK_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0", E4X12_DIV_ISP1,
+						8, 3, 0, 0),
+	DIV_F(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3, 0, 0),
+};
+
 /* list of gate clocks supported in all exynos4 soc's */
 static const struct samsung_gate_clock exynos4_gate_clks[] __initconst = {
 	/*
@@ -1132,64 +1148,41 @@ static void __init exynos4_clk_sleep_init(void) {}
 			0, 0),
 	GATE(CLK_I2S0, "i2s0", "aclk100", E4X12_GATE_IP_MAUDIO, 3,
 			0, 0),
-	GATE(CLK_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
-	GATE(CLK_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13,
-			CLK_IGNORE_UNUSED | CLK_GET_RATE_NOCACHE, 0),
 	GATE(CLK_G2D, "g2d", "aclk200", GATE_IP_DMC, 23, 0, 0),
 	GATE(CLK_SMMU_G2D, "smmu_g2d", "aclk200", GATE_IP_DMC, 24, 0, 0),
 	GATE(CLK_TMU_APBIF, "tmu_apbif", "aclk100", E4X12_GATE_IP_PERIR, 17, 0,
 		0),
 };
 
+static struct samsung_gate_clock exynos4x12_isp_gate_clks[] = {
+	GATE(CLK_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0, 0, 0),
+	GATE(CLK_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1, 0, 0),
+	GATE(CLK_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2, 0, 0),
+	GATE(CLK_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3, 0, 0),
+	GATE(CLK_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4, 0, 0),
+	GATE(CLK_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5, 0, 0),
+	GATE(CLK_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7, 0, 0),
+	GATE(CLK_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8, 0, 0),
+	GATE(CLK_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9, 0, 0),
+	GATE(CLK_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10, 0, 0),
+	GATE(CLK_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11, 0, 0),
+	GATE(CLK_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12, 0, 0),
+	GATE(CLK_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20, 0, 0),
+	GATE(CLK_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21, 0, 0),
+	GATE(CLK_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23, 0, 0),
+	GATE(CLK_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24, 0, 0),
+	GATE(CLK_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25, 0, 0),
+	GATE(CLK_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26, 0, 0),
+	GATE(CLK_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27, 0, 0),
+	GATE(CLK_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28, 0, 0),
+	GATE(CLK_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30, 0, 0),
+	GATE(CLK_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31, 0, 0),
+	GATE(CLK_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0, 0, 0),
+	GATE(CLK_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4, 0, 0),
+	GATE(CLK_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12, 0, 0),
+	GATE(CLK_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13, 0, 0),
+};
+
 static const struct samsung_clock_alias exynos4_aliases[] __initconst = {
 	ALIAS(CLK_MOUT_CORE, NULL, "moutcore"),
 	ALIAS(CLK_ARM_CLK, NULL, "armclk"),
@@ -1438,6 +1431,100 @@ static void __init exynos4x12_core_down_clock(void)
 	{  0 },
 };
 
+static int exynos4x12_isp_clk_suspend(struct device *dev)
+{
+	samsung_clk_save(reg_base, exynos4x12_save_isp,
+				ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int exynos4x12_isp_clk_resume(struct device *dev)
+{
+	samsung_clk_restore(reg_base, exynos4x12_save_isp,
+				ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int __init exynos4x12_isp_clk_probe(struct platform_device *pdev)
+{
+	struct samsung_clk_provider *ctx = exynos4412_ctx;
+
+	if (!ctx)
+		return -ENODEV;
+
+	exynos4x12_save_isp = samsung_clk_alloc_reg_dump(exynos4x12_clk_isp_save,
+					ARRAY_SIZE(exynos4x12_clk_isp_save));
+	if (!exynos4x12_save_isp)
+		return -ENOMEM;
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	ctx->dev = &pdev->dev;
+
+	samsung_clk_register_div(ctx, exynos4x12_isp_div_clks,
+		ARRAY_SIZE(exynos4x12_isp_div_clks));
+	samsung_clk_register_gate(ctx, exynos4x12_isp_gate_clks,
+		ARRAY_SIZE(exynos4x12_isp_gate_clks));
+
+	return 0;
+}
+
+static const struct of_device_id exynos4x12_isp_clk_of_match[] = {
+	{ .compatible = "samsung,exynos4412-isp-clock", },
+	{ },
+};
+
+static const struct dev_pm_ops exynos4x12_isp_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos4x12_isp_clk_suspend,
+			   exynos4x12_isp_clk_resume, NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
+};
+
+static struct platform_driver exynos4x12_isp_clk_driver __refdata = {
+	.driver	= {
+		.name = "exynos-isp-clk",
+		.of_match_table = exynos4x12_isp_clk_of_match,
+		.suppress_bind_attrs = true,
+		.pm = &exynos4x12_isp_pm_ops,
+	},
+	.probe = exynos4x12_isp_clk_probe,
+};
+
+static int __init exynos4x12_isp_clk_init(void)
+{
+	if (!exynos4412_clk_node)
+		return 0;
+
+	of_platform_populate(exynos4412_clk_node, NULL, NULL, NULL);
+	return platform_driver_register(&exynos4x12_isp_clk_driver);
+}
+arch_initcall(exynos4x12_isp_clk_init);
+
+static void __init exynos4x12_isp_defer_clocks(struct samsung_clk_provider *ctx,
+					       struct device_node *parent)
+{
+	struct device_node *np = of_get_next_available_child(parent, NULL);
+	if (!np)
+		return;
+
+	if (of_device_is_compatible(np,
+		    exynos4x12_isp_clk_of_match[0].compatible)) {
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(exynos4x12_isp_div_clks); i++)
+			samsung_clk_add_lookup(ctx, ERR_PTR(-EPROBE_DEFER),
+					       exynos4x12_isp_div_clks[i].id);
+		for (i = 0; i < ARRAY_SIZE(exynos4x12_isp_gate_clks); i++)
+			samsung_clk_add_lookup(ctx, ERR_PTR(-EPROBE_DEFER),
+					       exynos4x12_isp_gate_clks[i].id);
+		exynos4412_ctx = ctx;
+		exynos4412_clk_node = parent;
+	}
+	of_node_put(np);
+}
+
 /* register exynos4 clocks */
 static void __init exynos4_clk_init(struct device_node *np,
 				    enum exynos4_soc soc)
@@ -1529,6 +1616,8 @@ static void __init exynos4_clk_init(struct device_node *np,
 		samsung_clk_register_fixed_factor(ctx,
 			exynos4x12_fixed_factor_clks,
 			ARRAY_SIZE(exynos4x12_fixed_factor_clks));
+		exynos4x12_isp_defer_clocks(ctx, np);
+
 		if (of_machine_is_compatible("samsung,exynos4412")) {
 			exynos_register_cpu_clock(ctx, CLK_ARM_CLK, "armclk",
 				mout_core_p4x12[0], mout_core_p4x12[1], 0x14200,
-- 
1.9.1

[PATCH v3 4/5] ARM: dts: exynos: add support for ISP power domain to exynos4x12 clocks device

[Marek Szyprowski]

Exynos4412 clock controller contains some additional clocks for FIMC-ISP
(Camera ISP) subsystem. Registers for those clocks are partially located
in the SOC area, which belongs to ISP power domain.

This patch implements integration of ISP clocks with ISP power domain.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 arch/arm/boot/dts/exynos4x12.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/exynos4x12.dtsi b/arch/arm/boot/dts/exynos4x12.dtsi
index 0074f566cd3b..5667fd33dc98 100644
--- a/arch/arm/boot/dts/exynos4x12.dtsi
+++ b/arch/arm/boot/dts/exynos4x12.dtsi
@@ -74,6 +74,11 @@
 		compatible = "samsung,exynos4412-clock";
 		reg = <0x10030000 0x20000>;
 		#clock-cells = <1>;
+
+		isp-clock-controller {
+			compatible = "samsung,exynos4412-isp-clock";
+			power-domains = <&pd_isp>;
+		};
 	};
 
 	mct@10050000 {
-- 
1.9.1

[PATCH v3 4/5] ARM: dts: exynos: add support for ISP power domain to exynos4x12 clocks device

[Marek Szyprowski]

Exynos4412 clock controller contains some additional clocks for FIMC-ISP
(Camera ISP) subsystem. Registers for those clocks are partially located
in the SOC area, which belongs to ISP power domain.

This patch implements integration of ISP clocks with ISP power domain.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 arch/arm/boot/dts/exynos4x12.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/exynos4x12.dtsi b/arch/arm/boot/dts/exynos4x12.dtsi
index 0074f566cd3b..5667fd33dc98 100644
--- a/arch/arm/boot/dts/exynos4x12.dtsi
+++ b/arch/arm/boot/dts/exynos4x12.dtsi
@@ -74,6 +74,11 @@
 		compatible = "samsung,exynos4412-clock";
 		reg = <0x10030000 0x20000>;
 		#clock-cells = <1>;
+
+		isp-clock-controller {
+			compatible = "samsung,exynos4412-isp-clock";
+			power-domains = <&pd_isp>;
+		};
 	};
 
 	mct at 10050000 {
-- 
1.9.1

[PATCH v3 5/5] clocks: exynos5433: add runtime pm support

[Marek Szyprowski]

Add runtime pm support for all clock controller units (CMU), which belongs
to power domains and require special handling during on/off operations.
Typically special values has to be written to MUX registers to change
internal clocks parents to OSC clock before turning power off. During such
operation all clocks, which enters CMU has to be enabled to let MUX to
stabilize. Also for each CMU there is one special parent clock, which has
to be enabled all the time when any access to CMU registers is done.

This patch solves most of the mysterious external abort and freeze issues
caused by a lack of proper parent CMU clock enabled or incorrect turn off
procedure.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/samsung/clk-exynos5433.c | 390 ++++++++++++++++++++++++++++-------
 drivers/clk/samsung/clk.h            |   6 +
 2 files changed, 319 insertions(+), 77 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5433.c b/drivers/clk/samsung/clk-exynos5433.c
index ea1608682d7f..40531652a5a6 100644
--- a/drivers/clk/samsung/clk-exynos5433.c
+++ b/drivers/clk/samsung/clk-exynos5433.c
@@ -9,9 +9,14 @@
  * Common Clock Framework support for Exynos5443 SoC.
  */
 
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
 
 #include <dt-bindings/clock/exynos5433.h>
 
@@ -2333,6 +2338,10 @@ static void __init exynos5433_cmu_fsys_init(struct device_node *np)
 	DIV_ENABLE_IP_G2D_SECURE_SMMU_G2D,
 };
 
+static const struct samsung_clk_reg_dump g2d_suspend_regs[] = {
+	{ MUX_SEL_G2D0, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aclk_g2d_266_user_p)		= { "oscclk", "aclk_g2d_266", };
 PNAME(mout_aclk_g2d_400_user_p)		= { "oscclk", "aclk_g2d_400", };
@@ -2418,16 +2427,11 @@ static void __init exynos5433_cmu_fsys_init(struct device_node *np)
 	.nr_clk_ids		= G2D_NR_CLK,
 	.clk_regs		= g2d_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(g2d_clk_regs),
+	.suspend_regs		= g2d_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(g2d_suspend_regs),
+	.clk_name		= "aclk_g2d_400",
 };
 
-static void __init exynos5433_cmu_g2d_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &g2d_cmu_info);
-}
-
-CLK_OF_DECLARE(exynos5433_cmu_g2d, "samsung,exynos5433-cmu-g2d",
-		exynos5433_cmu_g2d_init);
-
 /*
  * Register offset definitions for CMU_DISP
  */
@@ -2492,6 +2496,14 @@ static void __init exynos5433_cmu_g2d_init(struct device_node *np)
 	CLKOUT_CMU_DISP_DIV_STAT,
 };
 
+static const struct samsung_clk_reg_dump disp_suspend_regs[] = {
+	{ MUX_SEL_DISP0, 0 },
+	{ MUX_SEL_DISP1, 0 },
+	{ MUX_SEL_DISP2, 0 },
+	{ MUX_SEL_DISP3, 0 },
+	{ MUX_SEL_DISP4, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_disp_pll_p)			= { "oscclk", "fout_disp_pll", };
 PNAME(mout_sclk_dsim1_user_p)		= { "oscclk", "sclk_dsim1_disp", };
@@ -2837,16 +2849,11 @@ static void __init exynos5433_cmu_g2d_init(struct device_node *np)
 	.nr_clk_ids		= DISP_NR_CLK,
 	.clk_regs		= disp_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(disp_clk_regs),
+	.suspend_regs		= disp_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(disp_suspend_regs),
+	.clk_name		= "aclk_disp_333",
 };
 
-static void __init exynos5433_cmu_disp_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &disp_cmu_info);
-}
-
-CLK_OF_DECLARE(exynos5433_cmu_disp, "samsung,exynos5433-cmu-disp",
-		exynos5433_cmu_disp_init);
-
 /*
  * Register offset definitions for CMU_AUD
  */
@@ -2881,6 +2888,11 @@ static void __init exynos5433_cmu_disp_init(struct device_node *np)
 	ENABLE_IP_AUD1,
 };
 
+static const struct samsung_clk_reg_dump aud_suspend_regs[] = {
+	{ MUX_SEL_AUD0, 0 },
+	{ MUX_SEL_AUD1, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aud_pll_user_aud_p)	= { "oscclk", "fout_aud_pll", };
 PNAME(mout_sclk_aud_pcm_p)	= { "mout_aud_pll_user", "ioclk_audiocdclk0",};
@@ -3007,16 +3019,10 @@ static void __init exynos5433_cmu_disp_init(struct device_node *np)
 	.nr_clk_ids		= AUD_NR_CLK,
 	.clk_regs		= aud_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(aud_clk_regs),
+	.suspend_regs		= aud_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(aud_suspend_regs),
 };
 
-static void __init exynos5433_cmu_aud_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &aud_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_aud, "samsung,exynos5433-cmu-aud",
-		exynos5433_cmu_aud_init);
-
-
 /*
  * Register offset definitions for CMU_BUS{0|1|2}
  */
@@ -3218,6 +3224,10 @@ static void __init exynos5433_cmu_aud_init(struct device_node *np)
 	CLK_STOPCTRL,
 };
 
+static const struct samsung_clk_reg_dump g3d_suspend_regs[] = {
+	{ MUX_SEL_G3D, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aclk_g3d_400_p)	= { "mout_g3d_pll", "aclk_g3d_400", };
 PNAME(mout_g3d_pll_p)		= { "oscclk", "fout_g3d_pll", };
@@ -3291,15 +3301,11 @@ static void __init exynos5433_cmu_aud_init(struct device_node *np)
 	.nr_clk_ids		= G3D_NR_CLK,
 	.clk_regs		= g3d_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(g3d_clk_regs),
+	.suspend_regs		= g3d_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(g3d_suspend_regs),
+	.clk_name		= "aclk_g3d_400",
 };
 
-static void __init exynos5433_cmu_g3d_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &g3d_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_g3d, "samsung,exynos5433-cmu-g3d",
-		exynos5433_cmu_g3d_init);
-
 /*
  * Register offset definitions for CMU_GSCL
  */
@@ -3338,6 +3344,12 @@ static void __init exynos5433_cmu_g3d_init(struct device_node *np)
 	ENABLE_IP_GSCL_SECURE_SMMU_GSCL2,
 };
 
+static const struct samsung_clk_reg_dump gscl_suspend_regs[] = {
+	{ MUX_SEL_GSCL, 0 },
+	{ ENABLE_ACLK_GSCL, 0xfff },
+	{ ENABLE_PCLK_GSCL, 0xff },
+};
+
 /* list of all parent clock list */
 PNAME(aclk_gscl_111_user_p)	= { "oscclk", "aclk_gscl_111", };
 PNAME(aclk_gscl_333_user_p)	= { "oscclk", "aclk_gscl_333", };
@@ -3432,15 +3444,11 @@ static void __init exynos5433_cmu_g3d_init(struct device_node *np)
 	.nr_clk_ids		= GSCL_NR_CLK,
 	.clk_regs		= gscl_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(gscl_clk_regs),
+	.suspend_regs		= gscl_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(gscl_suspend_regs),
+	.clk_name		= "aclk_gscl_111",
 };
 
-static void __init exynos5433_cmu_gscl_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &gscl_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_gscl, "samsung,exynos5433-cmu-gscl",
-		exynos5433_cmu_gscl_init);
-
 /*
  * Register offset definitions for CMU_APOLLO
  */
@@ -3966,6 +3974,11 @@ static void __init exynos5433_cmu_atlas_init(struct device_node *np)
 	ENABLE_IP_MSCL_SECURE_SMMU_JPEG,
 };
 
+static const struct samsung_clk_reg_dump mscl_suspend_regs[] = {
+	{ MUX_SEL_MSCL0, 0 },
+	{ MUX_SEL_MSCL1, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_sclk_jpeg_user_p)		= { "oscclk", "sclk_jpeg_mscl", };
 PNAME(mout_aclk_mscl_400_user_p)	= { "oscclk", "aclk_mscl_400", };
@@ -4078,15 +4091,11 @@ static void __init exynos5433_cmu_atlas_init(struct device_node *np)
 	.nr_clk_ids		= MSCL_NR_CLK,
 	.clk_regs		= mscl_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(mscl_clk_regs),
+	.suspend_regs		= mscl_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(mscl_suspend_regs),
+	.clk_name		= "aclk_mscl_400",
 };
 
-static void __init exynos5433_cmu_mscl_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &mscl_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_mscl, "samsung,exynos5433-cmu-mscl",
-		exynos5433_cmu_mscl_init);
-
 /*
  * Register offset definitions for CMU_MFC
  */
@@ -4116,6 +4125,10 @@ static void __init exynos5433_cmu_mscl_init(struct device_node *np)
 	ENABLE_IP_MFC_SECURE_SMMU_MFC,
 };
 
+static const struct samsung_clk_reg_dump mfc_suspend_regs[] = {
+	{ MUX_SEL_MFC, 0 },
+};
+
 PNAME(mout_aclk_mfc_400_user_p)		= { "oscclk", "aclk_mfc_400", };
 
 static const struct samsung_mux_clock mfc_mux_clks[] __initconst = {
@@ -4186,15 +4199,11 @@ static void __init exynos5433_cmu_mscl_init(struct device_node *np)
 	.nr_clk_ids		= MFC_NR_CLK,
 	.clk_regs		= mfc_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(mfc_clk_regs),
+	.suspend_regs		= mfc_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(mfc_suspend_regs),
+	.clk_name		= "aclk_mfc_400",
 };
 
-static void __init exynos5433_cmu_mfc_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &mfc_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_mfc, "samsung,exynos5433-cmu-mfc",
-		exynos5433_cmu_mfc_init);
-
 /*
  * Register offset definitions for CMU_HEVC
  */
@@ -4224,6 +4233,10 @@ static void __init exynos5433_cmu_mfc_init(struct device_node *np)
 	ENABLE_IP_HEVC_SECURE_SMMU_HEVC,
 };
 
+static const struct samsung_clk_reg_dump hevc_suspend_regs[] = {
+	{ MUX_SEL_HEVC, 0 },
+};
+
 PNAME(mout_aclk_hevc_400_user_p)	= { "oscclk", "aclk_hevc_400", };
 
 static const struct samsung_mux_clock hevc_mux_clks[] __initconst = {
@@ -4296,15 +4309,11 @@ static void __init exynos5433_cmu_mfc_init(struct device_node *np)
 	.nr_clk_ids		= HEVC_NR_CLK,
 	.clk_regs		= hevc_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(hevc_clk_regs),
+	.suspend_regs		= hevc_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(hevc_suspend_regs),
+	.clk_name		= "aclk_hevc_400",
 };
 
-static void __init exynos5433_cmu_hevc_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &hevc_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_hevc, "samsung,exynos5433-cmu-hevc",
-		exynos5433_cmu_hevc_init);
-
 /*
  * Register offset definitions for CMU_ISP
  */
@@ -4338,6 +4347,10 @@ static void __init exynos5433_cmu_hevc_init(struct device_node *np)
 	ENABLE_IP_ISP3,
 };
 
+static const struct samsung_clk_reg_dump isp_suspend_regs[] = {
+	{ MUX_SEL_ISP, 0 },
+};
+
 PNAME(mout_aclk_isp_dis_400_user_p)	= { "oscclk", "aclk_isp_dis_400", };
 PNAME(mout_aclk_isp_400_user_p)		= { "oscclk", "aclk_isp_400", };
 
@@ -4549,15 +4562,11 @@ static void __init exynos5433_cmu_hevc_init(struct device_node *np)
 	.nr_clk_ids		= ISP_NR_CLK,
 	.clk_regs		= isp_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(isp_clk_regs),
+	.suspend_regs		= isp_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(isp_suspend_regs),
+	.clk_name		= "aclk_isp_400",
 };
 
-static void __init exynos5433_cmu_isp_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &isp_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_isp, "samsung,exynos5433-cmu-isp",
-		exynos5433_cmu_isp_init);
-
 /*
  * Register offset definitions for CMU_CAM0
  */
@@ -4621,6 +4630,15 @@ static void __init exynos5433_cmu_isp_init(struct device_node *np)
 	ENABLE_IP_CAM02,
 	ENABLE_IP_CAM03,
 };
+
+static const struct samsung_clk_reg_dump cam0_suspend_regs[] = {
+	{ MUX_SEL_CAM00, 0 },
+	{ MUX_SEL_CAM01, 0 },
+	{ MUX_SEL_CAM02, 0 },
+	{ MUX_SEL_CAM03, 0 },
+	{ MUX_SEL_CAM04, 0 },
+};
+
 PNAME(mout_aclk_cam0_333_user_p)	= { "oscclk", "aclk_cam0_333", };
 PNAME(mout_aclk_cam0_400_user_p)	= { "oscclk", "aclk_cam0_400", };
 PNAME(mout_aclk_cam0_552_user_p)	= { "oscclk", "aclk_cam0_552", };
@@ -5026,15 +5044,11 @@ static void __init exynos5433_cmu_isp_init(struct device_node *np)
 	.nr_clk_ids		= CAM0_NR_CLK,
 	.clk_regs		= cam0_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(cam0_clk_regs),
+	.suspend_regs		= cam0_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(cam0_suspend_regs),
+	.clk_name		= "aclk_cam0_400",
 };
 
-static void __init exynos5433_cmu_cam0_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &cam0_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_cam0, "samsung,exynos5433-cmu-cam0",
-		exynos5433_cmu_cam0_init);
-
 /*
  * Register offset definitions for CMU_CAM1
  */
@@ -5081,6 +5095,12 @@ static void __init exynos5433_cmu_cam0_init(struct device_node *np)
 	ENABLE_IP_CAM12,
 };
 
+static const struct samsung_clk_reg_dump cam1_suspend_regs[] = {
+	{ MUX_SEL_CAM10, 0 },
+	{ MUX_SEL_CAM11, 0 },
+	{ MUX_SEL_CAM12, 0 },
+};
+
 PNAME(mout_sclk_isp_uart_user_p)	= { "oscclk", "sclk_isp_uart_cam1", };
 PNAME(mout_sclk_isp_spi1_user_p)	= { "oscclk", "sclk_isp_spi1_cam1", };
 PNAME(mout_sclk_isp_spi0_user_p)	= { "oscclk", "sclk_isp_spi0_cam1", };
@@ -5399,11 +5419,227 @@ static void __init exynos5433_cmu_cam0_init(struct device_node *np)
 	.nr_clk_ids		= CAM1_NR_CLK,
 	.clk_regs		= cam1_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(cam1_clk_regs),
+	.suspend_regs		= cam1_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(cam1_suspend_regs),
+	.clk_name		= "aclk_cam1_400",
+};
+
+
+struct exynos5433_cmu_data {
+	struct samsung_clk_provider ctx;
+
+	struct samsung_clk_reg_dump *clk_save;
+	unsigned int nr_clk_save;
+	const struct samsung_clk_reg_dump *clk_suspend;
+	unsigned int nr_clk_suspend;
+
+	struct clk *clk;
+	struct clk **pclks;
+	int nr_pclks;
+};
+
+static int exynos5433_cmu_suspend(struct device *dev)
+{
+	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
+	int i;
+
+	samsung_clk_save(data->ctx.reg_base, data->clk_save,
+			 data->nr_clk_save);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_enable(data->pclks[i]);
+
+	samsung_clk_restore(data->ctx.reg_base, data->clk_suspend,
+			    data->nr_clk_suspend);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_disable(data->pclks[i]);
+
+	clk_disable(data->clk);
+
+	return 0;
+}
+
+static int exynos5433_cmu_resume(struct device *dev)
+{
+	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
+	int i;
+
+	clk_enable(data->clk);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_enable(data->pclks[i]);
+
+	samsung_clk_restore(data->ctx.reg_base, data->clk_save,
+			    data->nr_clk_save);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_disable(data->pclks[i]);
+
+	return 0;
+}
+
+static int __init exynos5433_cmu_probe(struct platform_device *pdev)
+{
+	const struct samsung_cmu_info *info;
+	struct exynos5433_cmu_data *data;
+	struct samsung_clk_provider *ctx;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	void __iomem *reg_base;
+	struct clk **clk_table;
+	int i;
+
+	info = of_device_get_match_data(dev);
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	ctx = &data->ctx;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	reg_base = devm_ioremap_resource(dev, res);
+	if (!reg_base) {
+		dev_err(dev, "failed to map registers\n");
+		return -ENOMEM;
+	}
+
+	clk_table = devm_kcalloc(dev, info->nr_clk_ids, sizeof(struct clk *),
+				 GFP_KERNEL);
+	if (!clk_table)
+		return -ENOMEM;
+
+	for (i = 0; i < info->nr_clk_ids; ++i)
+		clk_table[i] = ERR_PTR(-ENOENT);
+
+	ctx->clk_data.clks = clk_table;
+	ctx->clk_data.clk_num = info->nr_clk_ids;
+	ctx->reg_base = reg_base;
+	ctx->dev = dev;
+	spin_lock_init(&ctx->lock);
+
+	data->clk_save = samsung_clk_alloc_reg_dump(info->clk_regs,
+						    info->nr_clk_regs);
+	data->nr_clk_save = info->nr_clk_regs;
+	data->clk_suspend = info->suspend_regs;
+	data->nr_clk_suspend = info->nr_suspend_regs;
+	data->nr_pclks = of_count_phandle_with_args(dev->of_node, "clocks",
+						    "#clock-cells");
+	if (data->nr_pclks > 0) {
+		data->pclks = devm_kcalloc(dev, sizeof(struct clk *),
+					   data->nr_pclks, GFP_KERNEL);
+
+		for (i = 0; i < data->nr_pclks; i++) {
+			struct clk *clk = of_clk_get(dev->of_node, i);
+
+			if (IS_ERR(clk))
+				return PTR_ERR(clk);
+			data->pclks[i] = clk;
+		}
+	}
+
+	/*
+	 * Prepare all parent clocks here to avoid potential deadlock caused
+	 * by global clock "prepare lock" grabbed by runtime pm callbacks
+	 * from pm workers.
+	 */
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_prepare(data->pclks[i]);
+
+	if (info->clk_name)
+		data->clk = clk_get(dev, info->clk_name);
+	clk_prepare_enable(data->clk);
+
+	platform_set_drvdata(pdev, data);
+
+	/*
+	 * Enable runtime pm here, so clock core with use runtime pm for all
+	 * registered clocks.
+	 */
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	if (info->pll_clks)
+		samsung_clk_register_pll(ctx, info->pll_clks, info->nr_pll_clks,
+					 reg_base);
+	if (info->mux_clks)
+		samsung_clk_register_mux(ctx, info->mux_clks,
+					 info->nr_mux_clks);
+	if (info->div_clks)
+		samsung_clk_register_div(ctx, info->div_clks,
+					 info->nr_div_clks);
+	if (info->gate_clks)
+		samsung_clk_register_gate(ctx, info->gate_clks,
+					  info->nr_gate_clks);
+	if (info->fixed_clks)
+		samsung_clk_register_fixed_rate(ctx, info->fixed_clks,
+						info->nr_fixed_clks);
+	if (info->fixed_factor_clks)
+		samsung_clk_register_fixed_factor(ctx, info->fixed_factor_clks,
+						  info->nr_fixed_factor_clks);
+
+	samsung_clk_of_add_provider(dev->of_node, ctx);
+
+	return 0;
+}
+
+static const struct of_device_id exynos5433_cmu_of_match[] = {
+	{
+		.compatible = "samsung,exynos5433-cmu-aud",
+		.data = &aud_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-cam0",
+		.data = &cam0_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-cam1",
+		.data = &cam1_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-disp",
+		.data = &disp_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-g2d",
+		.data = &g2d_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-g3d",
+		.data = &g3d_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-gscl",
+		.data = &gscl_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-mfc",
+		.data = &mfc_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-hevc",
+		.data = &hevc_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-isp",
+		.data = &isp_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-mscl",
+		.data = &mscl_cmu_info,
+	}, {
+	},
+};
+
+static const struct dev_pm_ops exynos5433_cmu_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos5433_cmu_suspend, exynos5433_cmu_resume,
+			   NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
+};
+
+static struct platform_driver exynos5433_cmu_driver __refdata = {
+	.driver	= {
+		.name = "exynos5433-cmu",
+		.of_match_table = exynos5433_cmu_of_match,
+		.suppress_bind_attrs = true,
+		.pm = &exynos5433_cmu_pm_ops,
+	},
+	.probe = exynos5433_cmu_probe,
 };
 
-static void __init exynos5433_cmu_cam1_init(struct device_node *np)
+static int __init exynos5433_cmu_init(void)
 {
-	samsung_cmu_register_one(np, &cam1_cmu_info);
+	return platform_driver_register(&exynos5433_cmu_driver);
 }
-CLK_OF_DECLARE(exynos5433_cmu_cam1, "samsung,exynos5433-cmu-cam1",
-		exynos5433_cmu_cam1_init);
+core_initcall(exynos5433_cmu_init);
diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h
index 9263d8a27c6b..664020cb4794 100644
--- a/drivers/clk/samsung/clk.h
+++ b/drivers/clk/samsung/clk.h
@@ -354,6 +354,12 @@ struct samsung_cmu_info {
 	/* list and number of clocks registers */
 	const unsigned long *clk_regs;
 	unsigned int nr_clk_regs;
+
+	/* list and number of clocks registers to set before suspend */
+	const struct samsung_clk_reg_dump *suspend_regs;
+	unsigned int nr_suspend_regs;
+	/* name of the parent clock needed for CMU register access */
+	const char *clk_name;
 };
 
 extern struct samsung_clk_provider *__init samsung_clk_init(
-- 
1.9.1

[PATCH v3 5/5] clocks: exynos5433: add runtime pm support

[Marek Szyprowski]

Add runtime pm support for all clock controller units (CMU), which belongs
to power domains and require special handling during on/off operations.
Typically special values has to be written to MUX registers to change
internal clocks parents to OSC clock before turning power off. During such
operation all clocks, which enters CMU has to be enabled to let MUX to
stabilize. Also for each CMU there is one special parent clock, which has
to be enabled all the time when any access to CMU registers is done.

This patch solves most of the mysterious external abort and freeze issues
caused by a lack of proper parent CMU clock enabled or incorrect turn off
procedure.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/clk/samsung/clk-exynos5433.c | 390 ++++++++++++++++++++++++++++-------
 drivers/clk/samsung/clk.h            |   6 +
 2 files changed, 319 insertions(+), 77 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5433.c b/drivers/clk/samsung/clk-exynos5433.c
index ea1608682d7f..40531652a5a6 100644
--- a/drivers/clk/samsung/clk-exynos5433.c
+++ b/drivers/clk/samsung/clk-exynos5433.c
@@ -9,9 +9,14 @@
  * Common Clock Framework support for Exynos5443 SoC.
  */
 
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
 
 #include <dt-bindings/clock/exynos5433.h>
 
@@ -2333,6 +2338,10 @@ static void __init exynos5433_cmu_fsys_init(struct device_node *np)
 	DIV_ENABLE_IP_G2D_SECURE_SMMU_G2D,
 };
 
+static const struct samsung_clk_reg_dump g2d_suspend_regs[] = {
+	{ MUX_SEL_G2D0, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aclk_g2d_266_user_p)		= { "oscclk", "aclk_g2d_266", };
 PNAME(mout_aclk_g2d_400_user_p)		= { "oscclk", "aclk_g2d_400", };
@@ -2418,16 +2427,11 @@ static void __init exynos5433_cmu_fsys_init(struct device_node *np)
 	.nr_clk_ids		= G2D_NR_CLK,
 	.clk_regs		= g2d_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(g2d_clk_regs),
+	.suspend_regs		= g2d_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(g2d_suspend_regs),
+	.clk_name		= "aclk_g2d_400",
 };
 
-static void __init exynos5433_cmu_g2d_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &g2d_cmu_info);
-}
-
-CLK_OF_DECLARE(exynos5433_cmu_g2d, "samsung,exynos5433-cmu-g2d",
-		exynos5433_cmu_g2d_init);
-
 /*
  * Register offset definitions for CMU_DISP
  */
@@ -2492,6 +2496,14 @@ static void __init exynos5433_cmu_g2d_init(struct device_node *np)
 	CLKOUT_CMU_DISP_DIV_STAT,
 };
 
+static const struct samsung_clk_reg_dump disp_suspend_regs[] = {
+	{ MUX_SEL_DISP0, 0 },
+	{ MUX_SEL_DISP1, 0 },
+	{ MUX_SEL_DISP2, 0 },
+	{ MUX_SEL_DISP3, 0 },
+	{ MUX_SEL_DISP4, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_disp_pll_p)			= { "oscclk", "fout_disp_pll", };
 PNAME(mout_sclk_dsim1_user_p)		= { "oscclk", "sclk_dsim1_disp", };
@@ -2837,16 +2849,11 @@ static void __init exynos5433_cmu_g2d_init(struct device_node *np)
 	.nr_clk_ids		= DISP_NR_CLK,
 	.clk_regs		= disp_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(disp_clk_regs),
+	.suspend_regs		= disp_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(disp_suspend_regs),
+	.clk_name		= "aclk_disp_333",
 };
 
-static void __init exynos5433_cmu_disp_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &disp_cmu_info);
-}
-
-CLK_OF_DECLARE(exynos5433_cmu_disp, "samsung,exynos5433-cmu-disp",
-		exynos5433_cmu_disp_init);
-
 /*
  * Register offset definitions for CMU_AUD
  */
@@ -2881,6 +2888,11 @@ static void __init exynos5433_cmu_disp_init(struct device_node *np)
 	ENABLE_IP_AUD1,
 };
 
+static const struct samsung_clk_reg_dump aud_suspend_regs[] = {
+	{ MUX_SEL_AUD0, 0 },
+	{ MUX_SEL_AUD1, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aud_pll_user_aud_p)	= { "oscclk", "fout_aud_pll", };
 PNAME(mout_sclk_aud_pcm_p)	= { "mout_aud_pll_user", "ioclk_audiocdclk0",};
@@ -3007,16 +3019,10 @@ static void __init exynos5433_cmu_disp_init(struct device_node *np)
 	.nr_clk_ids		= AUD_NR_CLK,
 	.clk_regs		= aud_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(aud_clk_regs),
+	.suspend_regs		= aud_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(aud_suspend_regs),
 };
 
-static void __init exynos5433_cmu_aud_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &aud_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_aud, "samsung,exynos5433-cmu-aud",
-		exynos5433_cmu_aud_init);
-
-
 /*
  * Register offset definitions for CMU_BUS{0|1|2}
  */
@@ -3218,6 +3224,10 @@ static void __init exynos5433_cmu_aud_init(struct device_node *np)
 	CLK_STOPCTRL,
 };
 
+static const struct samsung_clk_reg_dump g3d_suspend_regs[] = {
+	{ MUX_SEL_G3D, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_aclk_g3d_400_p)	= { "mout_g3d_pll", "aclk_g3d_400", };
 PNAME(mout_g3d_pll_p)		= { "oscclk", "fout_g3d_pll", };
@@ -3291,15 +3301,11 @@ static void __init exynos5433_cmu_aud_init(struct device_node *np)
 	.nr_clk_ids		= G3D_NR_CLK,
 	.clk_regs		= g3d_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(g3d_clk_regs),
+	.suspend_regs		= g3d_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(g3d_suspend_regs),
+	.clk_name		= "aclk_g3d_400",
 };
 
-static void __init exynos5433_cmu_g3d_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &g3d_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_g3d, "samsung,exynos5433-cmu-g3d",
-		exynos5433_cmu_g3d_init);
-
 /*
  * Register offset definitions for CMU_GSCL
  */
@@ -3338,6 +3344,12 @@ static void __init exynos5433_cmu_g3d_init(struct device_node *np)
 	ENABLE_IP_GSCL_SECURE_SMMU_GSCL2,
 };
 
+static const struct samsung_clk_reg_dump gscl_suspend_regs[] = {
+	{ MUX_SEL_GSCL, 0 },
+	{ ENABLE_ACLK_GSCL, 0xfff },
+	{ ENABLE_PCLK_GSCL, 0xff },
+};
+
 /* list of all parent clock list */
 PNAME(aclk_gscl_111_user_p)	= { "oscclk", "aclk_gscl_111", };
 PNAME(aclk_gscl_333_user_p)	= { "oscclk", "aclk_gscl_333", };
@@ -3432,15 +3444,11 @@ static void __init exynos5433_cmu_g3d_init(struct device_node *np)
 	.nr_clk_ids		= GSCL_NR_CLK,
 	.clk_regs		= gscl_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(gscl_clk_regs),
+	.suspend_regs		= gscl_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(gscl_suspend_regs),
+	.clk_name		= "aclk_gscl_111",
 };
 
-static void __init exynos5433_cmu_gscl_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &gscl_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_gscl, "samsung,exynos5433-cmu-gscl",
-		exynos5433_cmu_gscl_init);
-
 /*
  * Register offset definitions for CMU_APOLLO
  */
@@ -3966,6 +3974,11 @@ static void __init exynos5433_cmu_atlas_init(struct device_node *np)
 	ENABLE_IP_MSCL_SECURE_SMMU_JPEG,
 };
 
+static const struct samsung_clk_reg_dump mscl_suspend_regs[] = {
+	{ MUX_SEL_MSCL0, 0 },
+	{ MUX_SEL_MSCL1, 0 },
+};
+
 /* list of all parent clock list */
 PNAME(mout_sclk_jpeg_user_p)		= { "oscclk", "sclk_jpeg_mscl", };
 PNAME(mout_aclk_mscl_400_user_p)	= { "oscclk", "aclk_mscl_400", };
@@ -4078,15 +4091,11 @@ static void __init exynos5433_cmu_atlas_init(struct device_node *np)
 	.nr_clk_ids		= MSCL_NR_CLK,
 	.clk_regs		= mscl_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(mscl_clk_regs),
+	.suspend_regs		= mscl_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(mscl_suspend_regs),
+	.clk_name		= "aclk_mscl_400",
 };
 
-static void __init exynos5433_cmu_mscl_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &mscl_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_mscl, "samsung,exynos5433-cmu-mscl",
-		exynos5433_cmu_mscl_init);
-
 /*
  * Register offset definitions for CMU_MFC
  */
@@ -4116,6 +4125,10 @@ static void __init exynos5433_cmu_mscl_init(struct device_node *np)
 	ENABLE_IP_MFC_SECURE_SMMU_MFC,
 };
 
+static const struct samsung_clk_reg_dump mfc_suspend_regs[] = {
+	{ MUX_SEL_MFC, 0 },
+};
+
 PNAME(mout_aclk_mfc_400_user_p)		= { "oscclk", "aclk_mfc_400", };
 
 static const struct samsung_mux_clock mfc_mux_clks[] __initconst = {
@@ -4186,15 +4199,11 @@ static void __init exynos5433_cmu_mscl_init(struct device_node *np)
 	.nr_clk_ids		= MFC_NR_CLK,
 	.clk_regs		= mfc_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(mfc_clk_regs),
+	.suspend_regs		= mfc_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(mfc_suspend_regs),
+	.clk_name		= "aclk_mfc_400",
 };
 
-static void __init exynos5433_cmu_mfc_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &mfc_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_mfc, "samsung,exynos5433-cmu-mfc",
-		exynos5433_cmu_mfc_init);
-
 /*
  * Register offset definitions for CMU_HEVC
  */
@@ -4224,6 +4233,10 @@ static void __init exynos5433_cmu_mfc_init(struct device_node *np)
 	ENABLE_IP_HEVC_SECURE_SMMU_HEVC,
 };
 
+static const struct samsung_clk_reg_dump hevc_suspend_regs[] = {
+	{ MUX_SEL_HEVC, 0 },
+};
+
 PNAME(mout_aclk_hevc_400_user_p)	= { "oscclk", "aclk_hevc_400", };
 
 static const struct samsung_mux_clock hevc_mux_clks[] __initconst = {
@@ -4296,15 +4309,11 @@ static void __init exynos5433_cmu_mfc_init(struct device_node *np)
 	.nr_clk_ids		= HEVC_NR_CLK,
 	.clk_regs		= hevc_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(hevc_clk_regs),
+	.suspend_regs		= hevc_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(hevc_suspend_regs),
+	.clk_name		= "aclk_hevc_400",
 };
 
-static void __init exynos5433_cmu_hevc_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &hevc_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_hevc, "samsung,exynos5433-cmu-hevc",
-		exynos5433_cmu_hevc_init);
-
 /*
  * Register offset definitions for CMU_ISP
  */
@@ -4338,6 +4347,10 @@ static void __init exynos5433_cmu_hevc_init(struct device_node *np)
 	ENABLE_IP_ISP3,
 };
 
+static const struct samsung_clk_reg_dump isp_suspend_regs[] = {
+	{ MUX_SEL_ISP, 0 },
+};
+
 PNAME(mout_aclk_isp_dis_400_user_p)	= { "oscclk", "aclk_isp_dis_400", };
 PNAME(mout_aclk_isp_400_user_p)		= { "oscclk", "aclk_isp_400", };
 
@@ -4549,15 +4562,11 @@ static void __init exynos5433_cmu_hevc_init(struct device_node *np)
 	.nr_clk_ids		= ISP_NR_CLK,
 	.clk_regs		= isp_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(isp_clk_regs),
+	.suspend_regs		= isp_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(isp_suspend_regs),
+	.clk_name		= "aclk_isp_400",
 };
 
-static void __init exynos5433_cmu_isp_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &isp_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_isp, "samsung,exynos5433-cmu-isp",
-		exynos5433_cmu_isp_init);
-
 /*
  * Register offset definitions for CMU_CAM0
  */
@@ -4621,6 +4630,15 @@ static void __init exynos5433_cmu_isp_init(struct device_node *np)
 	ENABLE_IP_CAM02,
 	ENABLE_IP_CAM03,
 };
+
+static const struct samsung_clk_reg_dump cam0_suspend_regs[] = {
+	{ MUX_SEL_CAM00, 0 },
+	{ MUX_SEL_CAM01, 0 },
+	{ MUX_SEL_CAM02, 0 },
+	{ MUX_SEL_CAM03, 0 },
+	{ MUX_SEL_CAM04, 0 },
+};
+
 PNAME(mout_aclk_cam0_333_user_p)	= { "oscclk", "aclk_cam0_333", };
 PNAME(mout_aclk_cam0_400_user_p)	= { "oscclk", "aclk_cam0_400", };
 PNAME(mout_aclk_cam0_552_user_p)	= { "oscclk", "aclk_cam0_552", };
@@ -5026,15 +5044,11 @@ static void __init exynos5433_cmu_isp_init(struct device_node *np)
 	.nr_clk_ids		= CAM0_NR_CLK,
 	.clk_regs		= cam0_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(cam0_clk_regs),
+	.suspend_regs		= cam0_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(cam0_suspend_regs),
+	.clk_name		= "aclk_cam0_400",
 };
 
-static void __init exynos5433_cmu_cam0_init(struct device_node *np)
-{
-	samsung_cmu_register_one(np, &cam0_cmu_info);
-}
-CLK_OF_DECLARE(exynos5433_cmu_cam0, "samsung,exynos5433-cmu-cam0",
-		exynos5433_cmu_cam0_init);
-
 /*
  * Register offset definitions for CMU_CAM1
  */
@@ -5081,6 +5095,12 @@ static void __init exynos5433_cmu_cam0_init(struct device_node *np)
 	ENABLE_IP_CAM12,
 };
 
+static const struct samsung_clk_reg_dump cam1_suspend_regs[] = {
+	{ MUX_SEL_CAM10, 0 },
+	{ MUX_SEL_CAM11, 0 },
+	{ MUX_SEL_CAM12, 0 },
+};
+
 PNAME(mout_sclk_isp_uart_user_p)	= { "oscclk", "sclk_isp_uart_cam1", };
 PNAME(mout_sclk_isp_spi1_user_p)	= { "oscclk", "sclk_isp_spi1_cam1", };
 PNAME(mout_sclk_isp_spi0_user_p)	= { "oscclk", "sclk_isp_spi0_cam1", };
@@ -5399,11 +5419,227 @@ static void __init exynos5433_cmu_cam0_init(struct device_node *np)
 	.nr_clk_ids		= CAM1_NR_CLK,
 	.clk_regs		= cam1_clk_regs,
 	.nr_clk_regs		= ARRAY_SIZE(cam1_clk_regs),
+	.suspend_regs		= cam1_suspend_regs,
+	.nr_suspend_regs	= ARRAY_SIZE(cam1_suspend_regs),
+	.clk_name		= "aclk_cam1_400",
+};
+
+
+struct exynos5433_cmu_data {
+	struct samsung_clk_provider ctx;
+
+	struct samsung_clk_reg_dump *clk_save;
+	unsigned int nr_clk_save;
+	const struct samsung_clk_reg_dump *clk_suspend;
+	unsigned int nr_clk_suspend;
+
+	struct clk *clk;
+	struct clk **pclks;
+	int nr_pclks;
+};
+
+static int exynos5433_cmu_suspend(struct device *dev)
+{
+	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
+	int i;
+
+	samsung_clk_save(data->ctx.reg_base, data->clk_save,
+			 data->nr_clk_save);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_enable(data->pclks[i]);
+
+	samsung_clk_restore(data->ctx.reg_base, data->clk_suspend,
+			    data->nr_clk_suspend);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_disable(data->pclks[i]);
+
+	clk_disable(data->clk);
+
+	return 0;
+}
+
+static int exynos5433_cmu_resume(struct device *dev)
+{
+	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
+	int i;
+
+	clk_enable(data->clk);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_enable(data->pclks[i]);
+
+	samsung_clk_restore(data->ctx.reg_base, data->clk_save,
+			    data->nr_clk_save);
+
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_disable(data->pclks[i]);
+
+	return 0;
+}
+
+static int __init exynos5433_cmu_probe(struct platform_device *pdev)
+{
+	const struct samsung_cmu_info *info;
+	struct exynos5433_cmu_data *data;
+	struct samsung_clk_provider *ctx;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	void __iomem *reg_base;
+	struct clk **clk_table;
+	int i;
+
+	info = of_device_get_match_data(dev);
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	ctx = &data->ctx;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	reg_base = devm_ioremap_resource(dev, res);
+	if (!reg_base) {
+		dev_err(dev, "failed to map registers\n");
+		return -ENOMEM;
+	}
+
+	clk_table = devm_kcalloc(dev, info->nr_clk_ids, sizeof(struct clk *),
+				 GFP_KERNEL);
+	if (!clk_table)
+		return -ENOMEM;
+
+	for (i = 0; i < info->nr_clk_ids; ++i)
+		clk_table[i] = ERR_PTR(-ENOENT);
+
+	ctx->clk_data.clks = clk_table;
+	ctx->clk_data.clk_num = info->nr_clk_ids;
+	ctx->reg_base = reg_base;
+	ctx->dev = dev;
+	spin_lock_init(&ctx->lock);
+
+	data->clk_save = samsung_clk_alloc_reg_dump(info->clk_regs,
+						    info->nr_clk_regs);
+	data->nr_clk_save = info->nr_clk_regs;
+	data->clk_suspend = info->suspend_regs;
+	data->nr_clk_suspend = info->nr_suspend_regs;
+	data->nr_pclks = of_count_phandle_with_args(dev->of_node, "clocks",
+						    "#clock-cells");
+	if (data->nr_pclks > 0) {
+		data->pclks = devm_kcalloc(dev, sizeof(struct clk *),
+					   data->nr_pclks, GFP_KERNEL);
+
+		for (i = 0; i < data->nr_pclks; i++) {
+			struct clk *clk = of_clk_get(dev->of_node, i);
+
+			if (IS_ERR(clk))
+				return PTR_ERR(clk);
+			data->pclks[i] = clk;
+		}
+	}
+
+	/*
+	 * Prepare all parent clocks here to avoid potential deadlock caused
+	 * by global clock "prepare lock" grabbed by runtime pm callbacks
+	 * from pm workers.
+	 */
+	for (i = 0; i < data->nr_pclks; i++)
+		clk_prepare(data->pclks[i]);
+
+	if (info->clk_name)
+		data->clk = clk_get(dev, info->clk_name);
+	clk_prepare_enable(data->clk);
+
+	platform_set_drvdata(pdev, data);
+
+	/*
+	 * Enable runtime pm here, so clock core with use runtime pm for all
+	 * registered clocks.
+	 */
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	if (info->pll_clks)
+		samsung_clk_register_pll(ctx, info->pll_clks, info->nr_pll_clks,
+					 reg_base);
+	if (info->mux_clks)
+		samsung_clk_register_mux(ctx, info->mux_clks,
+					 info->nr_mux_clks);
+	if (info->div_clks)
+		samsung_clk_register_div(ctx, info->div_clks,
+					 info->nr_div_clks);
+	if (info->gate_clks)
+		samsung_clk_register_gate(ctx, info->gate_clks,
+					  info->nr_gate_clks);
+	if (info->fixed_clks)
+		samsung_clk_register_fixed_rate(ctx, info->fixed_clks,
+						info->nr_fixed_clks);
+	if (info->fixed_factor_clks)
+		samsung_clk_register_fixed_factor(ctx, info->fixed_factor_clks,
+						  info->nr_fixed_factor_clks);
+
+	samsung_clk_of_add_provider(dev->of_node, ctx);
+
+	return 0;
+}
+
+static const struct of_device_id exynos5433_cmu_of_match[] = {
+	{
+		.compatible = "samsung,exynos5433-cmu-aud",
+		.data = &aud_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-cam0",
+		.data = &cam0_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-cam1",
+		.data = &cam1_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-disp",
+		.data = &disp_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-g2d",
+		.data = &g2d_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-g3d",
+		.data = &g3d_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-gscl",
+		.data = &gscl_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-mfc",
+		.data = &mfc_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-hevc",
+		.data = &hevc_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-isp",
+		.data = &isp_cmu_info,
+	}, {
+		.compatible = "samsung,exynos5433-cmu-mscl",
+		.data = &mscl_cmu_info,
+	}, {
+	},
+};
+
+static const struct dev_pm_ops exynos5433_cmu_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos5433_cmu_suspend, exynos5433_cmu_resume,
+			   NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
+};
+
+static struct platform_driver exynos5433_cmu_driver __refdata = {
+	.driver	= {
+		.name = "exynos5433-cmu",
+		.of_match_table = exynos5433_cmu_of_match,
+		.suppress_bind_attrs = true,
+		.pm = &exynos5433_cmu_pm_ops,
+	},
+	.probe = exynos5433_cmu_probe,
 };
 
-static void __init exynos5433_cmu_cam1_init(struct device_node *np)
+static int __init exynos5433_cmu_init(void)
 {
-	samsung_cmu_register_one(np, &cam1_cmu_info);
+	return platform_driver_register(&exynos5433_cmu_driver);
 }
-CLK_OF_DECLARE(exynos5433_cmu_cam1, "samsung,exynos5433-cmu-cam1",
-		exynos5433_cmu_cam1_init);
+core_initcall(exynos5433_cmu_init);
diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h
index 9263d8a27c6b..664020cb4794 100644
--- a/drivers/clk/samsung/clk.h
+++ b/drivers/clk/samsung/clk.h
@@ -354,6 +354,12 @@ struct samsung_cmu_info {
 	/* list and number of clocks registers */
 	const unsigned long *clk_regs;
 	unsigned int nr_clk_regs;
+
+	/* list and number of clocks registers to set before suspend */
+	const struct samsung_clk_reg_dump *suspend_regs;
+	unsigned int nr_suspend_regs;
+	/* name of the parent clock needed for CMU register access */
+	const char *clk_name;
 };
 
 extern struct samsung_clk_provider *__init samsung_clk_init(
-- 
1.9.1

Re: [PATCH v3 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[Marek Szyprowski]

Dear All,


On 2016-10-24 14:12, Marek Szyprowski wrote:
> This patchset adds runtime PM support to common clock framework. This is an
> attempt to implement support for clock controllers, which belongs to a power
> domain. This approach works surprisingly well on Exynos 4412 and 5433 SoCs,
> what allowed us to solve various freeze/crash issues related to power
> management.
>
> The main idea behind this patchset is to keep clock's controller power domain
> enabled every time when at least one of its clock is enabled or access to its
> registers is being made. Clock controller driver (clock provider) can
> supply a struct device pointer, which is the used by clock core for tracking and
> managing clock's controller runtime pm state. Each clk_prepare() operation will
> first call pm_runtime_get_sync() on the supplied device, while clk_unprepare()
> will do pm_runtime_put() at the end.
>
> This runtime PM feature has been tested with Exynos4412 and Exynos5433 clocks
> drivers. Both have some clocks, which belongs to respective power domains and
> need special handling during power on/off procedures. Till now it wasn't handled
> at all, what caused various problems.
>
> Patches for exynos 4412 and 5433 clocks drivers change the way the clock
> provider is initialized. Instead of CLK_OF_DECLARE based initialization, a
> complete platform device driver infrastructure is being used. This is needed to
> let driver to use runtime pm feature and integrate with generic power domains.
> The side-effect of this change is a delay in clock provider registeration
> during system boot, so early initialized drivers might get EPROBEDEFER error
> when requesting their clocks. This is an issue for IOMMU drivers, so
> this patchset will be fully functional once the deferred probe for IOMMU
> will be merged.
>
> The side-effect of this patchset is the one can finally read
> /sys/kernel/debug/clk/clk_summary on all Exynos4412 boards without any freeze.
>
> If one wants to test this patchset (on Exynos4412 Trats2 device with FIMC-IS
> driver), I've provided a branch with all needed patches (fixes for Exynos,
> FIMC-IS driver and IOMMU deferred probe):
> https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-clocks-pm-v3
>
> Patches are based on vanilla v4.9-rc1 kernel.

If one want to test this patchset together with my recently posted 
Exynos IOMMU
runtime PM patches (V5: 
http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1253432.html),
I prepared a single branch with both patchsets and all their prerequisites:

https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-iommu-pm-v5-clocks-pm-v3


Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland

[PATCH v3 0/5] Add runtime PM support for clocks (on Exynos SoC example)

[Marek Szyprowski]

Dear All,


On 2016-10-24 14:12, Marek Szyprowski wrote:
> This patchset adds runtime PM support to common clock framework. This is an
> attempt to implement support for clock controllers, which belongs to a power
> domain. This approach works surprisingly well on Exynos 4412 and 5433 SoCs,
> what allowed us to solve various freeze/crash issues related to power
> management.
>
> The main idea behind this patchset is to keep clock's controller power domain
> enabled every time when at least one of its clock is enabled or access to its
> registers is being made. Clock controller driver (clock provider) can
> supply a struct device pointer, which is the used by clock core for tracking and
> managing clock's controller runtime pm state. Each clk_prepare() operation will
> first call pm_runtime_get_sync() on the supplied device, while clk_unprepare()
> will do pm_runtime_put() at the end.
>
> This runtime PM feature has been tested with Exynos4412 and Exynos5433 clocks
> drivers. Both have some clocks, which belongs to respective power domains and
> need special handling during power on/off procedures. Till now it wasn't handled
> at all, what caused various problems.
>
> Patches for exynos 4412 and 5433 clocks drivers change the way the clock
> provider is initialized. Instead of CLK_OF_DECLARE based initialization, a
> complete platform device driver infrastructure is being used. This is needed to
> let driver to use runtime pm feature and integrate with generic power domains.
> The side-effect of this change is a delay in clock provider registeration
> during system boot, so early initialized drivers might get EPROBEDEFER error
> when requesting their clocks. This is an issue for IOMMU drivers, so
> this patchset will be fully functional once the deferred probe for IOMMU
> will be merged.
>
> The side-effect of this patchset is the one can finally read
> /sys/kernel/debug/clk/clk_summary on all Exynos4412 boards without any freeze.
>
> If one wants to test this patchset (on Exynos4412 Trats2 device with FIMC-IS
> driver), I've provided a branch with all needed patches (fixes for Exynos,
> FIMC-IS driver and IOMMU deferred probe):
> https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-clocks-pm-v3
>
> Patches are based on vanilla v4.9-rc1 kernel.

If one want to test this patchset together with my recently posted 
Exynos IOMMU
runtime PM patches (V5: 
http://www.mail-archive.com/linux-kernel at vger.kernel.org/msg1253432.html),
I prepared a single branch with both patchsets and all their prerequisites:

https://git.linaro.org/people/marek.szyprowski/linux-srpol.git v4.9-iommu-pm-v5-clocks-pm-v3


Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland