diff mbox

[v5,6/7] iommu/exynos: Add runtime pm support

Message ID 1476948173-21093-7-git-send-email-m.szyprowski@samsung.com
State Accepted
Commit 9b265536c271163ec4acc140ca0a40a732971cbf
Headers show

Commit Message

Marek Szyprowski Oct. 20, 2016, 7:22 a.m. UTC 
This patch adds runtime pm implementation, which is based on previous
suspend/resume code. SYSMMU controller is now being enabled/disabled mainly
from the runtime pm callbacks. System sleep callbacks relies on generic
pm_runtime_force_suspend/pm_runtime_force_resume helpers. To ensure
internal state consistency, additional lock for runtime pm transitions
was introduced.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

---
 drivers/iommu/exynos-iommu.c | 45 +++++++++++++++++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 9 deletions(-)

-- 
1.9.1

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Comments

Sricharan Ramabadhran Oct. 24, 2016, 12:15 p.m. UTC | #1 
Hi Marek,

>Hi Sricharan

>

>

>On 2016-10-22 07:50, Sricharan wrote:

>>

>>> This patch adds runtime pm implementation, which is based on previous

>>> suspend/resume code. SYSMMU controller is now being enabled/disabled mainly

>> > from the runtime pm callbacks. System sleep callbacks relies on generic

>>> pm_runtime_force_suspend/pm_runtime_force_resume helpers. To ensure

>>> internal state consistency, additional lock for runtime pm transitions

>>> was introduced.

>>>

>>> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

>>> ---

>>> drivers/iommu/exynos-iommu.c | 45 +++++++++++++++++++++++++++++++++++---------

>>> 1 file changed, 36 insertions(+), 9 deletions(-)

>>>

>>> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c

>>> index a959443e6f33..5e6d7bbf9b70 100644

>>> --- a/drivers/iommu/exynos-iommu.c

>>> +++ b/drivers/iommu/exynos-iommu.c

>>> @@ -206,6 +206,7 @@ struct sysmmu_fault_info {

>>> struct exynos_iommu_owner {

>>> 	struct list_head controllers;	/* list of sysmmu_drvdata.owner_node */

>>> 	struct iommu_domain *domain;	/* domain this device is attached */

>>> +	struct mutex rpm_lock;		/* for runtime pm of all sysmmus */

>>> };

>>>

>>> /*

>>> @@ -594,40 +595,46 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)

>>> 	return 0;

>>> }

>>>

>>> -#ifdef CONFIG_PM_SLEEP

>>> -static int exynos_sysmmu_suspend(struct device *dev)

>>> +static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)

>>> {

>>> 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);

>>> 	struct device *master = data->master;

>>>

>>> 	if (master) {

>>> -		pm_runtime_put(dev);

>>> +		struct exynos_iommu_owner *owner = master->archdata.iommu;

>>> +

>>> +		mutex_lock(&owner->rpm_lock);

>> More of a device link question,

>> To understand, i see that with device link + runtime, the supplier

>> callbacks are not called for irqsafe clients, even if supplier is irqsafe.

>> Why so ?

>

>Frankly I didn't care about irqsafe runtime pm, because there is no such

>need

>for Exynos platform and its drivers. Exynos power domain driver also doesn't

>support irqsafe mode.

  ok, i asked this because, i was doing the same thing for arm-smmu driver
   and thought that when we depend on device-link for doing the runtime pm,
   then it might not work for irqsafe master. Probably i can ask this on device link
    series post.

Regards,
 Sricharan

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diff mbox

Patch

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index a959443e6f33..5e6d7bbf9b70 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -206,6 +206,7 @@  struct sysmmu_fault_info {
 struct exynos_iommu_owner {
 	struct list_head controllers;	/* list of sysmmu_drvdata.owner_node */
 	struct iommu_domain *domain;	/* domain this device is attached */
+	struct mutex rpm_lock;		/* for runtime pm of all sysmmus */
 };
 
 /*
@@ -594,40 +595,46 @@  static int __init exynos_sysmmu_probe(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
-static int exynos_sysmmu_suspend(struct device *dev)
+static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
 {
 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 	struct device *master = data->master;
 
 	if (master) {
-		pm_runtime_put(dev);
+		struct exynos_iommu_owner *owner = master->archdata.iommu;
+
+		mutex_lock(&owner->rpm_lock);
 		if (data->domain) {
 			dev_dbg(data->sysmmu, "saving state\n");
 			__sysmmu_disable(data);
 		}
+		mutex_unlock(&owner->rpm_lock);
 	}
 	return 0;
 }
 
-static int exynos_sysmmu_resume(struct device *dev)
+static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
 {
 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);
 	struct device *master = data->master;
 
 	if (master) {
-		pm_runtime_get_sync(dev);
+		struct exynos_iommu_owner *owner = master->archdata.iommu;
+
+		mutex_lock(&owner->rpm_lock);
 		if (data->domain) {
 			dev_dbg(data->sysmmu, "restoring state\n");
 			__sysmmu_enable(data);
 		}
+		mutex_unlock(&owner->rpm_lock);
 	}
 	return 0;
 }
-#endif
 
 static const struct dev_pm_ops sysmmu_pm_ops = {
-	SET_LATE_SYSTEM_SLEEP_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume)
+	SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
 };
 
 static const struct of_device_id sysmmu_of_match[] __initconst = {
@@ -775,7 +782,15 @@  static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
 		return;
 
 	list_for_each_entry(data, &owner->controllers, owner_node) {
-		__sysmmu_disable(data);
+		pm_runtime_put_sync(data->sysmmu);
+	}
+
+	mutex_lock(&owner->rpm_lock);
+
+	list_for_each_entry(data, &owner->controllers, owner_node) {
+		pm_runtime_get_noresume(data->sysmmu);
+		if (pm_runtime_active(data->sysmmu))
+			__sysmmu_disable(data);
 		pm_runtime_put(data->sysmmu);
 	}
 
@@ -790,6 +805,7 @@  static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
 	owner->domain = NULL;
 	spin_unlock_irqrestore(&domain->lock, flags);
 
+	mutex_unlock(&owner->rpm_lock);
 
 	dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
 		&pagetable);
@@ -810,6 +826,8 @@  static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
 	if (owner->domain)
 		exynos_iommu_detach_device(owner->domain, dev);
 
+	mutex_lock(&owner->rpm_lock);
+
 	spin_lock_irqsave(&domain->lock, flags);
 	list_for_each_entry(data, &owner->controllers, owner_node) {
 		spin_lock(&data->lock);
@@ -822,8 +840,16 @@  static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
 	spin_unlock_irqrestore(&domain->lock, flags);
 
 	list_for_each_entry(data, &owner->controllers, owner_node) {
+		pm_runtime_get_noresume(data->sysmmu);
+		if (pm_runtime_active(data->sysmmu))
+			__sysmmu_enable(data);
+		pm_runtime_put(data->sysmmu);
+	}
+
+	mutex_unlock(&owner->rpm_lock);
+
+	list_for_each_entry(data, &owner->controllers, owner_node) {
 		pm_runtime_get_sync(data->sysmmu);
-		__sysmmu_enable(data);
 	}
 
 	dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
@@ -1200,6 +1226,7 @@  static int exynos_iommu_of_xlate(struct device *dev,
 			return -ENOMEM;
 
 		INIT_LIST_HEAD(&owner->controllers);
+		mutex_init(&owner->rpm_lock);
 		dev->archdata.iommu = owner;
 	}