diff mbox series

[v3,6/8] drm/panfrost: Convert MMU IRQ handler to threaded handler

Message ID 20190802195150.23207-7-robh@kernel.org
State Superseded
Headers show
Series drm/panfrost: Add heap and no execute buffer allocation | expand

Commit Message

Rob Herring (Arm) Aug. 2, 2019, 7:51 p.m. UTC
In preparation to handle mapping of page faults, we need the MMU handler
to be threaded as code paths take a mutex.

As the IRQ may be shared, we can't use the default handler and must
disable the MMU interrupts locally.

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
---
 drivers/gpu/drm/panfrost/panfrost_mmu.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

Comments

Alyssa Rosenzweig Aug. 2, 2019, 10:28 p.m. UTC | #1
A-b, I think.

On Fri, Aug 02, 2019 at 01:51:48PM -0600, Rob Herring wrote:
> In preparation to handle mapping of page faults, we need the MMU handler

> to be threaded as code paths take a mutex.

> 

> As the IRQ may be shared, we can't use the default handler and must

> disable the MMU interrupts locally.

> 

> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>

> Cc: Boris Brezillon <boris.brezillon@collabora.com>

> Cc: Robin Murphy <robin.murphy@arm.com>

> Cc: Steven Price <steven.price@arm.com>

> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>

> Signed-off-by: Rob Herring <robh@kernel.org>

> ---

>  drivers/gpu/drm/panfrost/panfrost_mmu.c | 20 +++++++++++++++-----

>  1 file changed, 15 insertions(+), 5 deletions(-)

> 

> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c

> index eba6ce785ef0..7d44328b280f 100644

> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c

> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c

> @@ -300,12 +300,20 @@ static const char *access_type_name(struct panfrost_device *pfdev,

>  static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)

>  {

>  	struct panfrost_device *pfdev = data;

> -	u32 status = mmu_read(pfdev, MMU_INT_STAT);

> -	int i;

>  

> -	if (!status)

> +	if (!mmu_read(pfdev, MMU_INT_STAT))

>  		return IRQ_NONE;

>  

> +	mmu_write(pfdev, MMU_INT_MASK, 0);

> +	return IRQ_WAKE_THREAD;

> +}

> +

> +static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)

> +{

> +	struct panfrost_device *pfdev = data;

> +	u32 status = mmu_read(pfdev, MMU_INT_RAWSTAT);

> +	int i;

> +

>  	dev_err(pfdev->dev, "mmu irq status=%x\n", status);

>  

>  	for (i = 0; status; i++) {

> @@ -350,6 +358,7 @@ static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)

>  		status &= ~mask;

>  	}

>  

> +	mmu_write(pfdev, MMU_INT_MASK, ~0);

>  	return IRQ_HANDLED;

>  };

>  

> @@ -368,8 +377,9 @@ int panfrost_mmu_init(struct panfrost_device *pfdev)

>  	if (irq <= 0)

>  		return -ENODEV;

>  

> -	err = devm_request_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,

> -			       IRQF_SHARED, "mmu", pfdev);

> +	err = devm_request_threaded_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,

> +					panfrost_mmu_irq_handler_thread,

> +					IRQF_SHARED, "mmu", pfdev);

>  

>  	if (err) {

>  		dev_err(pfdev->dev, "failed to request mmu irq");

> -- 

> 2.20.1

>
Steven Price Aug. 8, 2019, 12:57 p.m. UTC | #2
On 02/08/2019 20:51, Rob Herring wrote:
> In preparation to handle mapping of page faults, we need the MMU handler
> to be threaded as code paths take a mutex.
> 
> As the IRQ may be shared, we can't use the default handler and must
> disable the MMU interrupts locally.
> 
> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Cc: Boris Brezillon <boris.brezillon@collabora.com>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: Steven Price <steven.price@arm.com>
> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>

Reviewed-by: Steven Price <steven.price@arm.com>

> ---
>  drivers/gpu/drm/panfrost/panfrost_mmu.c | 20 +++++++++++++++-----
>  1 file changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> index eba6ce785ef0..7d44328b280f 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -300,12 +300,20 @@ static const char *access_type_name(struct panfrost_device *pfdev,
>  static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
>  {
>  	struct panfrost_device *pfdev = data;
> -	u32 status = mmu_read(pfdev, MMU_INT_STAT);
> -	int i;
>  
> -	if (!status)
> +	if (!mmu_read(pfdev, MMU_INT_STAT))
>  		return IRQ_NONE;
>  
> +	mmu_write(pfdev, MMU_INT_MASK, 0);
> +	return IRQ_WAKE_THREAD;
> +}
> +
> +static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
> +{
> +	struct panfrost_device *pfdev = data;
> +	u32 status = mmu_read(pfdev, MMU_INT_RAWSTAT);
> +	int i;
> +
>  	dev_err(pfdev->dev, "mmu irq status=%x\n", status);
>  
>  	for (i = 0; status; i++) {
> @@ -350,6 +358,7 @@ static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
>  		status &= ~mask;
>  	}
>  
> +	mmu_write(pfdev, MMU_INT_MASK, ~0);
>  	return IRQ_HANDLED;
>  };
>  
> @@ -368,8 +377,9 @@ int panfrost_mmu_init(struct panfrost_device *pfdev)
>  	if (irq <= 0)
>  		return -ENODEV;
>  
> -	err = devm_request_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
> -			       IRQF_SHARED, "mmu", pfdev);
> +	err = devm_request_threaded_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
> +					panfrost_mmu_irq_handler_thread,
> +					IRQF_SHARED, "mmu", pfdev);
>  
>  	if (err) {
>  		dev_err(pfdev->dev, "failed to request mmu irq");
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
index eba6ce785ef0..7d44328b280f 100644
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -300,12 +300,20 @@  static const char *access_type_name(struct panfrost_device *pfdev,
 static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
 {
 	struct panfrost_device *pfdev = data;
-	u32 status = mmu_read(pfdev, MMU_INT_STAT);
-	int i;
 
-	if (!status)
+	if (!mmu_read(pfdev, MMU_INT_STAT))
 		return IRQ_NONE;
 
+	mmu_write(pfdev, MMU_INT_MASK, 0);
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
+{
+	struct panfrost_device *pfdev = data;
+	u32 status = mmu_read(pfdev, MMU_INT_RAWSTAT);
+	int i;
+
 	dev_err(pfdev->dev, "mmu irq status=%x\n", status);
 
 	for (i = 0; status; i++) {
@@ -350,6 +358,7 @@  static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
 		status &= ~mask;
 	}
 
+	mmu_write(pfdev, MMU_INT_MASK, ~0);
 	return IRQ_HANDLED;
 };
 
@@ -368,8 +377,9 @@  int panfrost_mmu_init(struct panfrost_device *pfdev)
 	if (irq <= 0)
 		return -ENODEV;
 
-	err = devm_request_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
-			       IRQF_SHARED, "mmu", pfdev);
+	err = devm_request_threaded_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
+					panfrost_mmu_irq_handler_thread,
+					IRQF_SHARED, "mmu", pfdev);
 
 	if (err) {
 		dev_err(pfdev->dev, "failed to request mmu irq");