diff mbox series

[v2] drm/panfrost: Don't try to map on error faults

Message ID 20200212202236.13095-1-robh@kernel.org (mailing list archive)
State New, archived
Headers show
Series [v2] drm/panfrost: Don't try to map on error faults | expand

Commit Message

Rob Herring Feb. 12, 2020, 8:22 p.m. UTC 
From: Tomeu Vizoso <tomeu.vizoso@collabora.com>

If the exception type isn't a translation fault, don't try to map and
instead go straight to a terminal fault.

Otherwise, we can get flooded by kernel warnings and further faults.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
---
I rewrote this some simplifying the code and somewhat following Steven's 
suggested. Still not using defines though. No defines here was good 
enough before IMO.

Only compile tested.

 drivers/gpu/drm/panfrost/panfrost_mmu.c | 44 +++++++++++--------------
 1 file changed, 19 insertions(+), 25 deletions(-)

Comments

Steven Price Feb. 13, 2020, 11:13 a.m. UTC | #1 
On 12/02/2020 20:22, Rob Herring wrote:
> From: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> 
> If the exception type isn't a translation fault, don't try to map and
> instead go straight to a terminal fault.
> 
> Otherwise, we can get flooded by kernel warnings and further faults.
> 
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> I rewrote this some simplifying the code and somewhat following Steven's 
> suggested. Still not using defines though. No defines here was good 
> enough before IMO.

Heresy! It's a good thing you're not writing kbase code - there you
(seemingly) need to pick a #define which is as long as possible, but
then still wrap the code to avoid the 80 character limit... For
example[1]. Although shifting the code right might get you extra bonus
points, deep nesting seems to be encouraged! ;)

[1]
https://gitlab.freedesktop.org/panfrost/mali_kbase/blob/master/driver/product/kernel/drivers/gpu/arm/midgard/backend/gpu/mali_kbase_js_backend.c#L156

> 
> Only compile tested.

I've done some quick testing on a Firefly RK3288. But I don't have any
(handy) tests to trigger non-TRANSLATION_FAULT MMU faults.

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

Thanks,

Steve

> 
>  drivers/gpu/drm/panfrost/panfrost_mmu.c | 44 +++++++++++--------------
>  1 file changed, 19 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> index 763cfca886a7..4f2836bd9215 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -596,33 +596,27 @@ static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
>  		source_id = (fault_status >> 16);
>  
>  		/* Page fault only */
> -		if ((status & mask) == BIT(i)) {
> -			WARN_ON(exception_type < 0xC1 || exception_type > 0xC4);
> -
> +		ret = -1;
> +		if ((status & mask) == BIT(i) && (exception_type & 0xF8) == 0xC0)
>  			ret = panfrost_mmu_map_fault_addr(pfdev, i, addr);
> -			if (!ret) {
> -				mmu_write(pfdev, MMU_INT_CLEAR, BIT(i));
> -				status &= ~mask;
> -				continue;
> -			}
> -		}
>  
> -		/* terminal fault, print info about the fault */
> -		dev_err(pfdev->dev,
> -			"Unhandled Page fault in AS%d at VA 0x%016llX\n"
> -			"Reason: %s\n"
> -			"raw fault status: 0x%X\n"
> -			"decoded fault status: %s\n"
> -			"exception type 0x%X: %s\n"
> -			"access type 0x%X: %s\n"
> -			"source id 0x%X\n",
> -			i, addr,
> -			"TODO",
> -			fault_status,
> -			(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> -			exception_type, panfrost_exception_name(pfdev, exception_type),
> -			access_type, access_type_name(pfdev, fault_status),
> -			source_id);
> +		if (ret)
> +			/* terminal fault, print info about the fault */
> +			dev_err(pfdev->dev,
> +				"Unhandled Page fault in AS%d at VA 0x%016llX\n"
> +				"Reason: %s\n"
> +				"raw fault status: 0x%X\n"
> +				"decoded fault status: %s\n"
> +				"exception type 0x%X: %s\n"
> +				"access type 0x%X: %s\n"
> +				"source id 0x%X\n",
> +				i, addr,
> +				"TODO",
> +				fault_status,
> +				(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> +				exception_type, panfrost_exception_name(pfdev, exception_type),
> +				access_type, access_type_name(pfdev, fault_status),
> +				source_id);
>  
>  		mmu_write(pfdev, MMU_INT_CLEAR, mask);
>  
>
Tomeu Vizoso Feb. 24, 2020, 7:22 a.m. UTC | #2 
On Wed, 12 Feb 2020 at 21:22, Rob Herring <robh@kernel.org> wrote:
>
> From: Tomeu Vizoso <tomeu.vizoso@collabora.com>
>
> If the exception type isn't a translation fault, don't try to map and
> instead go straight to a terminal fault.
>
> Otherwise, we can get flooded by kernel warnings and further faults.
>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> I rewrote this some simplifying the code and somewhat following Steven's
> suggested. Still not using defines though. No defines here was good
> enough before IMO.
>
> Only compile tested.

Looks good, I also tested it on RK3399.

Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>

Thanks,

Tomeu

>  drivers/gpu/drm/panfrost/panfrost_mmu.c | 44 +++++++++++--------------
>  1 file changed, 19 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> index 763cfca886a7..4f2836bd9215 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -596,33 +596,27 @@ static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
>                 source_id = (fault_status >> 16);
>
>                 /* Page fault only */
> -               if ((status & mask) == BIT(i)) {
> -                       WARN_ON(exception_type < 0xC1 || exception_type > 0xC4);
> -
> +               ret = -1;
> +               if ((status & mask) == BIT(i) && (exception_type & 0xF8) == 0xC0)
>                         ret = panfrost_mmu_map_fault_addr(pfdev, i, addr);
> -                       if (!ret) {
> -                               mmu_write(pfdev, MMU_INT_CLEAR, BIT(i));
> -                               status &= ~mask;
> -                               continue;
> -                       }
> -               }
>
> -               /* terminal fault, print info about the fault */
> -               dev_err(pfdev->dev,
> -                       "Unhandled Page fault in AS%d at VA 0x%016llX\n"
> -                       "Reason: %s\n"
> -                       "raw fault status: 0x%X\n"
> -                       "decoded fault status: %s\n"
> -                       "exception type 0x%X: %s\n"
> -                       "access type 0x%X: %s\n"
> -                       "source id 0x%X\n",
> -                       i, addr,
> -                       "TODO",
> -                       fault_status,
> -                       (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> -                       exception_type, panfrost_exception_name(pfdev, exception_type),
> -                       access_type, access_type_name(pfdev, fault_status),
> -                       source_id);
> +               if (ret)
> +                       /* terminal fault, print info about the fault */
> +                       dev_err(pfdev->dev,
> +                               "Unhandled Page fault in AS%d at VA 0x%016llX\n"
> +                               "Reason: %s\n"
> +                               "raw fault status: 0x%X\n"
> +                               "decoded fault status: %s\n"
> +                               "exception type 0x%X: %s\n"
> +                               "access type 0x%X: %s\n"
> +                               "source id 0x%X\n",
> +                               i, addr,
> +                               "TODO",
> +                               fault_status,
> +                               (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> +                               exception_type, panfrost_exception_name(pfdev, exception_type),
> +                               access_type, access_type_name(pfdev, fault_status),
> +                               source_id);
>
>                 mmu_write(pfdev, MMU_INT_CLEAR, mask);
>
> --
> 2.20.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Alyssa Rosenzweig Feb. 24, 2020, 12:27 p.m. UTC | #3 
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>

On Wed, Feb 12, 2020 at 02:22:36PM -0600, Rob Herring wrote:
> From: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> 
> If the exception type isn't a translation fault, don't try to map and
> instead go straight to a terminal fault.
> 
> Otherwise, we can get flooded by kernel warnings and further faults.
> 
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> I rewrote this some simplifying the code and somewhat following Steven's 
> suggested. Still not using defines though. No defines here was good 
> enough before IMO.
> 
> Only compile tested.
> 
>  drivers/gpu/drm/panfrost/panfrost_mmu.c | 44 +++++++++++--------------
>  1 file changed, 19 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> index 763cfca886a7..4f2836bd9215 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -596,33 +596,27 @@ static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
>  		source_id = (fault_status >> 16);
>  
>  		/* Page fault only */
> -		if ((status & mask) == BIT(i)) {
> -			WARN_ON(exception_type < 0xC1 || exception_type > 0xC4);
> -
> +		ret = -1;
> +		if ((status & mask) == BIT(i) && (exception_type & 0xF8) == 0xC0)
>  			ret = panfrost_mmu_map_fault_addr(pfdev, i, addr);
> -			if (!ret) {
> -				mmu_write(pfdev, MMU_INT_CLEAR, BIT(i));
> -				status &= ~mask;
> -				continue;
> -			}
> -		}
>  
> -		/* terminal fault, print info about the fault */
> -		dev_err(pfdev->dev,
> -			"Unhandled Page fault in AS%d at VA 0x%016llX\n"
> -			"Reason: %s\n"
> -			"raw fault status: 0x%X\n"
> -			"decoded fault status: %s\n"
> -			"exception type 0x%X: %s\n"
> -			"access type 0x%X: %s\n"
> -			"source id 0x%X\n",
> -			i, addr,
> -			"TODO",
> -			fault_status,
> -			(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> -			exception_type, panfrost_exception_name(pfdev, exception_type),
> -			access_type, access_type_name(pfdev, fault_status),
> -			source_id);
> +		if (ret)
> +			/* terminal fault, print info about the fault */
> +			dev_err(pfdev->dev,
> +				"Unhandled Page fault in AS%d at VA 0x%016llX\n"
> +				"Reason: %s\n"
> +				"raw fault status: 0x%X\n"
> +				"decoded fault status: %s\n"
> +				"exception type 0x%X: %s\n"
> +				"access type 0x%X: %s\n"
> +				"source id 0x%X\n",
> +				i, addr,
> +				"TODO",
> +				fault_status,
> +				(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> +				exception_type, panfrost_exception_name(pfdev, exception_type),
> +				access_type, access_type_name(pfdev, fault_status),
> +				source_id);
>  
>  		mmu_write(pfdev, MMU_INT_CLEAR, mask);
>  
> -- 
> 2.20.1
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
index 763cfca886a7..4f2836bd9215 100644
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -596,33 +596,27 @@  static irqreturn_t panfrost_mmu_irq_handler_thread(int irq, void *data)
 		source_id = (fault_status >> 16);
 
 		/* Page fault only */
-		if ((status & mask) == BIT(i)) {
-			WARN_ON(exception_type < 0xC1 || exception_type > 0xC4);
-
+		ret = -1;
+		if ((status & mask) == BIT(i) && (exception_type & 0xF8) == 0xC0)
 			ret = panfrost_mmu_map_fault_addr(pfdev, i, addr);
-			if (!ret) {
-				mmu_write(pfdev, MMU_INT_CLEAR, BIT(i));
-				status &= ~mask;
-				continue;
-			}
-		}
 
-		/* terminal fault, print info about the fault */
-		dev_err(pfdev->dev,
-			"Unhandled Page fault in AS%d at VA 0x%016llX\n"
-			"Reason: %s\n"
-			"raw fault status: 0x%X\n"
-			"decoded fault status: %s\n"
-			"exception type 0x%X: %s\n"
-			"access type 0x%X: %s\n"
-			"source id 0x%X\n",
-			i, addr,
-			"TODO",
-			fault_status,
-			(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
-			exception_type, panfrost_exception_name(pfdev, exception_type),
-			access_type, access_type_name(pfdev, fault_status),
-			source_id);
+		if (ret)
+			/* terminal fault, print info about the fault */
+			dev_err(pfdev->dev,
+				"Unhandled Page fault in AS%d at VA 0x%016llX\n"
+				"Reason: %s\n"
+				"raw fault status: 0x%X\n"
+				"decoded fault status: %s\n"
+				"exception type 0x%X: %s\n"
+				"access type 0x%X: %s\n"
+				"source id 0x%X\n",
+				i, addr,
+				"TODO",
+				fault_status,
+				(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
+				exception_type, panfrost_exception_name(pfdev, exception_type),
+				access_type, access_type_name(pfdev, fault_status),
+				source_id);
 
 		mmu_write(pfdev, MMU_INT_CLEAR, mask);