[Intel-gfx] [PATCH] drm/i915: Dont enable CS_PARSER_ERROR interrupts at all

[Daniel Vetter]

On Wed, Apr 01, 2015 at 01:43:46PM +0200, Daniel Vetter wrote:
> We stopped handling them in
> 
> commit aaecdf611a05cac26a94713bad25297e60225c29
> Author: Daniel Vetter <daniel.vetter at ffwll.ch>
> Date:   Tue Nov 4 15:52:22 2014 +0100
> 
>     drm/i915: Stop gathering error states for CS error interrupts
> 
> but just clearing is apparently not enough: A sufficiently dead gpu
> left behind by firmware (*cough* coreboot *cough*) can keep the gpu in
> an endless loop of such interrupts, eventually leading to the nmi
> firing. And definitely to what looks like a machine hang.
> 
> Since we don't even enable these interrupts on gen5+ let's do the same
> on earlier platforms.
> 
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=93171
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>

Tested-by: Mono <mono-for-kernel-org at donderklumpen.de>
Tested-by: info at gluglug.org.uk
Cc: stable at vger.kernel.org


> ---
>  drivers/gpu/drm/i915/i915_irq.c | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index 14ecb4d13a1a..6d494432b19f 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -3598,14 +3598,12 @@ static int i8xx_irq_postinstall(struct drm_device *dev)
>  		~(I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |
>  		  I915_DISPLAY_PIPE_B_EVENT_INTERRUPT |
>  		  I915_DISPLAY_PLANE_A_FLIP_PENDING_INTERRUPT |
> -		  I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT |
> -		  I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT);
> +		  I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT);
>  	I915_WRITE16(IMR, dev_priv->irq_mask);
>  
>  	I915_WRITE16(IER,
>  		     I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |
>  		     I915_DISPLAY_PIPE_B_EVENT_INTERRUPT |
> -		     I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT |
>  		     I915_USER_INTERRUPT);
>  	POSTING_READ16(IER);
>  
> @@ -3767,14 +3765,12 @@ static int i915_irq_postinstall(struct drm_device *dev)
>  		  I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |
>  		  I915_DISPLAY_PIPE_B_EVENT_INTERRUPT |
>  		  I915_DISPLAY_PLANE_A_FLIP_PENDING_INTERRUPT |
> -		  I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT |
> -		  I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT);
> +		  I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT);
>  
>  	enable_mask =
>  		I915_ASLE_INTERRUPT |
>  		I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |
>  		I915_DISPLAY_PIPE_B_EVENT_INTERRUPT |
> -		I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT |
>  		I915_USER_INTERRUPT;
>  
>  	if (I915_HAS_HOTPLUG(dev)) {
> -- 
> 2.1.4
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch