[Intel-gfx] [PATCH] drm: Aggressively disable vblanks

[Mario Kleiner]

On Dec 27, 2010, at 12:16 PM, Ville Syrjälä wrote:

> On Mon, Dec 27, 2010 at 12:58:10AM +0100, Mario Kleiner wrote:
>
>> 2. There are gpu's firing spurious vblank irq's as soon as you enable
>> irq's
>
> You're sure this isn't simply a matter of the driver forgetting to ack
> the irq just before enabling it?
>

Good point. This was on radeon. I can't remember for certain if it  
happened always, or only frequently. I can check that later this week  
when i'm back at the test machine.

Anyway, it's good to be robust against such problems, regardless if  
it is gpu quirks or driver bugs. The current implementation would  
filter the redundant vblank irq and DRM_DEBUG a message if the  
drm.debug parameter is set.

thanks,
-mario

> -- 
> Ville Syrjälä
> syrjala at sci.fi
> http://www.sci.fi/~syrjala/

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Mario Kleiner
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