Re: [PATCH] drm/i915: tune down Y tiling scanout warning

[Daniel Vetter <daniel@ffwll.ch>]

On Sat, Apr 06, 2013 at 11:54:56PM +0200, Daniel Vetter wrote:
> Userspace can easily hit this and does since Ville added a new evil
> igt testcase in:
> 
> commit 069e35e0fc3785faa562adcfd2dd7bbed4cb1dea
> Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Date:   Mon Mar 4 15:34:06 2013 +0200
> 
>     kms_flip: Add flip-vs-bad-tiling test
> 
> v2: Fix the spelling in the added comment (Chris).
> 
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

I've picked this up for next with a reference to the bug QA filed.
-Daniel

> ---
>  drivers/gpu/drm/i915/intel_display.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 1b2c744..0e799ea 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -1907,8 +1907,10 @@ intel_pin_and_fence_fb_obj(struct drm_device *dev,
>  		alignment = 0;
>  		break;
>  	case I915_TILING_Y:
> -		/* FIXME: Is this true? */
> -		DRM_ERROR("Y tiled not allowed for scan out buffers\n");
> +		/* Despite that we check this in framebuffer_init userspace can
> +		 * screw us over and change the tiling after the fact. Only
> +		 * pinned buffers can't change their tiling. */
> +		DRM_DEBUG_DRIVER("Y tiled not allowed for scan out buffers\n");
>  		return -EINVAL;
>  	default:
>  		BUG();
> -- 
> 1.7.10.4
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch