drm/i915: tune down Y tiling scanout warning

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>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=63246
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b884932..04d91cc 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2002,8 +2002,10 @@ 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();