drm/i915: Reject 90/270 degree rotated initial fbs

We don't currently handle the initial fb readout correctly
for 90/270 degree rotated scanout. Reject it.

Cc: stable@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201020194330.28568-1-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/display/intel_display.c

@@ -10802,6 +10802,10 @@ skl_get_initial_plane_config(struct intel_crtc *crtc,
 	    val & PLANE_CTL_FLIP_HORIZONTAL)
 		plane_config->rotation |= DRM_MODE_REFLECT_X;
 
+	/* 90/270 degree rotation would require extra work */
+	if (drm_rotation_90_or_270(plane_config->rotation))
+		goto error;
+
 	base = intel_de_read(dev_priv, PLANE_SURF(pipe, plane_id)) & 0xfffff000;
 	plane_config->base = base;