drm/i915: Add DEBUG messages to all intel_create_user_framebuffer error paths

This proves to be very useful when investigating why code suddenly
started failing.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -8598,19 +8598,30 @@ int intel_framebuffer_init(struct drm_device *dev,
 {
 	int ret;
 
-	if (obj->tiling_mode == I915_TILING_Y)
+	if (obj->tiling_mode == I915_TILING_Y) {
+		DRM_DEBUG("hardware does not support tiling Y\n");
 		return -EINVAL;
+	}
 
-	if (mode_cmd->pitches[0] & 63)
+	if (mode_cmd->pitches[0] & 63) {
+		DRM_DEBUG("pitch (%d) must be at least 64 byte aligned\n",
+			  mode_cmd->pitches[0]);
 		return -EINVAL;
+	}
 
 	/* FIXME <= Gen4 stride limits are bit unclear */
-	if (mode_cmd->pitches[0] > 32768)
+	if (mode_cmd->pitches[0] > 32768) {
+		DRM_DEBUG("pitch (%d) must be at less than 32768\n",
+			  mode_cmd->pitches[0]);
 		return -EINVAL;
+	}
 
 	if (obj->tiling_mode != I915_TILING_NONE &&
-	    mode_cmd->pitches[0] != obj->stride)
+	    mode_cmd->pitches[0] != obj->stride) {
+		DRM_DEBUG("pitch (%d) must match tiling stride (%d)\n",
+			  mode_cmd->pitches[0], obj->stride);
 		return -EINVAL;
+	}
 
 	/* Reject formats not supported by any plane early. */
 	switch (mode_cmd->pixel_format) {
@@ -8621,8 +8632,10 @@ int intel_framebuffer_init(struct drm_device *dev,
 		break;
 	case DRM_FORMAT_XRGB1555:
 	case DRM_FORMAT_ARGB1555:
-		if (INTEL_INFO(dev)->gen > 3)
+		if (INTEL_INFO(dev)->gen > 3) {
+			DRM_DEBUG("invalid format: 0x%08x\n", mode_cmd->pixel_format);
 			return -EINVAL;
+		}
 		break;
 	case DRM_FORMAT_XBGR8888:
 	case DRM_FORMAT_ABGR8888:
@@ -8630,18 +8643,22 @@ int intel_framebuffer_init(struct drm_device *dev,
 	case DRM_FORMAT_ARGB2101010:
 	case DRM_FORMAT_XBGR2101010:
 	case DRM_FORMAT_ABGR2101010:
-		if (INTEL_INFO(dev)->gen < 4)
+		if (INTEL_INFO(dev)->gen < 4) {
+			DRM_DEBUG("invalid format: 0x%08x\n", mode_cmd->pixel_format);
 			return -EINVAL;
+		}
 		break;
 	case DRM_FORMAT_YUYV:
 	case DRM_FORMAT_UYVY:
 	case DRM_FORMAT_YVYU:
 	case DRM_FORMAT_VYUY:
-		if (INTEL_INFO(dev)->gen < 5)
+		if (INTEL_INFO(dev)->gen < 5) {
+			DRM_DEBUG("invalid format: 0x%08x\n", mode_cmd->pixel_format);
 			return -EINVAL;
+		}
 		break;
 	default:
-		DRM_DEBUG_KMS("unsupported pixel format 0x%08x\n", mode_cmd->pixel_format);
+		DRM_DEBUG("unsupported pixel format 0x%08x\n", mode_cmd->pixel_format);
 		return -EINVAL;
 	}