drm/virtio: implement blob resources: probe for the feature.

Let's proble for VIRTIO_GPU_F_RESOURCE_BLOB.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-8-gurchetansingh@chromium.org

drivers/gpu/drm/virtio/virtgpu_debugfs.c

@@ -49,6 +49,7 @@ static int virtio_gpu_features(struct seq_file *m, void *data)
 	virtio_add_bool(m, "edid", vgdev->has_edid);
 	virtio_add_bool(m, "indirect", vgdev->has_indirect);
 	virtio_add_bool(m, "resource uuid", vgdev->has_resource_assign_uuid);
+	virtio_add_bool(m, "blob resources", vgdev->has_resource_blob);
 	virtio_add_int(m, "cap sets", vgdev->num_capsets);
 	virtio_add_int(m, "scanouts", vgdev->num_scanouts);
 	return 0;

drivers/gpu/drm/virtio/virtgpu_drv.c

@@ -166,6 +166,7 @@ static unsigned int features[] = {
 #endif
 	VIRTIO_GPU_F_EDID,
 	VIRTIO_GPU_F_RESOURCE_UUID,
+	VIRTIO_GPU_F_RESOURCE_BLOB,
 };
 static struct virtio_driver virtio_gpu_driver = {
 	.feature_table = features,

drivers/gpu/drm/virtio/virtgpu_drv.h

@@ -208,6 +208,7 @@ struct virtio_gpu_device {
 	bool has_edid;
 	bool has_indirect;
 	bool has_resource_assign_uuid;
+	bool has_resource_blob;
 
 	struct work_struct config_changed_work;
 

drivers/gpu/drm/virtio/virtgpu_kms.c

@@ -152,10 +152,14 @@ int virtio_gpu_init(struct drm_device *dev)
 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_UUID)) {
 		vgdev->has_resource_assign_uuid = true;
 	}
+	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_BLOB)) {
+		vgdev->has_resource_blob = true;
+	}
 
-	DRM_INFO("features: %cvirgl %cedid\n",
+	DRM_INFO("features: %cvirgl %cedid %cresource_blob\n",
 		 vgdev->has_virgl_3d    ? '+' : '-',
-		 vgdev->has_edid     ? '+' : '-');
+		 vgdev->has_edid        ? '+' : '-',
+		 vgdev->has_resource_blob ? '+' : '-');
 
 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
 	if (ret) {