[LICENSE] Copyright -> SPDX-FileCopyrightText:
diff --git a/verilog/gl/gpio_control_block.v b/verilog/gl/gpio_control_block.v
index 66e4737..bf9db51 100644
--- a/verilog/gl/gpio_control_block.v
+++ b/verilog/gl/gpio_control_block.v
@@ -1,4 +1,4 @@
-// Copyright 2020 Efabless Corporation
+// SPDX-FileCopyrightText: 2020 Efabless Corporation
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.