diff --git a/litex/build/xilinx/platform.py b/litex/build/xilinx/platform.py
index e17ad4f9e..2143df58b 100644
--- a/litex/build/xilinx/platform.py
+++ b/litex/build/xilinx/platform.py
@@ -1,3 +1,5 @@
+import os
+
 from litex.build.generic_platform import GenericPlatform
 from litex.build.xilinx import common, vivado, ise