diff --git a/litex/soc/cores/code_8b10b.py b/litex/soc/cores/code_8b10b.py
index 74e4e3f83..0d4fc5e24 100644
--- a/litex/soc/cores/code_8b10b.py
+++ b/litex/soc/cores/code_8b10b.py
@@ -28,6 +28,9 @@ from litex.soc.interconnect import stream
 
 # Helpers ------------------------------------------------------------------------------------------
 
+def K(x, y):
+    return (y << 5) | x
+
 def disparity(word, nbits):
     n0 = 0
     n1 = 0