diff --git a/litedram/init.py b/litedram/init.py
index 4916a42..22c32d3 100644
--- a/litedram/init.py
+++ b/litedram/init.py
@@ -670,6 +670,7 @@ def get_sdram_phy_c_header(phy_settings, timing_settings):
     r += "#define SDRAM_PHY_"+phytype+"\n"
     r += "#define SDRAM_PHY_XDR "+str(1 if phy_settings.memtype == "SDR" else 2) + "\n"
     r += "#define SDRAM_PHY_DATABITS "+str(phy_settings.databits) + "\n"
+    r += "#define SDRAM_PHY_DFI_DATABITS "+str(phy_settings.dfi_databits) + "\n"
     r += "#define SDRAM_PHY_PHASES "+str(nphases)+"\n"
     if phy_settings.cl is not None:
         r += "#define SDRAM_PHY_CL "+str(phy_settings.cl)+"\n"