diff --git a/sdk/xtdk/bltypes.h b/sdk/xtdk/bltypes.h
index 60d52e5..78ea37f 100644
--- a/sdk/xtdk/bltypes.h
+++ b/sdk/xtdk/bltypes.h
@@ -17,6 +17,13 @@
 #define XTBL_LOADER_DIRECTORY                                       L"\\EFI\\BOOT\\XTLDR\\"
 #define XTBL_THEMES_DIRECTORY                                       L"\\EFI\\BOOT\\XTLDR\\THEMES\\"
 
+/* EFI XT boot devices */
+#define XTBL_BOOT_DEVICE_UNKNOWN                                    0x00
+#define XTBL_BOOT_DEVICE_CDROM                                      0x01
+#define XTBL_BOOT_DEVICE_FLOPPY                                     0x02
+#define XTBL_BOOT_DEVICE_HARDDISK                                   0x03
+#define XTBL_BOOT_DEVICE_RAMDISK                                    0x04
+
 /* XTLDR Debug Port type definitions */
 #define XTBL_DEBUGPORT_SCREEN                                       1
 #define XTBL_DEBUGPORT_SERIAL                                       2