diff --git a/hal/halx86/include/bus.h b/hal/halx86/include/bus.h
index 81b5e5f1b07..3e07190f470 100644
--- a/hal/halx86/include/bus.h
+++ b/hal/halx86/include/bus.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#define PCI_ADDRESS_MEMORY_SPACE            0x00000000
+
 //
 // Helper Macros
 //