diff --git a/src/northbridge/intel/haswell/Kconfig b/src/northbridge/intel/haswell/Kconfig
index 5801658..28b7551 100644
--- a/src/northbridge/intel/haswell/Kconfig
+++ b/src/northbridge/intel/haswell/Kconfig
@@ -36,6 +36,10 @@
 config MMCONF_BASE_ADDRESS
 	default 0xf0000000
 
+config MMCONF_BUS_NUMBER
+	int
+	default 64
+
 config DCACHE_RAM_BASE
 	hex
 	default 0xff7c0000