diff --git a/plat/mediatek/mt8186/include/platform_def.h b/plat/mediatek/mt8186/include/platform_def.h
index 90096e9..b8b877a 100644
--- a/plat/mediatek/mt8186/include/platform_def.h
+++ b/plat/mediatek/mt8186/include/platform_def.h
@@ -47,6 +47,7 @@
 #define IOCFG_RB_BASE		(IO_PHYS + 0x00002A00)
 #define IOCFG_RT_BASE		(IO_PHYS + 0x00002C00)
 #define APMIXEDSYS		(IO_PHYS + 0x0000C000)
+#define DVFSRC_BASE		(IO_PHYS + 0x00012000)
 #define MMSYS_BASE		(IO_PHYS + 0x04000000)
 #define MDPSYS_BASE		(IO_PHYS + 0x0B000000)