diff --git a/plat/allwinner/common/include/platform_def.h b/plat/allwinner/common/include/platform_def.h
index 1b660e1..975cc48 100644
--- a/plat/allwinner/common/include/platform_def.h
+++ b/plat/allwinner/common/include/platform_def.h
@@ -40,6 +40,9 @@
 #define MAX_MMAP_REGIONS		(3 + PLATFORM_MMAP_REGIONS)
 #define MAX_XLAT_TABLES			1
 
+#define PLAT_CSS_SCP_COM_SHARED_MEM_BASE \
+	(SUNXI_SRAM_A2_BASE + SUNXI_SRAM_A2_SIZE - 0x200)
+
 #define PLAT_MAX_PWR_LVL_STATES		U(2)
 #define PLAT_MAX_RET_STATE		U(1)
 #define PLAT_MAX_OFF_STATE		U(2)