diff --git a/plat/nvidia/tegra/include/t186/tegra_def.h b/plat/nvidia/tegra/include/t186/tegra_def.h
index 19d1250..20a7994 100644
--- a/plat/nvidia/tegra/include/t186/tegra_def.h
+++ b/plat/nvidia/tegra/include/t186/tegra_def.h
@@ -141,6 +141,10 @@
 #define MC_SECURITY_CFG1_0		U(0x74)
 #define MC_SECURITY_CFG3_0		U(0x9BC)
 
+#define MC_SECURITY_BOM_MASK		(U(0xFFF) << 20)
+#define MC_SECURITY_SIZE_MB_MASK	(U(0x1FFF) << 0)
+#define MC_SECURITY_BOM_HI_MASK		(U(0x3) << 0)
+
 /* Video Memory carveout configuration registers */
 #define MC_VIDEO_PROTECT_BASE_HI	U(0x978)
 #define MC_VIDEO_PROTECT_BASE_LO	U(0x648)