diff --git a/src/soc/intel/alderlake/Kconfig b/src/soc/intel/alderlake/Kconfig
index 89d0c93..dc7d32b 100644
--- a/src/soc/intel/alderlake/Kconfig
+++ b/src/soc/intel/alderlake/Kconfig
@@ -207,6 +207,12 @@
 	default 0 if SOC_INTEL_ALDERLAKE_PCH_N
 	default 3 if SOC_INTEL_ALDERLAKE_PCH_P
 
+config MAX_TBT_ROOT_PORTS
+	int
+	default 0 if SOC_INTEL_ALDERLAKE_PCH_N
+	default 2 if SOC_INTEL_ALDERLAKE_PCH_M
+	default 4 if SOC_INTEL_ALDERLAKE_PCH_P
+
 config MAX_ROOT_PORTS
 	int
 	default MAX_PCH_ROOT_PORTS