diff --git a/src/soc/amd/picasso/ramtop.c b/src/soc/amd/picasso/ramtop.c
index 344b7f7cc5..6b28ec7dd6 100644
--- a/src/soc/amd/picasso/ramtop.c
+++ b/src/soc/amd/picasso/ramtop.c
@@ -130,6 +130,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		clear_tvalid();
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/amd/stoneyridge/ramtop.c b/src/soc/amd/stoneyridge/ramtop.c
index 3a23df6c1a..26d84cef12 100644
--- a/src/soc/amd/stoneyridge/ramtop.c
+++ b/src/soc/amd/stoneyridge/ramtop.c
@@ -130,6 +130,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		clear_tvalid();
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/apollolake/memmap.c b/src/soc/intel/apollolake/memmap.c
index 7494481fa5..17dfb3f545 100644
--- a/src/soc/intel/apollolake/memmap.c
+++ b/src/soc/intel/apollolake/memmap.c
@@ -68,6 +68,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = cache_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/braswell/memmap.c b/src/soc/intel/braswell/memmap.c
index 01594eabb0..51b7b36db4 100644
--- a/src/soc/intel/braswell/memmap.c
+++ b/src/soc/intel/braswell/memmap.c
@@ -62,6 +62,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = cache_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/cannonlake/memmap.c b/src/soc/intel/cannonlake/memmap.c
index b5b538c1ec..004e35c98c 100644
--- a/src/soc/intel/cannonlake/memmap.c
+++ b/src/soc/intel/cannonlake/memmap.c
@@ -72,6 +72,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = ied_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/denverton_ns/memmap.c b/src/soc/intel/denverton_ns/memmap.c
index d4265e994e..9507d7f238 100644
--- a/src/soc/intel/denverton_ns/memmap.c
+++ b/src/soc/intel/denverton_ns/memmap.c
@@ -96,6 +96,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = cache_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/icelake/memmap.c b/src/soc/intel/icelake/memmap.c
index 046774f0c6..13eb947935 100644
--- a/src/soc/intel/icelake/memmap.c
+++ b/src/soc/intel/icelake/memmap.c
@@ -70,6 +70,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = ied_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}
 
diff --git a/src/soc/intel/skylake/memmap.c b/src/soc/intel/skylake/memmap.c
index d6ab908c37..963a5003e8 100644
--- a/src/soc/intel/skylake/memmap.c
+++ b/src/soc/intel/skylake/memmap.c
@@ -74,6 +74,8 @@ int smm_subregion(int sub, uintptr_t *start, size_t *size)
 		sub_size = ied_size;
 		break;
 	default:
+		*start = 0;
+		*size = 0;
 		return -1;
 	}