diff --git a/src/soc/intel/alderlake/systemagent.c b/src/soc/intel/alderlake/systemagent.c
index be0c6996a4..bbc421b0cb 100644
--- a/src/soc/intel/alderlake/systemagent.c
+++ b/src/soc/intel/alderlake/systemagent.c
@@ -116,7 +116,7 @@ void soc_add_configurable_mmio_resources(struct device *dev, int *resource_cnt)
 	}
 
 	/* TSEG */
-	size = sa_get_tseg_size();
+	size = CONFIG_SMM_TSEG_SIZE;
 	tseg_base = sa_get_tseg_base();
 	if (size > 0)
 		set_mmio_resource(&(cfg_rsrc[count++]), tseg_base, size, "TSEG");
diff --git a/src/soc/intel/common/block/include/intelblocks/systemagent.h b/src/soc/intel/common/block/include/intelblocks/systemagent.h
index a3ae8c38bf..5047f1d9aa 100644
--- a/src/soc/intel/common/block/include/intelblocks/systemagent.h
+++ b/src/soc/intel/common/block/include/intelblocks/systemagent.h
@@ -91,8 +91,6 @@ uintptr_t sa_get_tolud_base(void);
 uintptr_t sa_get_gsm_base(void);
 /* API to get TSEG base address */
 uintptr_t sa_get_tseg_base(void);
-/* API to get TSEG size */
-size_t sa_get_tseg_size(void);
 /* API to lock PAM registers */
 void sa_lock_pam(void);
 /* API to get MMIO config size */
diff --git a/src/soc/intel/common/block/systemagent/memmap.c b/src/soc/intel/common/block/systemagent/memmap.c
index 3b0fb6e8ae..9a3971098f 100644
--- a/src/soc/intel/common/block/systemagent/memmap.c
+++ b/src/soc/intel/common/block/systemagent/memmap.c
@@ -54,7 +54,7 @@
 void smm_region(uintptr_t *start, size_t *size)
 {
 	*start = sa_get_tseg_base();
-	*size = sa_get_tseg_size();
+	*size = CONFIG_SMM_TSEG_SIZE;
 }
 
 void fill_postcar_frame(struct postcar_frame *pcf)
diff --git a/src/soc/intel/common/block/systemagent/systemagent_early.c b/src/soc/intel/common/block/systemagent/systemagent_early.c
index aecdfbb429..993d008eb6 100644
--- a/src/soc/intel/common/block/systemagent/systemagent_early.c
+++ b/src/soc/intel/common/block/systemagent/systemagent_early.c
@@ -146,11 +146,6 @@ uintptr_t sa_get_tseg_base(void)
 	return ALIGN_DOWN(pci_read_config32(SA_DEV_ROOT, TSEG), 1*MiB);
 }
 
-size_t sa_get_tseg_size(void)
-{
-	return sa_get_gsm_base() - sa_get_tseg_base();
-}
-
 union dpr_register txt_get_chipset_dpr(void)
 {
 	return (union dpr_register) { .raw = pci_read_config32(SA_DEV_ROOT, DPR) };
diff --git a/src/soc/intel/meteorlake/systemagent.c b/src/soc/intel/meteorlake/systemagent.c
index bb841aa60b..9dc771f6e2 100644
--- a/src/soc/intel/meteorlake/systemagent.c
+++ b/src/soc/intel/meteorlake/systemagent.c
@@ -108,7 +108,7 @@ void soc_add_configurable_mmio_resources(struct device *dev, int *resource_cnt)
 	}
 
 	/* TSEG */
-	size = sa_get_tseg_size();
+	size = CONFIG_SMM_TSEG_SIZE;
 	tseg_base = sa_get_tseg_base();
 	if (size > 0)
 		set_mmio_resource(&(cfg_rsrc[count++]), tseg_base, size, "TSEG");
diff --git a/src/soc/intel/pantherlake/systemagent.c b/src/soc/intel/pantherlake/systemagent.c
index c1a081cb1b..f88aedb95c 100644
--- a/src/soc/intel/pantherlake/systemagent.c
+++ b/src/soc/intel/pantherlake/systemagent.c
@@ -105,7 +105,7 @@ void soc_add_configurable_mmio_resources(struct device *dev, int *resource_cnt)
 	}
 
 	/* TSEG */
-	size = sa_get_tseg_size();
+	size = CONFIG_SMM_TSEG_SIZE;
 	tseg_base = sa_get_tseg_base();
 	if (size > 0)
 		set_mmio_resource(&(cfg_rsrc[count++]), tseg_base, size, "TSEG");