diff --git a/docs/porting-guide.rst b/docs/porting-guide.rst
index 9ca2aa9..98aa76d 100644
--- a/docs/porting-guide.rst
+++ b/docs/porting-guide.rst
@@ -1001,7 +1001,7 @@
 This function returns the size normal-world DCE of the platform.
 
 Function : plat_drtm_get_imp_def_dlme_region_size()
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 ::
 
@@ -1012,7 +1012,7 @@
 of the platform.
 
 Function : plat_drtm_get_tcb_hash_table_size()
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 ::
 
@@ -1021,8 +1021,18 @@
 
 This function returns the size of TCB hash table of the platform.
 
+Function : plat_drtm_get_acpi_tables_region_size()
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : void
+    Return   : uint64_t
+
+This function returns the size of ACPI tables region of the platform.
+
 Function : plat_drtm_get_tcb_hash_features()
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 ::
 
diff --git a/include/plat/common/plat_drtm.h b/include/plat/common/plat_drtm.h
index 07545a6..4f69210 100644
--- a/include/plat/common/plat_drtm.h
+++ b/include/plat/common/plat_drtm.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2024, Arm Limited. All rights reserved.
+ * Copyright (c) 2022-2025, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -59,6 +59,8 @@
 uint64_t plat_drtm_get_tcb_hash_table_size(void);
 uint64_t plat_drtm_get_imp_def_dlme_region_size(void);
 uint64_t plat_drtm_get_tcb_hash_features(void);
+uint64_t plat_drtm_get_acpi_tables_region_size(void);
+
 
 /* DRTM error handling functions */
 int plat_set_drtm_error(uint64_t error_code);