diff --git a/SConstruct b/SConstruct
index 57134b6863..c4782691ff 100755
--- a/SConstruct
+++ b/SConstruct
@@ -264,6 +264,8 @@ kconfig_actions = (
     'guiconfig',
     'listnewconfig',
     'menuconfig',
+    'oldconfig',
+    'olddefconfig',
     'savedefconfig',
     'setconfig',
 )
@@ -317,6 +319,22 @@ Kconfig tools:
         scons menuconfig build/foo/bar
 
 
+        oldconfig:
+        Update an existing config by adding settings for new options. This is
+        the same as the olddefconfig tool, except it asks what values you want
+        for the new settings.
+
+        scons oldconfig build/foo/bar
+
+
+        olddefconfig:
+        Update an existing config by adding settings for new options. This is
+        the same as the oldconfig tool, except it uses the default for any new
+        setting.
+
+        scons olddefconfig build/foo/bar
+
+
         savedefconfig:
         Save a defconfig file which would give rise to the current config.
         For instance, you could use menuconfig to set up a config how you want
@@ -868,6 +886,11 @@ for variant_path in variant_paths:
         elif kconfig_action == 'menuconfig':
             kconfig.menuconfig(env, kconfig_file.abspath, config_file.abspath,
                     variant_path)
+        elif kconfig_action == 'oldconfig':
+            kconfig.oldconfig(env, kconfig_file.abspath, config_file.abspath)
+        elif kconfig_action == 'olddefconfig':
+            kconfig.olddefconfig(env, kconfig_file.abspath,
+                    config_file.abspath)
         elif kconfig_action == 'savedefconfig':
             if len(kconfig_args) != 1:
                 error('Usage: scons defconfig <build dir> <defconfig file>')
diff --git a/site_scons/gem5_scons/kconfig.py b/site_scons/gem5_scons/kconfig.py
index 347e11277d..42b2eec482 100644
--- a/site_scons/gem5_scons/kconfig.py
+++ b/site_scons/gem5_scons/kconfig.py
@@ -33,6 +33,8 @@ _kconfig_helpers = {
     "GUICONFIG_PY": "guiconfig.py",
     "LISTNEWCONFIG_PY": "listnewconfig.py",
     "MENUCONFIG_PY": "menuconfig.py",
+    "OLDCONFIG_PY": "oldconfig.py",
+    "OLDDEFCONFIG_PY": "olddefconfig.py",
     "SAVEDEFCONFIG_PY": "savedefconfig.py",
     "SETCONFIG_PY": "setconfig.py",
 }
@@ -118,6 +120,24 @@ def listnewconfig(env, base_kconfig, config_path):
         error("Failed to run listnewconfig")
 
 
+def oldconfig(env, base_kconfig, config_path):
+    """
+    Interface of handling oldconfig.py of Kconfiglib
+    """
+    kconfig_env = _prep_env(env, base_kconfig, config_path)
+    if kconfig_env.Execute('"${OLDCONFIG_PY}" "${BASE_KCONFIG}"') != 0:
+        error("Failed to run oldconfig")
+
+
+def olddefconfig(env, base_kconfig, config_path):
+    """
+    Interface of handling olddefconfig.py of Kconfiglib
+    """
+    kconfig_env = _prep_env(env, base_kconfig, config_path)
+    if kconfig_env.Execute('"${OLDDEFCONFIG_PY}" "${BASE_KCONFIG}"') != 0:
+        error("Failed to run oldconfig")
+
+
 def menuconfig(
     env, base_kconfig, config_path, main_menu_text, style="aquatic"
 ):