diff --git a/boards/adafruit-clue/Makefile.features b/boards/adafruit-clue/Makefile.features
index 912b45773c..eb54e9cce9 100644
--- a/boards/adafruit-clue/Makefile.features
+++ b/boards/adafruit-clue/Makefile.features
@@ -12,7 +12,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/adafruit-itsybitsy-m4/Makefile.features b/boards/adafruit-itsybitsy-m4/Makefile.features
index c0d3578538..057787eafb 100644
--- a/boards/adafruit-itsybitsy-m4/Makefile.features
+++ b/boards/adafruit-itsybitsy-m4/Makefile.features
@@ -17,5 +17,5 @@ FEATURES_PROVIDED += periph_usbdev
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/adafruit-itsybitsy-m4.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/adafruit-itsybitsy-m4.config
 endif
diff --git a/boards/adafruit-itsybitsy-nrf52/Makefile.features b/boards/adafruit-itsybitsy-nrf52/Makefile.features
index 912b45773c..eb54e9cce9 100644
--- a/boards/adafruit-itsybitsy-nrf52/Makefile.features
+++ b/boards/adafruit-itsybitsy-nrf52/Makefile.features
@@ -12,7 +12,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/arduino-nano-33-ble/Makefile.features b/boards/arduino-nano-33-ble/Makefile.features
index 912b45773c..eb54e9cce9 100644
--- a/boards/arduino-nano-33-ble/Makefile.features
+++ b/boards/arduino-nano-33-ble/Makefile.features
@@ -12,7 +12,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/bastwan/Makefile.features b/boards/bastwan/Makefile.features
index 9536f53ea7..6fe3facd51 100644
--- a/boards/bastwan/Makefile.features
+++ b/boards/bastwan/Makefile.features
@@ -19,5 +19,5 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/bastwan.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/bastwan.config
 endif
diff --git a/boards/common/iotlab/Makefile.features b/boards/common/iotlab/Makefile.features
index dcabc9af10..ba0bff2db2 100644
--- a/boards/common/iotlab/Makefile.features
+++ b/boards/common/iotlab/Makefile.features
@@ -13,4 +13,4 @@ FEATURES_PROVIDED += periph_uart
 FEATURES_PROVIDED += riotboot
 
 # iotlab boards provide a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/iotlab/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/iotlab/clock.config
diff --git a/boards/common/particle-mesh/Makefile.features b/boards/common/particle-mesh/Makefile.features
index a52459e965..98a4aaa362 100644
--- a/boards/common/particle-mesh/Makefile.features
+++ b/boards/common/particle-mesh/Makefile.features
@@ -15,7 +15,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/common/weact-f4x1cx/Makefile.features b/boards/common/weact-f4x1cx/Makefile.features
index 0f65aee573..6216610ca9 100644
--- a/boards/common/weact-f4x1cx/Makefile.features
+++ b/boards/common/weact-f4x1cx/Makefile.features
@@ -14,4 +14,4 @@ FEATURES_PROVIDED += periph_usbdev
 FEATURES_PROVIDED += highlevel_stdio
 
 # weact-f4x1cx boards provide a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/weact-f4x1cx/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/weact-f4x1cx/clock.config
diff --git a/boards/f4vi1/Makefile.features b/boards/f4vi1/Makefile.features
index eb610fcaeb..941f156e30 100644
--- a/boards/f4vi1/Makefile.features
+++ b/boards/f4vi1/Makefile.features
@@ -7,4 +7,4 @@ FEATURES_PROVIDED += periph_timer
 FEATURES_PROVIDED += periph_uart
 
 # f4vi1 provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/f4vi1/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/f4vi1/clock.config
diff --git a/boards/feather-nrf52840/Makefile.features b/boards/feather-nrf52840/Makefile.features
index 912b45773c..eb54e9cce9 100644
--- a/boards/feather-nrf52840/Makefile.features
+++ b/boards/feather-nrf52840/Makefile.features
@@ -12,7 +12,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/msbiot/Makefile.features b/boards/msbiot/Makefile.features
index d4346ad56e..55ac53bdfc 100644
--- a/boards/msbiot/Makefile.features
+++ b/boards/msbiot/Makefile.features
@@ -12,4 +12,4 @@ FEATURES_PROVIDED += periph_timer
 FEATURES_PROVIDED += periph_uart
 
 # msbiot provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/msbiot/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/msbiot/clock.config
diff --git a/boards/mulle/Makefile.features b/boards/mulle/Makefile.features
index ba8aa8fa3d..58744387ea 100644
--- a/boards/mulle/Makefile.features
+++ b/boards/mulle/Makefile.features
@@ -22,5 +22,5 @@ FEATURES_PROVIDED += periph_uart
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/mulle.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/mulle.config
 endif
diff --git a/boards/nrf52840-mdk-dongle/Makefile.features b/boards/nrf52840-mdk-dongle/Makefile.features
index a4fe12567f..d84ce78dc5 100644
--- a/boards/nrf52840-mdk-dongle/Makefile.features
+++ b/boards/nrf52840-mdk-dongle/Makefile.features
@@ -11,7 +11,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/nrf52840dongle/Makefile.features b/boards/nrf52840dongle/Makefile.features
index 8f0f1f65a9..4e5af160fb 100644
--- a/boards/nrf52840dongle/Makefile.features
+++ b/boards/nrf52840dongle/Makefile.features
@@ -15,7 +15,7 @@ FEATURES_PROVIDED += highlevel_stdio
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
+  KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/common/nrf52/nrf52_bootloader.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/pinetime/Makefile.features b/boards/pinetime/Makefile.features
index 8eb9b26f79..e3296d8ec1 100644
--- a/boards/pinetime/Makefile.features
+++ b/boards/pinetime/Makefile.features
@@ -9,7 +9,7 @@ FEATURES_PROVIDED += vdd_lc_filter_reg1
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/pinetime.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/pinetime.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/pyboard/Makefile.features b/boards/pyboard/Makefile.features
index 08918f30d4..841e68ca3b 100644
--- a/boards/pyboard/Makefile.features
+++ b/boards/pyboard/Makefile.features
@@ -11,4 +11,4 @@ FEATURES_PROVIDED += periph_uart
 FEATURES_PROVIDED += periph_usbdev
 
 # pyboard provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/pyboard/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/pyboard/clock.config
diff --git a/boards/ruuvitag/Makefile.features b/boards/ruuvitag/Makefile.features
index fc952501e3..5b18c93a3d 100644
--- a/boards/ruuvitag/Makefile.features
+++ b/boards/ruuvitag/Makefile.features
@@ -8,7 +8,7 @@ FEATURES_PROVIDED += vdd_lc_filter_reg1
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/ruuvitag.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/ruuvitag.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/stm32f723e-disco/Makefile.features b/boards/stm32f723e-disco/Makefile.features
index d6669b2005..4454233875 100644
--- a/boards/stm32f723e-disco/Makefile.features
+++ b/boards/stm32f723e-disco/Makefile.features
@@ -12,4 +12,4 @@ FEATURES_PROVIDED += periph_uart
 FEATURES_PROVIDED += periph_usbdev
 
 # stm32f723e-disco provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/stm32f723e-disco/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/stm32f723e-disco/clock.config
diff --git a/boards/stm32f746g-disco/Makefile.features b/boards/stm32f746g-disco/Makefile.features
index 7e95717f28..431f2899c4 100644
--- a/boards/stm32f746g-disco/Makefile.features
+++ b/boards/stm32f746g-disco/Makefile.features
@@ -13,4 +13,4 @@ FEATURES_PROVIDED += periph_uart
 FEATURES_PROVIDED += periph_usbdev
 
 # stm32f746g-disco provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/stm32f746g-disco/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/stm32f746g-disco/clock.config
diff --git a/boards/stm32f769i-disco/Makefile.features b/boards/stm32f769i-disco/Makefile.features
index faeeabcf38..7a8128e5aa 100644
--- a/boards/stm32f769i-disco/Makefile.features
+++ b/boards/stm32f769i-disco/Makefile.features
@@ -9,4 +9,4 @@ FEATURES_PROVIDED += periph_uart
 FEATURES_PROVIDED += periph_usbdev
 
 # stm32f769i-disco provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/stm32f769i-disco/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/stm32f769i-disco/clock.config
diff --git a/boards/thingy52/Makefile.features b/boards/thingy52/Makefile.features
index eb7d17ed44..0ec83cf861 100644
--- a/boards/thingy52/Makefile.features
+++ b/boards/thingy52/Makefile.features
@@ -8,7 +8,7 @@ FEATURES_PROVIDED += vdd_lc_filter_reg1
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/thingy52.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/thingy52.config
 endif
 
 include $(RIOTBOARD)/common/nrf52/Makefile.features
diff --git a/boards/ublox-c030-u201/Makefile.features b/boards/ublox-c030-u201/Makefile.features
index c1313313a3..26fa7084ed 100644
--- a/boards/ublox-c030-u201/Makefile.features
+++ b/boards/ublox-c030-u201/Makefile.features
@@ -11,4 +11,4 @@ FEATURES_PROVIDED += periph_timer
 FEATURES_PROVIDED += periph_uart
 
 # ublox-c030-u201 provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/ublox-c030-u201/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/ublox-c030-u201/clock.config
diff --git a/boards/weact-f401cc/Makefile.features b/boards/weact-f401cc/Makefile.features
index bdf5a6e2bb..fa1a35efbf 100644
--- a/boards/weact-f401cc/Makefile.features
+++ b/boards/weact-f401cc/Makefile.features
@@ -3,4 +3,4 @@ CPU_MODEL = stm32f401cc
 include $(RIOTBOARD)/common/weact-f4x1cx/Makefile.features
 
 # weact-f401cc provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/weact-f401cc/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/weact-f401cc/clock.config
diff --git a/boards/weact-f401ce/Makefile.features b/boards/weact-f401ce/Makefile.features
index edb1d08a28..6921886adc 100644
--- a/boards/weact-f401ce/Makefile.features
+++ b/boards/weact-f401ce/Makefile.features
@@ -3,4 +3,4 @@ CPU_MODEL = stm32f401ce
 include $(RIOTBOARD)/common/weact-f4x1cx/Makefile.features
 
 # weact-f401ce provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/weact-f401ce/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/weact-f401ce/clock.config
diff --git a/boards/weact-f411ce/Makefile.features b/boards/weact-f411ce/Makefile.features
index d457ce74bf..8f3a504e16 100644
--- a/boards/weact-f411ce/Makefile.features
+++ b/boards/weact-f411ce/Makefile.features
@@ -3,4 +3,4 @@ CPU_MODEL = stm32f411ce
 include $(RIOTBOARD)/common/weact-f4x1cx/Makefile.features
 
 # weact-f411ce provides a custom default Kconfig clock configuration
-KCONFIG_ADD_CONFIG += $(RIOTBOARD)/weact-f411ce/clock.config
+KCONFIG_BOARD_CONFIG += $(RIOTBOARD)/weact-f411ce/clock.config
diff --git a/boards/yarm/Makefile.features b/boards/yarm/Makefile.features
index f0b8d87a80..cefe1dd6b3 100644
--- a/boards/yarm/Makefile.features
+++ b/boards/yarm/Makefile.features
@@ -18,5 +18,5 @@ FEATURES_PROVIDED += riotboot
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(BOARDDIR)/yarm.config
+  KCONFIG_BOARD_CONFIG += $(BOARDDIR)/yarm.config
 endif
diff --git a/cpu/atxmega/Makefile.features b/cpu/atxmega/Makefile.features
index 975be19ed6..7908685a4f 100644
--- a/cpu/atxmega/Makefile.features
+++ b/cpu/atxmega/Makefile.features
@@ -17,5 +17,5 @@ FEATURES_PROVIDED += periph_timer periph_timer_periodic
 # Add atxmega configurations. This configuration enables modules that are only available when
 # using Kconfig module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/atxmega/atxmega.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/atxmega/atxmega.config
 endif
diff --git a/cpu/cc2538/Makefile.features b/cpu/cc2538/Makefile.features
index 27bd934a5f..a25dc67994 100644
--- a/cpu/cc2538/Makefile.features
+++ b/cpu/cc2538/Makefile.features
@@ -19,5 +19,5 @@ include $(RIOTCPU)/cortexm_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/cc2538/cc2538.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/cc2538/cc2538.config
 endif
diff --git a/cpu/cortexm_common/Makefile.features b/cpu/cortexm_common/Makefile.features
index 5c1e56f60f..aa667450f6 100644
--- a/cpu/cortexm_common/Makefile.features
+++ b/cpu/cortexm_common/Makefile.features
@@ -43,5 +43,5 @@ FEATURES_PROVIDED += no_idle_thread
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/cortexm_common/cortexm_common.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/cortexm_common/cortexm_common.config
 endif
diff --git a/cpu/efm32/Makefile.features b/cpu/efm32/Makefile.features
index e7bd4ce41e..47e9bb76b0 100644
--- a/cpu/efm32/Makefile.features
+++ b/cpu/efm32/Makefile.features
@@ -38,5 +38,5 @@ include $(RIOTCPU)/cortexm_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1,$(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/efm32/efm32.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/efm32/efm32.config
 endif
diff --git a/cpu/kinetis/Makefile.features b/cpu/kinetis/Makefile.features
index c8735849a5..3a47100142 100644
--- a/cpu/kinetis/Makefile.features
+++ b/cpu/kinetis/Makefile.features
@@ -37,5 +37,5 @@ include $(RIOTCPU)/cortexm_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/kinetis/kinetis.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/kinetis/kinetis.config
 endif
diff --git a/cpu/lpc1768/Makefile.features b/cpu/lpc1768/Makefile.features
index 62c0d92de0..64de7f5367 100644
--- a/cpu/lpc1768/Makefile.features
+++ b/cpu/lpc1768/Makefile.features
@@ -12,5 +12,5 @@ include $(RIOTCPU)/cortexm_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/lpc1768/lpc1768.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/lpc1768/lpc1768.config
 endif
diff --git a/cpu/lpc23xx/Makefile.features b/cpu/lpc23xx/Makefile.features
index db4d1b2df8..4c60626e51 100644
--- a/cpu/lpc23xx/Makefile.features
+++ b/cpu/lpc23xx/Makefile.features
@@ -11,5 +11,5 @@ include $(RIOTCPU)/arm7_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/lpc23xx/lpc23xx.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/lpc23xx/lpc23xx.config
 endif
diff --git a/cpu/native/Makefile.features b/cpu/native/Makefile.features
index e1e258db64..0e237bea44 100644
--- a/cpu/native/Makefile.features
+++ b/cpu/native/Makefile.features
@@ -32,5 +32,5 @@ endif
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/native/native.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/native/native.config
 endif
diff --git a/cpu/sam0_common/Makefile.features b/cpu/sam0_common/Makefile.features
index e541dc161b..666e37bc93 100644
--- a/cpu/sam0_common/Makefile.features
+++ b/cpu/sam0_common/Makefile.features
@@ -31,5 +31,5 @@ include $(RIOTCPU)/cortexm_common/Makefile.features
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/sam0_common/sam0_common.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/sam0_common/sam0_common.config
 endif
diff --git a/cpu/stm32/Makefile.features b/cpu/stm32/Makefile.features
index 262ecbd295..06a7e47285 100644
--- a/cpu/stm32/Makefile.features
+++ b/cpu/stm32/Makefile.features
@@ -58,11 +58,11 @@ ifneq (,$(filter $(CPU_MODEL),$(STM32_WITH_MPU)))
   FEATURES_PROVIDED += cortexm_mpu
 endif
 
-# Add stm32 configs after including cortexm_common so stm32 takes precendence
+include $(RIOTCPU)/cortexm_common/Makefile.features
+
+# Add stm32 configs after including cortexm_common so stm32 takes precedence
 # This configuration enables modules that are only available when using Kconfig
 # module modelling
 ifeq (1, $(TEST_KCONFIG))
-  KCONFIG_ADD_CONFIG += $(RIOTCPU)/stm32/stm32.config
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/stm32/stm32.config
 endif
-
-include $(RIOTCPU)/cortexm_common/Makefile.features
diff --git a/doc/doxygen/src/kconfig/kconfig.md b/doc/doxygen/src/kconfig/kconfig.md
index 3d8fb0b3d9..b030825e31 100644
--- a/doc/doxygen/src/kconfig/kconfig.md
+++ b/doc/doxygen/src/kconfig/kconfig.md
@@ -63,7 +63,10 @@ files. Two files will be sources of configuration during the generation of the
 final header file: `app.config` and `user.config`, which should be placed
 inside the application's folder. `app.config` sets default configuration
 values for the particular application, the user can override them by setting
-them in `user.config`.
+them in `user.config`. Additionally, further `.config` files can be added to
+the variable `KCONFIG_ADD_CONFIG`, which will be applied _after_ default CPU and
+board configurations, `app.config` and `user.config`. This means that they will
+have priority.
 
 Let's say that the `SOCK_UTIL_SCHEME_MAXLEN` symbol in `sock_util` module needs
 to be configured. The `user.config` file could look like:
@@ -458,6 +461,34 @@ config BOARD_SAMR21_XPRO
     select HAS_RIOTBOOT
 ```
 
+### Default configurations
+
+Boards, common board directories, CPUs and common CPU directories may need to
+override default configuration values. Visible configuration symbols are
+configurable by the user and show on the menuconfig interface. `.config` files
+are used to set their values. To allow multiple sources of `.config` files,
+there are two Makefile variables developers should use: `KCONFIG_CPU_CONFIG` for
+sources added by the CPU or common CPU directories, and `KCONFIG_BOARD_CONFIG`
+for sources added by the board or common board directories. This ensures the
+correct priority of the configurations.
+
+Currently the `Makefile.features` infrastructure is used to populate the
+configuration sources. As the order in which `.config` files are merged matters,
+configuration sources should be ordered from more generic to more specific.
+Because board's `Makefile.features` is included before CPU's `Makefile.features`
+it is important to utilize two different lists of configuration sources. For
+instance, if `cpu/cortexm_common` adds its configuration, `cpu/stm32` should add
+its configuration after it, and `boards/stm32f769i-disco` after it.
+
+```Makefile
+include $(RIOTCPU)/cortexm_common/Makefile.features
+
+# Add stm32 configs after including cortexm_common so stm32 takes precedence
+ifeq (1, $(TEST_KCONFIG))
+  KCONFIG_CPU_CONFIG += $(RIOTCPU)/stm32/stm32.config
+endif
+```
+
 ## Summary of reserved Kconfig prefixes
 The following symbol prefixes have been assigned particular semantics and are
 reserved for the cases described below:
diff --git a/makefiles/kconfig.mk b/makefiles/kconfig.mk
index b321f2795b..189d13c685 100644
--- a/makefiles/kconfig.mk
+++ b/makefiles/kconfig.mk
@@ -61,13 +61,17 @@ KCONFIG_OUT_DEP = $(KCONFIG_OUT_CONFIG).d
 # Add configurations to merge, in ascendent priority (i.e. a file overrides the
 # previous ones).
 #
-# KCONFIG_ADD_CONFIG holds a list of .config files that are merged for the
-# initial configuration. This allows to split configurations in common files
-# and share them among boards or cpus.
+# KCONFIG_CPU_CONFIG, KCONFIG_BOARD_CONFIG and KCONFIG_ADD_CONFIG hold a lists
+# of .config files that are merged for the initial configuration. This allows
+# to split configurations in common files and share them among boards or cpus.
+# Files are merged from more generic to more specific.
 # This file will contain application default configurations used for Kconfig Test
+MERGE_SOURCES += $(KCONFIG_CPU_CONFIG)
+MERGE_SOURCES += $(KCONFIG_BOARD_CONFIG)
 MERGE_SOURCES += $(KCONFIG_ADD_CONFIG)
 MERGE_SOURCES += $(wildcard $(KCONFIG_APP_CONFIG))
 MERGE_SOURCES += $(wildcard $(KCONFIG_USER_CONFIG))
+
 MERGE_SOURCES += $(KCONFIG_GENERATED_ENV_CONFIG)
 
 # Create directory to place generated files