diff --git a/targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF52/TARGET_MCU_NRF52840/device/CMakeLists.txt b/targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF52/TARGET_MCU_NRF52840/device/CMakeLists.txt
index 9dbd8e40a7..e81255dea2 100644
--- a/targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF52/TARGET_MCU_NRF52840/device/CMakeLists.txt
+++ b/targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF52/TARGET_MCU_NRF52840/device/CMakeLists.txt
@@ -1,38 +1,27 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-function(_mbed_get_assembly_nrf52840_dk)
-    if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
-        set(STARTUP_FILE TOOLCHAIN_GCC_ARM/startup_NRF52840.S)
-    elseif(${MBED_TOOLCHAIN} STREQUAL "ARM")
-        set(STARTUP_FILE TOOLCHAIN_ARM_STD/startup_nrf52840.S)
-    elseif(${MBED_TOOLCHAIN} STREQUAL "IAR")
-        set(STARTUP_FILE TOOLCHAIN_IAR/startup_NRF52840_IAR.S)
-    endif()
-    target_sources(mbed-core INTERFACE ${STARTUP_FILE})
-endfunction()
+if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
+    set(STARTUP_FILE TOOLCHAIN_GCC_ARM/startup_NRF52840.S)
+    set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_GCC_ARM/NRF52840.ld)
+elseif(${MBED_TOOLCHAIN} STREQUAL "ARM")
+    set(STARTUP_FILE TOOLCHAIN_ARM_STD/startup_nrf52840.S)
+    set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_ARM_STD/nRF52840.sct)
+elseif(${MBED_TOOLCHAIN} STREQUAL "IAR")
+    set(STARTUP_FILE TOOLCHAIN_IAR/startup_NRF52840_IAR.S)
+    set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_IAR/nRF52840.icf)
+endif()
 
-function(_mbed_set_linker_file)
-    if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
-        set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_GCC_ARM/NRF52840.ld)
-    elseif(${MBED_TOOLCHAIN} STREQUAL "ARM")
-        set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_ARM_STD/nRF52840.sct)
-    elseif(${MBED_TOOLCHAIN} STREQUAL "IAR")
-        set(LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/TOOLCHAIN_IAR/nRF52840.icf)
-    endif()
-    set_property(GLOBAL PROPERTY MBED_TARGET_LINKER_FILE ${LINKER_FILE})
-endfunction()
-
-_mbed_get_assembly_nrf52840_dk()
-_mbed_set_linker_file()
+set_property(GLOBAL PROPERTY MBED_TARGET_LINKER_FILE ${LINKER_FILE})
 
 target_include_directories(mbed-core
     INTERFACE
-        ${CMAKE_CURRENT_SOURCE_DIR}
+        .
 )
 
 target_sources(mbed-core
     INTERFACE
+        ${STARTUP_FILE}
         cmsis_nvic.c
         system_nrf52840.c
 )