Rebase linker script change properly, re-add external toolchain file support

CMakeLists.txt

@@ -54,7 +54,6 @@ endif()
 
 mbed_set_cpu_core_definitions(mbed-core)
 if(${MBED_TOOLCHAIN_FILE_USED})
-    mbed_set_toolchain_options(mbed-core)
     mbed_set_profile_options(mbed-core ${MBED_TOOLCHAIN})
     mbed_set_c_lib(mbed-core ${MBED_C_LIB})
     mbed_set_printf_lib(mbed-core ${MBED_PRINTF_LIB})
@@ -134,7 +133,7 @@ function(mbed_set_mbed_target_linker_script target)
     if(MBED_TOOLCHAIN STREQUAL "GCC_ARM")
         set(CMAKE_PRE_BUILD_COMMAND
             COMMAND "arm-none-eabi-cpp" ${_linker_preprocess_definitions} -x assembler-with-cpp -E -Wp,-P
-                ${mbed_target_linker_script} -o ${CMAKE_BINARY_DIR}/${APP_NAME}.link_script.ld
+                ${mbed_target_linker_script} -o ${CMAKE_BINARY_DIR}/${target}.link_script.ld
 
             WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
             BYPRODUCTS "${CMAKE_BINARY_DIR}/${target}.link_script.ld"

tools/cmake/app.cmake

@@ -10,8 +10,10 @@ endif()
 include(${MBED_CONFIG_PATH}/mbed_config.cmake)
 
 # Load toolchain file
-set(MBED_TOOLCHAIN_FILE_USED TRUE CACHE INTERNAL "")
-include(${MBED_PATH}/tools/cmake/toolchain.cmake)
+if(NOT CMAKE_TOOLCHAIN_FILE OR MBED_TOOLCHAIN_FILE_USED)
+    set(MBED_TOOLCHAIN_FILE_USED TRUE CACHE INTERNAL "")
+    include(${MBED_PATH}/tools/cmake/toolchain.cmake)
+endif()
 
 # Specify available build profiles and add options for the selected build profile
 include(${MBED_PATH}/tools/cmake/profile.cmake)

tools/cmake/toolchains/ARM.cmake

@@ -37,13 +37,11 @@ list(APPEND link_options
 
 # Add linking time preprocessor macro for TFM targets
 if(MBED_CPU_CORE MATCHES "-NS$")
-        )
+    list(APPEND link_options
+        "--predefine=\"-DDOMAIN_NS=0x1\""
+    )
 endif()
 
-function(mbed_set_toolchain_options target)
-    # blank for ARMClang
-endfunction()
-
 # Configure the toolchain to select the selected C library
 function(mbed_set_c_lib target lib_type)
     if (${lib_type} STREQUAL "small")

tools/cmake/toolchains/GCC_ARM.cmake

@@ -7,11 +7,6 @@ set(CMAKE_CXX_COMPILER "arm-none-eabi-g++")
 set(GCC_ELF2BIN "arm-none-eabi-objcopy")
 set_property(GLOBAL PROPERTY ELF2BIN ${GCC_ELF2BIN})
 
-# Sets toolchain options for a target
-function(mbed_set_toolchain_options target)
-
-endfunction(mbed_set_toolchain_options)
-
 # build toolchain flags that get passed to everything (including CMake compiler checks)
 list(APPEND link_options
     "-Wl,--start-group"