diff --git a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_ARM/CMakeLists.txt b/cmsis/CMSIS_5/CMSIS/CMakeLists.txt
similarity index 84%
rename from rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_ARM/CMakeLists.txt
rename to cmsis/CMSIS_5/CMSIS/CMakeLists.txt
index f403f3ac48..50fa0ff0a3 100644
--- a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_ARM/CMakeLists.txt
+++ b/cmsis/CMSIS_5/CMSIS/CMakeLists.txt
@@ -2,3 +2,5 @@
 # SPDX-License-Identifier: Apache-2.0
 
 mbed_add_cmake_directory_if_labels("TARGET")
+
+add_subdirectory(RTOS2)
diff --git a/rtos/source/TARGET_CORTEX/rtx5/CMakeLists.txt b/cmsis/CMSIS_5/CMSIS/RTOS2/CMakeLists.txt
similarity index 100%
rename from rtos/source/TARGET_CORTEX/rtx5/CMakeLists.txt
rename to cmsis/CMSIS_5/CMSIS/RTOS2/CMakeLists.txt
diff --git a/rtos/source/TARGET_CORTEX/rtx5/RTX/CMakeLists.txt b/cmsis/CMSIS_5/CMSIS/RTOS2/RTX/CMakeLists.txt
similarity index 83%
rename from rtos/source/TARGET_CORTEX/rtx5/RTX/CMakeLists.txt
rename to cmsis/CMSIS_5/CMSIS/RTOS2/RTX/CMakeLists.txt
index b88041d6cb..2d2ce9457c 100644
--- a/rtos/source/TARGET_CORTEX/rtx5/RTX/CMakeLists.txt
+++ b/cmsis/CMSIS_5/CMSIS/RTOS2/RTX/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-function(_mbed_get_rtx_assembly toolchain_dir)
+function(_mbed_get_cortex_m_exception_handlers toolchain_dir)
     foreach(key ${MBED_TARGET_LABELS})
         if(${key} STREQUAL CORTEX_A)
             set(STARTUP_RTX_FILE TARGET_CORTEX_A/irq_ca.S)
@@ -26,7 +26,7 @@ function(_mbed_get_rtx_assembly toolchain_dir)
     endforeach()
 endfunction()
 
-function(_mbed_add_cortexa_handler_if)
+function(_mbed_get_cortex_a_exception_handlers)
     foreach(key ${MBED_TARGET_LABELS})
         if(${key} STREQUAL CORTEX_A)
             target_sources(mbed-os PRIVATE Config/TARGET_CORTEX_A/handlers.c)
@@ -34,21 +34,21 @@ function(_mbed_add_cortexa_handler_if)
     endforeach()
 endfunction()
 
-# Add Cortex A handlers if needed
-_mbed_add_cortexa_handler_if()
+_mbed_get_cortex_a_exception_handlers()
 
 if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
-    _mbed_get_rtx_assembly(TOOLCHAIN_GCC)
+    _mbed_get_cortex_m_exception_handlers(TOOLCHAIN_GCC)
 elseif(${MBED_TOOLCHAIN} STREQUAL "ARM")
-    _mbed_get_rtx_assembly(TOOLCHAIN_ARM)
+    _mbed_get_cortex_m_exception_handlers(TOOLCHAIN_ARM)
 elseif(${MBED_TOOLCHAIN} STREQUAL "IAR")
-    _mbed_get_rtx_assembly(TOOLCHAIN_IAR)
+    _mbed_get_cortex_m_exception_handlers(TOOLCHAIN_IAR)
 endif()
 
 target_include_directories(mbed-os
     PUBLIC
         Config
         Include
+        Include1
         Source
 )
 
@@ -56,6 +56,8 @@ target_sources(mbed-os
     PRIVATE
         Config/RTX_Config.c
 
+        Library/cmsis_os1.c
+
         Source/rtx_delay.c
         Source/rtx_evflags.c
         Source/rtx_evr.c
diff --git a/cmsis/TARGET_CORTEX_M/CMakeLists.txt b/cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_A/CMakeLists.txt
similarity index 74%
rename from cmsis/TARGET_CORTEX_M/CMakeLists.txt
rename to cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_A/CMakeLists.txt
index c244a5cb11..c740a29008 100644
--- a/cmsis/TARGET_CORTEX_M/CMakeLists.txt
+++ b/cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_A/CMakeLists.txt
@@ -1,12 +1,12 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-target_sources(mbed-os
-    PRIVATE
-        mbed_tz_context.c
-)
-
 target_include_directories(mbed-os
     PUBLIC
-        ${CMAKE_CURRENT_SOURCE_DIR}
+        Include
+)
+
+target_sources(mbed-os
+    PRIVATE
+        Source/irq_ctrl_gic.c
 )
diff --git a/cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_M/CMakeLists.txt b/cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_M/CMakeLists.txt
new file mode 100644
index 0000000000..281fe7731b
--- /dev/null
+++ b/cmsis/CMSIS_5/CMSIS/TARGET_CORTEX_M/CMakeLists.txt
@@ -0,0 +1,12 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+target_include_directories(mbed-os
+    PUBLIC
+        Include
+)
+
+target_sources(mbed-os
+    PRIVATE
+        Source/mbed_tz_context.c
+)
diff --git a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_GCC/CMakeLists.txt b/cmsis/CMSIS_5/CMakeLists.txt
similarity index 67%
rename from rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_GCC/CMakeLists.txt
rename to cmsis/CMSIS_5/CMakeLists.txt
index f403f3ac48..47b2183f3f 100644
--- a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_GCC/CMakeLists.txt
+++ b/cmsis/CMSIS_5/CMakeLists.txt
@@ -1,4 +1,4 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-mbed_add_cmake_directory_if_labels("TARGET")
+add_subdirectory(CMSIS)
diff --git a/cmsis/CMakeLists.txt b/cmsis/CMakeLists.txt
index 3f868a9d99..026ae16635 100644
--- a/cmsis/CMakeLists.txt
+++ b/cmsis/CMakeLists.txt
@@ -1,13 +1,5 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-mbed_add_cmake_directory_if_labels("TARGET")
-
-target_sources(mbed-os
-    PRIVATE
-        RTE_Components.h
-)
-
-target_include_directories(mbed-os
-    PUBLIC
-        ${CMAKE_CURRENT_SOURCE_DIR}
-)
+add_subdirectory(CMSIS_5)
+add_subdirectory(device)
diff --git a/cmsis/TARGET_CORTEX_A/CMakeLists.txt b/cmsis/TARGET_CORTEX_A/CMakeLists.txt
deleted file mode 100644
index 29121cd588..0000000000
--- a/cmsis/TARGET_CORTEX_A/CMakeLists.txt
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright (c) 2020 ARM Limited. All rights reserved.
-# SPDX-License-Identifier: Apache-2.0
-
-target_sources(mbed-os
-    PRIVATE
-        irq_ctrl_gic.c
-)
-
-if(${MBED_TOOLCHAIN} STREQUAL "IAR")
-    target_sources(mbed-os
-        PRIVATE
-            TOOLCHAIN_IAR/cmain.S
-    )
-endif()
-
-target_include_directories(mbed-os
-    PUBLIC
-        ${CMAKE_CURRENT_SOURCE_DIR}
-)
diff --git a/cmsis/device/CMakeLists.txt b/cmsis/device/CMakeLists.txt
new file mode 100644
index 0000000000..22811df2f7
--- /dev/null
+++ b/cmsis/device/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+add_subdirectory(RTE)
+add_subdirectory(rtos)
+
+target_include_directories(mbed-os
+    PUBLIC
+        .
+)
diff --git a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_IAR/CMakeLists.txt b/cmsis/device/RTE/CMakeLists.txt
similarity index 59%
rename from rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_IAR/CMakeLists.txt
rename to cmsis/device/RTE/CMakeLists.txt
index f403f3ac48..0e955b22d6 100644
--- a/rtos/source/TARGET_CORTEX/rtx5/RTX/Source/TOOLCHAIN_IAR/CMakeLists.txt
+++ b/cmsis/device/RTE/CMakeLists.txt
@@ -1,4 +1,7 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-mbed_add_cmake_directory_if_labels("TARGET")
+target_include_directories(mbed-os
+    PUBLIC
+        include
+)
diff --git a/rtos/source/TARGET_CORTEX/CMakeLists.txt b/cmsis/device/rtos/CMakeLists.txt
similarity index 79%
rename from rtos/source/TARGET_CORTEX/CMakeLists.txt
rename to cmsis/device/rtos/CMakeLists.txt
index 2d08035a66..3ade863e58 100644
--- a/rtos/source/TARGET_CORTEX/CMakeLists.txt
+++ b/cmsis/device/rtos/CMakeLists.txt
@@ -1,15 +1,6 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-target_sources(mbed-os PRIVATE
-    mbed_boot.c
-    mbed_rtos_rtx.c
-    mbed_rtx_handlers.c
-    mbed_rtx_idle.cpp
-)
-
-add_subdirectory(rtx5)
-
 if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
     target_sources(mbed-os
         PRIVATE
@@ -29,6 +20,12 @@ endif()
 
 target_include_directories(mbed-os
     PUBLIC
-        ${CMAKE_CURRENT_SOURCE_DIR}
-        rtx4
+        include
+)
+
+target_sources(mbed-os PRIVATE
+    source/mbed_boot.c
+    source/mbed_rtos_rtx.c
+    source/mbed_rtx_handlers.c
+    source/mbed_rtx_idle.cpp
 )
diff --git a/platform/source/TARGET_CORTEX_A/CMakeLists.txt b/platform/source/TARGET_CORTEX_A/CMakeLists.txt
new file mode 100644
index 0000000000..eede703de3
--- /dev/null
+++ b/platform/source/TARGET_CORTEX_A/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+function(_mbed_get_system_init)
+    if(${MBED_TOOLCHAIN} STREQUAL "IAR")
+        target_sources(mbed-os PRIVATE TOOLCHAIN_IAR/cmain.S)
+    endif()
+endfunction()
+
+_mbed_get_system_init()
diff --git a/rtos/CMakeLists.txt b/rtos/CMakeLists.txt
index 29b8692d11..01696a4350 100644
--- a/rtos/CMakeLists.txt
+++ b/rtos/CMakeLists.txt
@@ -1,8 +1,6 @@
 # Copyright (c) 2020 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-add_subdirectory(source/TARGET_CORTEX)
-
 target_include_directories(mbed-os
     PUBLIC
         ${CMAKE_CURRENT_SOURCE_DIR}