diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6a9a5d3f6..2e7ae4a08 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -170,6 +170,9 @@ elseif(OT_PLATFORM STREQUAL "external")
 elseif(OT_PLATFORM MATCHES "^nrf*")
     target_include_directories(ot-config INTERFACE ${PROJECT_SOURCE_DIR}/examples/platforms/nrf528xx/${OT_PLATFORM})
     add_subdirectory("${PROJECT_SOURCE_DIR}/examples/platforms/nrf528xx")
+elseif(OT_PLATFORM MATCHES "^efr*")
+    target_include_directories(ot-config INTERFACE ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/${OT_PLATFORM})
+    add_subdirectory("${PROJECT_SOURCE_DIR}/examples/platforms/efr32")
 else()
     target_include_directories(ot-config INTERFACE ${PROJECT_SOURCE_DIR}/examples/platforms/${OT_PLATFORM})
     add_subdirectory("${PROJECT_SOURCE_DIR}/examples/platforms/${OT_PLATFORM}")
diff --git a/etc/cmake/functions.cmake b/etc/cmake/functions.cmake
index 7c5e62a68..f2ceff880 100755
--- a/etc/cmake/functions.cmake
+++ b/etc/cmake/functions.cmake
@@ -31,10 +31,12 @@ function(ot_get_platforms arg_platforms)
     list(APPEND result "NO" "posix" "external")
     set(platforms_dir "${PROJECT_SOURCE_DIR}/examples/platforms")
     file(GLOB platforms RELATIVE "${platforms_dir}" "${platforms_dir}/*"
-            RELATIVE "${platforms_dir}/nrf528xx" "${platforms_dir}/nrf528xx/nrf*")
+            RELATIVE "${platforms_dir}/nrf528xx" "${platforms_dir}/nrf528xx/nrf*"
+            RELATIVE "${platforms_dir}/efr32" "${platforms_dir}/efr32/efr32*")
     foreach(platform IN LISTS platforms)
         if((IS_DIRECTORY "${platforms_dir}/${platform}") OR
-            (IS_DIRECTORY "${platforms_dir}/nrf528xx/${platform}"))
+            (IS_DIRECTORY "${platforms_dir}/nrf528xx/${platform}") OR
+            (IS_DIRECTORY "${platforms_dir}/efr32/${platform}"))
             list(APPEND result "${platform}")
         endif()
     endforeach()
diff --git a/examples/Makefile-efr32mg1 b/examples/Makefile-efr32mg1
index 705afe3ba..0bb070362 100644
--- a/examples/Makefile-efr32mg1
+++ b/examples/Makefile-efr32mg1
@@ -79,7 +79,6 @@ EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suit
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_alt/include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/config
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc
-EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc/configs
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_psa_driver/inc
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/CMSIS/Include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/Device/SiliconLabs/EFR32MG1P/Include
diff --git a/examples/Makefile-efr32mg12 b/examples/Makefile-efr32mg12
index 16461a2e9..74fee9734 100644
--- a/examples/Makefile-efr32mg12
+++ b/examples/Makefile-efr32mg12
@@ -97,7 +97,6 @@ EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suit
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_alt/include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/config
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc
-EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc/configs
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_psa_driver/inc
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/CMSIS/Include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/Device/SiliconLabs/EFR32MG12P/Include
diff --git a/examples/Makefile-efr32mg13 b/examples/Makefile-efr32mg13
index 5cbcc93a4..59b9ec23c 100644
--- a/examples/Makefile-efr32mg13
+++ b/examples/Makefile-efr32mg13
@@ -83,7 +83,6 @@ EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suit
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_alt/include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/config
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc
-EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc/configs
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_psa_driver/inc
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/CMSIS/Include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/Device/SiliconLabs/EFR32MG13P/Include
diff --git a/examples/Makefile-efr32mg21 b/examples/Makefile-efr32mg21
index 80db2a686..d003e33ec 100644
--- a/examples/Makefile-efr32mg21
+++ b/examples/Makefile-efr32mg21
@@ -89,7 +89,6 @@ EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suit
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_alt/include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/config
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc
-EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_mbedtls_support/inc/configs
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/util/third_party/crypto/sl_component/sl_psa_driver/inc
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/CMSIS/Include
 EFR32_MBEDTLS_CPPFLAGS += -I$(AbsTopSourceDir)/third_party/silabs/gecko_sdk_suite/v3.1/platform/Device/SiliconLabs/EFR32MG21/Include
diff --git a/examples/platforms/efr32/CMakeLists.txt b/examples/platforms/efr32/CMakeLists.txt
new file mode 100644
index 000000000..00bee251e
--- /dev/null
+++ b/examples/platforms/efr32/CMakeLists.txt
@@ -0,0 +1,143 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/utility.cmake)
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/includes.cmake)
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/imported_libs.cmake)
+
+
+# ==============================================================================
+# Common sources and includes
+# ==============================================================================
+set(EFR32_COMMON_SOURCES
+    src/alarm.c
+    src/diag.c
+    src/entropy.c
+    src/fem-control.c
+    src/flash.c
+    src/ieee802154mac.h
+    src/logging.c
+    src/mbedtls_config.h
+    src/memory.c
+    src/misc.c
+    src/openthread-core-efr32-config-check.h
+    src/openthread-core-efr32-config.h
+    src/platform-band.h
+    src/platform-efr32.h
+    src/radio.c
+    src/rail_config.h
+    src/startup-gcc.c
+    src/system.c
+    src/uart.c
+)
+
+set(EFR32_INCLUDES
+    ${CMAKE_CURRENT_SOURCE_DIR}/src
+    ${CMAKE_CURRENT_SOURCE_DIR}/${EFR32_PLATFORM}/crypto
+    ${CMAKE_CURRENT_SOURCE_DIR}/${EFR32_PLATFORM}/${BOARD_LOWERCASE}
+    ${PROJECT_SOURCE_DIR}/third_party/silabs/rail_config
+    ${SILABS_GSDK_INCLUDES}
+    ${PROJECT_SOURCE_DIR}/examples/platforms
+    ${PROJECT_SOURCE_DIR}/src/core
+)
+
+set(EFR32_CFLAGS
+    -Wno-sign-compare
+    -Wno-unused-parameter
+    -Wno-missing-field-initializers
+)
+
+# ==============================================================================
+# mbedtls
+# ==============================================================================
+if(NOT OT_EXTERNAL_MBEDTLS)
+    message(FATAL_ERROR "OT_EXTERNAL_MBEDTLS is not set. Please include the define when running cmake\n\t-DOT_EXTERNAL_MBEDTLS=silabs-mbedtls")
+else()
+    list(APPEND OT_PLATFORM_DEFINES "MBEDTLS_CONFIG_FILE=\"mbedtls_config.h\"")
+endif()
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+if(PLATFORM_LOWERCASE MATCHES "^efr32mg2\\d*")
+    list(APPEND OT_PUBLIC_INCLUDES
+        "${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/inc"
+        "${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src"
+    )
+    set(OT_PUBLIC_INCLUDES ${OT_PUBLIC_INCLUDES} PARENT_SCOPE)
+endif()
+
+# ==============================================================================
+# General variables
+# ==============================================================================
+
+# ==============================================================================
+# Filter out CFLAGS
+# ==============================================================================
+set(ignored_flags
+    "-pedantic-errors"  # Needed for RAIL lib
+    "-Wshadow"          # Needed for RAIL lib
+)
+
+foreach(flag IN LISTS ignored_flags)
+    string(REPLACE "${flag}" "" OT_CFLAGS "${OT_CFLAGS}")
+endforeach()
+list(APPEND EFR32_CFLAGS ${OT_CFLAGS})
+set(OT_CFLAGS ${OT_CFLAGS} PARENT_SCOPE)
+
+# Use default config file if one isn't specified
+if(NOT OT_CONFIG)
+    set(OT_CONFIG "${CMAKE_CURRENT_SOURCE_DIR}/src/openthread-core-efr32-config.h")
+    set(OT_CONFIG ${OT_CONFIG} PARENT_SCOPE)
+endif()
+
+list(APPEND OT_PLATFORM_DEFINES
+    "OPENTHREAD_PROJECT_CORE_CONFIG_FILE=\"${OT_CONFIG}\""
+    "OPENTHREAD_CORE_CONFIG_PLATFORM_CHECK_FILE=\"openthread-core-efr32-config-check.h\""
+)
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+# ==============================================================================
+# Platform targets
+# ==============================================================================
+set(EFR32_COMMON_3RD_LIBS
+    jlinkrtt
+    ${OT_MBEDTLS}
+)
+
+include(${PLATFORM_LOWERCASE}/${PLATFORM_LOWERCASE}.cmake)
+
+list(APPEND OT_PUBLIC_INCLUDES ${EFR32_INCLUDES})
+set(OT_PUBLIC_INCLUDES ${OT_PUBLIC_INCLUDES} PARENT_SCOPE)
+
+# ==============================================================================
+# sleepy-demo
+# ==============================================================================
+option(EFR32_APP_SLEEPY_DEMO "enable sleepy-demo app" ON)
+
+if(EFR32_APP_SLEEPY_DEMO)
+    add_subdirectory(sleepy-demo)
+endif()
diff --git a/examples/platforms/efr32/arm-none-eabi.cmake b/examples/platforms/efr32/arm-none-eabi.cmake
new file mode 100644
index 000000000..9f2e385f9
--- /dev/null
+++ b/examples/platforms/efr32/arm-none-eabi.cmake
@@ -0,0 +1,51 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(CMAKE_SYSTEM_NAME              Generic)
+set(CMAKE_SYSTEM_PROCESSOR         ARM)
+
+set(CMAKE_C_COMPILER               arm-none-eabi-gcc)
+set(CMAKE_CXX_COMPILER             arm-none-eabi-g++)
+set(CMAKE_ASM_COMPILER             arm-none-eabi-as)
+set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE COMPILER_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=softfp -mthumb -fdata-sections -ffunction-sections")
+
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=c99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
+
+set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
+set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
+set(CMAKE_ASM_FLAGS_DEBUG          "-g")
+
+set(CMAKE_C_FLAGS_RELEASE          "-Os")
+set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
+set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/efr32/efr32_platform_defs.am b/examples/platforms/efr32/efr32_platform_defs.am
index 223a08b3b..f69d240c0 100644
--- a/examples/platforms/efr32/efr32_platform_defs.am
+++ b/examples/platforms/efr32/efr32_platform_defs.am
@@ -89,7 +89,6 @@ SILABS_GSDK_CPPFLAGS                                                          =
     -I$(SDK_SRC_DIR)/platform/emlib/inc                                         \
     -I$(SDK_SRC_DIR)/platform/halconfig/inc/hal-config                          \
     -I$(SDK_SRC_DIR)/platform/radio/rail_lib/chip/efr32                         \
-    -I$(SDK_SRC_DIR)/platform/radio/rail_lib/chip/efr32/rf/common/cortex        \
     -I$(SDK_SRC_DIR)/platform/radio/rail_lib/common                             \
     -I$(SDK_SRC_DIR)/platform/radio/rail_lib/hal                                \
     -I$(SDK_SRC_DIR)/platform/radio/rail_lib/hal/efr32                          \
diff --git a/examples/platforms/efr32/efr32mg1/Makefile.am b/examples/platforms/efr32/efr32mg1/Makefile.am
index 873a8843c..fdf9e1eb5 100644
--- a/examples/platforms/efr32/efr32mg1/Makefile.am
+++ b/examples/platforms/efr32/efr32mg1/Makefile.am
@@ -33,7 +33,6 @@ lib_LIBRARIES = libopenthread-efr32mg1.a
 
 libopenthread_efr32mg1_a_CPPFLAGS                                             = \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
     -I$(top_srcdir)/examples/platforms/efr32/$(PLATFORM_LOWERCASE)/$(BOARD_LOWERCASE) \
diff --git a/examples/platforms/efr32/efr32mg1/README.md b/examples/platforms/efr32/efr32mg1/README.md
index 153ed0f5d..2473f2c1e 100644
--- a/examples/platforms/efr32/efr32mg1/README.md
+++ b/examples/platforms/efr32/efr32mg1/README.md
@@ -66,7 +66,35 @@ $ cd <path-to-openthread>
 $ ./bootstrap
 ```
 
-For EFR32MG1™ Mighty Gecko Wireless Starter Kit:
+For EFR32MG1™ Mighty Gecko Wireless Starter Kit, this can be done using both the CMake and autotools build systems
+
+**CMake (preferred)**
+
+```bash
+$ ./script/cmake-build efr32mg1 -DBOARD=brd4151a
+...
+-- Configuring done
+-- Generating done
+-- Build files have been written to: <path-to-openthread>/build/efr32mg1
++ [[ -n ot-rcp ]]
++ ninja ot-rcp
+[160/160] Linking CXX executable examples/apps/ncp/ot-rcp
++ cd <path-to-openthread>
+```
+
+After a successful build, the `elf` files are found in `<path-to-openthread>/build/efr32mg1/examples`.
+
+```bash
+# For linux
+$ find build/efr32mg1/examples -type f -executable
+build/efr32mg1/examples/apps/ncp/ot-rcp
+
+# For BSD/Darwin/mac systems
+$ find build/efr32mg1/examples -type f -perm +111
+build/efr32mg1/examples/apps/ncp/ot-rcp
+```
+
+**autotools (soon to be depracated)**
 
 ```bash
 $ make -f examples/Makefile-efr32mg1 BOARD=BRD4151A
diff --git a/examples/platforms/efr32/efr32mg1/arm-none-eabi.cmake b/examples/platforms/efr32/efr32mg1/arm-none-eabi.cmake
new file mode 100644
index 000000000..9f2e385f9
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg1/arm-none-eabi.cmake
@@ -0,0 +1,51 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(CMAKE_SYSTEM_NAME              Generic)
+set(CMAKE_SYSTEM_PROCESSOR         ARM)
+
+set(CMAKE_C_COMPILER               arm-none-eabi-gcc)
+set(CMAKE_CXX_COMPILER             arm-none-eabi-g++)
+set(CMAKE_ASM_COMPILER             arm-none-eabi-as)
+set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE COMPILER_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=softfp -mthumb -fdata-sections -ffunction-sections")
+
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=c99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
+
+set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
+set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
+set(CMAKE_ASM_FLAGS_DEBUG          "-g")
+
+set(CMAKE_C_FLAGS_RELEASE          "-Os")
+set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
+set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/efr32/efr32mg1/efr32mg1.cmake b/examples/platforms/efr32/efr32mg1/efr32mg1.cmake
new file mode 100644
index 000000000..39e5da530
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg1/efr32mg1.cmake
@@ -0,0 +1,95 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Verify board is supported for platform
+# ==============================================================================
+if(BOARD_LOWERCASE STREQUAL "brd4151a")
+    set(MCU "EFR32MG1P232F256GM48")
+else()
+    message(FATAL_ERROR "
+    BOARD=${BOARD} not supported.
+
+    Please provide a value for BOARD variable e.g BOARD=brd4151a.
+    Currently supported:
+    - brd4151a
+    ")
+endif()
+
+list(APPEND OT_PLATFORM_DEFINES "${MCU}")
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+# ==============================================================================
+# Platform library
+# ==============================================================================
+set(OT_PLATFORM_LIB "openthread-efr32mg1")
+set(OT_PLATFORM_LIB ${OT_PLATFORM_LIB} PARENT_SCOPE)
+
+set(LD_FILE "${CMAKE_CURRENT_SOURCE_DIR}/efr32mg1/efr32mg1.ld")
+
+add_library(openthread-efr32mg1
+    ${EFR32_COMMON_SOURCES}
+    $<TARGET_OBJECTS:openthread-platform-utils>
+)
+
+set_target_properties(openthread-efr32mg1
+    PROPERTIES
+        C_STANDARD 99
+        CXX_STANDARD 11
+)
+
+target_link_libraries(openthread-efr32mg1
+    PUBLIC
+        ${EFR32_COMMON_3RD_LIBS}
+        silabs-libnvm3_CM4_gcc
+        silabs-efr32mg1-sdk
+        -T${LD_FILE}
+        -Wl,--gc-sections
+        -Wl,-Map=$<TARGET_PROPERTY:NAME>.map
+    PRIVATE
+        ot-config
+)
+
+target_compile_definitions(openthread-efr32mg1
+    PUBLIC
+        ${OT_PLATFORM_DEFINES}
+)
+
+target_compile_options(openthread-efr32mg1
+    PRIVATE
+        ${EFR32_CFLAGS}
+)
+
+target_include_directories(openthread-efr32mg1
+    PUBLIC
+        ${EFR32_INCLUDES}
+    PRIVATE
+        ${SILABS_EFR32MG1X_INCLUDES}
+        ${OT_PUBLIC_INCLUDES}
+)
+
diff --git a/examples/platforms/efr32/efr32mg12/Makefile.am b/examples/platforms/efr32/efr32mg12/Makefile.am
index 73cefb5a0..023523670 100644
--- a/examples/platforms/efr32/efr32mg12/Makefile.am
+++ b/examples/platforms/efr32/efr32mg12/Makefile.am
@@ -33,7 +33,6 @@ lib_LIBRARIES = libopenthread-efr32mg12.a
 
 libopenthread_efr32mg12_a_CPPFLAGS                                            = \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
     -I$(top_srcdir)/examples/platforms/efr32/$(PLATFORM_LOWERCASE)/$(BOARD_LOWERCASE) \
diff --git a/examples/platforms/efr32/efr32mg12/README.md b/examples/platforms/efr32/efr32mg12/README.md
index 7ee0592f1..713e0dcb2 100644
--- a/examples/platforms/efr32/efr32mg12/README.md
+++ b/examples/platforms/efr32/efr32mg12/README.md
@@ -71,7 +71,47 @@ $ cd <path-to-openthread>
 $ ./bootstrap
 ```
 
-For EFR32MG12™ Mighty Gecko Wireless Starter Kit:
+For EFR32MG12™ Mighty Gecko Wireless Starter Kit, this can be done using both the CMake and autotools build systems
+
+**CMake (preferred)**
+
+```bash
+$ ./script/cmake-build efr32mg12 -DBOARD=brd4161a
+...
+-- Configuring done
+-- Generating done
+-- Build files have been written to: <path-to-openthread>/build/efr32mg12
++ [[ -n ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd ]]
++ ninja ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd
+[572/572] Linking CXX executable examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
++ cd <path-to-openthread>
+```
+
+After a successful build, the `elf` files are found in `<path-to-openthread>/build/efr32mg12/examples`.
+
+```bash
+# For linux
+$ find build/efr32mg12/examples -type f -executable
+build/efr32mg12/examples/apps/cli/ot-cli-mtd
+build/efr32mg12/examples/apps/cli/ot-cli-ftd
+build/efr32mg12/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg12/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg12/examples/apps/ncp/ot-rcp
+build/efr32mg12/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg12/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+
+# For BSD/Darwin/mac systems
+$ find build/efr32mg12/examples -type f -perm +111
+build/efr32mg12/examples/apps/cli/ot-cli-mtd
+build/efr32mg12/examples/apps/cli/ot-cli-ftd
+build/efr32mg12/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg12/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg12/examples/apps/ncp/ot-rcp
+build/efr32mg12/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg12/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+```
+
+**autotools (soon to be depracated)**
 
 ```bash
 $ make -f examples/Makefile-efr32mg12 BOARD=BRD4161A
diff --git a/examples/platforms/efr32/efr32mg12/arm-none-eabi.cmake b/examples/platforms/efr32/efr32mg12/arm-none-eabi.cmake
new file mode 100644
index 000000000..9f2e385f9
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg12/arm-none-eabi.cmake
@@ -0,0 +1,51 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(CMAKE_SYSTEM_NAME              Generic)
+set(CMAKE_SYSTEM_PROCESSOR         ARM)
+
+set(CMAKE_C_COMPILER               arm-none-eabi-gcc)
+set(CMAKE_CXX_COMPILER             arm-none-eabi-g++)
+set(CMAKE_ASM_COMPILER             arm-none-eabi-as)
+set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE COMPILER_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=softfp -mthumb -fdata-sections -ffunction-sections")
+
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=c99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
+
+set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
+set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
+set(CMAKE_ASM_FLAGS_DEBUG          "-g")
+
+set(CMAKE_C_FLAGS_RELEASE          "-Os")
+set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
+set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/efr32/efr32mg12/efr32mg12.cmake b/examples/platforms/efr32/efr32mg12/efr32mg12.cmake
new file mode 100644
index 000000000..ad73e5f9a
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg12/efr32mg12.cmake
@@ -0,0 +1,104 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Verify board is supported for platform
+# ==============================================================================
+if(BOARD_LOWERCASE STREQUAL "brd4304a")
+    set(MCU "EFR32MG12P432F1024GM48")
+elseif(BOARD_LOWERCASE STREQUAL "brd4161a")
+    set(MCU "EFR32MG12P432F1024GL125")
+elseif(BOARD_LOWERCASE STREQUAL "brd4166a")
+    set(MCU "EFR32MG12P332F1024GL125")
+elseif(BOARD_LOWERCASE STREQUAL "brd4170a")
+    set(MCU "EFR32MG12P433F1024GM68")
+else()
+    message(FATAL_ERROR "
+    BOARD=${BOARD} not supported.
+
+    Please provide a value for BOARD variable e.g BOARD=brd4161a.
+    Currently supported:
+    - brd4161a
+    - brd4166a
+    - brd4170a
+    - brd4304a
+    ")
+endif()
+
+list(APPEND OT_PLATFORM_DEFINES "${MCU}")
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+# ==============================================================================
+# Platform library
+# ==============================================================================
+set(OT_PLATFORM_LIB "openthread-efr32mg12")
+set(OT_PLATFORM_LIB ${OT_PLATFORM_LIB} PARENT_SCOPE)
+
+set(LD_FILE "${CMAKE_CURRENT_SOURCE_DIR}/efr32mg12/efr32mg12.ld")
+
+add_library(openthread-efr32mg12
+    ${EFR32_COMMON_SOURCES}
+    $<TARGET_OBJECTS:openthread-platform-utils>
+)
+
+set_target_properties(openthread-efr32mg12
+    PROPERTIES
+        C_STANDARD 99
+        CXX_STANDARD 11
+)
+
+target_link_libraries(openthread-efr32mg12
+    PUBLIC
+        ${EFR32_COMMON_3RD_LIBS}
+        silabs-libnvm3_CM4_gcc
+        silabs-efr32mg12-sdk
+        -T${LD_FILE}
+        -Wl,--gc-sections
+        -Wl,-Map=$<TARGET_PROPERTY:NAME>.map
+    PRIVATE
+        ot-config
+)
+
+target_compile_definitions(openthread-efr32mg12
+    PUBLIC
+        ${OT_PLATFORM_DEFINES}
+)
+
+target_compile_options(openthread-efr32mg12
+    PRIVATE
+        ${EFR32_CFLAGS}
+)
+
+target_include_directories(openthread-efr32mg12
+    PUBLIC
+        ${EFR32_INCLUDES}
+    PRIVATE
+        ${SILABS_EFR32MG1X_INCLUDES}
+        ${OT_PUBLIC_INCLUDES}
+)
+
diff --git a/examples/platforms/efr32/efr32mg13/Makefile.am b/examples/platforms/efr32/efr32mg13/Makefile.am
index b50f02913..cea711d27 100644
--- a/examples/platforms/efr32/efr32mg13/Makefile.am
+++ b/examples/platforms/efr32/efr32mg13/Makefile.am
@@ -33,7 +33,6 @@ lib_LIBRARIES = libopenthread-efr32mg13.a
 
 libopenthread_efr32mg13_a_CPPFLAGS                                            = \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
     -I$(top_srcdir)/examples/platforms/efr32/$(PLATFORM_LOWERCASE)/$(BOARD_LOWERCASE) \
diff --git a/examples/platforms/efr32/efr32mg13/README.md b/examples/platforms/efr32/efr32mg13/README.md
index 7a6cd080d..98a8c3c3d 100644
--- a/examples/platforms/efr32/efr32mg13/README.md
+++ b/examples/platforms/efr32/efr32mg13/README.md
@@ -70,7 +70,47 @@ $ cd <path-to-openthread>
 $ ./bootstrap
 ```
 
-For EFR32MG13™ Mighty Gecko Wireless Starter Kit:
+For EFR32MG13™ Mighty Gecko Wireless Starter Kit, this can be done using both the CMake and autotools build systems
+
+**CMake (preferred)**
+
+```bash
+$ ./script/cmake-build efr32mg13 -DBOARD=brd4168a
+...
+-- Configuring done
+-- Generating done
+-- Build files have been written to: <path-to-openthread>/build/efr32mg13
++ [[ -n ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd ]]
++ ninja ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd
+[573/573] Linking CXX executable examples/apps/ncp/ot-ncp-ftd
++ cd <path-to-openthread>
+```
+
+After a successful build, the `elf` files are found in `<path-to-openthread>/build/efr32mg13/examples`.
+
+```bash
+# For linux
+$ find build/efr32mg13/examples -type f -executable
+build/efr32mg13/examples/apps/cli/ot-cli-mtd
+build/efr32mg13/examples/apps/cli/ot-cli-ftd
+build/efr32mg13/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg13/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg13/examples/apps/ncp/ot-rcp
+build/efr32mg13/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg13/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+
+# For BSD/Darwin/mac systems
+$ find build/efr32mg13/examples -type f -perm +111
+build/efr32mg13/examples/apps/cli/ot-cli-mtd
+build/efr32mg13/examples/apps/cli/ot-cli-ftd
+build/efr32mg13/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg13/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg13/examples/apps/ncp/ot-rcp
+build/efr32mg13/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg13/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+```
+
+**autotools (soon to be depracated)**
 
 ```bash
 $ make -f examples/Makefile-efr32mg13 BOARD=BRD4168A
diff --git a/examples/platforms/efr32/efr32mg13/arm-none-eabi.cmake b/examples/platforms/efr32/efr32mg13/arm-none-eabi.cmake
new file mode 100644
index 000000000..9f2e385f9
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg13/arm-none-eabi.cmake
@@ -0,0 +1,51 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(CMAKE_SYSTEM_NAME              Generic)
+set(CMAKE_SYSTEM_PROCESSOR         ARM)
+
+set(CMAKE_C_COMPILER               arm-none-eabi-gcc)
+set(CMAKE_CXX_COMPILER             arm-none-eabi-g++)
+set(CMAKE_ASM_COMPILER             arm-none-eabi-as)
+set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE COMPILER_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=softfp -mthumb -fdata-sections -ffunction-sections")
+
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=c99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
+
+set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
+set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
+set(CMAKE_ASM_FLAGS_DEBUG          "-g")
+
+set(CMAKE_C_FLAGS_RELEASE          "-Os")
+set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
+set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/efr32/efr32mg13/efr32mg13.cmake b/examples/platforms/efr32/efr32mg13/efr32mg13.cmake
new file mode 100644
index 000000000..c94490173
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg13/efr32mg13.cmake
@@ -0,0 +1,95 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Verify board is supported for platform
+# ==============================================================================
+if(BOARD_LOWERCASE STREQUAL "brd4168a")
+    set(MCU "EFR32MG13P732F512GM48")
+else()
+    message(FATAL_ERROR "
+    BOARD=${BOARD} not supported.
+
+    Please provide a value for BOARD variable e.g BOARD=brd4168a.
+    Currently supported:
+    - brd4168a
+    ")
+endif()
+
+list(APPEND OT_PLATFORM_DEFINES "${MCU}")
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+# ==============================================================================
+# Platform library
+# ==============================================================================
+set(OT_PLATFORM_LIB "openthread-efr32mg13")
+set(OT_PLATFORM_LIB ${OT_PLATFORM_LIB} PARENT_SCOPE)
+
+set(LD_FILE "${CMAKE_CURRENT_SOURCE_DIR}/efr32mg13/efr32mg13.ld")
+
+add_library(openthread-efr32mg13
+    ${EFR32_COMMON_SOURCES}
+    $<TARGET_OBJECTS:openthread-platform-utils>
+)
+
+set_target_properties(openthread-efr32mg13
+    PROPERTIES
+        C_STANDARD 99
+        CXX_STANDARD 11
+)
+
+target_link_libraries(openthread-efr32mg13
+    PUBLIC
+        ${EFR32_COMMON_3RD_LIBS}
+        silabs-libnvm3_CM4_gcc
+        silabs-efr32mg13-sdk
+        -T${LD_FILE}
+        -Wl,--gc-sections
+        -Wl,-Map=$<TARGET_PROPERTY:NAME>.map
+    PRIVATE
+        ot-config
+)
+
+target_compile_definitions(openthread-efr32mg13
+    PUBLIC
+        ${OT_PLATFORM_DEFINES}
+)
+
+target_compile_options(openthread-efr32mg13
+    PRIVATE
+        ${EFR32_CFLAGS}
+)
+
+target_include_directories(openthread-efr32mg13
+    PUBLIC
+        ${EFR32_INCLUDES}
+    PRIVATE
+        ${SILABS_EFR32MG1X_INCLUDES}
+        ${OT_PUBLIC_INCLUDES}
+)
+
diff --git a/examples/platforms/efr32/efr32mg21/Makefile.am b/examples/platforms/efr32/efr32mg21/Makefile.am
index 4697d3c2b..3ce9a376f 100644
--- a/examples/platforms/efr32/efr32mg21/Makefile.am
+++ b/examples/platforms/efr32/efr32mg21/Makefile.am
@@ -33,7 +33,6 @@ lib_LIBRARIES = libopenthread-efr32mg21.a
 
 libopenthread_efr32mg21_a_CPPFLAGS                                            = \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
     -I$(top_srcdir)/examples/platforms/efr32/$(PLATFORM_LOWERCASE)/$(BOARD_LOWERCASE) \
diff --git a/examples/platforms/efr32/efr32mg21/README.md b/examples/platforms/efr32/efr32mg21/README.md
index c2c64dcf8..610ca26cb 100644
--- a/examples/platforms/efr32/efr32mg21/README.md
+++ b/examples/platforms/efr32/efr32mg21/README.md
@@ -65,7 +65,47 @@ $ cd <path-to-openthread>
 $ ./bootstrap
 ```
 
-For EFR32MG21™ Mighty Gecko Wireless Starter Kit:
+For EFR32MG21™ Mighty Gecko Wireless Starter Kit, this can be done using both the CMake and autotools build systems
+
+**CMake (preferred)**
+
+```bash
+$ ./script/cmake-build efr32mg21 -DBOARD=brd4180b
+...
+-- Configuring done
+-- Generating done
+-- Build files have been written to: <path-to-openthread>/build/efr32mg21
++ [[ -n ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd ]]
++ ninja ot-rcp ot-cli-ftd ot-cli-mtd ot-ncp-ftd ot-ncp-mtd sleepy-demo-ftd sleepy-demo-mtd
+[940/940] Linking CXX executable examples/apps/ncp/ot-ncp-ftd
++ cd <path-to-openthread>
+```
+
+After a successful build, the `elf` files are found in `<path-to-openthread>/build/efr32mg21/examples`.
+
+```bash
+# For linux
+$ find build/efr32mg21/examples -type f -executable
+build/efr32mg21/examples/apps/cli/ot-cli-mtd
+build/efr32mg21/examples/apps/cli/ot-cli-ftd
+build/efr32mg21/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg21/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg21/examples/apps/ncp/ot-rcp
+build/efr32mg21/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg21/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+
+# For BSD/Darwin/mac systems
+$ find build/efr32mg21/examples -type f -perm +111
+build/efr32mg21/examples/apps/cli/ot-cli-mtd
+build/efr32mg21/examples/apps/cli/ot-cli-ftd
+build/efr32mg21/examples/apps/ncp/ot-ncp-ftd
+build/efr32mg21/examples/apps/ncp/ot-ncp-mtd
+build/efr32mg21/examples/apps/ncp/ot-rcp
+build/efr32mg21/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/sleepy-demo-ftd
+build/efr32mg21/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/sleepy-demo-mtd
+```
+
+**autotools (soon to be depracated)**
 
 ```bash
 $ make -f examples/Makefile-efr32mg21 BOARD=BRD4180A
diff --git a/examples/platforms/efr32/efr32mg21/arm-none-eabi.cmake b/examples/platforms/efr32/efr32mg21/arm-none-eabi.cmake
new file mode 100644
index 000000000..046031638
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg21/arm-none-eabi.cmake
@@ -0,0 +1,51 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(CMAKE_SYSTEM_NAME              Generic)
+set(CMAKE_SYSTEM_PROCESSOR         ARM)
+
+set(CMAKE_C_COMPILER               arm-none-eabi-gcc)
+set(CMAKE_CXX_COMPILER             arm-none-eabi-g++)
+set(CMAKE_ASM_COMPILER             arm-none-eabi-as)
+set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE COMPILER_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+set(COMMON_C_FLAGS                 "-mcpu=cortex-m33 -mthumb -fmessage-length=0 -ffunction-sections -fdata-sections -mfpu=fpv5-sp-d16 -mfloat-abi=hard")
+
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=c99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
+
+set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
+set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
+set(CMAKE_ASM_FLAGS_DEBUG          "-g")
+
+set(CMAKE_C_FLAGS_RELEASE          "-Os")
+set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
+set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/efr32/efr32mg21/efr32mg21.cmake b/examples/platforms/efr32/efr32mg21/efr32mg21.cmake
new file mode 100644
index 000000000..eaaffdd49
--- /dev/null
+++ b/examples/platforms/efr32/efr32mg21/efr32mg21.cmake
@@ -0,0 +1,98 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Verify board is supported for platform
+# ==============================================================================
+if(BOARD_LOWERCASE STREQUAL "brd4180a")
+    set(MCU "EFR32MG21A020F1024IM32")
+elseif(BOARD_LOWERCASE STREQUAL "brd4180b")
+    set(MCU "EFR32MG21A020F1024IM32")
+else()
+    message(FATAL_ERROR "
+    BOARD=${BOARD} not supported.
+
+    Please provide a value for BOARD variable e.g BOARD=brd4180a.
+    Currently supported:
+    - brd4180a
+    - brd4180b
+    ")
+endif()
+
+list(APPEND OT_PLATFORM_DEFINES "${MCU}")
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
+
+# ==============================================================================
+# Platform library
+# ==============================================================================
+set(OT_PLATFORM_LIB "openthread-efr32mg21")
+set(OT_PLATFORM_LIB ${OT_PLATFORM_LIB} PARENT_SCOPE)
+
+set(LD_FILE "${CMAKE_CURRENT_SOURCE_DIR}/efr32mg21/efr32mg21.ld")
+
+add_library(openthread-efr32mg21
+    ${EFR32_COMMON_SOURCES}
+    $<TARGET_OBJECTS:openthread-platform-utils>
+)
+
+set_target_properties(openthread-efr32mg21
+    PROPERTIES
+        C_STANDARD 99
+        CXX_STANDARD 11
+)
+
+target_link_libraries(openthread-efr32mg21
+    PUBLIC
+        ${EFR32_COMMON_3RD_LIBS}
+        silabs-libnvm3_CM33_gcc
+        silabs-efr32mg21-sdk
+        -T${LD_FILE}
+        -Wl,--gc-sections
+        -Wl,-Map=$<TARGET_PROPERTY:NAME>.map
+    PRIVATE
+        ot-config
+)
+
+target_compile_definitions(openthread-efr32mg21
+    PUBLIC
+        ${OT_PLATFORM_DEFINES}
+)
+
+target_compile_options(openthread-efr32mg21
+    PRIVATE
+        ${EFR32_CFLAGS}
+)
+
+target_include_directories(openthread-efr32mg21
+    PUBLIC
+        ${EFR32_INCLUDES}
+    PRIVATE
+        ${SILABS_EFR32MG2X_INCLUDES}
+        ${OT_PUBLIC_INCLUDES}
+)
+
diff --git a/examples/platforms/efr32/sleepy-demo/CMakeLists.txt b/examples/platforms/efr32/sleepy-demo/CMakeLists.txt
new file mode 100644
index 000000000..b99a6b6b9
--- /dev/null
+++ b/examples/platforms/efr32/sleepy-demo/CMakeLists.txt
@@ -0,0 +1,35 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+if(OT_FTD)
+    add_subdirectory(sleepy-demo-ftd)
+endif()
+
+if(OT_MTD)
+    add_subdirectory(sleepy-demo-mtd)
+endif()
diff --git a/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/CMakeLists.txt b/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/CMakeLists.txt
new file mode 100644
index 000000000..521f2e6f2
--- /dev/null
+++ b/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/CMakeLists.txt
@@ -0,0 +1,52 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+add_executable(sleepy-demo-ftd
+    main.c
+)
+
+target_include_directories(sleepy-demo-ftd PRIVATE ${COMMON_INCLUDES})
+
+target_link_libraries(sleepy-demo-ftd PRIVATE
+    openthread-cli-ftd
+    ${OT_PLATFORM_LIB}
+    openthread-ftd
+    ${OT_PLATFORM_LIB}
+    ${OT_MBEDTLS}
+    ot-config
+)
+
+
+target_compile_options(sleepy-demo-ftd
+    PRIVATE
+        ${EFR32_CFLAGS}
+)
+
+install(TARGETS sleepy-demo-ftd
+    DESTINATION bin)
+
diff --git a/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/Makefile.am b/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/Makefile.am
index 141968eae..eff74bf28 100644
--- a/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/Makefile.am
+++ b/examples/platforms/efr32/sleepy-demo/sleepy-demo-ftd/Makefile.am
@@ -36,7 +36,6 @@ bin_PROGRAMS                                                                  =
     $(NULL)
 
 CPPFLAGS_COMMON                                                              += \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
diff --git a/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/CMakeLists.txt b/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/CMakeLists.txt
new file mode 100644
index 000000000..8408e6f17
--- /dev/null
+++ b/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/CMakeLists.txt
@@ -0,0 +1,45 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+add_executable(sleepy-demo-mtd
+    main.c
+)
+
+target_include_directories(sleepy-demo-mtd PRIVATE ${COMMON_INCLUDES})
+
+target_link_libraries(sleepy-demo-mtd PRIVATE
+    openthread-cli-mtd
+    ${OT_PLATFORM_LIB}
+    openthread-mtd
+    ${OT_PLATFORM_LIB}
+    ${OT_MBEDTLS}
+    ot-config
+)
+
+install(TARGETS sleepy-demo-mtd
+    DESTINATION bin)
diff --git a/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/Makefile.am b/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/Makefile.am
index 6adedec40..64e9bb882 100644
--- a/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/Makefile.am
+++ b/examples/platforms/efr32/sleepy-demo/sleepy-demo-mtd/Makefile.am
@@ -36,7 +36,6 @@ bin_PROGRAMS                                                                  =
     $(NULL)
 
 CPPFLAGS_COMMON                                                              += \
-    -DNVIC_CONFIG=\"platform/base/hal/micro/cortexm3/efm32/nvic-config.h\"      \
     -DPLATFORM_HEADER=\"platform/base/hal/micro/cortexm3/compiler/gcc.h\"       \
     -Wno-sign-compare                                                           \
     -I$(top_srcdir)/examples/platforms                                          \
diff --git a/examples/platforms/efr32/src/alarm.c b/examples/platforms/efr32/src/alarm.c
index 842823f8c..81a001539 100644
--- a/examples/platforms/efr32/src/alarm.c
+++ b/examples/platforms/efr32/src/alarm.c
@@ -156,7 +156,7 @@ uint32_t otPlatAlarmMicroGetNow(void)
 void otPlatAlarmMicroStartAt(otInstance *aInstance, uint32_t aT0, uint32_t aDt)
 {
     // TODO microsecond support
-    return otPlatAlarmMilliStartAt(aInstance, aT0, aDt);
+    otPlatAlarmMilliStartAt(aInstance, aT0, aDt);
 }
 
 void otPlatAlarmMicroStop(otInstance *aInstance)
diff --git a/examples/platforms/efr32/src/openthread-core-efr32-config.h b/examples/platforms/efr32/src/openthread-core-efr32-config.h
index 49410853d..360821007 100644
--- a/examples/platforms/efr32/src/openthread-core-efr32-config.h
+++ b/examples/platforms/efr32/src/openthread-core-efr32-config.h
@@ -33,6 +33,9 @@
  */
 
 #include "board_config.h"
+
+// IMPORTANT: Do not remove this include. Apps will build without error, but
+// they will not boot up properly
 #include "em_msc.h"
 
 #ifndef OPENTHREAD_CORE_EFR32_CONFIG_H_
diff --git a/script/cmake-build b/script/cmake-build
index bd0f00bbe..4b5e7db2c 100755
--- a/script/cmake-build
+++ b/script/cmake-build
@@ -46,6 +46,17 @@
 #
 #      script/cmake-build ${platform} ${nrf_build_type} -D${option}=ON -D${option}=OFF
 #
+#  Need to add BOARD when compiling efr32:
+#
+#      script/cmake-build ${platform} -DBOARD=${EFR32 board}
+#
+#    Example:
+#      script/cmake-build efr32mg21 -DBOARD=brd4180b
+#
+#  To enable dynamic multiprotocol support on efr32:
+#
+#      script/cmake-build ${platform}  -DBOARD=${EFR32 board} -DDMP=ON
+#
 #  Compile with the specified ninja build target:
 #
 #      OT_CMAKE_NINJA_TARGET="ot-cli-ftd" script/cmake-build ${platform}
@@ -68,7 +79,7 @@ set -euxo pipefail
 OT_CMAKE_NINJA_TARGET=${OT_CMAKE_NINJA_TARGET:-}
 
 readonly OT_SRCDIR="$(pwd)"
-readonly OT_PLATFORMS=(cc1352 cc2538 cc2650 cc2652 kw41z nrf52811 nrf52833 nrf52840 gp712 qpg7015m qpg6095 qpg6100 samr21 simulation posix)
+readonly OT_PLATFORMS=(cc1352 cc2538 cc2650 cc2652 efr32mg1 efr32mg12 efr32mg13 efr32mg21 kw41z nrf52811 nrf52833 nrf52840 gp712 qpg7015m qpg6095 qpg6100 samr21 simulation posix)
 readonly OT_NRF528XX_BUILD_TYPES=(UART_trans USB_trans_bl SPI_trans_NCP soft_crypto soft_crypto_threading)
 readonly OT_POSIX_SIM_COMMON_OPTIONS=(
     "-DOT_BORDER_AGENT=ON"
@@ -131,6 +142,29 @@ readonly OT_nrf52833_OPTIONS=(
 
 readonly OT_nrf52840_OPTIONS=("${OT_nrf52833_OPTIONS[@]:0}")
 
+readonly OT_efr32_OPTIONS=(
+    "-DOT_DIAGNOSTIC=ON"
+    "-DOT_EXTERNAL_HEAP=ON"
+    "-DOT_EXTERNAL_MBEDTLS=silabs-mbedtls"
+    "-DOT_BUILTIN_MBEDTLS_MANAGEMENT=OFF"
+)
+
+readonly OT_efr32mg1_OPTIONS=(
+    "${OT_efr32_OPTIONS[@]:0}"
+)
+
+readonly OT_efr32mg12_OPTIONS=(
+    "${OT_efr32_OPTIONS[@]:0}"
+)
+
+readonly OT_efr32mg13_OPTIONS=(
+    "${OT_efr32_OPTIONS[@]:0}"
+)
+
+readonly OT_efr32mg21_OPTIONS=(
+    "${OT_efr32_OPTIONS[@]:0}"
+)
+
 die()
 {
     echo " ** ERROR: Openthread CMake doesn't support platform \"$1\""
@@ -209,6 +243,31 @@ main()
             OT_CMAKE_NINJA_TARGET=("ot-cli-ftd" "ot-rcp")
             options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-linux-gnueabihf.cmake" "-DCMAKE_BUILD_TYPE=Release")
             ;;
+        efr32*)
+            options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/efr32/${platform}/arm-none-eabi.cmake")
+
+            case "${platform}" in
+                efr32mg1)
+                    OT_CMAKE_NINJA_TARGET=("ot-rcp")
+                    options+=("${OT_efr32mg1_OPTIONS[@]}")
+                    ;;
+                efr32mg12)
+                    OT_CMAKE_NINJA_TARGET=("ot-rcp" "ot-cli-ftd" "ot-cli-mtd" "ot-ncp-ftd" "ot-ncp-mtd")
+                    OT_CMAKE_NINJA_TARGET+=("sleepy-demo-ftd" "sleepy-demo-mtd")
+                    options+=("${OT_efr32mg12_OPTIONS[@]}")
+                    ;;
+                efr32mg13)
+                    OT_CMAKE_NINJA_TARGET=("ot-rcp" "ot-cli-ftd" "ot-cli-mtd" "ot-ncp-ftd" "ot-ncp-mtd")
+                    OT_CMAKE_NINJA_TARGET+=("sleepy-demo-ftd" "sleepy-demo-mtd")
+                    options+=("${OT_efr32mg13_OPTIONS[@]}")
+                    ;;
+                efr32mg21)
+                    OT_CMAKE_NINJA_TARGET=("ot-rcp" "ot-cli-ftd" "ot-cli-mtd" "ot-ncp-ftd" "ot-ncp-mtd")
+                    OT_CMAKE_NINJA_TARGET+=("sleepy-demo-ftd" "sleepy-demo-mtd")
+                    options+=("${OT_efr32mg21_OPTIONS[@]}")
+                    ;;
+            esac
+            ;;
         nrf52811)
             local_options+=("${OT_nrf52811_OPTIONS[@]}" "-DCMAKE_TOOLCHAIN_FILE=examples/platforms/nrf528xx/${platform}/arm-none-eabi.cmake" "-DCMAKE_BUILD_TYPE=Release")
             case "${nrf_build_type}" in
diff --git a/third_party/CMakeLists.txt b/third_party/CMakeLists.txt
index 9e9120738..96ab34ab3 100644
--- a/third_party/CMakeLists.txt
+++ b/third_party/CMakeLists.txt
@@ -43,4 +43,7 @@ elseif(OT_PLATFORM STREQUAL "samr21")
 elseif(OT_PLATFORM MATCHES "^nrf*")
     add_subdirectory(jlink)
     add_subdirectory(NordicSemiconductor)
+elseif(OT_PLATFORM MATCHES "^efr*")
+    add_subdirectory(jlink)
+    add_subdirectory(silabs)
 endif()
diff --git a/third_party/jlink/CMakeLists.txt b/third_party/jlink/CMakeLists.txt
index f3e22bd39..e2b1e7f90 100644
--- a/third_party/jlink/CMakeLists.txt
+++ b/third_party/jlink/CMakeLists.txt
@@ -31,31 +31,37 @@ add_library(jlinkrtt
     SEGGER_RTT_V640/RTT/SEGGER_RTT.c
 )
 
-if(OT_PLATFORM STREQUAL "nrf52811")
-    target_compile_options(jlinkrtt PRIVATE
-        -DNRF52811_XXAA
-    )
-elseif(OT_PLATFORM STREQUAL "nrf52833")
-    target_compile_options(jlinkrtt PRIVATE
-        -DNRF52833_XXAA
-    )
-else()
-    target_compile_options(jlinkrtt PRIVATE
-        -DNRF52840_XXAA
-    )
-endif()
-
-target_compile_options(jlinkrtt PRIVATE
-    -DSEGGER_RTT_CONFIG_H=\"${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/segger_rtt/SEGGER_RTT_Conf.h\"
-    -DUSE_APP_CONFIG=1
-)
-
 target_include_directories(jlinkrtt PRIVATE
     ${PROJECT_SOURCE_DIR}/include
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/cmsis
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/config
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/config/${OT_PLATFORM}/config
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/dependencies
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/libraries/app_error
-    ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/nrfx/mdk
 )
+
+if(OT_PLATFORM MATCHES "^nrf*")
+
+    if(OT_PLATFORM STREQUAL "nrf52811")
+        target_compile_options(jlinkrtt PRIVATE
+            -DNRF52811_XXAA
+        )
+    elseif(OT_PLATFORM STREQUAL "nrf52833")
+        target_compile_options(jlinkrtt PRIVATE
+            -DNRF52833_XXAA
+        )
+    else()
+        target_compile_options(jlinkrtt PRIVATE
+            -DNRF52840_XXAA
+        )
+    endif()
+
+    target_compile_options(jlinkrtt PRIVATE
+        -DSEGGER_RTT_CONFIG_H=\"${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/segger_rtt/SEGGER_RTT_Conf.h\"
+        -DUSE_APP_CONFIG=1
+    )
+
+    target_include_directories(jlinkrtt PRIVATE
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/cmsis
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/config
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/config/${OT_PLATFORM}/config
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/dependencies
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/libraries/app_error
+        ${PROJECT_SOURCE_DIR}/third_party/NordicSemiconductor/nrfx/mdk
+    )
+endif()
diff --git a/third_party/silabs/CMakeLists.txt b/third_party/silabs/CMakeLists.txt
new file mode 100644
index 000000000..862c13f11
--- /dev/null
+++ b/third_party/silabs/CMakeLists.txt
@@ -0,0 +1,109 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/utility.cmake)
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/includes.cmake)
+
+# Append SILABS_GSDK_INCLUDES to OT_PUBLIC_INCLUDES
+list(APPEND OT_PUBLIC_INCLUDES ${SILABS_GSDK_INCLUDES})
+set(OT_PUBLIC_INCLUDES ${OT_PUBLIC_INCLUDES} PARENT_SCOPE)
+
+set(COMMON_FLAGS
+    -Wno-unused-parameter
+    -Wno-missing-field-initializers
+)
+
+set(SILABS_GSDK_COMMON_SOURCES
+    rail_config/rail_config.c
+    ${SILABS_GSDK_DIR}/hardware/kit/common/bsp/bsp_bcc.c
+    ${SILABS_GSDK_DIR}/hardware/kit/common/bsp/bsp_init.c
+    ${SILABS_GSDK_DIR}/hardware/kit/common/bsp/bsp_stk.c
+    ${SILABS_GSDK_DIR}/hardware/kit/common/bsp/bsp_stk_leds.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/dmadrv/src/dmadrv.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/gpiointerrupt/src/gpiointerrupt.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/src/nvm3_default_common_linker.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/src/nvm3_hal_flash.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/src/nvm3_lock.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/uartdrv/src/uartdrv.c
+    ${SILABS_GSDK_DIR}/platform/emdrv/ustimer/src/ustimer.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_cmu.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_core.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_emu.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_gpio.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_ldma.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_msc.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_rmu.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_rtcc.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_system.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_timer.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_usart.c
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/hal/efr32/hal_efr.c
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/hal/hal_common.c
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/plugin/pa-conversions/pa_conversions_efr32.c
+    ${SILABS_GSDK_DIR}/platform/service/mpu/src/sl_mpu.c
+    ${SILABS_GSDK_DIR}/platform/service/device_init/src/sl_device_init_nvic.c
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/src/sl_sleeptimer.c
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/src/sl_sleeptimer_hal_rtcc.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_alt/source/sl_entropy.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_alt/source/sl_mbedtls.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/mbedtls_sha.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_psa_driver_init.c
+)
+
+# ==============================================================================
+# Build RAIL lib name
+# ==============================================================================
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/imported_libs.cmake)
+
+# replace 'mg' with 'xg'
+string(REPLACE "mg" "xg" librail_platform_name ${OT_PLATFORM})
+
+if(DMP)
+    set(rail_dmp_string "multiprotocol_")
+else()
+    set(rail_dmp_string "")
+endif()
+
+set(silabs-librail "silabs-librail_${rail_dmp_string}${librail_platform_name}_gcc_release")
+
+# ==============================================================================
+# Platform GSDK lib
+# ==============================================================================
+set(platform_sdk_cmake "${CMAKE_CURRENT_SOURCE_DIR}/cmake/${OT_PLATFORM}.cmake")
+if(NOT EXISTS ${platform_sdk_cmake})
+    message(FATAL_ERROR "Platform unknown: ${OT_PLATFORM}")
+endif()
+include(${platform_sdk_cmake})
+
+# ==============================================================================
+# mbedtls
+# ==============================================================================
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/mbedtls.cmake)
+
+list(APPEND OT_PLATFORM_DEFINES "MBEDTLS_CONFIG_FILE=\"mbedtls_config.h\"")
+set(OT_PLATFORM_DEFINES ${OT_PLATFORM_DEFINES} PARENT_SCOPE)
diff --git a/third_party/silabs/Makefile.am b/third_party/silabs/Makefile.am
index ae8eb643e..3608e2c77 100644
--- a/third_party/silabs/Makefile.am
+++ b/third_party/silabs/Makefile.am
@@ -91,7 +91,6 @@ SILABS_MBEDTLS_CPPFLAGS
     -I$(SDK_SRC_DIR)/util/third_party/crypto/sl_component/sl_alt/include                    \
     -I$(SDK_SRC_DIR)/util/third_party/crypto/sl_component/sl_mbedtls_support/config         \
     -I$(SDK_SRC_DIR)/util/third_party/crypto/sl_component/sl_mbedtls_support/inc            \
-    -I$(SDK_SRC_DIR)/util/third_party/crypto/sl_component/sl_mbedtls_support/inc/configs    \
     -I$(SDK_SRC_DIR)/util/third_party/crypto/sl_component/sl_psa_driver/inc                 \
     -I$(SDK_SRC_DIR)/util/silicon_labs/silabs_core/memory_manager                           \
     -I$(SDK_SRC_DIR)/platform/CMSIS/Include                                                 \
diff --git a/third_party/silabs/cmake/efr32mg1.cmake b/third_party/silabs/cmake/efr32mg1.cmake
new file mode 100644
index 000000000..68d0a0119
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg1.cmake
@@ -0,0 +1,57 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/efr32mg1x.cmake)
+
+add_library(silabs-efr32mg1-sdk)
+
+target_compile_definitions(silabs-efr32mg1-sdk
+    PRIVATE
+        ${COMMON_FLAG}
+)
+
+target_include_directories(silabs-efr32mg1-sdk
+    PUBLIC
+        ${SILABS_COMMON_INCLUDES}
+        ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG1P/Include
+        ${SILABS_EFR32MG1X_INCLUDES}
+)
+
+target_sources(silabs-efr32mg1-sdk
+    PRIVATE
+        ${SILABS_GSDK_COMMON_SOURCES}
+        ${SILABS_EFR32MG1_SOURCES}
+)
+
+target_link_libraries(silabs-efr32mg1-sdk
+    PUBLIC
+        silabs-mbedtls
+    PRIVATE
+        ${silabs-librail}
+        ot-config
+)
diff --git a/third_party/silabs/cmake/efr32mg12.cmake b/third_party/silabs/cmake/efr32mg12.cmake
new file mode 100644
index 000000000..27675f038
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg12.cmake
@@ -0,0 +1,56 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/efr32mg1x.cmake)
+
+add_library(silabs-efr32mg12-sdk)
+
+target_compile_definitions(silabs-efr32mg12-sdk
+    PRIVATE
+        ${COMMON_FLAG}
+)
+
+target_include_directories(silabs-efr32mg12-sdk
+    PUBLIC
+        ${SILABS_COMMON_INCLUDES}
+        ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG12P/Include
+        ${SILABS_EFR32MG1X_INCLUDES}
+)
+
+target_sources(silabs-efr32mg12-sdk
+    PRIVATE
+        ${SILABS_GSDK_COMMON_SOURCES}
+        ${SILABS_EFR32MG12_SOURCES}
+)
+
+target_link_libraries(silabs-efr32mg12-sdk
+    PUBLIC
+        silabs-mbedtls
+    PRIVATE
+        ${silabs-librail}
+        ot-config)
diff --git a/third_party/silabs/cmake/efr32mg13.cmake b/third_party/silabs/cmake/efr32mg13.cmake
new file mode 100644
index 000000000..06ef0e5fb
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg13.cmake
@@ -0,0 +1,56 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/efr32mg1x.cmake)
+
+add_library(silabs-efr32mg13-sdk)
+
+target_compile_definitions(silabs-efr32mg13-sdk
+    PRIVATE
+        ${COMMON_FLAG}
+)
+
+target_include_directories(silabs-efr32mg13-sdk
+    PUBLIC
+        ${SILABS_COMMON_INCLUDES}
+        ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG13P/Include
+        ${SILABS_EFR32MG1X_INCLUDES}
+)
+
+target_sources(silabs-efr32mg13-sdk
+    PRIVATE
+        ${SILABS_GSDK_COMMON_SOURCES}
+        ${SILABS_EFR32MG13_SOURCES}
+)
+
+target_link_libraries(silabs-efr32mg13-sdk
+    PUBLIC
+        silabs-mbedtls
+    PRIVATE
+        ${silabs-librail}
+        ot-config)
diff --git a/third_party/silabs/cmake/efr32mg1x.cmake b/third_party/silabs/cmake/efr32mg1x.cmake
new file mode 100644
index 000000000..1bba23a8f
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg1x.cmake
@@ -0,0 +1,67 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Series-level _SOURCES
+# ==============================================================================
+set(SILABS_EFR32MG1X_SOURCES
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_adc.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_crypto.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_leuart.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/crypto_aes.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/crypto_ecp.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/crypto_management.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_crypto_transparent_driver_aead.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_crypto_transparent_driver_cipher.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_crypto_transparent_driver_hash.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_crypto_transparent_driver_mac.c
+)
+
+
+# ==============================================================================
+# Platform-level _SOURCES
+# ==============================================================================
+set(SILABS_EFR32MG1_SOURCES
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG1P/Source/system_efr32mg1p.c
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG1P/Source/GCC/startup_efr32mg1p.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_alt/source/sl_entropy_adc.c
+    ${SILABS_EFR32MG1X_SOURCES}
+)
+
+set(SILABS_EFR32MG12_SOURCES
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG12P/Source/system_efr32mg12p.c
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG12P/Source/GCC/startup_efr32mg12p.c
+    ${SILABS_EFR32MG1X_SOURCES}
+)
+
+set(SILABS_EFR32MG13_SOURCES
+    ${SILABS_GSDK_DIR}/hardware/kit/common/drivers/mx25flash_spi.c
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG13P/Source/system_efr32mg13p.c
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG13P/Source/GCC/startup_efr32mg13p.c
+    ${SILABS_EFR32MG1X_SOURCES}
+)
diff --git a/third_party/silabs/cmake/efr32mg21.cmake b/third_party/silabs/cmake/efr32mg21.cmake
new file mode 100644
index 000000000..8795e1109
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg21.cmake
@@ -0,0 +1,57 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/efr32mg2x.cmake)
+
+add_library(silabs-efr32mg21-sdk)
+
+target_compile_definitions(silabs-efr32mg21-sdk
+    PRIVATE
+        ${COMMON_FLAG}
+)
+
+target_include_directories(silabs-efr32mg21-sdk
+    PUBLIC
+        ${SILABS_COMMON_INCLUDES}
+        ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG21/Include
+        ${SILABS_EFR32MG2X_INCLUDES}
+)
+
+target_sources(silabs-efr32mg21-sdk
+    PUBLIC
+        ${SILABS_EFR32MG21_SOURCES}
+    PRIVATE
+        ${SILABS_GSDK_COMMON_SOURCES}
+)
+
+target_link_libraries(silabs-efr32mg21-sdk
+    PUBLIC
+        silabs-mbedtls
+    PRIVATE
+        ${silabs-librail}
+        ot-config)
diff --git a/third_party/silabs/cmake/efr32mg2x.cmake b/third_party/silabs/cmake/efr32mg2x.cmake
new file mode 100644
index 000000000..445311433
--- /dev/null
+++ b/third_party/silabs/cmake/efr32mg2x.cmake
@@ -0,0 +1,79 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# Series-level _SOURCES
+# ==============================================================================
+set(SILABS_EFR32MG2X_SOURCES
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_burtc.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_prs.c
+    ${SILABS_GSDK_DIR}/platform/emlib/src/em_se.c
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/src/sl_sleeptimer_hal_burtc.c
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/src/sl_sleeptimer_hal_prortc.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_attestation.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_cipher.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_entropy.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_hash.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_key_derivation.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_key_handling.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_signature.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager_util.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src/sl_se_manager.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_alt/source/sl_se_management.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/mbedtls_cmac.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/mbedtls_ecdsa_ecdh.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/se_aes.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/se_ccm.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/src/se_jpake.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_aead.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_builtin_keys.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_cipher.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_key_derivation.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_key_management.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_mac.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_driver_signature.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_opaque_driver_aead.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_opaque_driver_cipher.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_opaque_driver_mac.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_opaque_key_derivation.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_transparent_driver_aead.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_transparent_driver_cipher.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_transparent_driver_hash.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_transparent_driver_mac.c
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/src/sli_se_transparent_key_derivation.c
+)
+
+
+# ==============================================================================
+# Platform-level _SOURCES
+# ==============================================================================
+set(SILABS_EFR32MG21_SOURCES
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG21/Source/system_efr32mg21.c
+    ${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG21/Source/GCC/startup_efr32mg21.c
+    ${SILABS_EFR32MG2X_SOURCES}
+)
diff --git a/third_party/silabs/cmake/imported_libs.cmake b/third_party/silabs/cmake/imported_libs.cmake
new file mode 100644
index 000000000..c09d79fb4
--- /dev/null
+++ b/third_party/silabs/cmake/imported_libs.cmake
@@ -0,0 +1,74 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# ==============================================================================
+# RAIL libs
+# ==============================================================================
+set(librail_release_dir "${SILABS_GSDK_DIR}/platform/radio/rail_lib/autogen/librail_release")
+file(GLOB rail_libs ${librail_release_dir}/*.a)
+
+foreach(lib_file ${rail_libs})
+
+    # Parse lib name, stripping .a extension
+    get_filename_component(lib_name ${lib_file} NAME_WLE)
+    set(imported_lib_name "silabs-${lib_name}")
+
+    # Add as an IMPORTED lib
+    add_library(${imported_lib_name} STATIC IMPORTED)
+    set_target_properties(${imported_lib_name}
+        PROPERTIES
+            IMPORTED_LOCATION "${lib_file}"
+            IMPORTED_LINK_INTERFACE_LIBRARIES silabs-${PLATFORM_LOWERCASE}-sdk
+    )
+
+endforeach()
+
+
+# ==============================================================================
+# NVM3 libs
+# ==============================================================================
+set(libnvm3_release_dir "${SILABS_GSDK_DIR}/platform/emdrv/nvm3/lib")
+file(GLOB nvm3_libs ${libnvm3_release_dir}/*.a)
+
+foreach(lib_file ${nvm3_libs})
+
+    # Parse lib name, stripping .a extension
+    get_filename_component(lib_name ${lib_file} NAME_WLE)
+    set(imported_lib_name "silabs-${lib_name}")
+
+    # Add as an IMPORTED lib
+    add_library(${imported_lib_name} STATIC IMPORTED)
+    set_target_properties(${imported_lib_name}
+        PROPERTIES
+            IMPORTED_LOCATION "${lib_file}"
+            IMPORTED_LINK_INTERFACE_LIBRARIES silabs-${PLATFORM_LOWERCASE}-sdk
+    )
+
+endforeach()
+
+
diff --git a/third_party/silabs/cmake/includes.cmake b/third_party/silabs/cmake/includes.cmake
new file mode 100644
index 000000000..23bdd6f13
--- /dev/null
+++ b/third_party/silabs/cmake/includes.cmake
@@ -0,0 +1,103 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+set(SILABS_GSDK_INCLUDES
+    ${SILABS_GSDK_DIR}
+    ${SILABS_GSDK_DIR}/hardware/kit/${PLATFORM_UPPERCASE}_${BOARD_UPPERCASE}/config
+    ${SILABS_GSDK_DIR}/hardware/kit/common/bsp
+    ${SILABS_GSDK_DIR}/hardware/kit/common/drivers
+    ${SILABS_GSDK_DIR}/platform/base/hal/micro/cortexm3/efm32
+    ${SILABS_GSDK_DIR}/platform/base/hal/micro/cortexm3/efm32/config
+    ${SILABS_GSDK_DIR}/platform/base/hal/plugin/antenna/
+    ${SILABS_GSDK_DIR}/platform/CMSIS/Include
+    ${SILABS_GSDK_DIR}/platform/common/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/common/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/dmadrv/config
+    ${SILABS_GSDK_DIR}/platform/emdrv/dmadrv/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/gpiointerrupt/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/config
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/uartdrv/config
+    ${SILABS_GSDK_DIR}/platform/emdrv/uartdrv/inc
+    ${SILABS_GSDK_DIR}/platform/emdrv/ustimer/inc
+    ${SILABS_GSDK_DIR}/platform/emlib/inc
+    ${SILABS_GSDK_DIR}/platform/halconfig/inc/hal-config
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/chip/efr32
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/common
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/hal
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/hal/efr32
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/plugin/pa-conversions
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/protocol/ieee802154
+    ${SILABS_GSDK_DIR}/platform/service/device_init/inc
+    ${SILABS_GSDK_DIR}/platform/service/mpu/inc
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/config
+    ${SILABS_GSDK_DIR}/platform/service/sleeptimer/inc
+    ${SILABS_GSDK_DIR}/util/plugin/plugin-common/fem-control
+)
+
+file(GLOB gsdk_board_config_dir "${SILABS_GSDK_DIR}/hardware/board/config/*${BOARD_LOWERCASE}*")
+list(APPEND SILABS_GSDK_INCLUDES ${gsdk_board_config_dir})
+
+if(PLATFORM_LOWERCASE STREQUAL "efr32mg1")
+    set(gsdk_platform_device_silicon_labs_include_dir "${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG1P/Include")
+elseif(PLATFORM_LOWERCASE STREQUAL "efr32mg12")
+    set(gsdk_platform_device_silicon_labs_include_dir "${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG12P/Include")
+elseif(PLATFORM_LOWERCASE STREQUAL "efr32mg13")
+    set(gsdk_platform_device_silicon_labs_include_dir "${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG13P/Include")
+elseif(PLATFORM_LOWERCASE STREQUAL "efr32mg21")
+    set(gsdk_platform_device_silicon_labs_include_dir "${SILABS_GSDK_DIR}/platform/Device/SiliconLabs/EFR32MG21/Include")
+endif()
+list(APPEND SILABS_GSDK_INCLUDES ${gsdk_platform_device_silicon_labs_include_dir})
+
+set(SILABS_COMMON_INCLUDES
+    ${PROJECT_SOURCE_DIR}/examples/platforms
+    ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/src
+    ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/${PLATFORM_LOWERCASE}/crypto
+    ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/${PLATFORM_LOWERCASE}/${BOARD_LOWERCASE}
+    ${PROJECT_SOURCE_DIR}/third_party/silabs/rail_config
+    ${SILABS_GSDK_INCLUDES}
+    ${PROJECT_SOURCE_DIR}/include
+    ${PROJECT_SOURCE_DIR}/src
+    ${PROJECT_SOURCE_DIR}/src/core
+)
+
+# ==============================================================================
+# Series-level CPPFLAGS
+# ==============================================================================
+set(SILABS_EFR32MG1X_INCLUDES
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/config/s1
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/chip/efr32/efr32xg1x
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/plugin/pa-conversions/efr32xg1x/config
+)
+set(SILABS_EFR32MG2X_INCLUDES
+    ${SILABS_GSDK_DIR}/platform/emdrv/nvm3/config/s2
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/chip/efr32/efr32xg2x
+    ${SILABS_GSDK_DIR}/platform/radio/rail_lib/plugin/pa-conversions/efr32xg21/config
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/inc
+    ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src
+)
diff --git a/third_party/silabs/cmake/mbedtls.cmake b/third_party/silabs/cmake/mbedtls.cmake
new file mode 100644
index 000000000..9ad716df8
--- /dev/null
+++ b/third_party/silabs/cmake/mbedtls.cmake
@@ -0,0 +1,117 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+include(${PROJECT_SOURCE_DIR}/third_party/silabs/cmake/utility.cmake)
+
+add_library(silabs-mbedtls)
+
+set_target_properties(silabs-mbedtls
+    PROPERTIES
+        C_STANDARD 99
+        CXX_STANDARD 11
+)
+
+set(SILABS_MBEDTLS_DIR "${SILABS_GSDK_DIR}/util/third_party/crypto/mbedtls")
+
+target_compile_definitions(silabs-mbedtls
+    PRIVATE
+        ${OT_PLATFORM_DEFINES}
+)
+
+target_include_directories(silabs-mbedtls
+    PUBLIC
+        ${SILABS_MBEDTLS_DIR}/include
+        ${SILABS_MBEDTLS_DIR}/include/mbedtls
+        ${SILABS_MBEDTLS_DIR}/library
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_alt/include
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/config
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_mbedtls_support/inc
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/sl_psa_driver/inc
+        ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/${PLATFORM_LOWERCASE}/crypto
+        ${SILABS_GSDK_DIR}/util/silicon_labs/silabs_core/memory_manager
+    PRIVATE
+        ${SILABS_GSDK_DIR}/platform/CMSIS/Include
+        ${SILABS_GSDK_DIR}/platform/common/inc/
+        ${SILABS_GSDK_DIR}/platform/emlib/inc
+        ${SILABS_GSDK_DIR}/platform/radio/rail_lib/common
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/inc
+        ${SILABS_GSDK_DIR}/util/third_party/crypto/sl_component/se_manager/src
+        ${gsdk_platform_device_silicon_labs_include_dir}
+        ${PROJECT_SOURCE_DIR}/examples/platforms/efr32/src
+)
+
+set(SILABS_MBEDTLS_SOURCES
+    ${SILABS_MBEDTLS_DIR}/library/aes.c
+    ${SILABS_MBEDTLS_DIR}/library/asn1parse.c
+    ${SILABS_MBEDTLS_DIR}/library/asn1write.c
+    ${SILABS_MBEDTLS_DIR}/library/base64.c
+    ${SILABS_MBEDTLS_DIR}/library/bignum.c
+    ${SILABS_MBEDTLS_DIR}/library/ccm.c
+    ${SILABS_MBEDTLS_DIR}/library/cipher_wrap.c
+    ${SILABS_MBEDTLS_DIR}/library/cipher.c
+    ${SILABS_MBEDTLS_DIR}/library/cmac.c
+    ${SILABS_MBEDTLS_DIR}/library/ctr_drbg.c
+    ${SILABS_MBEDTLS_DIR}/library/des.c
+    ${SILABS_MBEDTLS_DIR}/library/ecdh.c
+    ${SILABS_MBEDTLS_DIR}/library/ecdsa.c
+    ${SILABS_MBEDTLS_DIR}/library/ecjpake.c
+    ${SILABS_MBEDTLS_DIR}/library/ecp_curves.c
+    ${SILABS_MBEDTLS_DIR}/library/ecp.c
+    ${SILABS_MBEDTLS_DIR}/library/entropy.c
+    ${SILABS_MBEDTLS_DIR}/library/error.c
+    ${SILABS_MBEDTLS_DIR}/library/md.c
+    ${SILABS_MBEDTLS_DIR}/library/oid.c
+    ${SILABS_MBEDTLS_DIR}/library/pem.c
+    ${SILABS_MBEDTLS_DIR}/library/pk_wrap.c
+    ${SILABS_MBEDTLS_DIR}/library/pk.c
+    ${SILABS_MBEDTLS_DIR}/library/pkparse.c
+    ${SILABS_MBEDTLS_DIR}/library/platform_util.c
+    ${SILABS_MBEDTLS_DIR}/library/platform.c
+    ${SILABS_MBEDTLS_DIR}/library/rsa_internal.c
+    ${SILABS_MBEDTLS_DIR}/library/rsa.c
+    ${SILABS_MBEDTLS_DIR}/library/sha256.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_cache.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_ciphersuites.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_cli.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_cookie.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_msg.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_srv.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_ticket.c
+    ${SILABS_MBEDTLS_DIR}/library/ssl_tls.c
+    ${SILABS_MBEDTLS_DIR}/library/threading.c
+    ${SILABS_MBEDTLS_DIR}/library/x509_create.c
+    ${SILABS_MBEDTLS_DIR}/library/x509_crl.c
+    ${SILABS_MBEDTLS_DIR}/library/x509_crt.c
+    ${SILABS_MBEDTLS_DIR}/library/x509_csr.c
+    ${SILABS_MBEDTLS_DIR}/library/x509.c
+    ${SILABS_MBEDTLS_DIR}/library/x509write_crt.c
+    ${SILABS_MBEDTLS_DIR}/library/x509write_csr.c
+    ${SILABS_GSDK_DIR}/util/silicon_labs/silabs_core/memory_manager/sl_malloc.c
+)
+
+target_sources(silabs-mbedtls PRIVATE ${SILABS_MBEDTLS_SOURCES})
diff --git a/third_party/silabs/cmake/utility.cmake b/third_party/silabs/cmake/utility.cmake
new file mode 100644
index 000000000..b212cf779
--- /dev/null
+++ b/third_party/silabs/cmake/utility.cmake
@@ -0,0 +1,44 @@
+#
+#  Copyright (c) 2021, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+# Alias OT_PLATFORM as EFR32_PLATFORM
+set(EFR32_PLATFORM ${OT_PLATFORM})
+
+string(TOLOWER "${EFR32_PLATFORM}" PLATFORM_LOWERCASE)
+string(TOUPPER "${EFR32_PLATFORM}" PLATFORM_UPPERCASE)
+
+string(TOLOWER "${BOARD}" BOARD_LOWERCASE)
+string(TOUPPER "${BOARD}" BOARD_UPPERCASE)
+
+set(SILABS_GSDK_VERSION 3.1)
+set(SILABS_GSDK_DIR ${PROJECT_SOURCE_DIR}/third_party/silabs/gecko_sdk_suite/v${SILABS_GSDK_VERSION})
+
+# Check if GSDK exists
+if(NOT EXISTS "${SILABS_GSDK_DIR}")
+    message(FATAL_ERROR "Cannot find: ${SILABS_GSDK_DIR}\nCheck that Silicon Labs GSDK ${SILABS_GSDK_VERSION} was installed properly")
+endif()