esptool_py: Adds funcs to read eFuses from Cmake during a build stage

Closes https://github.com/espressif/esp-idf/issues/10311

components/esptool_py/espefuse.cmake

@@ -0,0 +1,47 @@
+cmake_minimum_required(VERSION 3.16)
+
+# Executes a espefuse.py command and returns a cleaned log
+function(espefuse_cmd cmd output_log)
+    set(SERIAL_TOOL ${ESPEFUSEPY})
+    if(${ESPEFUSEPY_OFFLINE})
+        set(VIRT_OPTION "--virt")
+    endif()
+    set(SERIAL_TOOL_ARGS ${VIRT_OPTION} "--chip;${IDF_TARGET};${cmd}")
+    set(SERIAL_TOOL_SILENT 1)
+    include(${esptool_py_dir}/run_serial_tool.cmake)
+    set(log ${SERIAL_TOOL_OUTPUT_LOG})
+
+    set(prefix_str " command ===")
+    string(FIND ${log} ${prefix_str} pos)
+    if(${pos} GREATER -1)
+        string(LENGTH ${prefix_str} len_of_prefix_str)
+        math(EXPR pos "${pos} + ${len_of_prefix_str}")
+        string(SUBSTRING ${log} ${pos} -1 final_log)
+    else()
+        set(final_log ${log})
+    endif()
+
+    set(${output_log} ${final_log} PARENT_SCOPE)
+endfunction()
+
+# Reads efuses "espefuse.py summary" and returns JSON string
+function(espefuse_get_json_summary json_str)
+    espefuse_cmd("summary;--format;json" output_log)
+    set(${json_str} ${output_log} PARENT_SCOPE)
+endfunction()
+
+# See the esp-idf/docs/en/api-reference/system/efuse.rst "Get eFuses During Build".
+#
+# It takes the efuse json string and returns a value of property for a given efuse name
+function(espefuse_get_efuse result efuse_json efuse_name efuse_property)
+    if(${CMAKE_VERSION} VERSION_LESS "3.19.0")
+        string(REGEX MATCH "\"${efuse_name}\":[ \t\n\r]*\{[^\}]*\}" cur_efuse ${efuse_json})
+        string(REGEX MATCH "\"${efuse_property}\":[ \t\n\r]*\"?([^,\"]*)\"?," ret_value ${cur_efuse})
+        set(${result} ${CMAKE_MATCH_1} PARENT_SCOPE)
+    else()
+        # The JSON feature has been supported by Cmake since 3.19.0
+        string(JSON cur_efuse GET ${efuse_json} ${efuse_name})
+        string(JSON ret_value GET ${cur_efuse} ${efuse_property})
+        set(${result} ${ret_value} PARENT_SCOPE)
+    endif()
+endfunction()

components/esptool_py/project_include.cmake

@@ -494,3 +494,7 @@ if(NOT BOOTLOADER_BUILD)
 
     esptool_py_custom_target(flash project "${flash_deps}")
 endif()
+
+# Adds espefuse functions for global use
+idf_component_get_property(esptool_py_dir esptool_py COMPONENT_DIR)
+include(${esptool_py_dir}/espefuse.cmake)

components/esptool_py/run_serial_tool.cmake

@@ -45,12 +45,20 @@ endif()
 
 list(APPEND serial_tool_cmd ${SERIAL_TOOL_ARGS})
 
-execute_process(COMMAND ${serial_tool_cmd}
-    WORKING_DIRECTORY "${WORKING_DIRECTORY}"
-    RESULT_VARIABLE result
+if(${SERIAL_TOOL_SILENT})
+    execute_process(COMMAND ${serial_tool_cmd}
+        WORKING_DIRECTORY "${WORKING_DIRECTORY}"
+        RESULT_VARIABLE result
+        OUTPUT_VARIABLE SERIAL_TOOL_OUTPUT_LOG
     )
+else()
+    execute_process(COMMAND ${serial_tool_cmd}
+        WORKING_DIRECTORY "${WORKING_DIRECTORY}"
+        RESULT_VARIABLE result
+    )
+endif()
 
 if(${result})
     # No way to have CMake silently fail, unfortunately
-    message(FATAL_ERROR "${SERIAL_TOOL} failed")
+    message(FATAL_ERROR "${SERIAL_TOOL} failed. \n${SERIAL_TOOL_OUTPUT_LOG}")
 endif()

docs/en/api-reference/system/efuse.rst

@@ -401,6 +401,53 @@ Thus, reading the eFuse ``USER_DATA`` block written as above gives the following
     // id = 0x01
     // b'001
 
+Get eFuses During Build
+-----------------------
+
+There is a way to get the state of eFuses at the build stage of the project. There are two cmake functions for this:
+
+* ``espefuse_get_json_summary()`` - It calls the ``espefuse.py summary --format json`` command and returns a json string (it is not stored in a file).
+* ``espefuse_get_efuse()`` - It finds a given eFuse name in the json string and returns its property.
+
+The json string has the following properties:
+
+.. code-block:: json
+
+    {
+        "MAC": {
+            "bit_len": 48,
+            "block": 0,
+            "category": "identity",
+            "description": "Factory MAC Address",
+            "efuse_type": "bytes:6",
+            "name": "MAC",
+            "pos": 0,
+            "readable": true,
+            "value": "94:b9:7e:5a:6e:58 (CRC 0xe2 OK)",
+            "word": 1,
+            "writeable": true
+        },
+    }
+
+These functions can be used from a top-level project ``CMakeLists.txt`` (:example_file:`get-started/hello_world/CMakeLists.txt`):
+
+.. code-block:: cmake
+
+    # ...
+    project(hello_world)
+
+    espefuse_get_json_summary(efuse_json)
+    espefuse_get_efuse(ret_data ${efuse_json} "MAC" "value")
+    message("MAC:" ${ret_data})
+
+The format of the ``value`` property is the same as shown in ``espefuse.py summary``.
+
+.. code-block:: none
+
+    MAC:94:b9:7e:5a:6e:58 (CRC 0xe2 OK)
+
+There is an example test :example_file:`system/efuse/CMakeLists.txt` which adds a custom target ``efuse-summary``. This allows you to run the ``idf.py efuse-summary`` command to read the required eFuses (specified in the ``efuse_names`` list) at any time, not just at project build time.
+
 Debug eFuse & Unit tests
 ------------------------
 

examples/system/efuse/CMakeLists.txt

@@ -4,3 +4,19 @@ cmake_minimum_required(VERSION 3.16)
 
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 project(efuse)
+
+idf_component_get_property(esptool_py_dir esptool_py COMPONENT_DIR)
+set(efuse_names "MAC" "WR_DIS")
+add_custom_target(efuse-summary
+    COMMAND ${CMAKE_COMMAND}
+    -D "IDF_PATH=${IDF_PATH}"
+    -D "esptool_py_dir=${esptool_py_dir}"
+    -D "ESPEFUSEPY=${ESPEFUSEPY}"
+    -D "ESPEFUSEPY_OFFLINE=${CONFIG_IDF_CI_BUILD}" # Only for CI tests. Do not establish a connection with the chip
+    -D "IDF_TARGET=${IDF_TARGET}"
+    -D "efuse_names=${efuse_names}"
+    -P get_efuse_summary.cmake
+    WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+    USES_TERMINAL
+    VERBATIM
+    )

examples/system/efuse/get_efuse_summary.cmake

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.16)
+
+include(${esptool_py_dir}/espefuse.cmake)
+espefuse_get_json_summary(efuse_json)
+foreach(name ${efuse_names})
+    espefuse_get_efuse(ret_data ${efuse_json} ${name} "value")
+    message(STATUS "FROM_CMAKE: ${name}: ${ret_data}")
+endforeach()

tools/test_build_system/test_common.py

@@ -1,4 +1,4 @@
-# SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+# SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
 # SPDX-License-Identifier: Apache-2.0
 import shutil
 import subprocess
@@ -71,3 +71,15 @@ def test_idf_build_with_env_var_sdkconfig_defaults(
 
     with open(test_app_copy / 'sdkconfig') as fr:
         assert 'CONFIG_BT_ENABLED=y' in fr.read()
+
+
+@pytest.mark.usefixtures('test_app_copy')
+@pytest.mark.test_app_copy('examples/system/efuse')
+def test_efuse_symmary_cmake_functions(
+    idf_py: IdfPyFunc,
+    monkeypatch: MonkeyPatch
+) -> None:
+    monkeypatch.setenv('IDF_CI_BUILD', '1')
+    output = idf_py('efuse-summary')
+    assert 'FROM_CMAKE: MAC: 00:00:00:00:00:00' in output.stdout
+    assert 'FROM_CMAKE: WR_DIS: 0' in output.stdout