feat: Add support for NVS image generation from CMake

Closes: https://github.com/espressif/esp-idf/pull/11926
Closes: https://github.com/espressif/esp-idf/pull/11785

Co-authored-by: Nebojša Cvetković <nebkat@gmail.com>

components/nvs_flash/project_include.cmake

@@ -0,0 +1,64 @@
+# nvs_create_partition_image
+#
+# Create a NVS image of the specified CSV on the host during build and
+# optionally have the created image flashed using `idf.py flash`
+function(nvs_create_partition_image partition csv)
+    set(options FLASH_IN_PROJECT)
+    set(one VERSION)
+    set(multi DEPENDS)
+    cmake_parse_arguments(arg "${options}" "${one}" "${multi}" "${ARGN}")
+
+    # Default to version 2
+    if(NOT DEFINED arg_VERSION)
+        set(arg_VERSION 2)
+    endif()
+
+    idf_build_get_property(idf_path IDF_PATH)
+    set(nvs_partition_gen_py
+        ${PYTHON}
+        ${idf_path}/components/nvs_flash/nvs_partition_generator/nvs_partition_gen.py
+       )
+
+    get_filename_component(csv_full_path ${csv} ABSOLUTE)
+
+    partition_table_get_partition_info(size "--partition-name ${partition}" "size")
+    partition_table_get_partition_info(offset "--partition-name ${partition}" "offset")
+
+    if("${size}" AND "${offset}")
+        set(image_file ${CMAKE_BINARY_DIR}/${partition}.bin)
+
+        add_custom_command(
+            OUTPUT ${image_file}
+            COMMAND ${nvs_partition_gen_py} generate --version ${arg_VERSION} ${csv_full_path} ${image_file} ${size}
+            MAIN_DEPENDENCY ${csv_full_path}
+            DEPENDS ${arg_DEPENDS}
+            COMMENT "Generating NVS partition image for ${partition} from ${csv}"
+           )
+
+        add_custom_target(nvs_${partition}_bin ALL DEPENDS ${image_file})
+
+        set_property(
+            DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+            APPEND
+            PROPERTY ADDITIONAL_CLEAN_FILES ${image_file}
+           )
+
+        idf_component_get_property(main_args esptool_py FLASH_ARGS)
+        idf_component_get_property(sub_args esptool_py FLASH_SUB_ARGS)
+        esptool_py_flash_target(${partition}-flash "${main_args}" "${sub_args}" ALWAYS_PLAINTEXT)
+        esptool_py_flash_to_partition(${partition}-flash "${partition}" "${image_file}")
+
+        add_dependencies(${partition}-flash nvs_${partition}_bin)
+
+        if(arg_FLASH_IN_PROJECT)
+            esptool_py_flash_to_partition(flash "${partition}" "${image_file}")
+            add_dependencies(flash nvs_${partition}_bin)
+        endif()
+    else()
+        set(message
+            "Failed to create NVS image for partition '${partition}'. "
+            "Check project configuration if using the correct partition table file."
+           )
+        fail_at_build_time(nvs_${partition}_bin "${message}")
+    endif()
+endfunction()

docs/en/api-reference/storage/nvs_flash.rst

@@ -92,6 +92,40 @@ NVS Partition Generator Utility
 
 This utility helps generate NVS partition binary files which can be flashed separately on a dedicated partition via a flashing utility. Key-value pairs to be flashed onto the partition can be provided via a CSV file. For more details, please refer to :doc:`nvs_partition_gen`.
 
+Instead of calling the ``nvs_partition_gen.py`` tool manually, the creation of the partition binary files can also be done directly from CMake using the function ``nvs_create_partition_image``::
+
+    nvs_create_partition_image(<partition> <csv> [FLASH_IN_PROJECT] [VERSION 1 | 2] [DEPENDS  dep dep dep ...])
+
+**Positional Arguments**:
+
++---------------+---------------------------------------------------------------+
+| Parameter     | Description                                                   |
++===============+===============================================================+
+| ``partition`` | Name of the NVS parition                                      |
++---------------+---------------------------------------------------------------+
+| ``csv``       | Path to CSV file to parse                                     |
++---------------+---------------------------------------------------------------+
+
+**Optional Arguments**:
+
++----------------------+----------------------------------------------------------------------+
+| Parameter            | Description                                                          |
++======================+======================================================================+
+| ``FLASH_IN_PROJECT`` | Flash the image when using ``idf.py flash``                          |
++----------------------+----------------------------------------------------------------------+
+| ``VERSION``          | Set multipage blob version (Default: Version 2)                      |
+|                      |                                                                      |
+|                      | Version 1 - Multipage blob support disabled                          |
+|                      |                                                                      |
+|                      | Version 2 - Multipage blob support enabled                           |
++----------------------+----------------------------------------------------------------------+
+| ``DEPENDS``          | Specify files on which the command depends                           |
++----------------------+----------------------------------------------------------------------+
+
+If FLASH_IN_PROJECT is not specified, the image will still be generated, but you will have to flash it manually using ``idf.py <partition>-flash`` (e.g. if your parition name is ``nvs`` ``idf.py nvs-flash``).
+
+``nvs_create_partition_image`` must be called from one of the component ``CMakeLists.txt`` files. Currently only non-encrypted partitions are supported.
+
 Application Example
 -------------------