feature: add build framework support

Kconfig

@@ -141,13 +141,15 @@ mainmenu "Espressif IoT Development Framework Configuration"
 
                 Another option, useful for only very small and limited applications, is to only link
                 the .elf file of the application, such that it can be loaded directly into RAM over
-                JTAG. Note that since IRAM and DRAM sizes are very limited, it is not possible to
-                build any complex application this way. However for kinds of testing and debugging,
+                JTAG or UART. Note that since IRAM and DRAM sizes are very limited, it is not possible
+                to build any complex application this way. However for some kinds of testing and debugging,
                 this option may provide faster iterations, since the application does not need to be
                 written into flash.
-                Note that at the moment, ESP-IDF does not contain all the startup code required to
-                initialize the CPUs and ROM memory (data/bss). Therefore it is necessary to execute
-                a bit of ROM code prior to executing the application. A gdbinit file may look as follows (for ESP32):
+
+                Note: when APP_BUILD_TYPE_RAM is selected and loaded with JTAG, ESP-IDF does not contain
+                all the startup code required to initialize the CPUs and ROM memory (data/bss).
+                Therefore it is necessary to execute a bit of ROM code prior to executing the application.
+                A gdbinit file may look as follows (for ESP32):
 
                     # Connect to a running instance of OpenOCD
                     target remote :3333
@@ -169,6 +171,13 @@ mainmenu "Espressif IoT Development Framework Configuration"
 
                 Example gdbinit files for other targets can be found in tools/test_apps/system/gdb_loadable_elf/
 
+                When loading the BIN with UART, the ROM will jump to ram and run the app after finishing the ROM
+                startup code, so there's no additional startup initialization required. You can use the
+                `load_ram` in esptool.py to load the generated .bin file into ram and execute.
+
+                Example:
+                    esptool.py --chip {chip} -p {port} -b {baud} --no-stub load_ram {app.bin}
+
                 Recommended sdkconfig.defaults for building loadable ELF files is as follows.
                 CONFIG_APP_BUILD_TYPE_RAM is required, other options help reduce application
                 memory footprint.
@@ -189,9 +198,11 @@ mainmenu "Espressif IoT Development Framework Configuration"
                 select APP_BUILD_BOOTLOADER
                 select APP_BUILD_USE_FLASH_SECTIONS
 
-            config APP_BUILD_TYPE_ELF_RAM
+            config APP_BUILD_TYPE_RAM
                 bool
-                prompt "ELF file, loadable into RAM (EXPERIMENTAL))"
+                prompt "Build app runs entirely in RAM (EXPERIMENTAL)"
+                select APP_BUILD_GENERATE_BINARIES
+
         endchoice # APP_BUILD_TYPE
 
         # Hidden options, set according to the choice above
@@ -201,6 +212,16 @@ mainmenu "Espressif IoT Development Framework Configuration"
         config APP_BUILD_BOOTLOADER
             bool # Whether to build the bootloader
 
+        config APP_BUILD_TYPE_PURE_RAM_APP
+            bool
+            prompt "Build app without SPI_FLASH/PSRAM support (saves ram)"
+            depends on APP_BUILD_TYPE_RAM
+            help
+                If this option is enabled, external memory and related peripherals, such as Cache, MMU,
+                Flash and PSRAM, won't be initialized. Corresponding drivers won't be introduced either.
+                Components that depend on the spi_flash component will also be unavailable, such as
+                app_update, etc. When this option is enabled, about 26KB of RAM space can be saved.
+
         config APP_BUILD_USE_FLASH_SECTIONS
             bool # Whether to place code/data into memory-mapped flash sections
 

components/esptool_py/CMakeLists.txt

@@ -48,7 +48,7 @@ consist of two ota app without factory or test partitions.")
                     CONTENT "${flasher_args_content}")
         file_generate("${CMAKE_BINARY_DIR}/flasher_args.json"
                     INPUT "${CMAKE_CURRENT_BINARY_DIR}/flasher_args.json.in")
-
+        if(CONFIG_APP_BUILD_TYPE_APP_2NDBOOT)
             # Generate app_check_size_command target to check the app size against the partition table parameters
             partition_table_add_check_size_target(app_check_size
                 DEPENDS gen_project_binary
@@ -56,6 +56,7 @@ consist of two ota app without factory or test partitions.")
                 PARTITION_TYPE app)
             add_dependencies(app app_check_size)
         endif()
+    endif()
 endif()  # NOT BOOTLOADER_BUILD
 
 if(BOOTLOADER_BUILD)

components/esptool_py/Kconfig.projbuild

@@ -1,4 +1,5 @@
 menu "Serial flasher config"
+    depends on !APP_BUILD_TYPE_PURE_RAM_APP
 
     config ESPTOOLPY_NO_STUB
         bool "Disable download stub"

components/esptool_py/project_include.cmake

@@ -19,7 +19,9 @@ set(ESPTOOLPY ${python} "$ENV{ESPTOOL_WRAPPER}" "${CMAKE_CURRENT_LIST_DIR}/espto
 set(ESPSECUREPY ${python} "${CMAKE_CURRENT_LIST_DIR}/esptool/espsecure.py")
 set(ESPEFUSEPY ${python} "${CMAKE_CURRENT_LIST_DIR}/esptool/espefuse.py")
 set(ESPMONITOR ${python} "${idf_path}/tools/idf_monitor.py")
+set(ESPTOOLPY_CHIP "${chip_model}")
 
+if(NOT CONFIG_APP_BUILD_TYPE_RAM AND CONFIG_APP_BUILD_GENERATE_BINARIES)
     if(CONFIG_SPI_FLASH_HPM_ENABLE)
     # When set flash frequency to 120M, must keep 1st bootloader work under ``DOUT`` mode
     # because on some flash chips, 120M will modify the status register,
@@ -34,7 +36,6 @@ endif()
     set(ESPFLASHFREQ ${CONFIG_ESPTOOLPY_FLASHFREQ})
     set(ESPFLASHSIZE ${CONFIG_ESPTOOLPY_FLASHSIZE})
 
-set(ESPTOOLPY_CHIP "${chip_model}")
 
     set(esptool_elf2image_args
         --flash_mode ${ESPFLASHMODE}
@@ -74,6 +75,22 @@ if(NOT CONFIG_SECURE_BOOT_ALLOW_SHORT_APP_PARTITION AND
         endif()
     endif()
 
+    if(CONFIG_ESPTOOLPY_HEADER_FLASHSIZE_UPDATE)
+        # Set ESPFLASHSIZE to 'detect' *after* esptool_elf2image_args are generated,
+        # as elf2image can't have 'detect' as an option...
+        set(ESPFLASHSIZE detect)
+
+        # Flash size detection updates the image header which would invalidate the appended
+        # SHA256 digest. Therefore, a digest is not appended in that case.
+        # This argument requires esptool>=4.1.
+        list(APPEND esptool_elf2image_args --dont-append-digest)
+    endif()
+
+    if(CONFIG_SECURE_SIGNED_APPS_RSA_SCHEME)
+        set(ESPFLASHSIZE keep)
+    endif()
+endif()
+
 # We still set "--min-rev" to keep the app compatible with older booloaders where this field is controlled.
 if(CONFIG_IDF_TARGET_ESP32)
     # for this chip min_rev is major revision
@@ -482,7 +499,11 @@ function(esptool_py_custom_target target_name flasher_filename dependencies)
 endfunction()
 
 if(NOT BOOTLOADER_BUILD)
-    set(flash_deps "partition_table_bin")
+    set(flash_deps "")
+
+    if(CONFIG_APP_BUILD_TYPE_APP_2NDBOOT)
+        list(APPEND flash_deps "partition_table_bin")
+    endif()
 
     if(CONFIG_APP_BUILD_GENERATE_BINARIES)
         list(APPEND flash_deps "app")

components/partition_table/CMakeLists.txt

@@ -144,7 +144,7 @@ endif()
 idf_component_get_property(main_args esptool_py FLASH_ARGS)
 idf_component_get_property(sub_args esptool_py FLASH_SUB_ARGS)
 
-if(CONFIG_APP_BUILD_GENERATE_BINARIES)
+if(CONFIG_APP_BUILD_GENERATE_BINARIES AND CONFIG_APP_BUILD_TYPE_APP_2NDBOOT)
     esptool_py_flash_target(partition-table-flash "${main_args}" "${sub_args}")
     esptool_py_flash_target_image(partition-table-flash partition-table "${PARTITION_TABLE_OFFSET}"
                                         "${build_dir}/partition_table/${final_partition_bin}")

sdkconfig.rename

@@ -23,3 +23,4 @@ CONFIG_WARN_WRITE_STRINGS                     CONFIG_COMPILER_WARN_WRITE_STRINGS
 CONFIG_NO_BLOBS                               CONFIG_APP_NO_BLOBS
 CONFIG_ESP32_COMPATIBLE_PRE_V2_1_BOOTLOADERS  CONFIG_APP_COMPATIBLE_PRE_V2_1_BOOTLOADERS
 CONFIG_ESP32_COMPATIBLE_PRE_V3_1_BOOTLOADERS  CONFIG_APP_COMPATIBLE_PRE_V3_1_BOOTLOADERS
+CONFIG_APP_BUILD_TYPE_ELF_RAM                 CONFIG_APP_BUILD_TYPE_RAM

tools/ci/test_build_system_cmake.sh

@@ -885,7 +885,7 @@ endmenu\n" >> ${IDF_PATH}/Kconfig
     rm -rf build sdkconfig
 
     print_status "Loadable ELF build works"
-    echo "CONFIG_APP_BUILD_TYPE_ELF_RAM=y" > sdkconfig
+    echo "CONFIG_APP_BUILD_TYPE_RAM=y" > sdkconfig
 
     # Set recommend configs to reduce memory footprint
     echo "CONFIG_VFS_SUPPORT_TERMIOS=n" >> sdkconfig

tools/cmake/project.cmake

@@ -153,6 +153,12 @@ function(__project_info test_components)
     idf_build_get_property(COMPONENT_KCONFIGS_PROJBUILD KCONFIG_PROJBUILDS)
     idf_build_get_property(debug_prefix_map_gdbinit DEBUG_PREFIX_MAP_GDBINIT)
 
+    if(CONFIG_APP_BUILD_TYPE_RAM)
+        set(PROJECT_BUILD_TYPE ram_app)
+    else()
+        set(PROJECT_BUILD_TYPE flash_app)
+    endif()
+
     # Write project description JSON file
     idf_build_get_property(build_dir BUILD_DIR)
     make_json_list("${build_components};${test_components}" build_components_json)

tools/cmake/project_description.json.in

@@ -7,6 +7,7 @@
     "bootloader_elf":     "${BOOTLOADER_ELF_FILE}",
     "app_elf":            "${PROJECT_EXECUTABLE}",
     "app_bin":            "${PROJECT_BIN}",
+    "build_type":         "${PROJECT_BUILD_TYPE}",
     "git_revision":       "${IDF_VER}",
     "target":             "${CONFIG_IDF_TARGET}",
     "rev":                "${CONFIG_ESP32_REV_MIN}",

tools/test_apps/system/gdb_loadable_elf/sdkconfig.defaults

@@ -1,4 +1,4 @@
-CONFIG_APP_BUILD_TYPE_ELF_RAM=y
+CONFIG_APP_BUILD_TYPE_RAM=y
 CONFIG_VFS_SUPPORT_TERMIOS=n
 CONFIG_NEWLIB_NANO_FORMAT=y
 CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y