Remove SDK project duplication

Project is created from a single default
Settings are assembled from multiple files

Sming/Arch/Esp32/Components/esp32/.gitignore

@@ -1,3 +1 @@
-sdkconfig
-sdkconfig.defaults
-sdkconfig.old
+project

Sming/Arch/Esp32/Components/esp32/README.rst

@@ -21,23 +21,6 @@ Followed by::
 Configuration variables
 -----------------------
 
-These are read-only debug variables:
-
-.. envvar:: SDK_INTERNAL
-
-   **READONLY** When compiled using the current (version 3+) Espressif SDK this value is set to 1.
-
-
-.. envvar:: SDK_LIBDIR
-
-   **READONLY** Path to the directory containing SDK archive libraries
-
-
-.. envvar:: SDK_INCDIR
-
-   **READONLY** Path to the directory containing SDK header files
-
-
 Option variables:
 
 .. envvar:: ESP_VARIANT
@@ -68,3 +51,19 @@ or if multiple versions are installed. By default, the most current version will
 
    Location of ESP-IDF python.
 
+
+Background
+----------
+
+An empty ESP IDF project is built which generates a set of libraries and headers
+which the framework can then be built against.
+
+The project is located in ``project/{ESP_VARIANT}`.
+
+The code for this project is copied from ``sdk/project``.
+
+The default configuration settings are obtained from ``sdk/config`` and written
+to ``project/{ESP_VARIANT}/sdkconfig.defaults``.
+
+When ``sdk-menuconfig`` is run, the ``project/{ESP_VARIANT}/sdkconfig`` is modified.
+This can be reset using ``make sdk-menuconfig-clean``.

Sming/Arch/Esp32/Components/esp32/component.mk

@@ -13,8 +13,8 @@ SDK_FULL_BUILD ?= 0
 
 COMPONENT_RELINK_VARS += DISABLE_NETWORK DISABLE_WIFI
 
-SDK_BUILD_BASE := $(COMPONENT_BUILD_BASE)/sdk.$(ESP_VARIANT)
-SDK_COMPONENT_LIBDIR := $(COMPONENT_BUILD_BASE)/lib.$(ESP_VARIANT)
+SDK_BUILD_BASE := $(COMPONENT_BUILD_BASE)/$(ESP_VARIANT)/sdk
+SDK_COMPONENT_LIBDIR := $(COMPONENT_BUILD_BASE)/$(ESP_VARIANT)/lib
 
 SDKCONFIG_H := $(SDK_BUILD_BASE)/config/sdkconfig.h
 
@@ -314,7 +314,7 @@ SDK_PARTITION_PATH := $(SDK_DEFAULT_PATH)/partitions
 
 ##@SDK
 
-SDK_PROJECT_PATH := $(COMPONENT_PATH)/project.$(ESP_VARIANT)
+SDK_PROJECT_PATH := $(COMPONENT_PATH)/project/$(ESP_VARIANT)
 SDK_CONFIG_DEFAULTS := $(SDK_PROJECT_PATH)/sdkconfig.defaults
 
 SDKCONFIG_MAKEFILE := $(SDK_PROJECT_PATH)/sdkconfig
@@ -333,7 +333,7 @@ SDK_BUILD_COMPLETE := $(SDK_BUILD_BASE)/.complete
 CUSTOM_TARGETS += checksdk
 
 .PHONY: checksdk
-checksdk: $(SDK_BUILD_COMPLETE)
+checksdk: $(SDK_PROJECT_PATH) $(SDK_BUILD_COMPLETE)
 
 SDK_BUILD = $(ESP32_PYTHON) $(IDF_PATH)/tools/idf.py -C $(SDK_PROJECT_PATH) -B $(SDK_BUILD_BASE) -G Ninja
 
@@ -348,12 +348,20 @@ $(SDK_BUILD_COMPLETE): $(SDKCONFIG_H) $(SDKCONFIG_MAKEFILE)
 	$(Q) $(MAKE) --no-print-directory -C $(SDK_DEFAULT_PATH) -f misc.mk copylibs
 	touch $(SDK_BUILD_COMPLETE)
 
-$(SDKCONFIG_H) $(SDKCONFIG_MAKEFILE) $(SDK_COMPONENT_LIBS): $(SDK_CONFIG_DEFAULTS) | $(SDK_BUILD_BASE) $(SDK_COMPONENT_LIBDIR)
+$(SDKCONFIG_H) $(SDKCONFIG_MAKEFILE) $(SDK_COMPONENT_LIBS): $(SDK_PROJECT_PATH) $(SDK_CONFIG_DEFAULTS) | $(SDK_BUILD_BASE) $(SDK_COMPONENT_LIBDIR)
+
+$(SDK_PROJECT_PATH):
+	$(Q) mkdir -p $@
+	$(Q) cp -r $(SDK_DEFAULT_PATH)/project/* $@
 
 $(SDK_COMPONENT_LIBS): $(SDK_BUILD_COMPLETE)
 
+SDK_CONFIG_FILES := common $(BUILD_TYPE) $(ESP_VARIANT).common $(ESP_VARIANT).$(BUILD_TYPE)
+
 $(SDK_CONFIG_DEFAULTS):
-	$(Q) cp $@.$(BUILD_TYPE) $@
+	$(foreach f,$(addprefix $(SDK_DEFAULT_PATH)/config/,$(SDK_CONFIG_FILES)),\
+		$(if $(wildcard $f),cat $f >> $@;) \
+	)
 
 PHONY: sdk-menuconfig
 sdk-menuconfig: $(SDK_CONFIG_DEFAULTS) | $(SDK_BUILD_BASE) ##Configure SDK options