From bf64c3313d7569160754cbcec7570991eb6b0b95 Mon Sep 17 00:00:00 2001
From: Nedko Arnaudov <nedko@arnaudov.name>
Date: Fri, 22 Jun 2018 04:09:49 +0300
Subject: [PATCH] Import GNU make build system from esp-idf v3

build system is going to be adopted to apeos
---
 make/common.mk            |  88 ++++++++
 make/component_common.mk  |   1 +
 make/component_wrapper.mk | 327 +++++++++++++++++++++++++++
 make/project.mk           | 549 ++++++++++++++++++++++++++++++++++++++++++++++
 make/project_config.mk    |  97 ++++++++
 5 files changed, 1062 insertions(+)
 create mode 100644 make/common.mk
 create mode 100644 make/component_common.mk
 create mode 100644 make/component_wrapper.mk
 create mode 100644 make/project.mk
 create mode 100644 make/project_config.mk

diff --git a/make/common.mk b/make/common.mk
new file mode 100644
index 0000000..ccee322
--- /dev/null
+++ b/make/common.mk
@@ -0,0 +1,88 @@
+# Functionality common to both top-level project makefile (project.mk)
+# and component makefiles (component_wrapper.mk)
+#
+
+# Include project config makefile, if it exists.
+#
+# (Note that we only rebuild this makefile automatically for some
+# targets, see project_config.mk for details.)
+SDKCONFIG_MAKEFILE ?= $(abspath $(BUILD_DIR_BASE)/include/config/auto.conf)
+-include $(SDKCONFIG_MAKEFILE)
+export SDKCONFIG_MAKEFILE  # sub-makes (like bootloader) will reuse this path
+
+# BATCH_BUILD flag disables interactive terminal features, defaults to verbose build
+ifdef BATCH_BUILD
+V ?= 1
+endif
+
+#Handling of V=1/VERBOSE=1 flag
+#
+# if V=1, $(summary) does nothing and $(details) will echo extra details
+# if V is unset or not 1, $(summary) echoes a summary and $(details) does nothing
+VERBOSE ?=
+V ?= $(VERBOSE)
+ifeq ("$(V)","1")
+summary := @true
+details := @echo
+else
+summary := @echo
+details := @true
+
+# disable echoing of commands, directory names
+MAKEFLAGS += --silent
+endif  # $(V)==1
+
+ifdef CONFIG_MAKE_WARN_UNDEFINED_VARIABLES
+MAKEFLAGS += --warn-undefined-variables
+endif
+
+# General make utilities
+
+# convenience variable for printing an 80 asterisk wide separator line
+SEPARATOR:="*******************************************************************************"
+
+# macro to remove quotes from an argument, ie $(call dequote,$(CONFIG_BLAH))
+define dequote
+$(subst ",,$(1))
+endef
+# " comment kept here to keep syntax highlighting happy
+
+
+# macro to keep an absolute path as-is, but resolve a relative path
+# against a particular parent directory
+#
+# $(1) path to resolve
+# $(2) directory to resolve non-absolute path against
+#
+# Path and directory don't have to exist (definition of a "relative
+# path" is one that doesn't start with /)
+#
+# $(2) can contain a trailing forward slash or not, result will not
+# double any path slashes.
+#
+# example $(call resolvepath,$(CONFIG_PATH),$(CONFIG_DIR))
+define resolvepath
+$(foreach dir,$(1),$(if $(filter /%,$(dir)),$(dir),$(subst //,/,$(2)/$(dir))))
+endef
+
+
+# macro to include a target only if it's on the list of targets that make
+# was invoked with
+#
+# This allows you to have something like an "order-only phony prerequisite",
+# ie a prerequisite that determines an order phony targets have to run in.
+#
+# Because normal order-only prerequisites don't work with phony targets.
+#
+# example $(call prereq_if_explicit,erase_flash)
+define prereq_if_explicit
+$(filter $(1),$(MAKECMDGOALS))
+endef
+
+# macro to kill duplicate items in a list without messing up the sort order of the list.
+# Will only keep the unique items; if there are non-unique items in the list, it will remove
+# the later recurring ones so only the first one remains.
+# Copied from http://stackoverflow.com/questions/16144115/makefile-remove-duplicate-words-without-sorting
+define uniq
+$(if $1,$(firstword $1) $(call uniq,$(filter-out $(firstword $1),$1)))
+endef
diff --git a/make/component_common.mk b/make/component_common.mk
new file mode 100644
index 0000000..187e1ed
--- /dev/null
+++ b/make/component_common.mk
@@ -0,0 +1 @@
+$(warning Deprecated feature: No longer necessary to include component_common.mk from $(COMPONENT_PATH)/component.mk)
diff --git a/make/component_wrapper.mk b/make/component_wrapper.mk
new file mode 100644
index 0000000..e43e82a
--- /dev/null
+++ b/make/component_wrapper.mk
@@ -0,0 +1,327 @@
+# Component wrapper makefile
+#
+# This makefile gets called recursively from the project make, once for each component.
+# COMPONENT_MAKEFILE is set to point at the component.mk file for the component itself,
+# which is included as part of this process (after default variables are defined).
+#
+# This makefile comprises multiple stages, marked in blocked comments below.
+#
+# CWD is the build directory of the component.
+
+ifndef PROJECT_PATH
+$(error Make was invoked from $(CURDIR). However please do not run make from the sdk or a component directory; invoke make from the project directory. See the ESP-IDF README for details.)
+endif
+
+
+################################################################################
+# 1) Set default variables for the component build (including configuration
+#	loaded from sdkconfig.)
+################################################################################
+
+# Find the path to the component
+COMPONENT_PATH := $(abspath $(dir $(COMPONENT_MAKEFILE)))
+export COMPONENT_PATH
+
+# COMPONENT_BUILD_DIR is otherwise known as CWD for the build
+COMPONENT_BUILD_DIR := $(abspath .)
+
+# include elements common to both project & component makefiles
+# (includes project configuration set via menuconfig)
+include $(IDF_PATH)/make/common.mk
+
+# Some of the following defaults may be overriden by the component's component.mk makefile,
+# during the next step:
+
+# Absolute path of the .a file
+COMPONENT_LIBRARY = lib$(COMPONENT_NAME).a
+
+# Source dirs a component has. Default to root directory of component.
+COMPONENT_SRCDIRS = .
+
+#Names of binary & text files to embed as raw content in the component library
+COMPONENT_EMBED_FILES ?=
+COMPONENT_EMBED_TXTFILES ?=
+
+# By default, include only the include/ dir.
+COMPONENT_ADD_INCLUDEDIRS = include
+COMPONENT_ADD_LDFLAGS = -l$(COMPONENT_NAME)
+
+# Define optional compiling macros
+define compile_exclude 
+COMPONENT_OBJEXCLUDE += $(1)
+endef
+
+define compile_include
+COMPONENT_OBJINCLUDE += $(1)
+endef
+
+define compile_only_if
+$(eval $(if $(1), $(call compile_include, $(2)), $(call compile_exclude, $(2))))
+endef
+
+define compile_only_if_not 
+$(eval $(if $(1), $(call compile_exclude, $(2)), $(call compile_include, $(2))))
+endef
+
+COMPONENT_ADD_LINKER_DEPS ?=
+COMPONENT_DEPENDS ?=
+COMPONENT_EXTRA_CLEAN ?=
+COMPONENT_EXTRA_INCLUDES ?=
+COMPONENT_OBJEXCLUDE ?=
+COMPONENT_OBJINCLUDE ?=
+COMPONENT_SUBMODULES ?=
+
+################################################################################
+# 2) Include the component.mk for the specific component (COMPONENT_MAKEFILE) to
+#     override variables & optionally define custom targets. Also include global
+#     component makefiles.
+################################################################################
+
+
+# Include any Makefile.componentbuild file letting components add
+# configuration at the global component level
+
+# Save component_path; we pass it to the called Makefile.componentbuild
+# as COMPILING_COMPONENT_PATH, and we use it to restore the current 
+# COMPONENT_PATH later.
+COMPILING_COMPONENT_PATH := $(COMPONENT_PATH)
+
+define includeCompBuildMakefile
+$(if $(V),$(info including $(1)/Makefile.componentbuild...))
+COMPONENT_PATH := $(1)
+include $(1)/Makefile.componentbuild
+endef
+$(foreach componentpath,$(COMPONENT_PATHS), \
+	$(if $(wildcard $(componentpath)/Makefile.componentbuild), \
+		$(eval $(call includeCompBuildMakefile,$(componentpath)))))
+
+#Restore COMPONENT_PATH to what it was
+COMPONENT_PATH := $(COMPILING_COMPONENT_PATH)
+
+
+# Include component.mk for this component.
+include $(COMPONENT_MAKEFILE)
+
+
+################################################################################
+# 3) Set variables that depend on values that may changed by component.mk
+################################################################################
+
+ifndef COMPONENT_CONFIG_ONLY  # Skip steps 3-5 if COMPONENT_CONFIG_ONLY is set
+
+# Object files which need to be linked into the library
+# By default we take all .c, .cpp, .cc & .S files in COMPONENT_SRCDIRS.
+ifndef COMPONENT_OBJS
+# Find all source files in all COMPONENT_SRCDIRS
+COMPONENT_OBJS := $(foreach compsrcdir,$(COMPONENT_SRCDIRS),$(patsubst %.c,%.o,$(wildcard $(COMPONENT_PATH)/$(compsrcdir)/*.c)))
+COMPONENT_OBJS += $(foreach compsrcdir,$(COMPONENT_SRCDIRS),$(patsubst %.cpp,%.o,$(wildcard $(COMPONENT_PATH)/$(compsrcdir)/*.cpp)))
+COMPONENT_OBJS += $(foreach compsrcdir,$(COMPONENT_SRCDIRS),$(patsubst %.cc,%.o,$(wildcard $(COMPONENT_PATH)/$(compsrcdir)/*.cc)))
+COMPONENT_OBJS += $(foreach compsrcdir,$(COMPONENT_SRCDIRS),$(patsubst %.S,%.o,$(wildcard $(COMPONENT_PATH)/$(compsrcdir)/*.S)))
+# Make relative by removing COMPONENT_PATH from all found object paths
+COMPONENT_OBJS := $(patsubst $(COMPONENT_PATH)/%,%,$(COMPONENT_OBJS))
+else
+# Add in components defined by conditional compiling macros
+COMPONENT_OBJS += $(COMPONENT_OBJINCLUDE)
+endif
+# Remove items disabled by optional compilation
+COMPONENT_OBJS := $(foreach obj,$(COMPONENT_OBJS),$(if $(filter $(realpath $(obj)),$(realpath $(COMPONENT_OBJEXCLUDE))), ,$(obj)))
+
+# Remove duplicates
+COMPONENT_OBJS := $(call uniq,$(COMPONENT_OBJS))
+
+
+# Object files with embedded binaries to add to the component library
+# Correspond to the files named in COMPONENT_EMBED_FILES & COMPONENT_EMBED_TXTFILES
+COMPONENT_EMBED_OBJS ?= $(addsuffix .bin.o,$(notdir $(COMPONENT_EMBED_FILES))) $(addsuffix .txt.o,$(notdir $(COMPONENT_EMBED_TXTFILES)))
+
+# If we're called to compile something, we'll get passed the COMPONENT_INCLUDES
+# variable with all the include dirs from all the components in random order. This
+# means we can accidentally grab a header from another component before grabbing our own.
+# To make sure that does not happen, re-order the includes so ours come first.
+COMPONENT_PRIV_INCLUDEDIRS ?=
+OWN_INCLUDES:=$(abspath $(addprefix $(COMPONENT_PATH)/,$(COMPONENT_PRIV_INCLUDEDIRS) $(COMPONENT_ADD_INCLUDEDIRS)))
+COMPONENT_INCLUDES := $(OWN_INCLUDES) $(filter-out $(OWN_INCLUDES),$(COMPONENT_INCLUDES))
+
+
+################################################################################
+# 4) Define a target to generate component_project_vars.mk Makefile which
+# contains common per-component settings which are included directly in the
+# top-level project make
+#
+# (Skipped if COMPONENT_CONFIG_ONLY is set.)
+################################################################################
+
+# macro to generate variable-relative paths inside component_project_vars.mk, whenever possible
+# ie put literal $(IDF_PATH), $(PROJECT_PATH) and $(BUILD_DIR_BASE) into the generated
+# makefiles where possible.
+#
+# This means if directories move (breaking absolute paths), don't need to 'make clean'
+define MakeVariablePath
+$(subst $(IDF_PATH),$$(IDF_PATH),$(subst $(PROJECT_PATH),$$(PROJECT_PATH),$(subst $(BUILD_DIR_BASE),$$(BUILD_DIR_BASE),$(1))))
+endef
+
+# component_project_vars.mk target for the component. This is used to
+# take component.mk variables COMPONENT_ADD_INCLUDEDIRS,
+# COMPONENT_ADD_LDFLAGS, COMPONENT_DEPENDS and COMPONENT_SUBMODULES
+# and inject those into the project make pass.
+#
+# The target here has no dependencies, as the parent target in
+# project.mk evaluates dependencies before calling down to here. See
+# GenerateComponentTargets macro in project.mk.
+#
+# If you are thinking of editing the output of this target for a
+# component-specific feature, please don't! What you want is a
+# Makefile.projbuild for your component (see docs/build-system.rst for
+# more.)
+#
+# Note: The :: target here is not a mistake. This target should always be
+# executed, as dependencies are checked by the parent project-level make target.
+# See https://www.gnu.org/software/make/manual/make.html#index-_003a_003a-rules-_0028double_002dcolon_0029
+component_project_vars.mk::
+	$(details) "Building component project variables list $(abspath $@)"
+	@echo '# Automatically generated build file. Do not edit.' > $@
+	@echo 'COMPONENT_INCLUDES += $(call MakeVariablePath,$(addprefix $(COMPONENT_PATH)/,$(COMPONENT_ADD_INCLUDEDIRS)))' >> $@
+	@echo 'COMPONENT_LDFLAGS += $(call MakeVariablePath,-L$(COMPONENT_BUILD_DIR) $(COMPONENT_ADD_LDFLAGS))' >> $@
+	@echo 'COMPONENT_LINKER_DEPS += $(call MakeVariablePath,$(call resolvepath,$(COMPONENT_ADD_LINKER_DEPS),$(COMPONENT_PATH)))' >> $@
+	@echo 'COMPONENT_SUBMODULES += $(call MakeVariablePath,$(addprefix $(COMPONENT_PATH)/,$(COMPONENT_SUBMODULES)))' >> $@
+	@echo 'COMPONENT_LIBRARIES += $(COMPONENT_NAME)' >> $@
+	@echo 'component-$(COMPONENT_NAME)-build: $(addprefix component-,$(addsuffix -build,$(COMPONENT_DEPENDS)))' >> $@
+
+################################################################################
+# 5) Where COMPONENT_OWNBUILDTARGET / COMPONENT_OWNCLEANTARGET
+# is not set by component.mk, define default build, clean, etc. targets
+#
+# (Skipped if COMPONENT_CONFIG_ONLY is set.)
+################################################################################
+
+# Default build behaviour: define a phony build target and a COMPONENT_LIBRARY link target.
+ifndef COMPONENT_OWNBUILDTARGET
+.PHONY: build
+build: $(COMPONENT_LIBRARY)
+
+# Build the archive. We remove the archive first, otherwise ar will get confused if we update
+# an archive when multiple filenames have the same name (src1/test.o and src2/test.o)
+$(COMPONENT_LIBRARY): $(COMPONENT_OBJS) $(COMPONENT_EMBED_OBJS)
+	$(summary) AR $(patsubst $(PWD)/%,%,$(CURDIR))/$@
+	rm -f $@
+	$(AR) cru $@ $^
+endif
+
+# If COMPONENT_OWNCLEANTARGET is not set, define a phony clean target
+ifndef COMPONENT_OWNCLEANTARGET
+CLEAN_FILES := $(COMPONENT_LIBRARY) $(COMPONENT_OBJS) $(COMPONENT_OBJS:.o=.d) $(COMPONENT_OBJEXCLUDE) $(COMPONENT_OBJEXCLUDE:.o=.d) $(COMPONENT_EMBED_OBJS) $(COMPONENT_EXTRA_CLEAN) component_project_vars.mk
+.PHONY: clean
+clean:
+	$(summary) RM $(CLEAN_FILES)
+	rm -f $(CLEAN_FILES)
+endif
+
+DEBUG_FLAGS ?= -ggdb
+
+# Include all dependency files already generated
+-include $(COMPONENT_OBJS:.o=.d)
+
+# This is a fix for situation where the project or IDF dir moves, and instead
+# of rebuilding the target the build fails until make clean is run
+#
+# It adds an empty dependency rule for the (possibly non-existent) source file itself,
+# which prevents it not being found from failing the build
+#
+# $1 == Source File, $2 == .o file used for .d file name
+define AppendSourceToDependencies
+echo "$1:" >> $$(patsubst %.o,%.d,$2)
+endef
+
+
+# This pattern is generated for each COMPONENT_SRCDIR to compile the files in it.
+define GenerateCompileTargets
+# $(1) - directory containing source files, relative to $(COMPONENT_PATH) - one of $(COMPONENT_SRCDIRS)
+#
+$(1)/%.o: $$(COMPONENT_PATH)/$(1)/%.c $(COMMON_MAKEFILES) $(COMPONENT_MAKEFILE) | $(COMPONENT_SRCDIRS)
+	$$(summary) CC $$(patsubst $$(PWD)/%,%,$$(CURDIR))/$$@
+	$$(CC) $$(CFLAGS) $$(CPPFLAGS) $$(addprefix -I ,$$(COMPONENT_INCLUDES)) $$(addprefix -I ,$$(COMPONENT_EXTRA_INCLUDES)) -I$(1) -c $$< -o $$@
+	$(call AppendSourceToDependencies,$$<,$$@)
+
+$(1)/%.o: $$(COMPONENT_PATH)/$(1)/%.cpp $(COMMON_MAKEFILES) $(COMPONENT_MAKEFILE) | $(COMPONENT_SRCDIRS)
+	$$(summary) CXX $$(patsubst $$(PWD)/%,%,$$(CURDIR))/$$@
+	$$(CXX) $$(CXXFLAGS) $$(CPPFLAGS) $$(addprefix -I,$$(COMPONENT_INCLUDES)) $$(addprefix -I,$$(COMPONENT_EXTRA_INCLUDES)) -I$(1) -c $$< -o $$@
+	$(call AppendSourceToDependencies,$$<,$$@)
+
+$(1)/%.o: $$(COMPONENT_PATH)/$(1)/%.cc $(COMMON_MAKEFILES) $(COMPONENT_MAKEFILE) | $(COMPONENT_SRCDIRS)
+	$$(summary) CXX $$(patsubst $$(PWD)/%,%,$$(CURDIR))/$$@
+	$$(CXX) $$(CXXFLAGS) $$(CPPFLAGS) $$(addprefix -I,$$(COMPONENT_INCLUDES)) $$(addprefix -I,$$(COMPONENT_EXTRA_INCLUDES)) -I$(1) -c $$< -o $$@
+	$(call AppendSourceToDependencies,$$<,$$@)
+
+$(1)/%.o: $$(COMPONENT_PATH)/$(1)/%.S $(COMMON_MAKEFILES) $(COMPONENT_MAKEFILE) | $(COMPONENT_SRCDIRS)
+	$$(summary) AS $$(patsubst $$(PWD)/%,%,$$(CURDIR))/$$@
+	$$(CC) $$(CPPFLAGS) $$(DEBUG_FLAGS) $$(addprefix -I ,$$(COMPONENT_INCLUDES)) $$(addprefix -I ,$$(COMPONENT_EXTRA_INCLUDES)) -I$(1) -c $$< -o $$@
+	$(call AppendSourceToDependencies,$$<,$$@)
+
+# CWD is build dir, create the build subdirectory if it doesn't exist
+#
+# (NB: Each .o file depends on all relative component build dirs $(COMPONENT_SRCDIRS), rather than just $(1), to work
+# around a behaviour make 3.81 where the first pattern (randomly) seems to be matched rather than the best fit. ie if
+# you have objects a/y.o and a/b/c.o then c.o can be matched with $(1)=a & %=b/c, meaning that subdir 'a/b' needs to be
+# created but wouldn't be created if $(1)=a. Make 4.x doesn't have this problem, it seems to preferentially
+# choose the better match ie $(1)=a/b and %=c )
+#
+$(1):
+	mkdir -p $(1)
+endef
+
+# Generate all the compile target patterns
+$(foreach srcdir,$(COMPONENT_SRCDIRS), $(eval $(call GenerateCompileTargets,$(srcdir))))
+
+## Support for embedding binary files into the ELF as symbols
+
+OBJCOPY_EMBED_ARGS := --input-target binary --output-target elf32-xtensa-le --binary-architecture xtensa --rename-section .data=.rodata.embedded
+
+# Generate pattern for embedding text or binary files into the app
+# $(1) is name of file (as relative path inside component)
+# $(2) is txt or bin depending on file contents
+#
+# txt files are null-terminated before being embedded (otherwise
+# identical behaviour.)
+#
+define GenerateEmbedTarget
+
+# copy the input file into the build dir (using a subdirectory
+# in case the file already exists elsewhere in the build dir)
+embed_bin/$$(notdir $(1)): $(call resolvepath,$(1),$(COMPONENT_PATH)) | embed_bin
+	cp $$< $$@
+
+embed_txt/$$(notdir $(1)): $(call resolvepath,$(1),$(COMPONENT_PATH)) | embed_txt
+	cp $$< $$@
+	printf '\0' >> $$@  # null-terminate text files
+
+# messing about with the embed_X subdirectory then using 'cd' for objcopy is because the
+# full path passed to OBJCOPY makes it into the name of the symbols in the .o file
+$$(notdir $(1)).$(2).o: embed_$(2)/$$(notdir $(1))
+	$(summary) EMBED $$(patsubst $$(PWD)/%,%,$$(CURDIR))/$$@
+	cd embed_$(2); $(OBJCOPY) $(OBJCOPY_EMBED_ARGS) $$(notdir $$<) ../$$@
+
+CLEAN_FILES += embed_$(2)/$$(notdir $(1))
+endef
+
+embed_txt embed_bin:
+	mkdir -p $@
+
+# generate targets to embed binary & text files
+$(foreach binfile,$(COMPONENT_EMBED_FILES), $(eval $(call GenerateEmbedTarget,$(binfile),bin)))
+
+$(foreach txtfile,$(COMPONENT_EMBED_TXTFILES), $(eval $(call GenerateEmbedTarget,$(txtfile),txt)))
+
+else   # COMPONENT_CONFIG_ONLY is set
+
+build:
+	$(details) "No build needed for $(COMPONENT_NAME) (COMPONENT_CONFIG_ONLY)"
+
+clean:
+	$(summary) RM component_project_vars.mk
+	rm -f component_project_vars.mk
+
+component_project_vars.mk::  # no need to add variables via component.mk
+	@echo '# COMPONENT_CONFIG_ONLY target sets no variables here' > $@
+
+endif  # COMPONENT_CONFIG_ONLY
+
diff --git a/make/project.mk b/make/project.mk
new file mode 100644
index 0000000..31f72bc
--- /dev/null
+++ b/make/project.mk
@@ -0,0 +1,549 @@
+#
+# Main Project Makefile
+# This Makefile is included directly from the user project Makefile in order to call the component.mk
+# makefiles of all components (in a separate make process) to build all the libraries, then links them
+# together into the final file. If so, PWD is the project dir (we assume).
+#
+
+#
+# This makefile requires the environment variable IDF_PATH to be set to the top-level esp-idf directory
+# where this file is located.
+#
+
+.PHONY: build-components menuconfig defconfig all build clean all_binaries check-submodules size size-components size-files list-components
+
+MAKECMDGOALS ?= all
+all: all_binaries
+# see below for recipe of 'all' target
+#
+# # other components will add dependencies to 'all_binaries'. The
+# reason all_binaries is used instead of 'all' is so that the flash
+# target can build everything without triggering the per-component "to
+# flash..." output targets.)
+
+help:
+	@echo "Welcome to Espressif IDF build system. Some useful make targets:"
+	@echo ""
+	@echo "make menuconfig - Configure IDF project"
+	@echo "make defconfig - Set defaults for all new configuration options"
+	@echo ""
+	@echo "make all - Build app, bootloader, partition table"
+	@echo "make flash - Flash app, bootloader, partition table to a chip"
+	@echo "make clean - Remove all build output"
+	@echo "make size - Display the static memory footprint of the app"
+	@echo "make size-components, size-files - Finer-grained memory footprints"
+	@echo "make erase_flash - Erase entire flash contents"
+	@echo "make monitor - Run idf_monitor tool to monitor serial output from app"
+	@echo "make simple_monitor - Monitor serial output on terminal console"
+	@echo "make list-components - List all components in the project"
+	@echo ""
+	@echo "make app - Build just the app"
+	@echo "make app-flash - Flash just the app"
+	@echo "make app-clean - Clean just the app"
+	@echo "make print_flash_cmd - Print the arguments for esptool when flash"
+	@echo ""
+	@echo "See also 'make bootloader', 'make bootloader-flash', 'make bootloader-clean', "
+	@echo "'make partition_table', etc, etc."
+
+# dependency checks
+ifndef MAKE_RESTARTS
+ifeq ("$(filter 4.% 3.81 3.82,$(MAKE_VERSION))","")
+$(warning esp-idf build system only supports GNU Make versions 3.81 or newer. You may see unexpected results with other Makes.)
+endif
+
+ifdef MSYSTEM
+ifneq ("$(MSYSTEM)","MINGW32")
+$(warning esp-idf build system only supports MSYS2 in "MINGW32" mode. Consult the ESP-IDF documentation for details.)
+endif
+endif  # MSYSTEM
+
+endif  # MAKE_RESTARTS
+
+# can't run 'clean' along with any non-clean targets
+ifneq ("$(filter clean% %clean,$(MAKECMDGOALS))" ,"")
+ifneq ("$(filter-out clean% %clean,$(MAKECMDGOALS))", "")
+$(error esp-idf build system doesn't support running 'clean' targets along with any others. Run 'make clean' and then run other targets separately.)
+endif
+endif
+
+OS ?=
+
+# make IDF_PATH a "real" absolute path
+# * works around the case where a shell character is embedded in the environment variable value.
+# * changes Windows-style C:/blah/ paths to MSYS style /c/blah
+ifeq ("$(OS)","Windows_NT")
+# On Windows MSYS2, make wildcard function returns empty string for paths of form /xyz
+# where /xyz is a directory inside the MSYS root - so we don't use it.
+SANITISED_IDF_PATH:=$(realpath $(IDF_PATH))
+else
+SANITISED_IDF_PATH:=$(realpath $(wildcard $(IDF_PATH)))
+endif
+
+export IDF_PATH := $(SANITISED_IDF_PATH)
+
+ifndef IDF_PATH
+$(error IDF_PATH variable is not set to a valid directory.)
+endif
+
+ifneq ("$(IDF_PATH)","$(SANITISED_IDF_PATH)")
+# implies IDF_PATH was overriden on make command line.
+# Due to the way make manages variables, this is hard to account for
+#
+# if you see this error, do the shell expansion in the shell ie
+# make IDF_PATH=~/blah not make IDF_PATH="~/blah"
+$(error If IDF_PATH is overriden on command line, it must be an absolute path with no embedded shell special characters)
+endif
+
+ifneq ("$(IDF_PATH)","$(subst :,,$(IDF_PATH))")
+$(error IDF_PATH cannot contain colons. If overriding IDF_PATH on Windows, use MSYS Unix-style /c/dir instead of C:/dir)
+endif
+
+# disable built-in make rules, makes debugging saner
+MAKEFLAGS_OLD := $(MAKEFLAGS)
+MAKEFLAGS +=-rR
+
+# Default path to the project: we assume the Makefile including this file
+# is in the project directory
+ifndef PROJECT_PATH
+PROJECT_PATH := $(abspath $(dir $(firstword $(MAKEFILE_LIST))))
+export PROJECT_PATH
+endif
+
+# A list of the "common" makefiles, to use as a target dependency
+COMMON_MAKEFILES := $(abspath $(IDF_PATH)/make/project.mk $(IDF_PATH)/make/common.mk $(IDF_PATH)/make/component_wrapper.mk $(firstword $(MAKEFILE_LIST)))
+export COMMON_MAKEFILES
+
+# The directory where we put all objects/libraries/binaries. The project Makefile can
+# configure this if needed.
+ifndef BUILD_DIR_BASE
+BUILD_DIR_BASE := $(PROJECT_PATH)/build
+endif
+export BUILD_DIR_BASE
+
+# Component directories. These directories are searched for components (either the directory is a component,
+# or the directory contains subdirectories which are components.)
+# The project Makefile can override these component dirs, or add extras via EXTRA_COMPONENT_DIRS
+ifndef COMPONENT_DIRS
+EXTRA_COMPONENT_DIRS ?=
+COMPONENT_DIRS := $(PROJECT_PATH)/components $(EXTRA_COMPONENT_DIRS) $(IDF_PATH)/components $(PROJECT_PATH)/main
+endif
+export COMPONENT_DIRS
+
+ifdef SRCDIRS
+$(warning SRCDIRS variable is deprecated. These paths can be added to EXTRA_COMPONENT_DIRS or COMPONENT_DIRS instead.)
+COMPONENT_DIRS += $(abspath $(SRCDIRS))
+endif
+
+# The project Makefile can define a list of components, but if it does not do this we just take all available components
+# in the component dirs. A component is COMPONENT_DIRS directory, or immediate subdirectory,
+# which contains a component.mk file.
+#
+# Use the "make list-components" target to debug this step.
+ifndef COMPONENTS
+# Find all component names. The component names are the same as the
+# directories they're in, so /bla/components/mycomponent/component.mk -> mycomponent.
+COMPONENTS := $(dir $(foreach cd,$(COMPONENT_DIRS),                           \
+					$(wildcard $(cd)/*/component.mk) $(wildcard $(cd)/component.mk) \
+				))
+COMPONENTS := $(sort $(foreach comp,$(COMPONENTS),$(lastword $(subst /, ,$(comp)))))
+endif
+export COMPONENTS
+
+# Resolve all of COMPONENTS into absolute paths in COMPONENT_PATHS.
+#
+# If a component name exists in multiple COMPONENT_DIRS, we take the first match.
+#
+# NOTE: These paths must be generated WITHOUT a trailing / so we
+# can use $(notdir x) to get the component name.
+COMPONENT_PATHS := $(foreach comp,$(COMPONENTS),$(firstword $(foreach cd,$(COMPONENT_DIRS),$(wildcard $(dir $(cd))$(comp) $(cd)/$(comp)))))
+export COMPONENT_PATHS
+
+TEST_COMPONENTS ?=
+TESTS_ALL ?=
+
+# If TESTS_ALL set to 1, set TEST_COMPONENTS_LIST to all components.
+# Otherwise, use the list supplied in TEST_COMPONENTS.
+ifeq ($(TESTS_ALL),1)
+TEST_COMPONENTS_LIST := $(COMPONENTS)
+else
+TEST_COMPONENTS_LIST := $(TEST_COMPONENTS)
+endif
+
+TEST_COMPONENT_PATHS := $(foreach comp,$(TEST_COMPONENTS_LIST),$(firstword $(foreach dir,$(COMPONENT_DIRS),$(wildcard $(dir)/$(comp)/test))))
+TEST_COMPONENT_NAMES := $(foreach comp,$(TEST_COMPONENT_PATHS),$(lastword $(subst /, ,$(dir $(comp))))_test)
+
+# Initialise project-wide variables which can be added to by
+# each component.
+#
+# These variables are built up via the component_project_vars.mk
+# generated makefiles (one per component).
+#
+# See docs/build-system.rst for more details.
+COMPONENT_INCLUDES :=
+COMPONENT_LDFLAGS :=
+COMPONENT_SUBMODULES :=
+COMPONENT_LIBRARIES :=
+
+# COMPONENT_PROJECT_VARS is the list of component_project_vars.mk generated makefiles
+# for each component.
+#
+# Including $(COMPONENT_PROJECT_VARS) builds the COMPONENT_INCLUDES,
+# COMPONENT_LDFLAGS variables and also targets for any inter-component
+# dependencies.
+#
+# See the component_project_vars.mk target in component_wrapper.mk
+COMPONENT_PROJECT_VARS := $(addsuffix /component_project_vars.mk,$(notdir $(COMPONENT_PATHS) ) $(TEST_COMPONENT_NAMES))
+COMPONENT_PROJECT_VARS := $(addprefix $(BUILD_DIR_BASE)/,$(COMPONENT_PROJECT_VARS))
+# this line is -include instead of include to prevent a spurious error message on make 3.81
+-include $(COMPONENT_PROJECT_VARS)
+
+# Also add top-level project include path, for top-level includes
+COMPONENT_INCLUDES += $(abspath $(BUILD_DIR_BASE)/include/)
+
+export COMPONENT_INCLUDES
+
+# Set variables common to both project & component
+include $(IDF_PATH)/make/common.mk
+
+all:
+ifdef CONFIG_SECURE_BOOT_ENABLED
+	@echo "(Secure boot enabled, so bootloader not flashed automatically. See 'make bootloader' output)"
+ifndef CONFIG_SECURE_BOOT_BUILD_SIGNED_BINARIES
+	@echo "App built but not signed. Sign app & partition data before flashing, via espsecure.py:"
+	@echo "espsecure.py sign_data --keyfile KEYFILE $(APP_BIN)"
+	@echo "espsecure.py sign_data --keyfile KEYFILE $(PARTITION_TABLE_BIN)"
+endif
+	@echo "To flash app & partition table, run 'make flash' or:"
+else
+	@echo "To flash all build output, run 'make flash' or:"
+endif
+	@echo $(ESPTOOLPY_WRITE_FLASH) $(ESPTOOL_ALL_FLASH_ARGS)
+
+
+IDF_VER := $(shell cd ${IDF_PATH} && git describe --always --tags --dirty)
+
+# Set default LDFLAGS
+EXTRA_LDFLAGS ?=
+LDFLAGS ?= -nostdlib \
+	-u call_user_start_cpu0	\
+	$(EXTRA_LDFLAGS) \
+	-Wl,--gc-sections	\
+	-Wl,-static	\
+	-Wl,--start-group	\
+	$(COMPONENT_LDFLAGS) \
+	-lgcc \
+	-lstdc++ \
+	-lgcov \
+	-Wl,--end-group \
+	-Wl,-EL
+
+# Set default CPPFLAGS, CFLAGS, CXXFLAGS
+# These are exported so that components can use them when compiling.
+# If you need your component to add CFLAGS/etc for it's own source compilation only, set CFLAGS += in your component's Makefile.
+# If you need your component to add CFLAGS/etc globally for all source
+#  files, set CFLAGS += in your component's Makefile.projbuild
+# If you need to set CFLAGS/CPPFLAGS/CXXFLAGS at project level, set them in application Makefile
+#  before including project.mk. Default flags will be added before the ones provided in application Makefile.
+
+# CPPFLAGS used by C preprocessor
+# If any flags are defined in application Makefile, add them at the end. 
+CPPFLAGS ?=
+EXTRA_CPPFLAGS ?=
+CPPFLAGS := -DESP_PLATFORM -D IDF_VER=\"$(IDF_VER)\" -MMD -MP $(CPPFLAGS) $(EXTRA_CPPFLAGS)
+
+# Warnings-related flags relevant both for C and C++
+COMMON_WARNING_FLAGS = -Wall -Werror=all \
+	-Wno-error=unused-function \
+	-Wno-error=unused-but-set-variable \
+	-Wno-error=unused-variable \
+	-Wno-error=deprecated-declarations \
+	-Wextra \
+	-Wno-unused-parameter -Wno-sign-compare
+
+# Flags which control code generation and dependency generation, both for C and C++
+COMMON_FLAGS = \
+	-ffunction-sections -fdata-sections \
+	-fstrict-volatile-bitfields \
+	-mlongcalls \
+	-nostdlib
+
+ifndef IS_BOOTLOADER_BUILD
+# stack protection (only one option can be selected in menuconfig)
+ifdef CONFIG_STACK_CHECK_NORM
+COMMON_FLAGS += -fstack-protector
+endif
+ifdef CONFIG_STACK_CHECK_STRONG
+COMMON_FLAGS += -fstack-protector-strong
+endif
+ifdef CONFIG_STACK_CHECK_ALL
+COMMON_FLAGS += -fstack-protector-all
+endif
+endif
+
+# Optimization flags are set based on menuconfig choice
+ifdef CONFIG_OPTIMIZATION_LEVEL_RELEASE
+OPTIMIZATION_FLAGS = -Os
+else
+OPTIMIZATION_FLAGS = -Og
+endif
+
+ifdef CONFIG_OPTIMIZATION_ASSERTIONS_DISABLED
+CPPFLAGS += -DNDEBUG
+endif
+
+# Enable generation of debugging symbols
+# (we generate even in Release mode, as this has no impact on final binary size.)
+DEBUG_FLAGS ?= -ggdb
+
+# List of flags to pass to C compiler
+# If any flags are defined in application Makefile, add them at the end.
+CFLAGS ?=
+EXTRA_CFLAGS ?=
+CFLAGS := $(strip \
+	-std=gnu99 \
+	$(OPTIMIZATION_FLAGS) $(DEBUG_FLAGS) \
+	$(COMMON_FLAGS) \
+	$(COMMON_WARNING_FLAGS) -Wno-old-style-declaration \
+	$(CFLAGS) \
+	$(EXTRA_CFLAGS))
+
+# List of flags to pass to C++ compiler
+# If any flags are defined in application Makefile, add them at the end.
+CXXFLAGS ?=
+EXTRA_CXXFLAGS ?=
+CXXFLAGS := $(strip \
+	-std=gnu++11 \
+	-fno-rtti \
+	$(OPTIMIZATION_FLAGS) $(DEBUG_FLAGS) \
+	$(COMMON_FLAGS) \
+	$(COMMON_WARNING_FLAGS) \
+	$(CXXFLAGS) \
+	$(EXTRA_CXXFLAGS))
+
+ifdef CONFIG_CXX_EXCEPTIONS
+CXXFLAGS += -fexceptions
+else
+CXXFLAGS += -fno-exceptions
+endif
+
+export CFLAGS CPPFLAGS CXXFLAGS
+
+# Set default values that were not previously defined
+CC ?= gcc
+LD ?= ld
+AR ?= ar
+OBJCOPY ?= objcopy
+SIZE ?= size
+
+# Set host compiler and binutils
+HOSTCC := $(CC)
+HOSTLD := $(LD)
+HOSTAR := $(AR)
+HOSTOBJCOPY := $(OBJCOPY)
+HOSTSIZE := $(SIZE)
+export HOSTCC HOSTLD HOSTAR HOSTOBJCOPY SIZE
+
+# Set target compiler. Defaults to whatever the user has
+# configured as prefix + ye olde gcc commands
+CC := $(call dequote,$(CONFIG_TOOLPREFIX))gcc
+CXX := $(call dequote,$(CONFIG_TOOLPREFIX))c++
+LD := $(call dequote,$(CONFIG_TOOLPREFIX))ld
+AR := $(call dequote,$(CONFIG_TOOLPREFIX))ar
+OBJCOPY := $(call dequote,$(CONFIG_TOOLPREFIX))objcopy
+SIZE := $(call dequote,$(CONFIG_TOOLPREFIX))size
+export CC CXX LD AR OBJCOPY SIZE
+
+PYTHON=$(call dequote,$(CONFIG_PYTHON))
+
+# the app is the main executable built by the project
+APP_ELF:=$(BUILD_DIR_BASE)/$(PROJECT_NAME).elf
+APP_MAP:=$(APP_ELF:.elf=.map)
+APP_BIN:=$(APP_ELF:.elf=.bin)
+
+# Include any Makefile.projbuild file letting components add
+# configuration at the project level
+define includeProjBuildMakefile
+$(if $(V),$(info including $(1)/Makefile.projbuild...))
+COMPONENT_PATH := $(1)
+include $(1)/Makefile.projbuild
+endef
+$(foreach componentpath,$(COMPONENT_PATHS), \
+	$(if $(wildcard $(componentpath)/Makefile.projbuild), \
+		$(eval $(call includeProjBuildMakefile,$(componentpath)))))
+
+# once we know component paths, we can include the config generation targets
+#
+# (bootloader build doesn't need this, config is exported from top-level)
+ifndef IS_BOOTLOADER_BUILD
+include $(IDF_PATH)/make/project_config.mk
+endif
+
+# ELF depends on the library archive files for COMPONENT_LIBRARIES
+# the rules to build these are emitted as part of GenerateComponentTarget below
+#
+# also depends on additional dependencies (linker scripts & binary libraries)
+# stored in COMPONENT_LINKER_DEPS, built via component.mk files' COMPONENT_ADD_LINKER_DEPS variable
+COMPONENT_LINKER_DEPS ?=
+$(APP_ELF): $(foreach libcomp,$(COMPONENT_LIBRARIES),$(BUILD_DIR_BASE)/$(libcomp)/lib$(libcomp).a) $(COMPONENT_LINKER_DEPS) $(COMPONENT_PROJECT_VARS)
+	$(summary) LD $(patsubst $(PWD)/%,%,$@)
+	$(CC) $(LDFLAGS) -o $@ -Wl,-Map=$(APP_MAP)
+
+app: $(APP_BIN)
+ifeq ("$(CONFIG_SECURE_BOOT_ENABLED)$(CONFIG_SECURE_BOOT_BUILD_SIGNED_BINARIES)","y") # secure boot enabled, but remote sign app image
+	@echo "App built but not signed. Signing step via espsecure.py:"
+	@echo "espsecure.py sign_data --keyfile KEYFILE $(APP_BIN)"
+	@echo "Then flash app command is:"
+	@echo $(ESPTOOLPY_WRITE_FLASH) $(CONFIG_APP_OFFSET) $(APP_BIN)
+else
+	@echo "App built. Default flash app command is:"
+	@echo $(ESPTOOLPY_WRITE_FLASH) $(CONFIG_APP_OFFSET) $(APP_BIN)
+endif
+
+all_binaries: $(APP_BIN)
+
+$(BUILD_DIR_BASE):
+	mkdir -p $(BUILD_DIR_BASE)
+
+# Macro for the recursive sub-make for each component
+# $(1) - component directory
+# $(2) - component name only
+#
+# Is recursively expanded by the GenerateComponentTargets macro
+define ComponentMake
++$(MAKE) -C $(BUILD_DIR_BASE)/$(2) -f $(IDF_PATH)/make/component_wrapper.mk COMPONENT_MAKEFILE=$(1)/component.mk COMPONENT_NAME=$(2)
+endef
+
+# Generate top-level component-specific targets for each component
+# $(1) - path to component dir
+# $(2) - name of component
+#
+define GenerateComponentTargets
+.PHONY: component-$(2)-build component-$(2)-clean
+
+component-$(2)-build: check-submodules $(call prereq_if_explicit, component-$(2)-clean) | $(BUILD_DIR_BASE)/$(2)
+	$(call ComponentMake,$(1),$(2)) build
+
+component-$(2)-clean: | $(BUILD_DIR_BASE)/$(2) $(BUILD_DIR_BASE)/$(2)/component_project_vars.mk
+	$(call ComponentMake,$(1),$(2)) clean
+
+$(BUILD_DIR_BASE)/$(2):
+	@mkdir -p $(BUILD_DIR_BASE)/$(2)
+
+# tell make it can build any component's library by invoking the -build target
+# (this target exists for all components even ones which don't build libraries, but it's
+# only invoked for the targets whose libraries appear in COMPONENT_LIBRARIES and hence the
+# APP_ELF dependencies.)
+$(BUILD_DIR_BASE)/$(2)/lib$(2).a: component-$(2)-build
+	$(details) "Target '$$^' responsible for '$$@'" # echo which build target built this file
+
+# add a target to generate the component_project_vars.mk files that
+# are used to inject variables into project make pass (see matching
+# component_project_vars.mk target in component_wrapper.mk).
+#
+# If any component_project_vars.mk file is out of date, the make
+# process will call this target to rebuild it and then restart.
+#
+$(BUILD_DIR_BASE)/$(2)/component_project_vars.mk: $(1)/component.mk $(COMMON_MAKEFILES) $(SDKCONFIG_MAKEFILE) | $(BUILD_DIR_BASE)/$(2)
+	$(call ComponentMake,$(1),$(2)) component_project_vars.mk
+endef
+
+$(foreach component,$(COMPONENT_PATHS),$(eval $(call GenerateComponentTargets,$(component),$(notdir $(component)))))
+$(foreach component,$(TEST_COMPONENT_PATHS),$(eval $(call GenerateComponentTargets,$(component),$(lastword $(subst /, ,$(dir $(component))))_test)))
+
+app-clean: $(addprefix component-,$(addsuffix -clean,$(notdir $(COMPONENT_PATHS))))
+	$(summary) RM $(APP_ELF)
+	rm -f $(APP_ELF) $(APP_BIN) $(APP_MAP)
+
+size: $(APP_ELF)
+	$(PYTHON) $(IDF_PATH)/tools/idf_size.py $(APP_MAP)
+
+size-files: $(APP_ELF)
+	$(PYTHON) $(IDF_PATH)/tools/idf_size.py --files $(APP_MAP)
+
+size-components: $(APP_ELF)
+	$(PYTHON) $(IDF_PATH)/tools/idf_size.py --archives $(APP_MAP)
+
+# NB: this ordering is deliberate (app-clean & bootloader-clean before
+# _config-clean), so config remains valid during all component clean
+# targets
+config-clean: app-clean bootloader-clean
+clean: app-clean bootloader-clean config-clean
+
+# phony target to check if any git submodule listed in COMPONENT_SUBMODULES are missing
+# or out of date, and exit if so. Components can add paths to this variable.
+#
+# This only works for components inside IDF_PATH
+check-submodules:
+
+# Dump the git status for the whole working copy once, then grep it for each submodule. This saves a lot of time on Windows.
+GIT_STATUS := $(shell cd ${IDF_PATH} && git status --porcelain --ignore-submodules=dirty)
+
+# Generate a target to check this submodule
+# $(1) - submodule directory, relative to IDF_PATH
+define GenerateSubmoduleCheckTarget
+check-submodules: $(IDF_PATH)/$(1)/.git
+$(IDF_PATH)/$(1)/.git:
+	@echo "WARNING: Missing submodule $(1)..."
+	[ -e ${IDF_PATH}/.git ] || ( echo "ERROR: esp-idf must be cloned from git to work."; exit 1)
+	[ -x $$(which git) ] || ( echo "ERROR: Need to run 'git submodule init $(1)' in esp-idf root directory."; exit 1)
+	@echo "Attempting 'git submodule update --init $(1)' in esp-idf root directory..."
+	cd ${IDF_PATH} && git submodule update --init $(1)
+
+# Parse 'git status' output to check if the submodule commit is different to expected
+ifneq ("$(filter $(1),$(GIT_STATUS))","")
+$$(info WARNING: esp-idf git submodule $(1) may be out of date. Run 'git submodule update' in IDF_PATH dir to update.)
+endif
+endef
+
+# filter/subst in expression ensures all submodule paths begin with $(IDF_PATH), and then strips that prefix
+# so the argument is suitable for use with 'git submodule' commands
+$(foreach submodule,$(subst $(IDF_PATH)/,,$(filter $(IDF_PATH)/%,$(COMPONENT_SUBMODULES))),$(eval $(call GenerateSubmoduleCheckTarget,$(submodule))))
+
+
+# PHONY target to list components in the build and their paths
+list-components:
+	$(info $(call dequote,$(SEPARATOR)))
+	$(info COMPONENT_DIRS (components searched for here))
+	$(foreach cd,$(COMPONENT_DIRS),$(info $(cd)))
+	$(info $(call dequote,$(SEPARATOR)))
+	$(info COMPONENTS (list of component names))
+	$(info $(COMPONENTS))
+	$(info $(call dequote,$(SEPARATOR)))
+	$(info COMPONENT_PATHS (paths to all components):)
+	$(foreach cp,$(COMPONENT_PATHS),$(info $(cp)))
+
+# print flash command, so users can dump this to config files and download somewhere without idf
+print_flash_cmd:
+	echo $(ESPTOOL_WRITE_FLASH_OPTIONS) $(ESPTOOL_ALL_FLASH_ARGS) | sed -e 's:'$(PWD)/build/'::g'
+
+# Check toolchain version using the output of xtensa-esp32-elf-gcc --version command.
+# The output normally looks as follows
+#     xtensa-esp32-elf-gcc (crosstool-NG crosstool-ng-1.22.0-59-ga194053) 4.8.5
+# The part in brackets is extracted into TOOLCHAIN_COMMIT_DESC variable,
+# the part after the brackets is extracted into TOOLCHAIN_GCC_VER.
+ifdef CONFIG_TOOLPREFIX
+ifndef MAKE_RESTARTS
+TOOLCHAIN_COMMIT_DESC := $(shell $(CC) --version | sed -E -n 's|.*crosstool-ng-([0-9]+).([0-9]+).([0-9]+)-([0-9]+)-g([0-9a-f]{7}).*|\1.\2.\3-\4-g\5|gp')
+TOOLCHAIN_GCC_VER := $(shell $(CC) --version | sed -E -n 's|xtensa-esp32-elf-gcc.*\ \(.*\)\ (.*)|\1|gp')
+
+# Officially supported version(s)
+SUPPORTED_TOOLCHAIN_COMMIT_DESC := 1.22.0-80-g6c4433a
+SUPPORTED_TOOLCHAIN_GCC_VERSIONS := 5.2.0
+
+ifdef TOOLCHAIN_COMMIT_DESC
+ifneq ($(TOOLCHAIN_COMMIT_DESC), $(SUPPORTED_TOOLCHAIN_COMMIT_DESC))
+$(info WARNING: Toolchain version is not supported: $(TOOLCHAIN_COMMIT_DESC))
+$(info Expected to see version: $(SUPPORTED_TOOLCHAIN_COMMIT_DESC))
+$(info Please check ESP-IDF setup instructions and update the toolchain, or proceed at your own risk.)
+endif
+ifeq (,$(findstring $(TOOLCHAIN_GCC_VER), $(SUPPORTED_TOOLCHAIN_GCC_VERSIONS)))
+$(info WARNING: Compiler version is not supported: $(TOOLCHAIN_GCC_VER))
+$(info Expected to see version(s): $(SUPPORTED_TOOLCHAIN_GCC_VERSIONS))
+$(info Please check ESP-IDF setup instructions and update the toolchain, or proceed at your own risk.)
+endif
+else
+$(info WARNING: Failed to find Xtensa toolchain, may need to alter PATH or set one in the configuration menu)
+endif # TOOLCHAIN_COMMIT_DESC
+
+endif #MAKE_RESTARTS
+endif #CONFIG_TOOLPREFIX
diff --git a/make/project_config.mk b/make/project_config.mk
new file mode 100644
index 0000000..0a212cd
--- /dev/null
+++ b/make/project_config.mk
@@ -0,0 +1,97 @@
+# Makefile support for the menuconfig system
+
+#Find all Kconfig files for all components
+COMPONENT_KCONFIGS := $(foreach component,$(COMPONENT_PATHS),$(wildcard $(component)/Kconfig))
+COMPONENT_KCONFIGS_PROJBUILD := $(foreach component,$(COMPONENT_PATHS),$(wildcard $(component)/Kconfig.projbuild))
+
+#For doing make menuconfig etc
+KCONFIG_TOOL_DIR=$(IDF_PATH)/tools/kconfig
+
+# set SDKCONFIG to the project's sdkconfig,
+# unless it's overriden (happens for bootloader)
+SDKCONFIG ?= $(PROJECT_PATH)/sdkconfig
+
+# SDKCONFIG_DEFAULTS is an optional file containing default
+# overrides (usually used for esp-idf examples)
+SDKCONFIG_DEFAULTS ?= $(PROJECT_PATH)/sdkconfig.defaults
+
+# reset MAKEFLAGS as the menuconfig makefile uses implicit compile rules
+$(KCONFIG_TOOL_DIR)/mconf $(KCONFIG_TOOL_DIR)/conf: $(wildcard $(KCONFIG_TOOL_DIR)/*.c)
+	MAKEFLAGS="" CC=$(HOSTCC) LD=$(HOSTLD) \
+	$(MAKE) -C $(KCONFIG_TOOL_DIR)
+
+ifeq ("$(wildcard $(SDKCONFIG))","")
+ifeq ("$(filter defconfig clean% %clean, $(MAKECMDGOALS))","")
+# if no configuration file is present and defconfig or clean
+# is not a named target, run defconfig then menuconfig to get the initial config
+$(SDKCONFIG): menuconfig
+menuconfig: defconfig
+else
+# otherwise, just run defconfig
+$(SDKCONFIG): defconfig
+endif
+endif
+
+# macro for the commands to run kconfig tools conf or mconf.
+# $1 is the name (& args) of the conf tool to run
+define RunConf
+	mkdir -p $(BUILD_DIR_BASE)/include/config
+	cd $(BUILD_DIR_BASE); KCONFIG_AUTOHEADER=$(abspath $(BUILD_DIR_BASE)/include/sdkconfig.h) \
+	COMPONENT_KCONFIGS="$(COMPONENT_KCONFIGS)" KCONFIG_CONFIG=$(SDKCONFIG) \
+	COMPONENT_KCONFIGS_PROJBUILD="$(COMPONENT_KCONFIGS_PROJBUILD)" \
+	$(KCONFIG_TOOL_DIR)/$1 $(IDF_PATH)/Kconfig
+endef
+
+ifndef MAKE_RESTARTS
+# menuconfig, defconfig and "GENCONFIG" configuration generation only
+# ever run on the first make pass, subsequent passes don't run these
+# (make often wants to re-run them as the conf tool can regenerate the
+# sdkconfig input file as an output file, but this is not what the
+# user wants - a single config pass is enough to produce all output
+# files.)
+#
+# To prevent problems missing genconfig, ensure none of these targets
+# depend on any prerequisite that may cause a make restart as part of
+# the prerequisite's own recipe.
+
+menuconfig: $(KCONFIG_TOOL_DIR)/mconf
+	$(summary) MENUCONFIG
+ifdef BATCH_BUILD
+	@echo "Can't run interactive configuration inside non-interactive build process."
+	@echo ""
+	@echo "Open a command line terminal and run 'make menuconfig' from there."
+	@echo "See esp-idf documentation for more details."
+	@exit 1
+else
+	$(call RunConf,mconf)
+endif
+
+# defconfig creates a default config, based on SDKCONFIG_DEFAULTS if present
+defconfig: $(KCONFIG_TOOL_DIR)/conf
+	$(summary) DEFCONFIG
+ifneq ("$(wildcard $(SDKCONFIG_DEFAULTS))","")
+	cat $(SDKCONFIG_DEFAULTS) >> $(SDKCONFIG)  # append defaults to sdkconfig, will override existing values
+endif
+	$(call RunConf,conf --olddefconfig)
+
+# if neither defconfig or menuconfig are requested, use the GENCONFIG rule to
+# ensure generated config files are up to date
+$(SDKCONFIG_MAKEFILE) $(BUILD_DIR_BASE)/include/sdkconfig.h: $(KCONFIG_TOOL_DIR)/conf $(SDKCONFIG) $(COMPONENT_KCONFIGS) $(COMPONENT_KCONFIGS_PROJBUILD) | $(call prereq_if_explicit,defconfig) $(call prereq_if_explicit,menuconfig)
+	$(summary) GENCONFIG
+ifdef BATCH_BUILD  # can't prompt for new config values like on terminal
+	$(call RunConf,conf --olddefconfig)
+endif
+	$(call RunConf,conf --silentoldconfig)
+	touch $(SDKCONFIG_MAKEFILE) $(BUILD_DIR_BASE)/include/sdkconfig.h  # ensure newer than sdkconfig
+
+else  # "$(MAKE_RESTARTS)" != ""
+# on subsequent make passes, skip config generation entirely
+defconfig:
+menuconfig:
+endif
+
+.PHONY: config-clean defconfig menuconfig
+config-clean:
+	$(summary) RM CONFIG
+	MAKEFLAGS="" $(MAKE) -C $(KCONFIG_TOOL_DIR) clean
+	rm -rf $(BUILD_DIR_BASE)/include/config $(BUILD_DIR_BASE)/include/sdkconfig.h
-- 
2.11.4.GIT