OTA - redirection support + bootloader

components/bootloader/subproject/Makefile

@@ -0,0 +1,35 @@
+#
+# This is a project Makefile. It is assumed the directory this Makefile resides in is a
+# project subdirectory.
+#
+ifeq ("$(MAKELEVEL)","0")
+$(error Bootloader makefile expects to be run as part of 'make bootloader' from a top-level project.)
+endif
+
+PROJECT_NAME := bootloader
+
+COMPONENTS := esptool_py bootloader_support log spi_flash micro-ecc soc main efuse
+
+# Clear C and CXX from top level project
+CFLAGS =
+CXXFLAGS =
+
+#We cannot include the idf_target, esp_rom, esp_common component directly but we need their includes.
+CFLAGS += -I $(IDF_PATH)/components/$(IDF_TARGET)/include
+CFLAGS += -I $(IDF_PATH)/components/esp_rom/include
+CFLAGS += -I $(IDF_PATH)/components/esp_common/include
+CFLAGS += -I $(IDF_PATH)/components/xtensa/include -I $(IDF_PATH)/components/xtensa/$(IDF_TARGET)/include
+
+# The bootloader pseudo-component is also included in this build, for its Kconfig.projbuild to be included.
+#
+# IS_BOOTLOADER_BUILD tells the component Makefile.projbuild to be a no-op
+IS_BOOTLOADER_BUILD := 1
+export IS_BOOTLOADER_BUILD
+
+# BOOTLOADER_BUILD macro is the same, for source file changes
+CFLAGS += -D BOOTLOADER_BUILD=1
+
+# include the top-level "project" include directory, for sdkconfig.h
+CFLAGS += -I$(BUILD_DIR_BASE)/../include
+
+include $(IDF_PATH)/make/project.mk