Makefile - nest-learning-thermostat/5.1.5/u-boot - Git at Google

 #
 #    Copyright (c) 2010-2011 Nest, Inc.
 #    All rights reserved.
 #
 #    This document is the property of Nest Labs. It is considered
 #    confidential and proprietary information.
 #
 #    This document may not be reproduced or transmitted in any form,
 #    in whole or in part, without the express written permission of
 #    Nest Labs.
 #
 #    Description:
 #      This file is the makefile for the Universal Bootloader, u-boot.
 #

 .NOTPARALLEL:

 include pre.mak

 PackageRoot		:= .

 PackageSeparator	:=

 PackageVersion		:=
 PackageSourceDir	:= $(PackageRoot)/$(UBootPackageName)$(PackageSeparator)$(PackageVersion)

 PackageBuildMakefile	= $(call GenerateBuildPaths,include/config.mk)

 CleanPaths		+= $(PackageLicenseFile)

 CP			= cp
 DD			= dd
 LN			= ln
 TAR			= tar
 MKDIR			= mkdir
 CHMOD			= chmod
 PRINTF			= printf
 PUSHD			= pushd
 POPD			= popd
 FSL_HAB_SIGN		= $(BuildRoot)/build/scripts/fsl_hab_sign.sh
 FSL_CST			= $(BuildRoot)/build/tools/host/i686-pc-linux-gnu/bin/freescale-cst

 GeneratedBuildExtra	:= $(shell bash $(BuildExtraScriptSourcePath) --build-version $(BuildVersion))

 LocalBuildExtra		= $(if $(call IsVariable,BuildExtra,undefined),$(call UseIfNotEmpty,$(GeneratedBuildExtra)),$(call UseIfNotEmpty,$(BuildExtra)))

 #
 # Build and result paths for staging targets
 #

 UBootResultBinDir	:= $(call GenerateResultPaths,,bin)
 UBootResultSbinDir	:= $(call GenerateResultPaths,,sbin)

 UBootPrintEnvBuildPath	:= $(call GenerateBuildPaths,tools/env/fw_printenv)
 UBootPrintEnvResultPath	:= $(call GenerateResultPaths,,sbin/fw_printenv)

 UBootSetEnvResultPath	:= $(call GenerateResultPaths,,sbin/fw_setenv)

 UBootMkimageBuildPath	:= $(call GenerateBuildPaths,tools/mkimage)
 UBootMkimageResultPath	:= $(call GenerateResultPaths,,bin/mkimage)

 UnsignedUBootBuildPath	:= $(call GenerateBuildPaths,$(UBootImageFile))

 #
 # If UBootSignedImageFile AND UBootSignedSDPImageFile are defined, we need to do
 # an extra step and sign UBootImageFile to produce signed binaries.
 #
 # There are three different ways we can generate this signed binary:
 # 1) Copy a signed image from within the Git repo*    [ Default behavior if the appropriate signed image folder is present ]
 # 2) Copy an unsigned image from the build folder*    [ Fallback behavior if the appropriate signed image folder is not present (deleted or not yet present) ]
 # 3) Sign it locally using the private keys           [ Force this by passing 'SIGN_BOOTLOADER=true' on make cmdline ]
 #
 # *Also generates a signing .tgz archive in the u-boot results folder that can be unpacked on an offline
 #  signing workstation that has the necessary signing keys and used to sign the image. It contains:
 #  1) The code signing binary: freescale-cst
 #  2) The code signing helper script: fsl_hab_sign.sh
 #  3) The unsigned u-boot image
 #  4) A top-level signing script that defines the input and output filenames, for documentation purposes, and so that we are consistent.
 #
 ifneq "$(and $(UBootSignedImageFile),$(UBootSignedSDPImageFile))" ""
 SignedUBootResultPath	= $(call GenerateResultPaths,,$(UBootSignedImageFile))
 SignedSDPUBootResultPath= $(call GenerateResultPaths,,$(UBootSignedSDPImageFile))
 BuildResults		= $(SignedUBootResultPath) $(SignedSDPUBootResultPath)

 # Generate a signing .tgz archive
 UBootSigningArchiveResultPath	= $(call GenerateResultPaths,,u-boot-unsigned-$(BuildVersion)-$(BuildProduct)-$(BuildConfig)$(LocalBuildExtra).tgz)
 define SIGNING_SCRIPT
 #!/bin/bash
 set -e
 ./$(notdir $(FSL_HAB_SIGN)) $(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) $(basename $(UBootSignedImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootSignedImageFile))
 ./$(notdir $(FSL_HAB_SIGN)) --sdp $(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) $(basename $(UBootSignedImageFile))-sdp-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootSignedImageFile))
 echo "Done, no errors"

 endef
 export SIGNING_SCRIPT
 GenerateUBootSigningArchive	= $(eval TMPDIR := $(shell mktemp -d)) \
 				  $(MKDIR) -p $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
 				  $(CP) $(FSL_HAB_SIGN) $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
 				  $(CP) $(FSL_CST) $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
 				  $(CP) $(1) $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/$(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) && \
 				  $(PRINTF) "$$SIGNING_SCRIPT" > $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/sign.sh && \
 				  $(CHMOD) u+x $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/sign.sh && \
 				  $(PUSHD) $(TMPDIR) && sha256sum $(BuildProduct)/$(BuildConfig)/* > $(BuildProduct)/$(BuildConfig)/SHA256SUMS && $(POPD) && \
 				  $(TAR) -czf $(UBootSigningArchiveResultPath) --directory $(TMPDIR) $(BuildProduct) && \
 				  $(RM) -rf $(TMPDIR)

 ifdef SIGN_BOOTLOADER
 # This is option (3) above
 # This option also copies the signed result, places it into the signed u-boot images folder with a name that reflects the
 # BuildExtra (tag, last commit hash, etc) and updates the symlinks to it so that it is ready to commit into the repo.
 GenerateSignedResult	= $(Echo) "Signing result \"$(call GenerateBuildRootEllipsedPath,$2)\" locally" && \
 			  $(FSL_HAB_SIGN) $(3) $(1) $(2) $(LocalBuildExtra) && \
 			  $(CP) $(2) $(UBootSignedImagesFolder)/$(basename $(notdir $(2)))$(LocalBuildExtra)$(suffix $(2)) && \
 			  $(LN) -fs $(basename $(notdir $(2)))$(LocalBuildExtra)$(suffix $(2)) $(UBootSignedImagesFolder)/$(notdir $(2))
 else ifneq ($(wildcard $(UBootSignedImagesFolder)),)
 # This is option (1) above
 GenerateSignedResult	= $(Echo) "Copying signed result \"$(call GenerateBuildRootEllipsedPath,$2)\" from repo ($(UBootSignedImagesFolder)/$(notdir $(2)))" && \
 			  $(call GenerateUBootSigningArchive,$(1)) && \
 			  $(CP) $(UBootSignedImagesFolder)/$(notdir $(2)) $(2)
 else
 # This is option (2) above
 #
 # Note that setting CONFIG_SECURE_BOOT in the U-boot config causes a 'CSF 0x2000' command to be
 # added to the mkimage config, which causes the CSF field in the the IVT header to be nonzero,
 # and increases the length of the image given in the header by 0x2000 Bytes. If cases such as this,
 # where we don't actually do the signing and append the CSF data, we need to zero the field and
 # append 0x2000 Bytes of zeros, so that the boot ROM won't die trying to read it.
 GenerateSignedResult	= $(Echo) "Copying result \"$(call GenerateBuildRootEllipsedPath,$2)\" without signing" && \
 			  $(call GenerateUBootSigningArchive,$(1)) && \
 			  $(CP) $(1) $(2) && \
 			  $(DD) if=/dev/zero of=$(2) seek=24 bs=1 count=4 conv=notrunc > /dev/null 2>&1 && \
 			  $(DD) if=/dev/zero of=$(2) bs=$$((0x2000)) count=1 conv=notrunc oflag=append > /dev/null 2>&1
 endif

 else
 UnsignedUBootResultPath	= $(call GenerateResultPaths,,$(UBootImageFile))
 BuildResults		= $(UnsignedUBootResultPath)
 endif

 NestBuildDefines	:= NEST_BUILD_CONFIG_$(call ToUpper,$(BuildConfig)) NEST_BUILD_CONFIG=\\\"$(BuildConfig)\\\"
 NestBuildDefineFlags	:= $(call ToolGenerateDefineArgument,$(NestBuildDefines))


 # The diamond1 and j49 u-boot builds require the HOSTCC and HOSTSTRIP flags to point to the cross-toolchain so that
 # fw_printenv/fw_setenv will be built for the target arch. Doing this with the newer (2014.04) diamond3 and flintstone
 # builds causes the host tools to be cross-compiled, and is unnecessary, which is more in line with what seems logical.
 ifeq ($(UBootPackageName),u-boot)
 toolHostCCFlags		= HOSTCC="$(CC)" HOSTSTRIP=$(STRIP)
 else
 toolHostCCFlags		=
 endif

 all: $(PackageDefaultGoal)

 # Generate the package license contents.

 $(PackageSourceDir)/COPYING: source

 $(PackageLicenseFile): $(PackageSourceDir)/COPYING
 	$(copy-result)

 # We are building this package from version-controller source, so
 # there is nothing to do for this target goal.

 $(PackageSourceDir):

 # Prepare the sources.

 .PHONY: source
 source: | $(PackageSourceDir)

 # Patch the sources, if necessary.

 .PHONY: patch
 patch: source

 # U-Boot has no way of explicitly setting CC, LD, OBJCOPY, et al and
 # instead relies on the value of CROSS_COMPILE. Consequently, we have
 # to ensure that 'ToolBinDir' is in 'PATH' so that the kernel build
 # infrastructure can find $(CROSS_COMPILE)gcc, $(CROSS_COMPILE)ld, et
 # al.

 configure build stage: PATH := $(PATH):$(ToolBinDir)
 configure build stage: CROSS_COMPILE := $(CCACHE) $(CROSS_COMPILE)

 # Generate the package build makefile.

 $(PackageBuildMakefile): | $(PackageSourceDir) $(BuildDirectory)
 	$(Verbose)unset MAKEFLAGS && \
 	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
 	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
 	O=$(CURDIR)/$(BuildDirectory) \
 	$(UBootDefaultConfig)

 # Configure the source for building.

 .PHONY: configure
 configure: source $(PackageBuildMakefile)

 # Build the source.

 .PHONY: build
 build: $(UnsignedUBootBuildPath)

 $(UnsignedUBootBuildPath): configure
 	$(Verbose)unset MAKEFLAGS && \
 	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
 	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
 	O=$(CURDIR)/$(BuildDirectory) \
 	NestBuildDefineFlags="$(NestBuildDefineFlags)" \
 	all

 $(UBootPrintEnvBuildPath): configure $(UnsignedUBootBuildPath)
 	$(Verbose)unset MAKEFLAGS && \
 	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
 	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
 	O=$(CURDIR)/$(BuildDirectory) \
 	$(toolHostCCFlags) \
 	TOOLSUBDIRS=env \
 	NestBuildDefineFlags="$(NestBuildDefineFlags)" \
 	env tools

 $(UnsignedUBootBuildPath): build

 # Stage the build to a temporary installation area.
 #
 # U-Boot does not support a notion of installing, so we have to
 # cherry-pick the components we want from the build directory and
 # copy/install them to the results directory.

 .PHONY: stage stage-target stage-target-tools stage-host-tools
 stage: stage-target stage-target-tools stage-host-tools

 stage-target: $(BuildResults)
 	$(Verbose)$(CP) -f $(call GenerateBuildPaths,System.map) $(ResultDirectory)

 #
 # Targets and commands for signing compiled images.
 # Generates a regular signed image for NAND boot AND a special SDP one for USB DFU boot
 #

 $(UnsignedUBootResultPath): $(UnsignedUBootBuildPath) | $(ResultDirectory)
 	$(Verbose)$(CP) -f $< $@

 $(SignedUBootResultPath): $(UnsignedUBootBuildPath) | $(ResultDirectory)
 	$(Verbose)$(call GenerateSignedResult,$<,$@,)

 $(SignedSDPUBootResultPath): $(UnsignedUBootBuildPath) | $(ResultDirectory)
 	$(Verbose)$(call GenerateSignedResult,$<,$@,--sdp)

 #
 # Targets and commands for staging target (i.e cross-compiled) tools.
 #

 $(UBootResultSbinDir):
 	$(create-directory)

 $(UBootPrintEnvResultPath): $(UBootPrintEnvBuildPath) | $(UBootResultSbinDir)
 	$(copy-result)

 $(UBootSetEnvResultPath): $(UBootPrintEnvBuildPath) | $(UBootResultSbinDir)
 	$(Echo) "Creating \"$(call GenerateBuildRootEllipsedPath,$@)\""
 	$(Verbose)ln -sf fw_printenv "$(@)"

 stage-target-tools: $(UBootPrintEnvResultPath) $(UBootSetEnvResultPath)

 #
 # Targets and commands for staging host (i.e. natively-compiled) tools
 # that may be used elsewhere in the build.
 #

 $(UBootResultBinDir):
 	$(create-directory)

 $(UBootMkimageBuildPath): build

 $(UBootMkimageResultPath): $(UBootMkimageBuildPath) | $(UBootResultBinDir)
 	$(copy-result)

 stage-host-tools: $(UBootMkimageResultPath)

 clean:
 	$(Verbose)$(RM) $(RMFLAGS) -r $(BuildDirectory)
 	$(Verbose)$(RM) $(RMFLAGS) -r $(ResultDirectory)

 include post.mak
	#
	# Copyright (c) 2010-2011 Nest, Inc.
	# All rights reserved.
	#
	# This document is the property of Nest Labs. It is considered
	# confidential and proprietary information.
	#
	# This document may not be reproduced or transmitted in any form,
	# in whole or in part, without the express written permission of
	# Nest Labs.
	#
	# Description:
	# This file is the makefile for the Universal Bootloader, u-boot.
	#

	.NOTPARALLEL:

	include pre.mak

	PackageRoot := .

	PackageSeparator :=

	PackageVersion :=
	PackageSourceDir := $(PackageRoot)/$(UBootPackageName)$(PackageSeparator)$(PackageVersion)

	PackageBuildMakefile = $(call GenerateBuildPaths,include/config.mk)

	CleanPaths += $(PackageLicenseFile)

	CP = cp
	DD = dd
	LN = ln
	TAR = tar
	MKDIR = mkdir
	CHMOD = chmod
	PRINTF = printf
	PUSHD = pushd
	POPD = popd
	FSL_HAB_SIGN = $(BuildRoot)/build/scripts/fsl_hab_sign.sh
	FSL_CST = $(BuildRoot)/build/tools/host/i686-pc-linux-gnu/bin/freescale-cst

	GeneratedBuildExtra := $(shell bash $(BuildExtraScriptSourcePath) --build-version $(BuildVersion))

	LocalBuildExtra = $(if $(call IsVariable,BuildExtra,undefined),$(call UseIfNotEmpty,$(GeneratedBuildExtra)),$(call UseIfNotEmpty,$(BuildExtra)))

	#
	# Build and result paths for staging targets
	#

	UBootResultBinDir := $(call GenerateResultPaths,,bin)
	UBootResultSbinDir := $(call GenerateResultPaths,,sbin)

	UBootPrintEnvBuildPath := $(call GenerateBuildPaths,tools/env/fw_printenv)
	UBootPrintEnvResultPath := $(call GenerateResultPaths,,sbin/fw_printenv)

	UBootSetEnvResultPath := $(call GenerateResultPaths,,sbin/fw_setenv)

	UBootMkimageBuildPath := $(call GenerateBuildPaths,tools/mkimage)
	UBootMkimageResultPath := $(call GenerateResultPaths,,bin/mkimage)

	UnsignedUBootBuildPath := $(call GenerateBuildPaths,$(UBootImageFile))

	#
	# If UBootSignedImageFile AND UBootSignedSDPImageFile are defined, we need to do
	# an extra step and sign UBootImageFile to produce signed binaries.
	#
	# There are three different ways we can generate this signed binary:
	# 1) Copy a signed image from within the Git repo* [ Default behavior if the appropriate signed image folder is present ]
	# 2) Copy an unsigned image from the build folder* [ Fallback behavior if the appropriate signed image folder is not present (deleted or not yet present) ]
	# 3) Sign it locally using the private keys [ Force this by passing 'SIGN_BOOTLOADER=true' on make cmdline ]
	#
	# *Also generates a signing .tgz archive in the u-boot results folder that can be unpacked on an offline
	# signing workstation that has the necessary signing keys and used to sign the image. It contains:
	# 1) The code signing binary: freescale-cst
	# 2) The code signing helper script: fsl_hab_sign.sh
	# 3) The unsigned u-boot image
	# 4) A top-level signing script that defines the input and output filenames, for documentation purposes, and so that we are consistent.
	#
	ifneq "$(and $(UBootSignedImageFile),$(UBootSignedSDPImageFile))" ""
	SignedUBootResultPath = $(call GenerateResultPaths,,$(UBootSignedImageFile))
	SignedSDPUBootResultPath= $(call GenerateResultPaths,,$(UBootSignedSDPImageFile))
	BuildResults = $(SignedUBootResultPath) $(SignedSDPUBootResultPath)

	# Generate a signing .tgz archive
	UBootSigningArchiveResultPath = $(call GenerateResultPaths,,u-boot-unsigned-$(BuildVersion)-$(BuildProduct)-$(BuildConfig)$(LocalBuildExtra).tgz)
	define SIGNING_SCRIPT
	#!/bin/bash
	set -e
	./$(notdir $(FSL_HAB_SIGN)) $(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) $(basename $(UBootSignedImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootSignedImageFile))
	./$(notdir $(FSL_HAB_SIGN)) --sdp $(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) $(basename $(UBootSignedImageFile))-sdp-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootSignedImageFile))
	echo "Done, no errors"

	endef
	export SIGNING_SCRIPT
	GenerateUBootSigningArchive = $(eval TMPDIR := $(shell mktemp -d)) \
	$(MKDIR) -p $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
	$(CP) $(FSL_HAB_SIGN) $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
	$(CP) $(FSL_CST) $(TMPDIR)/$(BuildProduct)/$(BuildConfig) && \
	$(CP) $(1) $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/$(basename $(UBootImageFile))-$(BuildVersion)$(LocalBuildExtra)$(suffix $(UBootImageFile)) && \
	$(PRINTF) "$$SIGNING_SCRIPT" > $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/sign.sh && \
	$(CHMOD) u+x $(TMPDIR)/$(BuildProduct)/$(BuildConfig)/sign.sh && \
	$(PUSHD) $(TMPDIR) && sha256sum $(BuildProduct)/$(BuildConfig)/* > $(BuildProduct)/$(BuildConfig)/SHA256SUMS && $(POPD) && \
	$(TAR) -czf $(UBootSigningArchiveResultPath) --directory $(TMPDIR) $(BuildProduct) && \
	$(RM) -rf $(TMPDIR)

	ifdef SIGN_BOOTLOADER
	# This is option (3) above
	# This option also copies the signed result, places it into the signed u-boot images folder with a name that reflects the
	# BuildExtra (tag, last commit hash, etc) and updates the symlinks to it so that it is ready to commit into the repo.
	GenerateSignedResult = $(Echo) "Signing result \"$(call GenerateBuildRootEllipsedPath,$2)\" locally" && \
	$(FSL_HAB_SIGN) $(3) $(1) $(2) $(LocalBuildExtra) && \
	$(CP) $(2) $(UBootSignedImagesFolder)/$(basename $(notdir $(2)))$(LocalBuildExtra)$(suffix $(2)) && \
	$(LN) -fs $(basename $(notdir $(2)))$(LocalBuildExtra)$(suffix $(2)) $(UBootSignedImagesFolder)/$(notdir $(2))
	else ifneq ($(wildcard $(UBootSignedImagesFolder)),)
	# This is option (1) above
	GenerateSignedResult = $(Echo) "Copying signed result \"$(call GenerateBuildRootEllipsedPath,$2)\" from repo ($(UBootSignedImagesFolder)/$(notdir $(2)))" && \
	$(call GenerateUBootSigningArchive,$(1)) && \
	$(CP) $(UBootSignedImagesFolder)/$(notdir $(2)) $(2)
	else
	# This is option (2) above
	#
	# Note that setting CONFIG_SECURE_BOOT in the U-boot config causes a 'CSF 0x2000' command to be
	# added to the mkimage config, which causes the CSF field in the the IVT header to be nonzero,
	# and increases the length of the image given in the header by 0x2000 Bytes. If cases such as this,
	# where we don't actually do the signing and append the CSF data, we need to zero the field and
	# append 0x2000 Bytes of zeros, so that the boot ROM won't die trying to read it.
	GenerateSignedResult = $(Echo) "Copying result \"$(call GenerateBuildRootEllipsedPath,$2)\" without signing" && \
	$(call GenerateUBootSigningArchive,$(1)) && \
	$(CP) $(1) $(2) && \
	$(DD) if=/dev/zero of=$(2) seek=24 bs=1 count=4 conv=notrunc > /dev/null 2>&1 && \
	$(DD) if=/dev/zero of=$(2) bs=$$((0x2000)) count=1 conv=notrunc oflag=append > /dev/null 2>&1
	endif

	else
	UnsignedUBootResultPath = $(call GenerateResultPaths,,$(UBootImageFile))
	BuildResults = $(UnsignedUBootResultPath)
	endif

	NestBuildDefines := NEST_BUILD_CONFIG_$(call ToUpper,$(BuildConfig)) NEST_BUILD_CONFIG=\\\"$(BuildConfig)\\\"
	NestBuildDefineFlags := $(call ToolGenerateDefineArgument,$(NestBuildDefines))


	# The diamond1 and j49 u-boot builds require the HOSTCC and HOSTSTRIP flags to point to the cross-toolchain so that
	# fw_printenv/fw_setenv will be built for the target arch. Doing this with the newer (2014.04) diamond3 and flintstone
	# builds causes the host tools to be cross-compiled, and is unnecessary, which is more in line with what seems logical.
	ifeq ($(UBootPackageName),u-boot)
	toolHostCCFlags = HOSTCC="$(CC)" HOSTSTRIP=$(STRIP)
	else
	toolHostCCFlags =
	endif

	all: $(PackageDefaultGoal)

	# Generate the package license contents.

	$(PackageSourceDir)/COPYING: source

	$(PackageLicenseFile): $(PackageSourceDir)/COPYING
	$(copy-result)

	# We are building this package from version-controller source, so
	# there is nothing to do for this target goal.

	$(PackageSourceDir):

	# Prepare the sources.

	.PHONY: source
	source: \| $(PackageSourceDir)

	# Patch the sources, if necessary.

	.PHONY: patch
	patch: source

	# U-Boot has no way of explicitly setting CC, LD, OBJCOPY, et al and
	# instead relies on the value of CROSS_COMPILE. Consequently, we have
	# to ensure that 'ToolBinDir' is in 'PATH' so that the kernel build
	# infrastructure can find $(CROSS_COMPILE)gcc, $(CROSS_COMPILE)ld, et
	# al.

	configure build stage: PATH := $(PATH):$(ToolBinDir)
	configure build stage: CROSS_COMPILE := $(CCACHE) $(CROSS_COMPILE)

	# Generate the package build makefile.

	$(PackageBuildMakefile): \| $(PackageSourceDir) $(BuildDirectory)
	$(Verbose)unset MAKEFLAGS && \
	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
	O=$(CURDIR)/$(BuildDirectory) \
	$(UBootDefaultConfig)

	# Configure the source for building.

	.PHONY: configure
	configure: source $(PackageBuildMakefile)

	# Build the source.

	.PHONY: build
	build: $(UnsignedUBootBuildPath)

	$(UnsignedUBootBuildPath): configure
	$(Verbose)unset MAKEFLAGS && \
	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
	O=$(CURDIR)/$(BuildDirectory) \
	NestBuildDefineFlags="$(NestBuildDefineFlags)" \
	all

	$(UBootPrintEnvBuildPath): configure $(UnsignedUBootBuildPath)
	$(Verbose)unset MAKEFLAGS && \
	$(MAKE) $(JOBSFLAG) -C $(PackageSourceDir) \
	INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
	O=$(CURDIR)/$(BuildDirectory) \
	$(toolHostCCFlags) \
	TOOLSUBDIRS=env \
	NestBuildDefineFlags="$(NestBuildDefineFlags)" \
	env tools

	$(UnsignedUBootBuildPath): build

	# Stage the build to a temporary installation area.
	#
	# U-Boot does not support a notion of installing, so we have to
	# cherry-pick the components we want from the build directory and
	# copy/install them to the results directory.

	.PHONY: stage stage-target stage-target-tools stage-host-tools
	stage: stage-target stage-target-tools stage-host-tools

	stage-target: $(BuildResults)
	$(Verbose)$(CP) -f $(call GenerateBuildPaths,System.map) $(ResultDirectory)

	#
	# Targets and commands for signing compiled images.
	# Generates a regular signed image for NAND boot AND a special SDP one for USB DFU boot
	#

	$(UnsignedUBootResultPath): $(UnsignedUBootBuildPath) \| $(ResultDirectory)
	$(Verbose)$(CP) -f $< $@

	$(SignedUBootResultPath): $(UnsignedUBootBuildPath) \| $(ResultDirectory)
	$(Verbose)$(call GenerateSignedResult,$<,$@,)

	$(SignedSDPUBootResultPath): $(UnsignedUBootBuildPath) \| $(ResultDirectory)
	$(Verbose)$(call GenerateSignedResult,$<,$@,--sdp)

	#
	# Targets and commands for staging target (i.e cross-compiled) tools.
	#

	$(UBootResultSbinDir):
	$(create-directory)

	$(UBootPrintEnvResultPath): $(UBootPrintEnvBuildPath) \| $(UBootResultSbinDir)
	$(copy-result)

	$(UBootSetEnvResultPath): $(UBootPrintEnvBuildPath) \| $(UBootResultSbinDir)
	$(Echo) "Creating \"$(call GenerateBuildRootEllipsedPath,$@)\""
	$(Verbose)ln -sf fw_printenv "$(@)"

	stage-target-tools: $(UBootPrintEnvResultPath) $(UBootSetEnvResultPath)

	#
	# Targets and commands for staging host (i.e. natively-compiled) tools
	# that may be used elsewhere in the build.
	#

	$(UBootResultBinDir):
	$(create-directory)

	$(UBootMkimageBuildPath): build

	$(UBootMkimageResultPath): $(UBootMkimageBuildPath) \| $(UBootResultBinDir)
	$(copy-result)

	stage-host-tools: $(UBootMkimageResultPath)

	clean:
	$(Verbose)$(RM) $(RMFLAGS) -r $(BuildDirectory)
	$(Verbose)$(RM) $(RMFLAGS) -r $(ResultDirectory)

	include post.mak