############################################################################
# Makefile
#
# SPDX-License-Identifier: Apache-2.0
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.  The
# ASF licenses this file to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance with the
# License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
# License for the specific language governing permissions and limitations
# under the License.
#
############################################################################


############################################################################
# NXBASE - Mandatory variable.  Gets exported to all sub-makes.
#
# The NXBASE variable should always point to the top-level NuttX directory.
# Ideally,  it should be exported as an envvar rather than being set as
# argument to make.
#
# Example:
#   ~/.bashrc: export NXBASE=/path/to/nuttx
#   ~/.zshrc:  export NXBASE=/path/to/nuttx
############################################################################

ifeq ($(realpath ${NXBASE}),)
  $(error Build stopped, NXBASE required)
else
  export NXBASE
endif

############################################################################
# NXOUT - Mandatory variable.  Gets exported to all sub-makes.
# 
# The NXOUT variable defines the output directory for the build.
# It is infered to the default ${NXBASE}/build directory.  This path
# is reserved by the NuttX build system.
############################################################################

NXOUT ?= $(realpath ${NXBASE}/build)
export NXOUT

############################################################################
# ARCH - Mandatory variable.  Gets exported.  Mainly used in Kconfig.
#
# Rather than depending on the Kconfig system to set the architecture,
# which still needs initial manual setup,  the architecture can be set 
# ahead of time.  This still require setting the arch manually,  but avoids
# relying on Kconfig to do so.  This greatly simplifies Kconfig "tree". 
# 
# The architecture must be resolved early on in the build system.  the 
# supported architectures are stored in the ARCHS variable.
############################################################################

ARCHS := arm risc-v sim

ifeq (${ARCH},)
  $(error Build stopped, ARCH not set)
endif

ifeq ($(findstring ${ARCH}, ${ARCHS}),)
  $(info Currently supported ARCHS: ${ARCHS})
  $(error Build stopped, ARCH not supported)
endif

export ARCH

TOOLCHAIN ?= gcc
TOOLCHAIN := ${NXBASE}/tools/${ARCH}/toolchain/${TOOLCHAIN}.defs
ifeq ($(realpath ${TOOLCHAIN}),)
  $(error Build stopped, TOOLCHAIN not found)
else
  export TOOLCHAIN
endif

# Force the BCFG to always be passed to build process.
# This new Environment variable defines the board:config to be used.

ifndef BCFG
  $(info ERROR: Board configuration not set)
  $(error Build stopped, BCFG required.)
endif

# BDIR variable sets the board directory.
# It can be implied if the build starts from the board directory.

BDIR ?= ${CURDIR}
ifeq ($(realpath ${BDIR}/configs/${BCFG}),)
  $(error Build stopped, BDIR:BCFG config invalid)
endif

# Control build verbosity
#
#  V=0:   Exit silent mode
#  V=1,2: Enable echo of commands
#  V=2:   Enable bug/verbose options in tools and scripts

ifeq ($(V),)
  MAKE := $(MAKE) -s --no-print-directory
endif

ifeq ($(V),1)
  export Q :=
else ifeq ($(V),2)
  export Q :=
else
  export Q := @
endif

# Kconfiglib the only option

.PHONY: menuconfig savedefconfig oldconfig olddefconfig defconfig genconfig

KCONFIG_CONFIG = ${NXOUT}/.config
KCONFIG_AUTOHEADER = ${NXOUT}/config.h

KCONFIG_ENV := KCONFIG_CONFIG=${KCONFIG_CONFIG}
KCONFIG_ENV += KCONFIG_AUTOHEADER=${KCONFIG_AUTOHEADER}
KCONFIG_ENV += ARCH=${ARCH}

KCONFIG_OLDCONFIG     	= oldconfig
KCONFIG_OLDDEFCONFIG  	= olddefconfig
KCONFIG_MENUCONFIG    	= menuconfig
KCONFIG_SAVEDEFCONFIG 	= savedefconfig
KCONFIG_GENCONFIG		= genconfig
KCONFIG_DEFCONFIG     	= defconfig

.PHONY: ${KCONFIG_CONFIG}
${KCONFIG_CONFIG}:
	$(Q) [ -f ${KCONFIG_CONFIG} ] || \
	${KCONFIG_ENV} ${KCONFIG_DEFCONFIG} ${BDIR}/configs/${BCFG}/defconfig

.PHONY: ${KCONFIG_AUTOHEADER}
${KCONFIG_AUTOHEADER}:
	$(Q) ${KCONFIG_ENV} ${KCONFIG_GENCONFIG}

menuconfig: ${KCONFIG_CONFIG}
	$(Q) ${KCONFIG_ENV} ${KCONFIG_MENUCONFIG}

savedefconfig:
	$(Q) ${KCONFIG_ENV} ${KCONFIG_SAVEDEFCONFIG}

oldconfig:
	$(Q) ${KCONFIG_ENV} ${KCONFIG_OLDCONFIG}

olddefconfig:
	$(Q) ${KCONFIG_ENV} ${KCONFIG_OLDDEFCONFIG}

defconfig:
	$(Q) ${KCONFIG_ENV} ${KCONFIG_DEFCONFIG}

genconfig: ${KCONFIG_CONFIG}
	$(Q) ${KCONFIG_ENV} ${KCONFIG_GENCONFIG}

############################################################################
# Here starts the rules definition for building NuttX libraries
############################################################################
include ${KCONFIG_CONFIG}

MAKE_INC := -f ${KCONFIG_CONFIG}
MAKE_INC += -f ${NXBASE}/tools/Config.mk

.PHONY: libarch 
TARGETS := libarch
libarch: ${KCONFIG_CONFIG} ${KCONFIG_AUTOHEADER}
	$(Q) ${MAKE} ${MAKE_INC} -f Makefile -C arch/${ARCH} all



ifeq (${CONFIG_AUDIO},y)
.PHONY: libaudio
TARGETS += libaudio
libaudio: ${KCONFIG_CONFIG} ${KCONFIG_AUTOHEADER}
	$(Q) ${MAKE} ${MAKE_INC} -f Makefile -C audio all
endif

ifeq (${CONFIG_CRYPTO},y)
.PHONY: libcrypto
TARGETS += libcrypto
libcrypto: ${KCONFIG_CONFIG} ${KCONFIG_AUTOHEADER}
	$(Q) ${MAKE} ${MAKE_INC} -f Makefile -C crypto all
endif

.PHONY: libbinfmt
TARGETS += libbinfmt
libbinfmt: ${KCONFIG_CONFIG} ${KCONFIG_AUTOHEADER}
	$(Q) ${MAKE} ${MAKE_INC} -f Makefile -C binfmt all

# Support for ROMFS image creation

ifeq (${CONFIG_FS_ROMFS},y)
  ifdef ROMFSIMG
    TARGETS += ${ROMFSIMG}
  else
    $(error ROMFSIMG is not defined by the board Makefile)
  endif
endif