#   Part of the Raspberry-Pi Bare Metal Tutorials
#   Copyright (c) 2013-2015, Brian Sidebotham
#   All rights reserved.

#   Redistribution and use in source and binary forms, with or without
#   modification, are permitted provided that the following conditions are met:

#   1. Redistributions of source code must retain the above copyright notice,
#       this list of conditions and the following disclaimer.

#   2. Redistributions in binary form must reproduce the above copyright notice,
#       this list of conditions and the following disclaimer in the
#       documentation and/or other materials provided with the distribution.

#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
#   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
#   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
#   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
#   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
#   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
#   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
#   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
#   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
#   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
#   POSSIBILITY OF SUCH DAMAGE.

# A CMake toolchain file so we can cross-compile for the Rapsberry-Pi bare-metal

include(CMakeForceCompiler)

# usage
# cmake -DCMAKE_TOOLCHAIN_FILE=../toolchain-arm-none-eabi.cmake ../

# The Generic system name is used for embedded targets (targets without OS) in
# CMake
set( CMAKE_SYSTEM_NAME          Generic )
set( CMAKE_SYSTEM_PROCESSOR     BCM2835 )

# Set a toolchain path. You only need to set this if the toolchain isn't in
# your system path. Don't forget a trailing path separator!
set( TC_PATH "" )

# The toolchain prefix for all toolchain executables
set( CROSS_COMPILE arm-none-eabi- )

# specify the cross compiler. We force the compiler so that CMake doesn't
# attempt to build a simple test program as this will fail without us using
# the -nostartfiles option on the command line
CMAKE_FORCE_C_COMPILER( ${TC_PATH}${CROSS_COMPILE}gcc GNU )

# We must set the OBJCOPY setting into cache so that it's available to the
# whole project. Otherwise, this does not get set into the CACHE and therefore
# the build doesn't know what the OBJCOPY filepath is
set( CMAKE_OBJCOPY      ${TC_PATH}${CROSS_COMPILE}objcopy
    CACHE FILEPATH "The toolchain objcopy command " FORCE )

# Set the CMAKE C flags (which should also be used by the assembler!

#use hardware floating point
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfloat-abi=hard" )
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mno-unaligned-access" )

#pi1 flags
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv6zk" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mtune=arm1176jzf-s" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=vfp" )

#pi2 flags
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv7-a" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mtune=cortex-a7" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=neon-vfpv4" )

#pi3 flags
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv8-a" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mtune=cortex-a53" )
#set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=crypto-neon-fp-armv8" )

#current flags for all
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv6zk" )
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mtune=arm1176jzf-s" )
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=vfp" )
set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS}" CACHE STRING "" )

set( CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} -march=armv7-a" )
set( CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} -mfpu=neon-vfpv4" )
set( CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS}" CACHE STRING "" )

set( KERNEL_NAME "./kernelrpi.img" )