diff --git a/cmake/BBBCrossCompileConfig.cmake b/cmake/BBBCrossCompileConfig.cmake new file mode 100644 index 0000000..4af5686 --- /dev/null +++ b/cmake/BBBCrossCompileConfig.cmake @@ -0,0 +1,98 @@ +# BBB_ROOTFS should point to the local directory which contains all the +# libraries and includes from the target raspi. +# The following command can be used to do this, replace and the +# local accordingly: +# rsync -vR --progress -rl --delete-after --safe-links pi@:/{lib,usr,opt/vc/lib} +# RASPBIAN_ROOTFS needs to be passed to the CMake command or defined in the +# application CMakeLists.txt before loading the toolchain file. + +# CROSS_COMPILE also needs to be set accordingly or passed to the CMake command + +if(NOT DEFINED ENV{BBB_ROOTFS}) + message(FATAL_ERROR + "Define the BBB_ROOTFS variable to point to the Beagle Bone Black rootfs." + ) +else() + set(SYSROOT_PATH "$ENV{BBB_ROOTFS}") + message(STATUS "Beagle Bone Black sysroot: ${SYSROOT_PATH}") +endif() + +if(NOT DEFINED ENV{CROSS_COMPILE}) + set(CROSS_COMPILE "arm-linux-gnueabihf") + message(STATUS + "No CROSS_COMPILE environmental variable set, using default ARM linux " + "cross compiler name ${CROSS_COMPILE}" + ) +else() + set(CROSS_COMPILE "$ENV{CROSS_COMPILE}") + message(STATUS + "Using environmental variable CROSS_COMPILE as cross-compiler: " + "$ENV{CROSS_COMPILE}" + ) +endif() + +message(STATUS "Using sysroot path: ${SYSROOT_PATH}") + +set(CROSS_COMPILE_CC "${CROSS_COMPILE}-gcc") +set(CROSS_COMPILE_CXX "${CROSS_COMPILE}-g++") +set(CROSS_COMPILE_LD "${CROSS_COMPILE}-ld") +set(CROSS_COMPILE_AR "${CROSS_COMPILE}-ar") +set(CROSS_COMPILE_RANLIB "${CROSS_COMPILE}-ranlib") +set(CROSS_COMPILE_STRIP "${CROSS_COMPILE}-strip") +set(CROSS_COMPILE_NM "${CROSS_COMPILE}-nm") +set(CROSS_COMPILE_OBJCOPY "${CROSS_COMPILE}-objcopy") +set(CROSS_COMPILE_SIZE "${CROSS_COMPILE}-size") + +# At the very least, cross compile gcc and g++ have to be set! +find_program (CROSS_COMPILE_CC_FOUND ${CROSS_COMPILE_CC} REQUIRED) +find_program (CROSS_COMPILE_CXX_FOUND ${CROSS_COMPILE_CXX} REQUIRED) + +set(CMAKE_CROSSCOMPILING TRUE) +set(CMAKE_SYSROOT "${SYSROOT_PATH}") + +# Define name of the target system +set(CMAKE_SYSTEM_NAME "Linux") +set(CMAKE_SYSTEM_PROCESSOR "arm") + +# Define the compiler +set(CMAKE_C_COMPILER ${CROSS_COMPILE_CC}) +set(CMAKE_CXX_COMPILER ${CROSS_COMPILE_CXX}) + +# List of library dirs where LD has to look. Pass them directly through gcc. +# LD_LIBRARY_PATH is not evaluated by arm-*-ld +set(LIB_DIRS + "${SYSROOT_PATH}/lib/${CROSS_COMPILE}" + "${SYSROOT_PATH}/usr/local/lib" + "${SYSROOT_PATH}/usr/lib/${CROSS_COMPILE}" + "${SYSROOT_PATH}/usr/lib" +) +# You can additionally check the linker paths if you add the +# flags ' -Xlinker --verbose' +set(COMMON_FLAGS "-I${SYSROOT_PATH}/usr/include") +foreach(LIB ${LIB_DIRS}) + set(COMMON_FLAGS "${COMMON_FLAGS} -L${LIB} -Wl,-rpath-link,${LIB}") +endforeach() + +set(CMAKE_PREFIX_PATH + "${CMAKE_PREFIX_PATH}" + "${SYSROOT_PATH}/usr/lib/${CROSS_COMPILE}" +) + +set(CMAKE_C_FLAGS + "-march=armv7-a -mtune=cortex-a8 -mfpu=neon -mfloat-abi=softfp ${COMMON_FLAGS}" + CACHE STRING "Flags for Beagle Bone Black" +) +set(CMAKE_CXX_FLAGS "${CMAKE_C_FLAGS}" + CACHE STRING "Flags for Beagle Bone Black" +) + +set(CMAKE_FIND_ROOT_PATH + "${CMAKE_INSTALL_PREFIX};${CMAKE_PREFIX_PATH};${CMAKE_SYSROOT}" +) + +# search for programs in the build host directories +set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER) +# for libraries and headers in the target directories +set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY) +set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY) +set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)