cmake: add ubuntu build for OcPoC hardware

cmake/toolchains/Toolchain-gcc-arm-linux-gnueabihf.cmake

@@ -0,0 +1,74 @@
+# defines:
+#
+# NM
+# OBJCOPY
+# LD
+# CXX_COMPILER
+# C_COMPILER
+# CMAKE_SYSTEM_NAME
+# CMAKE_SYSTEM_VERSION
+# LINKER_FLAGS
+# CMAKE_EXE_LINKER_FLAGS
+# CMAKE_FIND_ROOT_PATH
+# CMAKE_FIND_ROOT_PATH_MODE_PROGRAM
+# CMAKE_FIND_ROOT_PATH_MODE_LIBRARY
+# CMAKE_FIND_ROOT_PATH_MODE_INCLUDE
+
+include(CMakeForceCompiler)
+
+# this one is important
+set(CMAKE_SYSTEM_NAME Generic)
+
+#this one not so much
+set(CMAKE_SYSTEM_VERSION 1)
+
+# specify the cross compiler
+find_program(C_COMPILER arm-linux-gnueabihf-gcc)
+
+if(NOT C_COMPILER)
+	message(STATUS "Make sure to: apt-get install arm-linux-gnueabihf-gcc")
+	message(FATAL_ERROR "could not find arm-linux-gnueabihf-gcc compiler")
+endif()
+cmake_force_c_compiler(${C_COMPILER} GNU)
+
+find_program(CXX_COMPILER arm-linux-gnueabihf-g++)
+
+if(NOT CXX_COMPILER)
+	message(FATAL_ERROR "could not find arm-linux-gnueabihf-g++ compiler")
+endif()
+cmake_force_cxx_compiler(${CXX_COMPILER} GNU)
+
+# compiler tools
+foreach(tool objcopy nm ld)
+	string(TOUPPER ${tool} TOOL)
+	find_program(${TOOL} arm-linux-gnueabihf-${tool})
+	if(NOT ${TOOL})
+		message(FATAL_ERROR "could not find arm-linux-gnueabihf-${tool}")
+	endif()
+endforeach()
+
+# os tools
+foreach(tool echo grep rm mkdir nm cp touch make unzip)
+	string(TOUPPER ${tool} TOOL)
+	find_program(${TOOL} ${tool})
+	if(NOT ${TOOL})
+		message(FATAL_ERROR "could not find ${TOOL}")
+	endif()
+endforeach()
+
+set(LINKER_FLAGS "-Wl,-gc-sections")
+set(CMAKE_EXE_LINKER_FLAGS ${LINKER_FLAGS})
+set(CMAKE_C_FLAGS ${C_FLAGS})
+set(CMAKE_CXX_LINKER_FLAGS ${C_FLAGS} -mfloat-abi=hard -mcpu=cortex-a9 -mfpu=neon-vfpv3 -O3 -funsafe-math-optimizations -mthumb-interwork -ftree-vectorize)
+
+# where is the target environment
+set(CMAKE_FIND_ROOT_PATH  get_file_component(${C_COMPILER} PATH))
+
+# 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)
+
+# enable static linking
+#set(LDFLAGS "--disable-shared")