cmake:基于MDK(Keil)的Nationstech.N32G45x平台交叉编译工具链定义

@rem ------------------------------------------------------------
@rem set environment variable for N32G45X cross compile
@rem ------------------------------------------------------------

@set PATH=C:\Keil_v5\ARM\ARMCC\bin;%PATH%
@set N32G45X_SDK_PREFIX=E:\mdk\Nationstech.N32G45x_Library.1.1.1

# toolchain for Nationstech.N32G45X
INCLUDE(CMakeForceCompiler)

# This one is important
SET(CMAKE_SYSTEM_NAME Generic)
SET(CMAKE_SYSTEM_PROCESSOR arm)
# Keil armcc编译器安装默认位置
set(_compiler_prefix "C:/Keil_v5/ARM/ARMCC")
if(NOT EXISTS ${_compiler_prefix})
	if(NOT $ENV{CROSS_COMPILER_PREFIX} STREQUAL "")
	    set(_compiler_prefix $ENV{CROSS_COMPILER_PREFIX})
	elseif(CROSS_COMPILER_PREFIX)
	    set(_compiler_prefix ${CROSS_COMPILER_PREFIX})
	else()
		find_program(_armcc_path armcc)
		if(NOT _armcc_path)
			message(FATAL_ERROR "NOT FOUND compiler armcc in system path")
		endif()
		get_filename_component(_bin ${_armcc_path} DIRECTORY )
		get_filename_component(_compiler_prefix ${_bin} DIRECTORY )
	endif()	
endif()
set(_suffix)
if(WIN32)
	set(_suffix .exe)
endif()

# 要求环境变量定义 N32G45X_SDK_PREFIX 以指定 N32G45X SDK的安装位置 
# 或由cmake变量N32G45X_SDK_PREFIX 定义
if(NOT $ENV{N32G45X_SDK_PREFIX} STREQUAL "")
    set(N32G45X_SDK_PREFIX $ENV{N32G45X_SDK_PREFIX})
endif()
if(NOT N32G45X_SDK_PREFIX)
	message(FATAL_ERROR "NOT DEFINE N32G45X SDK PREFIX FOR CROSS COMIPILER")
endif()

# Specify the cross compiler
# 定义编译器名字
SET(CMAKE_C_COMPILER "${_compiler_prefix}/bin/armcc${_suffix}")
SET(CMAKE_CXX_COMPILER "${_compiler_prefix}/bin/armcc${_suffix}")
SET(CMAKE_AR "${_compiler_prefix}/bin/armar${_suffix}" CACHE FILEPATH "Archiver")

# 参考N32G45X SDK 工程文件(.uvprojx)中的编译选项定义CMAKE_C_FLAGS_INIT,CMAKE_CXX_FLAGS_INIT  
UNSET(CMAKE_C_FLAGS_INIT CACHE)
SET(CMAKE_C_FLAGS_INIT "--c99 --cpu=Cortex-M4.fp --apcs=interwork --split_sections -DN32G45X -DUSE_STDPERIPH_DRIVER" CACHE STRING "" FORCE)
UNSET(CMAKE_CXX_FLAGS_INIT CACHE)
SET(CMAKE_CXX_FLAGS_INIT "--cpu=Cortex-M4.fp --apcs=interwork --split_sections -DN32G45X -DUSE_STDPERIPH_DRIVER" CACHE STRING "" FORCE)
UNSET(CMAKE_EXE_LINKER_FLAGS_INIT CACHE)
SET(CMAKE_EXE_LINKER_FLAGS_INIT "" CACHE STRING "" FORCE)
UNSET(CMAKE_AR_FLAGS CACHE)
SET(CMAKE_AR_FLAGS "-p -armcc,-Ospace" CACHE STRING "" FORCE)

# set(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> cr <TARGET> <LINK_FLAGS> <OBJECTS>")
SET(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> ${CMAKE_AR_FLAGS} -o <TARGET> <OBJECTS>" CACHE STRING "C Archive Create")
# set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> cr <TARGET> <LINK_FLAGS> <OBJECTS>")
SET(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> ${CMAKE_AR_FLAGS} -o <TARGET> <OBJECTS>" CACHE STRING "CXX Archive Create")

# Where is the target environment
SET(CMAKE_FIND_ROOT_PATH "${_compiler_prefix}")

# 将 N32G45X SDK 的header文件夹添加到include搜索路径
include_directories(
	"${N32G45X_SDK_PREFIX}/firmware/CMSIS/core/"
	"${N32G45X_SDK_PREFIX}/firmware/CMSIS/device"
	"${N32G45X_SDK_PREFIX}/firmware/n32g45x_algo_lib/inc" 
	"${N32G45X_SDK_PREFIX}/firmware/n32g45x_std_periph_driver/inc" 
	"${N32G45X_SDK_PREFIX}/firmware/n32g45x_usbfs_driver/inc" 
	"${N32G45X_SDK_PREFIX}/projects/n32g45x_EVAL/bsp/inc" 
)

# 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)

unset(_compiler_prefix)