通过DEFINE 生存config.h 配置

DEFINES += \
   BOARD=$(PROJECT) \
   PROJECT_$(PROJECT)=1 \
   TARGET_$(TARGET)=1 \
   PLATFORM_$(PLATFORM)=1 \
   ARCH_$(ARCH)=1 \
   $(addsuffix =1,$(addprefix WITH_,$(ALLMODULES)))

# debug build?
ifneq ($(DEBUG),)
DEFINES += \
   DEBUG=$(DEBUG)
endif

ALLOBJS := $(addprefix $(BUILDDIR)/,$(ALLOBJS))

DEPS := $(ALLOBJS:%o=%d)

# default to no ccache
CCACHE ?=
CC := $(CCACHE) $(TOOLCHAIN_PREFIX)gcc
LD := $(TOOLCHAIN_PREFIX)ld
OBJDUMP := $(TOOLCHAIN_PREFIX)objdump
OBJCOPY := $(TOOLCHAIN_PREFIX)objcopy
CPPFILT := $(TOOLCHAIN_PREFIX)c++filt
SIZE := $(TOOLCHAIN_PREFIX)size
NM := $(TOOLCHAIN_PREFIX)nm

# comment out or override if you want to see the full output of each command
NOECHO ?= @

# the logic to compile and link stuff is in here
include make/build.mk

clean: $(EXTRA_CLEANDEPS)
   rm -f $(ALLOBJS) $(DEPS) $(GENERATED) $(OUTBIN) $(OUTELF) $(OUTELF).lst

spotless:
   rm -rf build-*

install: all
   scp $(OUTBIN) 192.168.0.4:/tftproot

# generate a config.h file with all of the DEFINES laid out in #define format
configheader:

$(CONFIGHEADER): configheader
   @$(MKDIR)
   @echo generating $@
   @rm -f $(CONFIGHEADER).tmp; \
   echo \#ifndef __CONFIG_H > $(CONFIGHEADER).tmp; \
   echo \#define __CONFIG_H >> $(CONFIGHEADER).tmp; \
   for d in `echo $(DEFINES) | tr [:lower:] [:upper:]`; do \
       echo "#define $$d" | sed "s/=/\ /g;s/-/_/g;s/\//_/g" >> $(CONFIGHEADER).tmp; \
   done; \
   echo \#endif >> $(CONFIGHEADER).tmp; \
   if [ -f "$(CONFIGHEADER)" ]; then \
       if cmp "$(CONFIGHEADER).tmp" "$(CONFIGHEADER)"; then \
           rm -f $(CONFIGHEADER).tmp; \
       else \
           mv $(CONFIGHEADER).tmp $(CONFIGHEADER); \
       fi \
   else \
       mv $(CONFIGHEADER).tmp $(CONFIGHEADER); \
   fi