u-boot/scripts/Makefile.autoconf
Masahiro Yamada e02ee2548a kconfig: switch to single .config configuration
When Kconfig for U-boot was examined, one of the biggest issues was
how to support multiple images (Normal, SPL, TPL).  There were
actually two options, "single .config" and "multiple .config".
After some discussions and thought experiments, I chose the latter,
i.e. to create ".config", "spl/.config", "tpl/.config" for Normal,
SPL, TPL, respectively.

It is true that the "multiple .config" strategy provided us the
maximum flexibility and helped to avoid duplicating CONFIGs among
Normal, SPL, TPL, but I have noticed some fatal problems:

[1] It is impossible to share CONFIG options across the images.
  If you change the configuration of Main image, you often have to
  adjust some SPL configurations correspondingly.  Currently, we
  cannot handle the dependencies between them.  It means one of the
  biggest advantages of Kconfig is lost.

[2] It is too painful to change both ".config" and "spl/.config".
  Sunxi guys started to work around this problem by creating a new
  configuration target.  Commit cbdd9a9737 (sunxi: kconfig: Add
  %_felconfig rule to enable FEL build of sunxi platforms.) added
  "make *_felconfig" to enable CONFIG_SPL_FEL on both images.
  Changing the configuration of multiple images in one command is a
  generic demand.  The current implementation cannot propose any
  good solution about this.

[3] Kconfig files are getting ugly and difficult to understand.
  Commit b724bd7d63 (dm: Kconfig: Move CONFIG_SYS_MALLOC_F_LEN to
  Kconfig) has sprinkled "if !SPL_BUILD" over the Kconfig files.

[4] The build system got more complicated than it should be.
  To adjust Linux-originated Kconfig to U-Boot, the helper script
  "scripts/multiconfig.sh" was introduced.  Writing a complicated
  text processor is a shell script sometimes caused problems.

Now I believe the "single .config" will serve us better.  With it,
all the problems above would go away.  Instead, we will have to add
some CONFIG_SPL_* (and CONFIG_TPL_*) options such as CONFIG_SPL_DM,
but we will not have much.  Anyway, this is what we do now in
scripts/Makefile.spl.

I admit my mistake with my apology and this commit switches to the
single .config configuration.

It is not so difficult to do that:

 - Remove unnecessary processings from scripts/multiconfig.sh
  This file will remain for a while to support the current defconfig
  format.  It will be removed after more cleanups are done.

 - Adjust some makefiles and Kconfigs

 - Add some entries to include/config_uncmd_spl.h and the new file
   scripts/Makefile.uncmd_spl.  Some CONFIG options that are not
   supported on SPL must be disabled because one .config is shared
   between SPL and U-Boot proper going forward.  I know this is not
   a beautiful solution and I think we can do better, but let's see
   how much we will have to describe them.

 - update doc/README.kconfig

More cleaning up patches will follow this.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2015-02-24 17:06:23 -05:00

130 lines
4.1 KiB
Makefile

# This helper makefile is used for creating
# - symbolic links (arch/$ARCH/include/asm/arch
# - include/autoconf.mk, {spl,tpl}/include/autoconf.mk
# - include/config.h
#
# When our migration to Kconfig is done
# (= When we move all CONFIGs from header files to Kconfig)
# this makefile can be deleted.
__all: include/autoconf.mk include/autoconf.mk.dep
ifeq ($(shell grep -q '^CONFIG_SPL=y' include/config/auto.conf 2>/dev/null && echo y),y)
__all: spl/include/autoconf.mk
endif
ifeq ($(shell grep -q '^CONFIG_TPL=y' include/config/auto.conf 2>/dev/null && echo y),y)
__all: tpl/include/autoconf.mk
endif
include include/config/auto.conf
include scripts/Kbuild.include
# Need to define CC and CPP again here in case the top Makefile did not
# include config.mk. Some architectures expect CROSS_COMPILE to be defined
# in arch/$(ARCH)/config.mk
CC = $(CROSS_COMPILE)gcc
CPP = $(CC) -E
include config.mk
UBOOTINCLUDE := \
-Iinclude \
$(if $(KBUILD_SRC), -I$(srctree)/include) \
-I$(srctree)/arch/$(ARCH)/include \
-include $(srctree)/include/linux/kconfig.h
c_flags := $(KBUILD_CFLAGS) $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) \
$(UBOOTINCLUDE) $(NOSTDINC_FLAGS)
quiet_cmd_autoconf_dep = GEN $@
cmd_autoconf_dep = $(CC) -x c -DDO_DEPS_ONLY -M -MP $(c_flags) \
-MQ include/config/auto.conf $(srctree)/include/common.h > $@ || { \
rm $@; false; \
}
include/autoconf.mk.dep: FORCE
$(call cmd,autoconf_dep)
# We are migrating from board headers to Kconfig little by little.
# In the interim, we use both of
# - include/config/auto.conf (generated by Kconfig)
# - include/autoconf.mk (used in the U-Boot conventional configuration)
# The following rule creates autoconf.mk
# include/config/auto.conf is grepped in order to avoid duplication of the
# same CONFIG macros
quiet_cmd_autoconf = GEN $@
cmd_autoconf = \
$(CPP) $(c_flags) $2 -DDO_DEPS_ONLY -dM $(srctree)/include/common.h > $@.tmp && { \
sed -n -f $(srctree)/tools/scripts/define2mk.sed $@.tmp | \
while read line; do \
if ! grep -q "$${line%=*}=" include/config/auto.conf; then \
echo "$$line"; \
fi \
done > $@; \
rm $@.tmp; \
} || { \
rm $@.tmp; false; \
}
include/autoconf.mk: FORCE
$(call cmd,autoconf)
spl/include/autoconf.mk: FORCE
$(Q)mkdir -p $(dir $@)
$(call cmd,autoconf,-DCONFIG_SPL_BUILD)
tpl/include/autoconf.mk: FORCE
$(Q)mkdir -p $(dir $@)
$(call cmd,autoconf,-DCONFIG_SPL_BUILD -DCONFIG_TPL_BUILD)
include/autoconf.mk include/autoconf.mk.dep \
spl/include/autoconf.mk tpl/include/autoconf.mk: include/config.h
# include/config.h
# Prior to Kconfig, it was generated by mkconfig. Now it is created here.
define filechk_config_h
(echo "/* Automatically generated - do not edit */"; \
for i in $$(echo $(CONFIG_SYS_EXTRA_OPTIONS) | sed 's/,/ /g'); do \
echo \#define CONFIG_$$i \
| sed '/=/ {s/=/ /;q; } ; { s/$$/ 1/; }'; \
done; \
echo \#define CONFIG_BOARDDIR board/$(if $(VENDOR),$(VENDOR)/)$(BOARD);\
echo \#include \<config_defaults.h\>; \
echo \#include \<config_uncmd_spl.h\>; \
echo \#include \<configs/$(CONFIG_SYS_CONFIG_NAME).h\>; \
echo \#include \<asm/config.h\>; \
echo \#include \<config_fallbacks.h\>;)
endef
include/config.h: scripts/Makefile.autoconf create_symlink FORCE
$(call filechk,config_h)
# symbolic links
# If arch/$(ARCH)/mach-$(SOC)/include/mach exists,
# make a symbolic link to that directory.
# Otherwise, create a symbolic link to arch/$(ARCH)/include/asm/arch-$(SOC).
PHONY += create_symlink
create_symlink:
ifneq ($(KBUILD_SRC),)
$(Q)mkdir -p include/asm
$(Q)if [ -d $(KBUILD_SRC)/arch/$(ARCH)/mach-$(SOC)/include/mach ]; then \
dest=arch/$(ARCH)/mach-$(SOC)/include/mach; \
else \
dest=arch/$(ARCH)/include/asm/arch-$(if $(SOC),$(SOC),$(CPU)); \
fi; \
ln -fsn $(KBUILD_SRC)/$$dest include/asm/arch
else
$(Q)if [ -d arch/$(ARCH)/mach-$(SOC)/include/mach ]; then \
dest=../../mach-$(SOC)/include/mach; \
else \
dest=arch-$(if $(SOC),$(SOC),$(CPU)); \
fi; \
ln -fsn $$dest arch/$(ARCH)/include/asm/arch
endif
PHONY += FORCE
FORCE:
.PHONY: $(PHONY)