[U-Boot] [PATCH 4/5] kbuild: generate u-boot.cfg as a byproduct of include/autoconf.mk

[Simon Glass]

On 25 September 2016 at 22:05, Masahiro Yamada
<yamada.masahiro at socionext.com> wrote:
> Our build system still parses ad-hoc CONFIG options in header files
> and generates include/autoconf.mk so that Makefiles can reference
> them.  This gimmick was introduced in the pre-Kconfig days and will
> be kept until Kconfig migration is completed.
>
> The include/autoconf.mk is generated like follows:
>
>   [1] Preprocess include/common.h with -DDO_DEPS_ONLY and
>       retrieve macros into include/autoconf.mk.tmp
>   [2] Reformat include/autoconf.mk.dep into include/autoconf.mk
>       with tools/scripts/define2mk.sed script
>   [3] Remove include/autoconf.mk.tmp
>
> Here, include/autoconf.mk.tmp is similar to u-boot.cfg, which is
> also generated by preprocessing include/config.h with -DDO_DEPS_ONLY.
> In other words, there is much overlap among include/autoconf.mk and
> u-boot.cfg build rules.
>
> So, the idea is to split the build rule of include/autoconf.mk
> into two stages.  The first preprocesses headers into u-boot.cfg.
> The second parses the u-boot.cfg into include/autoconf.mk.  The
> build rules of u-boot.cfg in Makefile and spl/Makefile will be gone.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
>
>  Makefile                  | 17 +----------------
>  scripts/Makefile.autoconf | 37 ++++++++++++++++++++++++++-----------
>  scripts/Makefile.spl      | 20 +-------------------
>  3 files changed, 28 insertions(+), 46 deletions(-)

Reviewed-by: Simon Glass <sjg at chromium.org>