Since commit 4b0bcfa7c4ec (Kconfig: Migrate CONFIG_BOOTM_* options),
the config_defaults.h file has been void of any actual content - and
these days, "sane defaults for everyone" is achieved by appropriate
default values in Kconfig. Remove it, and thus make every translation
unit process one less header file.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

Allow to use define CONFIG_IS_ENABLED
in include/config_fallbacks.h

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>

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@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

I do not remember why I wrote the code like this, but let's make it
a bit more readable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

A general best practice for SPDX is that Makefiles should have an
identifier, add these as everything else is currently covered.

Signed-off-by: Tom Rini <trini@konsulko.com>

The symbolic link to SoC/CPU specific header directory is created
during the build, while it is only necessary for ARM, AVR32, SPARC,
x86, and some CPUs of PowerPC.  For the other architectures, it just
results in a broken symbolic link.

Introduce CONFIG_CREATE_ARCH_SYMLINK to not create unneeded symbolic
links.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

When moving configs, it is important to know what was defined in the
config header even if it duplicates the configs coming from Kconfig.

This is specifically needed for the case where a config is set to
default 'y' in the Kconfig. This would previously cause the actual value
from the include config to be filtered out, and moveconfig.py would
think that it was 'n'... This means that the value that should be 'y'
is now (in every defconfig) set to 'not set'.

tools/moveconfig.py now defines KCONFIG_IGNORE_DUPLICATES to prevent the
filtering from happening and selecting wrong values for the defconfig.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>

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 cbdd9a9737cc (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 b724bd7d6349 (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>

In U-Boot, SoC-specific headers are placed in
arch/$(ARCH)/include/asm/arch-$(SOC) and a symbolic link to that
directory is created at the early stage of the build process.

Creating and removing a symbolic link during the build is not
preferred.  In fact, Linux Kernel did away with include/asm-$(ARCH)
directories a long time time ago.

As for ARM, now it is possible to collect SoC sources into
arch/arm/mach-$(SOC).  It is also reasonable to move SoC headers
into arch/arm/mach-$(SOC)/include/mach.

This commit prepares for that.
If the directory arch/$(ARCH)/mach-$(SOC)/include/mach exists,
a symbolic to that directory is created.  Otherwise, a symbolic link
to arch/$(ARCH)/include/asm/arch-$(SOC) or arch-$(CPU) is created.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>