[U-Boot] [RFC PATCH] kbuild: turn of dtc unit address warnings by default

[Bin Meng]

On Mon, Feb 27, 2017 at 2:24 PM, Masahiro Yamada
<yamada.masahiro at socionext.com> wrote:
> DTC 1.4.2 or later checks DT unit-address without reg property and
> vice-versa, and generates lots of warnings.  Fixing DT files will
> take for a while.  Until then, let's turn off the check unless
> building with W=*.
>
> Introduce a new helper dtc-option to check if the option is supported
> in order to suppress warnings on older versions.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
>
> This is one possible answer to Tom's:
> https://www.mail-archive.com/u-boot@lists.denx.de/msg240328.html
>
> He fixed the problem on travis-ci by commit a0f3e3d, but it is still
> annoying during the regular development.
> Perhaps we may want to hide the warnings (at least hidden in Linux
> Kernel by default).
> Or, is it better to keep it noisy
> to motivate people to fix their DT files?
> I am not quite sure...
>
> Now I am sending this as RFC patch in case people may want to start discussion.
>
> BTW, this is a counter-part of the patch I sent to the Kbuild sub-system
> (https://patchwork.kernel.org/patch/9592747/)
> because I want the U-Boot build system with Linux as much as possible.
> Let's see if I will get possible opinions in the Kbuild review.
>
>
>  Makefile                   | 2 +-
>  scripts/Kbuild.include     | 5 +++++
>  scripts/Makefile.extrawarn | 6 ++++++
>  3 files changed, 12 insertions(+), 1 deletion(-)
>

Tested-by: Bin Meng <bmeng.cn at gmail.com>