[PATCH] Makefile: Fix include directory for OF_UPSTREAM

[Sumit Garg]

On Wed, 29 May 2024 at 14:45, Patrick Barsanti
<patrick.barsanti at amarulasolutions.com> wrote:
>
> Hi Sumit,
>
> On Wed, 29 May 2024 at 08:57, Sumit Garg <sumit.garg at linaro.org> wrote:
>>
>> Hi Patrick,
>>
>> On Tue, 28 May 2024 at 14:16, Patrick Barsanti
>> <patrick.barsanti at amarulasolutions.com> wrote:
>> >
>> > Always prioritizing u-boot includes causes problems when trying to
>> > migrate boards to OF_UPSTREAM that have divergent devicetree files with
>> > respect to the upstream ones.
>> >
>> > For example, migrating a board based on `imx6ul.dtsi` to OF_UPSTREAM
>> > breaks it, as there are some missing defines in the local dtsi file;
>> > the solutions would be to either patch it, which defeats the purpose of
>> > OF_UPSTREAM, or delete it entirely. This last option would then break all
>> > the other boards which have not yet been migrated to OF_UPSTREAM.
>>
>> Can you elaborate more here regarding which dt-bindings headers
>> conflict? Also, is it only the DTS files consumer for those headers or
>> there are U-Boot drivers depending on them too?
>>
>> -Sumit
>
>
> Sorry, I think I have worded my commit message wrong. I should
> have used differ instead of diverge, which is slightly misleading.
>
> The specific case I am talking about can be found in:
> include/dt-bindings/clock/imx6ul-clock.h
> dts/upstream/include/dt-bindings/clock/imx6ul-clock.h
>
> The local header is missing the last commit from the kernel, which is
> 4e197ee880c2 ("clk: imx6ul: add ethernet refclock mux support").
> This added some new defines, which are not present in the u-boot
> header.
> Following this commit, the `imx6ul.dtsi` was patched in the kernel to
> use one of the new defines.
>
> Because of this, at the current state, migrating a board which is
> somehow based on `imx6ul.dtsi` will give a dtc error given by a value
> being used in the upstream dtsi which is not defined in the local
> header, because local includes always have priority with respect
> to upstream ones even when setting OF_UPSTREAM.

So you should just drop the local DT bindings header:
include/dt-bindings/clock/imx6ul-clock.h and that should resolve the
problem for you, right?

-Sumit

>
> Regards,
> Patrick
>
>>
>> >
>> > The opposite problem also exists: by always prioritizing upstream
>> > includes, if changes are made in the kernel headers and devicetree
>> > files that are not backwards compatible, again all boards which have not
>> > been migrated to OF_UPSTREAM will break.
>> >
>> > This patch fixes this problem by prioritizing upstream includes when
>> > `CONFIG_OF_UPSTREAM=y`, while keeping current prioritization when
>> > it is not.
>> >
>> > Signed-off-by: Patrick Barsanti <patrick.barsanti at amarulasolutions.com>
>> > ---
>> >  Makefile | 14 ++++++++++++++
>> >  1 file changed, 14 insertions(+)
>> >
>> > diff --git a/Makefile b/Makefile
>> > index 79b28c2d81..899ae664ca 100644
>> > --- a/Makefile
>> > +++ b/Makefile
>> > @@ -826,6 +826,19 @@ KBUILD_HOSTCFLAGS += $(if $(CONFIG_TOOLS_DEBUG),-g)
>> >
>> >  # Use UBOOTINCLUDE when you must reference the include/ directory.
>> >  # Needed to be compatible with the O= option
>> > +ifeq ($(CONFIG_OF_UPSTREAM),y)
>> > +UBOOTINCLUDE    := \
>> > +       -I$(srctree)/dts/upstream/include \
>> > +       -Iinclude \
>> > +       $(if $(KBUILD_SRC), -I$(srctree)/include) \
>> > +       $(if $(CONFIG_$(SPL_)SYS_THUMB_BUILD), \
>> > +               $(if $(CONFIG_HAS_THUMB2), \
>> > +                       $(if $(CONFIG_CPU_V7M), \
>> > +                               -I$(srctree)/arch/arm/thumb1/include), \
>> > +                       -I$(srctree)/arch/arm/thumb1/include)) \
>> > +       -I$(srctree)/arch/$(ARCH)/include \
>> > +       -include $(srctree)/include/linux/kconfig.h
>> > +else
>> >  UBOOTINCLUDE    := \
>> >         -Iinclude \
>> >         $(if $(KBUILD_SRC), -I$(srctree)/include) \
>> > @@ -837,6 +850,7 @@ UBOOTINCLUDE    := \
>> >         -I$(srctree)/arch/$(ARCH)/include \
>> >         -include $(srctree)/include/linux/kconfig.h \
>> >         -I$(srctree)/dts/upstream/include
>> > +endif
>> >
>> >  NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
>> >
>> > --
>> > 2.43.0
>> >