Re: [PATCH V7 4/6] kbuild: Add support to build overlays (%.dtbo)

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Viresh,

On Wed, Mar 3, 2021 at 6:21 AM Viresh Kumar <viresh.kumar@linaro.org> wrote:
> On 24-02-21, 19:32, Frank Rowand wrote:
> > I overlooked this and mistakenly thought that the move to .dtbo also
> > involved changing to .dtso.  My bad.
> >
> > My favorite color here is to use .dtso for the source file that will
> > be compiled to create a .dtbo.
> >
> > Linus has already accepted patch 4/6 to 5.12-rc1, so changing to .dtso
> > will require another patch.
>
> Looks like this is what many people desire, lets do it and make it a
> standard even if it wasn't followed earlier.
>
> What about this ?

Thanks, looks good to me, and works for me, so
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -337,7 +337,7 @@ $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
>
>  quiet_cmd_dtc = DTC     $@
>  cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
> -       $(DTC) -O $(patsubst .%,%,$(suffix $@)) -o $@ -b 0 \
> +       $(DTC) -I dts -O $(patsubst .%,%,$(suffix $@)) -o $@ -b 0 \
>                 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
>                 -d $(depfile).dtc.tmp $(dtc-tmp) ; \
>         cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
> @@ -348,6 +348,9 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
>  $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
>         $(call if_changed_dep,dtc)
>
> +$(obj)/%.dtbo: $(src)/%.dtso $(DTC) FORCE
> +       $(call if_changed_dep,dtc)
> +
>  overlay-y := $(addprefix $(obj)/, $(overlay-y))
>
>  quiet_cmd_fdtoverlay = DTOVL   $@
> @@ -373,6 +376,9 @@ endef
>  $(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
>         $(call if_changed_rule,dtc,yaml)
>
> +$(obj)/%.dt.yaml: $(src)/%.dtso $(DTC) $(DT_TMP_SCHEMA) FORCE

I'm wondering if "dt.yaml" should be changed to "dto.yaml" (here and in
the existing rule earlier in Makefile.lib), to avoid issues if both foo.dts and
foo.dtso exist? Unlikely, but it might happen...

> I had to keep the original line as is:
>
>  $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
>
> to support the unittest stuff as there are no dtso files there. There
> are few things we can do here:
>
> - Don't follow the dtso/dtbo convention for unittest, build files as
>   dtb only and everything will continue to work I suppose as
>   fdtoverlay won't complain.
>
> - Keep the above line in Makefile, this doesn't sound right, isn't it
>   ?
>
> - Make .dts links for unittest file, maybe from the Makefile itself.
>
> - Something else ?

Rename unittest .dts files to .dtso where applicable?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds