Re: [PATCH] Reapply "kbuild: Create directory for target DTB"

[Matthias Schiffer]

On Tue, 2023-12-12 at 17:13 +0000, Masahiro Yamada wrote:
> 
> 
> On Wed, Dec 13, 2023 at 1:17 AM Matthias Schiffer
> <matthias.schiffer@xxxxxxxxxxxxxxx> wrote:
> > 
> > This reverts commit dd7699e37f289fa433f42c6bcc108468c8b198c0.
> > 
> > On powerpc, dtb-y is usually empty unless CONFIG_OF_ALL_DTBS is set. While
> > passing a DTB as a make target explicitly works fine, individual DTB
> > builds may also be pulled in as dependencies by cuImage.% and similar
> > targets. In this case, nothing creates the arch/powerpc/dts directory,
> > causing out-of-tree builds to fail.
> > 
> > Fixes: dd7699e37f28 ("Revert "kbuild: Create directory for target DTB"")
> > Signed-off-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx>
> > ---
> 
> 
> 
> NACK.
> 
> %.dtb is generated by if_changed_dep.
> 
> Each Makefile is responsible for adding %.dtb to 'targets'
> if it is pulled in as dependencies of other images.
> 
> If it does not work for PowerPC, it is a bug in PowerPC Makefile.
> 
> 
> Just checking arch/powerpc/boot/Makefile,
> it adds dts/%.dtb and dts/fsl/%.dtb to 'targets'. [1] [2]
> 
> cuImage.% should be file, but it does not cover all images.
> 
> Fix arch/powerpc/boot/Makefile.

Ah, thank you for the pointers, I did not quite get the meaning of those Makefile lines when first
reading them. So the issue is that I'm trying to build a cuImage that is not added to image-y in the
powerpc Makefile. It is unfortunate that this leads to a very confusing error message about the
missing dts directory.

I'll send a new patch if I come to the conclusion that I actually need the cuImage (for the ancient
TQM5200 which hasn't really been touched since 2011).

Regards,
Matthias


> 
> 
> 
> [1] https://github.com/torvalds/linux/blob/v6.7-rc5/arch/powerpc/boot/Makefile#L386
> [2] https://github.com/torvalds/linux/blob/v6.7-rc5/arch/powerpc/boot/Makefile#L388
> 
> 
> 
> >  scripts/Makefile.lib | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> > index 1a965fe68e011..3fe0fc46badfe 100644
> > --- a/scripts/Makefile.lib
> > +++ b/scripts/Makefile.lib
> > @@ -389,7 +389,8 @@ $(obj)/%.dtbo.S: $(obj)/%.dtbo FORCE
> >         $(call if_changed,wrap_S_dtb)
> > 
> >  quiet_cmd_dtc = DTC     $@
> > -cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
> > +cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
> > +       $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
> >         $(DTC) -o $@ -b 0 \
> >                 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
> >                 -d $(depfile).dtc.tmp $(dtc-tmp) ; \
> > --
> > TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany
> > Amtsgericht München, HRB 105018
> > Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
> > https://www.tq-group.com/
> > 
> 
> 
> --
> Best Regards
> 
> Masahiro Yamada
> 

-- 
TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany
Amtsgericht München, HRB 105018
Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
https://www.tq-group.com/