On Wed, Mar 10, 2021 at 4:09 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> This piece of code converts the target suffix to the dtc -O option:
>
> *.dtb -> -O dtb
> *.dt.yaml -> -O yaml
>
> Commit ce88c9c79455 ("kbuild: Add support to build overlays (%.dtbo)")
> added the third case:
>
> *.dtbo -> -O dtbo
>
> This works thanks to commit 163f0469bf2e ("dtc: Allow overlays to have
> .dtbo extension") in the upstream DTC, which has already been pulled in
> the kernel.
>
> However, I think it is a bit odd because "dtbo" is not a format name.
> At least, it does not show up in the help message of dtc.
>
> $ scripts/dtc/dtc --help
> [ snip ]
> -O, --out-format <arg>
> Output formats are:
> dts - device tree source text
> dtb - device tree blob
> yaml - device tree encoded as YAML
> asm - assembler source
>
> So, I am not a big fan of the second hunk of that change:
>
> } else if (streq(outform, "dtbo")) {
> dt_to_blob(outf, dti, outversion);
>
> Anyway, we did not need to do this in Makefile in the first place.
>
> guess_type_by_name() had already understood ".yaml" before commit
> 4f0e3a57d6eb ("kbuild: Add support for DT binding schema checks"),
> and now does ".dtbo" as well.
>
> Makefile does not need to duplicate the same logic. Let's leave it
> to dtc.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>
> scripts/Makefile.lib | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index eee59184de64..90a4e04cd8f5 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -327,7 +327,7 @@ $(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) -o $@ -b 0 \
> $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
> -d $(depfile).dtc.tmp $(dtc-tmp) ; \
> cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
I think you should also drop 'yaml' from:
$(call if_changed_rule,dtc,yaml)
Though that's somewhat separate, so either way:
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Rob
