[PATCH v4 2/2] kbuild: Use if_changed for font and splash .incbin rules

[Rasmus Villemoes]

On Mon, Apr 13 2026, Simon Glass <sjg at chromium.org> wrote:

> The generated .S files for fonts and splash screens use .incbin with the
> full prerequisite path. When building with O= this bakes an absolute
> path into the .S file. If the build directory is later used on a
> different machine (e.g. in a container), the assembler cannot find the
> source file.
>
> Follow the existing DTB convention: rename the object targets to use
> compound suffixes (.ttf.o, .bmp.o), switch the pattern rules from
> direct $(call cmd,...) to FORCE + $(call if_changed,...), and register
> the new suffixes with intermediate_targets so that kbuild loads their
> .cmd files. This lets if_changed detect when the recorded command
> (including source paths) has changed and regenerate the .S file
> automatically.
>
> The EFI rule is left unchanged since its prerequisite is a generated
> file in the build directory, like the DTB and DTBO rules.
>
> The intermediate_targets entries stay in scripts/Makefile.build rather
> than moving to scripts/Makefile.lib-u-boot, because that file is
> included before intermediate_targets is defined and 'targets' is ':=',
> so a '$(call intermediate_targets, ...)' inside it would expand to
> empty and silently drop the entries. To keep the upstream block
> untouched, the U-Boot additions go in a separate 'targets +=' block
> immediately below.
>
> Suggested-by: Rasmus Villemoes <ravi at prevas.dk>
> Signed-off-by: Simon Glass <sjg at chromium.org>

Reviewed-by: Rasmus Villemoes <ravi at prevas.dk>