Commit Graph

2 Commits

Author SHA1 Message Date
Rasmus Villemoes
6923f49d3a scripts/Makefile.dts: tweak logic for deciding which dtbs to build
The idea in 3609e1dc5f (dts: automatically build necessary .dtb
files) was fine, but the implementation was suboptimal due to some
misunderstandings on my part (and possibly defects in some defconfig
files):

- Sometimes DEFAULT_DEVICE_TREE is not included in OF_LIST or
  SPL_OF_LIST

- SPL_OF_LIST is not always a subset of OF_LIST

- While SPL_OF_LIST governs the list of dtbs relevant to SPL (i.e.,
  may be built into an
  SPL-with-bunch-of-dtbs-to-choose-between-at-runtime), those dtbs are
  not actually _built_ during the SPL build phase, i.e. when $(SPL_)
  would expand to SPL_. fdtgrep runs on the artifacts produced during
  the ordinary U-Boot build.

Tweak the logic so that we simply add the union of all dtbs mentioned
in either DEFAULT_DEVICE_TREE, OF_LIST and SPL_OF_LIST to dtb-y. That
should, for real, ensure that we always build all the dtbs that is
relevant to the current board, and should in turn enable us to
massively simplify arch/*/dts/Makefile.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Tested-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2023-05-15 14:08:44 -04:00
Rasmus Villemoes
3609e1dc5f dts: automatically build necessary .dtb files
When building for a custom board, it is quite common to maintain a
private branch which include some defconfig and .dts files. But to
hook up those .dts files requires modifying a file "belonging" to
upstream U-Boot, the arch/*/dts/Makefile. Forward-porting that branch
to a newer upstream then often results in a conflict which, while it
is trivial to resolve by hand, makes it harder to have a CI do "try to
build our board against latest upstream".

The .config usually includes information on precisely what .dtb(s) are
needed, so to avoid having to modify the Makefile, simply add the
files in (SPL_)OF_LIST to dtb-y.

A technicality is that (SPL_)OF_LIST is not always defined, so rework
the Kconfig symbols so that (SPL_)OF_LIST is always defined (when
(SPL_)OF_CONTROL), but only prompted for in the cases which used to be
their "depends on".

nios2 and microblaze already have something like this in their
dts/Makefile, and the rationale in commit 41f59f6853 is similar to
the above. So this simply generalizes existing practice. Followup
patches could remove the logic in those two makefiles, just as there's
potential for moving some common boilerplate from all the
arch/*/dts/Makefile files to the new scripts/Makefile.dts.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Simon Glass <sjg@chromium.org>
2022-02-09 12:26:12 -07:00