[PATCH v3 11/13] Makefile: remove hardcoded device tree source directory

[Sumit Garg]

Hi Neha,

On Tue, 27 Feb 2024 at 13:53, Neha Malcom Francis <n-francis at ti.com> wrote:
>
> Hi Bryan
>
> On 27/02/24 02:49, Bryan Brattlof wrote:
> > Some boards that choose to utilize the OF_UPSTREAM directory for their
> > device tree files will need to specify that directory instead of the
> > traditional arch/$(ARCH)/dts/* path.
> >
> > Include the correct path to the board's dtbs depending on if OF_UPSTREAM
> > is selected or not.
> >
> > Reviewed-by: Sumit Garg <sumit.garg at linaro.org>
> > Signed-off-by: Bryan Brattlof <bb at ti.com>
> > ---
> >   Makefile             | 18 ++++++++++++++----
> >   scripts/Makefile.spl | 17 +++++++++++++----
> >   2 files changed, 27 insertions(+), 8 deletions(-)
> >
> > diff --git a/Makefile b/Makefile
> > index 0f0c7f30d2717..51b57d26857f1 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -1184,6 +1184,16 @@ dt_binding_check: scripts_dtc
> >   quiet_cmd_copy = COPY    $@
> >         cmd_copy = cp $< $@
> >
> > +ifeq ($(CONFIG_OF_UPSTREAM),y)
> > +ifeq ($(CONFIG_ARM64),y)
>
> This would fail in case of R5 builds, is there any reason why you choose not to
> use OF_UPSTREAM for R5 builds?

Although I will let Bryan elaborate more here, the essence here is
that OF_UPSTREAM=y means that the target DTS files come from
dts/upstream/src/<arch>/.

>
> I understand that R5 builds will require U-Boot DTS (from U-Boot code base) that
> (ideally) should inherit the kernel core DTS (from upstream), is this support
> not there at present? Let me know if I understand incorrectly.
>

However, with OF_UPSTREAM=n you can have U-Boot DTS placed in
arch/$(ARCH)/dts/ like the R5 case but you can include whatever common
pieces required from dts/upstream/src/<arch>/.

-Sumit

> > +dt_dir := dts/upstream/src/arm64
> > +else
> > +dt_dir := dts/upstream/src/$(ARCH)
> > +endif
> > +else
> > +dt_dir := arch/$(ARCH)/dts
> > +endif
> > +
> >   ifeq ($(CONFIG_MULTI_DTB_FIT),y)
> >
> >   ifeq ($(CONFIG_MULTI_DTB_FIT_LZO),y)
> > @@ -1209,7 +1219,7 @@ endif
> >
> >   MKIMAGEFLAGS_fit-dtb.blob = -f auto -A $(ARCH) -T firmware -C none -O u-boot \
> >       -a 0 -e 0 -E \
> > -     $(patsubst %,-b arch/$(ARCH)/dts/%.dtb,$(subst ",,$(CONFIG_OF_LIST))) -d /dev/null
> > +     $(patsubst %,-b $(dt_dir)/%.dtb,$(subst ",,$(CONFIG_OF_LIST))) -d /dev/null
> >
> >   MKIMAGEFLAGS_fit-dtb.blob += -B 0x8
> >
> > @@ -1407,9 +1417,9 @@ MKIMAGEFLAGS_u-boot.img = -f auto -A $(ARCH) -T firmware -C none -O u-boot \
> >       -a $(CONFIG_TEXT_BASE) -e $(CONFIG_SYS_UBOOT_START) \
> >       -p $(CONFIG_FIT_EXTERNAL_OFFSET) \
> >       -n "U-Boot $(UBOOTRELEASE) for $(BOARD) board" -E \
> > -     $(patsubst %,-b arch/$(ARCH)/dts/%.dtb,$(subst ",,$(DEVICE_TREE))) \
> > -     $(patsubst %,-b arch/$(ARCH)/dts/%.dtb,$(subst ",,$(CONFIG_OF_LIST))) \
> > -     $(patsubst %,-b arch/$(ARCH)/dts/%.dtbo,$(subst ",,$(CONFIG_OF_OVERLAY_LIST)))
> > +     $(patsubst %,-b $(dt_dir)/%.dtb,$(subst ",,$(DEVICE_TREE))) \
> > +     $(patsubst %,-b $(dt_dir)/%.dtb,$(subst ",,$(CONFIG_OF_LIST))) \
> > +     $(patsubst %,-b $(dt_dir)/%.dtbo,$(subst ",,$(CONFIG_OF_OVERLAY_LIST)))
> >   else
> >   MKIMAGEFLAGS_u-boot.img = -A $(ARCH) -T firmware -C none -O u-boot \
> >       -a $(CONFIG_TEXT_BASE) -e $(CONFIG_SYS_UBOOT_START) \
> > diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl
> > index 407fc52376a50..d074ba2350065 100644
> > --- a/scripts/Makefile.spl
> > +++ b/scripts/Makefile.spl
> > @@ -559,9 +559,15 @@ FORCE:
> >   $(obj)/dts/dt-$(SPL_NAME).dtb: dts/dt.dtb
> >       $(Q)$(MAKE) $(build)=$(obj)/dts spl_dtbs
> >
> > -PHONY += dts_dir
> > -dts_dir:
> > -     $(shell [ -d $(obj)/dts ] || mkdir -p $(obj)/dts)
> > +ifeq ($(CONFIG_OF_UPSTREAM),y)
> > +ifeq ($(CONFIG_ARM64),y)
> > +dt_dir := dts/upstream/src/arm64
> > +else
> > +dt_dir := dts/upstream/src/$(ARCH)
> > +endif
> > +else
> > +dt_dir := arch/$(ARCH)/dts
> > +endif
> >
> >   # Declare the contents of the .PHONY variable as phony.  We keep that
> >   # information in a variable so we can use it in if_changed and friends.
> > @@ -569,8 +575,11 @@ dts_dir:
> >
> >   SPL_OF_LIST_TARGETS = $(patsubst %,dts/%.dtb,$(subst ",,$(CONFIG_SPL_OF_LIST)))
> >   SHRUNK_ARCH_DTB = $(addprefix $(obj)/,$(SPL_OF_LIST_TARGETS))
> > +$(dir $(SHRUNK_ARCH_DTB)):
> > +     $(shell [ -d $@ ] || mkdir -p $@)
> > +
> >   .SECONDEXPANSION:
> > -$(SHRUNK_ARCH_DTB): $$(patsubst $(obj)/dts/%, arch/$(ARCH)/dts/%, $$@) dts_dir
> > +$(SHRUNK_ARCH_DTB): $$(patsubst $(obj)/dts/%, $(dt_dir)/%, $$@) $(dir $(SHRUNK_ARCH_DTB))
> >       $(call if_changed,fdtgrep)
> >
> >   targets += $(SPL_OF_LIST_TARGETS)
> >
>
> --
> Thanking You
> Neha Malcom Francis