On Wed, 22 Sep 2021 11:13:36 -0700 Trent Piepho <trent.piepho@xxxxxxxxxxxxxxxxx> wrote: Hi! This patch was applied to barebox source tree as 2ae7ac7ab2 kbuild: dtc: Allow adding device tree fragments via config With this patch I see build error if device tree file name starts with digit (0-9), e.g.: barebox$ git checkout v2022.01.0 barebox$ make mrproper barebox$ export ARCH=arm barebox$ export CROSS_COMPILE=arm-none-eabi- barebox$ sed -i "s/virt2real.dtb/2virt2real.dtb/" arch/arm/dts/Makefile barebox$ mv arch/arm/dts/virt2real.dts arch/arm/dts/2virt2real.dts barebox$ make virt2real_defconfig ... barebox$ make -s <stdin>:1:9: error: macro names must be identifiers make[1]: [scripts/Makefile.lib:352: arch/arm/dts/2virt2real.dtb] Error 1 make: [Makefile:952: arch/arm/dts] Error 2 > This introduces a config variable that allows adding additional fragments > to the Barebox device tree(s). > > Example uses are adjusting the flash partition layout, adding barebox > state variables, or adding an I2C device. These can be now be done with > build configuration only, without needing to patch the existing dts > files in the Barebox source. > > The advantage is greater when an external build system, such as Yocto or > Buildroot, is being used to build Barebox. The build system can drop in > a dts fragment to partition flash and build from unaltered Barebox > source. This avoids the need for cumbersome maintenance of patch files > to modify Barebox's source for each flash partition layout. > > Preprocessing the dts file gains another layer, where a generated dts > source consisting of an include directive for the original dts source is > followed by more includes for each fragment. This is piped to the > existing preprocessor call on stdin to avoid another temporary file. > cpp/dtc will correctly identify errors in the source files they occur > in. The -MT option is used so the cpp auto-dependencies reference the > original dts source and not the generated code passed on stdin. > > A preprocessor macro named after the base dts file, e.g. foo-bar.dts > will define foo_bar_dts, will be defined so that the fragments can > possibly operate differently based on which image's dts is being built. > > Signed-off-by: Trent Piepho <trent.piepho@xxxxxxxxxxxxxxxxx> > --- > Changes from v1: > - Remove 2nd config variable for in-tree fragments. > - Add macro to preproccessed dts > > common/Kconfig | 18 ++++++++++++++++++ > scripts/Makefile.lib | 8 +++++++- > 2 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/common/Kconfig b/common/Kconfig > index a9feae2ae..6fdc14148 100644 > --- a/common/Kconfig > +++ b/common/Kconfig > @@ -1091,6 +1091,24 @@ config SYSTEMD_OF_WATCHDOG > in the kernel device tree. If the kernel is booted without a device > tree or with one that lacks aliases, nothing is added. > > +config EXTERNAL_DTS_FRAGMENTS > + string "external dts file fragments" > + depends on OFTREE > + help > + List of dts fragment files that will be appended to Barebox's device > + tree(s) source when building the dtb file(s). If multiple files are > + listed, they will be appended in order. Relative filenames will use > + the dtc include search path. > + > + A preprocessor macro based on the name of the main dts will be > + defined, which allows the dts fragments to based on which image of a > + multi image build they are being used in. > + > + It not intended that this be put into into Barebox defconfig files. > + Instead, it's an external build system, like Yocto or buildroot, to > + add dts fragments from outside the Barebox source tree into the > + Barebox build. > + > menu "OP-TEE loading" > > config OPTEE_SIZE > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index 80d76b177..4496f1a70 100644 > --- a/scripts/Makefile.lib > +++ b/scripts/Makefile.lib > @@ -201,6 +201,7 @@ cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(__cpp_flags) > ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) > > dtc_cpp_flags = -Wp,-MD,$(depfile).pre -nostdinc \ > + -Wp,-MT,$(basename $(notdir $@)).o \ > -I$(srctree)/arch/$(SRCARCH)/dts/include \ > -I$(srctree)/dts/include \ > -I$(srctree)/include \ > @@ -335,8 +336,13 @@ cmd_dt_S_dtb = $(srctree)/scripts/gen-dtb-s $(subst -,_,$(*F)) $< $(CONFIG_IMD) > $(obj)/%.dtb.S: $(obj)/%.dtb $(srctree)/scripts/gen-dtb-s FORCE > $(call if_changed,dt_S_dtb) > > +dts-frags = $(subst $(quote),,$(CONFIG_EXTERNAL_DTS_FRAGMENTS)) > quiet_cmd_dtc = DTC $@ > -cmd_dtc = $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ > +# For compatibility between make 4.2 and 4.3 > +H := \# > +cmd_dtc = /bin/echo -e '$(H)define $(subst -,_,$(*F))_dts 1\n'$(foreach f,$< $(dts-frags),'$(H)include "$(f)"\n') | \ > + $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) - ; \ > $(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 \ > -i $(srctree)/arch/$(SRCARCH)/dts $(DTC_FLAGS) \ > -i $(srctree)/dts/src/$(SRCARCH) \ > -- > 2.31.1 > > > _______________________________________________ > barebox mailing list > barebox@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/barebox -- Best regards, Antony Pavlov _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
