On Wed, Sep 5, 2018 at 3:36 PM Frank Rowand <frowand.list@xxxxxxxxx> wrote: > > +cc: devicetree-compiler@xxxxxxxxxxxxxxx > > For context on the device-tree compiler list, this patch is for > the Linux kernel. > > On 09/04/18 01:05, Tero Kristo wrote: > > Add simple support for building DT overlays. This just compiles any > > given .dtso file under the base arch/arm/boot/dts directory into > > a .dtbo. > > > > Signed-off-by: Tero Kristo <t-kristo@xxxxxx> > > --- > > arch/arm/Makefile | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/arm/Makefile b/arch/arm/Makefile > > index d1516f8..ab555a0 100644 > > --- a/arch/arm/Makefile > > +++ b/arch/arm/Makefile > > @@ -339,7 +339,7 @@ $(BOOT_TARGETS): vmlinux > > $(INSTALL_TARGETS): > > $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@ > > > > -%.dtb: | scripts > > +%.dtb %.dtbo: | scripts This will need to change with my rework of the DT build rules[1]. > > $(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $(boot)/dts/$@ > > > > PHONY += dtbs dtbs_install > > > > The idea of adding knowledge of .dtso and .dtbo files to the dtc > compiler, but that idea and the related patches have fallen by > the wayside. > > Current overlay sources and blobs are properly handled by dtc when > they are .dts and .dtb files. > > If the dtc compiler is updated with knowledge of .dtso and .dtbo > then these changes would be needed. At the moment the distinction > of a .dtso and .dtbo is a naming convention that provides a clue > about the intended use of the file. But dtc does not know these > file name extensions, requiring a specific flag to tell dtc to > treat them as .dts or .dtb files. I think the negative outweighs > the positive for this patch. I don't follow what you are proposing. We should decide on a convention though. We shouldn't need .dtso because that is identified with the /plugin/ tag. Distinguishing overlay dtbs with .dtbo seems like a good idea though. Rob [1] https://lkml.org/lkml/2018/8/21/770