On Mon, Mar 07, 2022 at 01:20:29PM +0100, Geert Uytterhoeven wrote:
> Hi Rob,
>
> On Thu, Mar 3, 2022 at 11:43 PM Rob Herring <robh@xxxxxxxxxx> wrote:
> > Switch the DT validation to use DTB files directly instead of a DTS to
> > YAML conversion.
> >
> > The original motivation for supporting validation on DTB files was to
> > enable running validation on a running system (e.g. 'dt-validate
> > /sys/firmware/fdt') or other cases where the original source DTS is not
> > available.
> >
> > The YAML format was not without issues. Using DTBs with the schema type
> > information solves some of those problems. The YAML format relies on the
> > DTS source level information including bracketing of properties, size
> > directives, and phandle tags all of which are lost in a DTB file. While
> > standardizing the bracketing is a good thing, it does cause a lot of
> > extra warnings and churn to fix them.
> >
> > Another issue has been signed types are not validated correctly as sign
> > information is not propagated to YAML. Using the schema type information
> > allows for proper handling of signed types. YAML also can't represent
> > the full range of 64-bit integers as numbers are stored as floats by
> > most/all parsers.
> >
> > The DTB validation works by decoding property values using the type
> > information in the schemas themselves. The main corner case this does
> > not work for is matrix types where neither dimension is fixed. For
> > now, checking the dimensions in these cases are skipped.
> >
> > Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
>
> Thanks for your patch!
>
> While investigating why a newly added device node to DTS was not
> instantiated as a platform device, I discovered an issue with this
> patch: "make dtbs" no longer rebuilds DTB files that need a rebuild.
>
> How to reproduce:
>
> $ git checkout next-20220307
> # apply this series and its dependency:
> # dt-bindings: kbuild: Support partial matches with DT_SCHEMA_FILES
> # dt-bindings: kbuild: Pass DT_SCHEMA_FILES to dt-validate
> # dt-bindings: kbuild: Use DTB files for validation
> $ make ARCH=arm shmobile_defconfig
> $ make ARCH=arm dtbs
> $ touch arch/arm/boot/dts/r8a7791.dtsi
> $ make ARCH=arm dtbs
> # The above command does NOT cause:
> # DTC arch/arm/boot/dts/r8a7791-koelsch.dtb
> # DTC arch/arm/boot/dts/r8a7791-porter.dtb
>
> I don't see anything wrong with this patch at first sight, though.
Was this a clean tree?
I think I reproduced it, but then couldn't... But then after a 'make
clean', 'make dtbs' would error out. I think the issue in both cases was
processed-schema.json always a dependency when it should be conditional
on 'dtbs_check'. The patch below fixes that. Can you give it a try too.
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 4629af60160b..9d5320a47ef8 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -349,12 +349,12 @@ $(multi-dtb-y): FORCE
$(call if_changed,fdtoverlay)
$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
+ifneq ($(CHECK_DTBS)$(CHECK_DT_BINDING),)
DT_CHECKER ?= dt-validate
DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),-l $(DT_SCHEMA_FILES),-m)
DT_BINDING_DIR := Documentation/devicetree/bindings
-DT_TMP_SCHEMA ?= $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
+DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
-ifneq ($(CHECK_DTBS)$(CHECK_DT_BINDING),)
quiet_cmd_dtb_check = CHECK $@
cmd_dtb_check = $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true
endif
