[ Upstream commit fa714cf58c7c09a454ff9fda2ee8318591128eb6 ]

We are having more and more schema files.

Commit 8b6b80218b01 ("dt-bindings: Fix command line length limit
calling dt-mk-schema") fixed the 'Argument list too long' error of
the schema checks, but the same error happens while cleaning too.

'make clean' after 'make dt_binding_check' fails as follows:

  $ make dt_binding_check
    [ snip ]
  $ make clean
  make[2]: execvp: /bin/sh: Argument list too long
  make[2]: *** [scripts/Makefile.clean:52: __clean] Error 127
  make[1]: *** [scripts/Makefile.clean:66: Documentation/devicetree/bindings] Error 2
  make: *** [Makefile:1763: _clean_Documentation] Error 2

'make dt_binding_check' generates so many .example.dts, .dt.yaml files,
which are passed to the 'rm' command when you run 'make clean'.

I added a small hack to use the 'find' command to clean up most of the
build artifacts before they are processed by scripts/Makefile.clean

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20200625170434.635114-2-masahiroy@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

As the number of schemas has increased, we're starting to hit the error
"execvp: /bin/sh: Argument list too long". This is due to passing all the
schema files on the command line to dt-mk-schema. It currently is only
with out of tree builds and is intermittent depending on the file path
lengths.

Commit 2ba06cd8565b ("kbuild: Always validate DT binding examples") made
hitting this proplem more likely since the example validation now always
gets the full list of schemas.

Fix this by passing the schema file list in a pipe and using xargs. We end
up doing the find twice, but the time is insignificant compared to the
dt-mk-schema time.

Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Rob Herring <robh@kernel.org>

In commit 2ba06cd8565b ("kbuild: Always validate DT binding examples"),
the core schemas (from dtschema repo) were inadvertently disabled for
dtbs_checks. Re-enable them.

Fixes: 2ba06cd8565b ("kbuild: Always validate DT binding examples")
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>

Since commit 93512dad334d ("dt-bindings: Improve validation build error
handling"), 'make dtbs_check' does not validate the schema fully.

If you want to check everything, you need to run two commands separately.

  $ make ARCH=arm dt_binding_check
  $ make ARCH=arm dtbs_check

They are exclusive each other, so you cannot do like this:

  $ make ARCH=arm dt_binding_check dtbs_check

In this case, dt-doc-validate and dt-extract-example are skipped
because CHECK_DTBS is set.

Let's make it possible to run these two targets in a single command.
It will be useful for schema writers.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>

Now that we have a separate rule for DT binding examples, we can customize
the dtc options. Let's adjust the dtc warnings to me more strict by
default so the examples get cleaned up as they get converted to schema.

Leaving 'avoid_unnecessary_addr_size' and 'graph_child_address' warnings
disabled as examples tend to be incomplete and they generates a lot of
warnings.

Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Most folks only run dt_binding_check on the single schema they care about
by setting DT_SCHEMA_FILES. That means example is only checked against
that one schema which is not always sufficient.

Let's address this by splitting processed-schema.yaml into 2 files: one
that's always all schemas for the examples and one that's just the schema
in DT_SCHEMA_FILES for dtbs.

Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Schema errors can cause make to exit before useful information is
printed. This leaves developers wondering what's wrong. It can be
overcome passing '-k' to make, but that's not an obvious solution.
There's 2 scenarios where this happens.

When using DT_SCHEMA_FILES to validate with a single schema, any error
in the schema results in processed-schema.yaml being empty causing a
make error. The result is the specific errors in the schema are never
shown because processed-schema.yaml is the first target built. Simply
making processed-schema.yaml last in extra-y ensures the full schema
validation with detailed error messages happen first.

The 2nd problem is while schema errors are ignored for
processed-schema.yaml, full validation of the schema still runs in
parallel and any schema validation errors will still stop the build when
running validation of dts files. The fix is to not add the schema
examples to extra-y in this case. This means 'dtbs_check' is no longer a
superset of 'dt_binding_check'. Update the documentation to make this
clear.

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Rob Herring <robh@kernel.org>

Commit 837158b847a4 ("dt-bindings: Check the examples against the
schemas") started generating YAML encoded DT files to validate the
examples against the schema. When running 'make dt_binding_check' in
tree after the 1st time, the generated example .dt.yaml files are
mistakenly added to the list of schema files. Exclude *.example.dt.yaml
files from the search for schema files.

Fixes: 837158b847a4 ("dt-bindings: Check the examples against the schemas")
Reported-by: Guido Günther <agx@sigxcpu.org>
Tested-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Rob Herring <robh@kernel.org>

Currently, the binding examples are just built with dtc. dtc recently
gained the support necessary to output the examples in YAML format
(commit 87963ee20693 ("livetree: add missing type markers in generated
overlay properties"). Now just switch the output format and the examples
will be checked against the schema.

Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Rob Herring <robh@kernel.org>

In order to have $ref's to schema files within the kernel, we need to
pass the base path of bindings to the schema validation tools.

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: devicetree@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>