Re: [PATCH V10 2/5] kbuild: Add generic rule to apply fdtoverlay

From: Masahiro Yamada <masahiroy@kernel.org>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Michal Marek <michal.lkml@markovi.net>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	David Gibson <david@gibson.dropbear.id.au>,
	Frank Rowand <frowand.list@gmail.com>,
	Michal Simek <michal.simek@xilinx.com>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Anmar Oueja <anmar.oueja@linaro.org>,
	Bill Mills <bill.mills@linaro.org>, Rob Herring <robh@kernel.org>,
	Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH V10 2/5] kbuild: Add generic rule to apply fdtoverlay
Date: Wed, 10 Mar 2021 01:27:58 +0900	[thread overview]
Message-ID: <CAK7LNATebzcDXvdq0K5Y2f7tHw7i0429fDTSga8Qqkd5emjP_g@mail.gmail.com> (raw)
In-Reply-To: <c6dea8f363725c069e26031ec7c7c5f27850103b.1615199908.git.viresh.kumar@linaro.org>

On Mon, Mar 8, 2021 at 7:45 PM Viresh Kumar <viresh.kumar@linaro.org> wrote:
>
> From: Rob Herring <robh@kernel.org>
>
> Add a generic rule to apply fdtoverlay in Makefile.lib, so every
> platform doesn't need to carry the complex rule. This also automatically
> adds "DTC_FLAGS_foo_base += -@" for all base files.
>
> The platform's Makefile only needs to have this now:
>
>  foo-dtbs := foo_base.dtb foo_overlay1.dtbo foo_overlay2.dtbo
>  dtb-y := foo.dtb
>
> We don't want to run schema checks on foo.dtb (as foo.dts doesn't exist)
> and the Makefile is updated accordingly.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Co-developed-by: Viresh Kumar <viresh.kumar@linaro.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Acked-by: Masahiro Yamada <masahiroy@kernel.org>


> ---
>  scripts/Makefile.lib | 26 ++++++++++++++++++++++++--
>  1 file changed, 24 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index a2658242d956..bc045a54a34e 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -75,11 +75,24 @@ always-y += $(userprogs-always-y) $(userprogs-always-m)
>  # If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
>  dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
>
> +# List all dtbs to be generated by fdtoverlay
> +overlay-y := $(foreach m,$(dtb-y), $(if $(strip $($(m:.dtb=-dtbs))),$(m),))
> +
> +# Generate symbols for the base files so overlays can be applied to them.
> +$(foreach m,$(overlay-y), $(eval DTC_FLAGS_$(basename $(firstword $($(m:.dtb=-dtbs)))) += -@))
> +
> +# Add base dtb and overlay dtbo
> +dtb-y += $(foreach m,$(overlay-y), $($(m:.dtb=-dtbs)))
> +
>  always-y                       += $(dtb-y)
>
>  ifneq ($(CHECK_DTBS),)
> -always-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y))
> -always-y += $(patsubst %.dtbo,%.dt.yaml, $(dtb-y))
> +# Don't run schema checks for dtbs created by fdtoverlay as they don't
> +# have corresponding dts files.
> +dt-yaml-y := $(filter-out $(overlay-y),$(dtb-y))
> +
> +always-y += $(patsubst %.dtb,%.dt.yaml, $(dt-yaml-y))
> +always-y += $(patsubst %.dtbo,%.dt.yaml, $(dt-yaml-y))
>  endif
>
>  # Add subdir path
> @@ -337,6 +350,15 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
>  $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
>         $(call if_changed_dep,dtc)
>
> +overlay-y := $(addprefix $(obj)/, $(overlay-y))
> +
> +quiet_cmd_fdtoverlay = DTOVL   $@
> +      cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
> +
> +$(overlay-y): FORCE
> +       $(call if_changed,fdtoverlay)
> +$(call multi_depend, $(overlay-y), .dtb, -dtbs)
> +
>  DT_CHECKER ?= dt-validate
>  DT_BINDING_DIR := Documentation/devicetree/bindings
>  # DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
> --
> 2.25.0.rc1.19.g042ed3e048af
>


-- 
Best Regards
Masahiro Yamada