Hi.
On Sat, Feb 22, 2020 at 1:12 AM Alexandre Torgue
<alexandre.torgue@xxxxxx> wrote:
>
> This commit adds a new script to create a file (in dts file directory) with
> some information (date, Linux version, user). This file could then be used
> to populate "build-info" property in every dts file that would use this
> build information:
>
> Example:
>
> / {
> ...
> build-info = /incbin/("dtb-build.txt");
> ...
> };
>
> Signed-off-by: Alexandre Torgue <alexandre.torgue@xxxxxx>
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index bae62549e3d2..a5af84ef4ffc 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -246,6 +246,7 @@ quiet_cmd_gzip = GZIP $@
> # DTC
> # ---------------------------------------------------------------------------
> DTC ?= $(objtree)/scripts/dtc/dtc
> +DTB_GEN_INFO ?= $(objtree)/scripts/gen_dtb_build_info.sh
>
> # Disable noisy checks by default
> ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
> @@ -286,6 +287,7 @@ $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
>
> quiet_cmd_dtc = DTC $@
> cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
> + $(DTB_GEN_INFO) $(src) ; \
> $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
> $(DTC) -O $(2) -o $@ -b 0 \
> $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
> diff --git a/scripts/gen_dtb_build_info.sh b/scripts/gen_dtb_build_info.sh
> new file mode 100755
> index 000000000000..0cd8bd98e410
> --- /dev/null
> +++ b/scripts/gen_dtb_build_info.sh
> @@ -0,0 +1,10 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +
> +set -o nounset
> +
> +DTB_DIR=$1
> +DTB_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
> +DTB_INFO="From Linux $KERNELRELEASE by $DTB_COMPILE_BY the $(date).\0"
> +
> +printf "$DTB_INFO" > "$DTB_DIR/dtb-build.txt"
> --
> 2.17.1
>
There are more than 1000 *.dts files
in arch/arm/boot/dts/.
So, with this patch, the build system will creates
arch/arm/boot/dts/dtb-build.txt 1000 times.
Does it work with parallel build ?
Think about what would happen
with 'make -j32 ARCH=arm dtbs'
The 32 threads will write to
arch/arm/boot/dts/dtb-build.txt
at the same time.
Then, some of DTB would very likely to
include the broken dtb-build.txt
A list of missing parts in this approach:
- make it work with parallel build
- clean it up with 'make clean'
- add it .gitignore (and Documentation/dontdiff)
--
Best Regards
Masahiro Yamada
