Re: [PATCH] cmd_dtc: Enable generation of device tree symbols
From: Masahiro Yamada <masahiroy@kernel.org>
Date: 2021-01-25 21:55:57
Also in:
linux-devicetree, linux-kbuild, lkml
On Mon, Jan 25, 2021 at 8:07 PM Uwe Kleine-König [off-list ref] wrote:
Adding the -@ switch to dtc results in the binary devicetrees containing a list of symbolic references and their paths. This is necessary to apply device tree overlays e.g. on Raspberry Pi as described on https://www.raspberrypi.org/documentation/configuration/device-tree.md. Obviously the downside of this change is an increas of the size of the generated dtbs, for an arm out-of-tree build (multi_v7_defconfig): $ du -s arch/arm/boot/dts* 101380 arch/arm/boot/dts-pre 114308 arch/arm/boot/dts-post so this is in average an increase of 12.8% in size. Signed-off-by: Uwe Kleine-König <redacted>
(CCing DT ML.) https://www.spinics.net/lists/linux-kbuild/msg27904.html See Rob's comment: "We've already rejected doing that. Turning on '-@' can grow the dtb size by a significant amount which could be problematic for some boards."
quoted hunk ↗ jump to hunk
--- scripts/Makefile.lib | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 213677a5ed33..0683a5808f7f 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib@@ -319,7 +319,7 @@ $(obj)/%.dtb.S: $(obj)/%.dtb FORCE quiet_cmd_dtc = DTC $@ cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ - $(DTC) -O $(patsubst .%,%,$(suffix $@)) -o $@ -b 0 \ + $(DTC) -@ -O $(patsubst .%,%,$(suffix $@)) -o $@ -b 0 \ $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ -d $(depfile).dtc.tmp $(dtc-tmp) ; \ cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) --2.29.2
-- Best Regards Masahiro Yamada _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel