On 12/16/17 09:25, Andre Heider wrote: > Hi Frank, > > On 15/12/17 22:06, Frank Rowand wrote: >> On 12/14/17 07:12, Andre Heider wrote: >>> The overlay feature requires the base dtb to be built with symbols, so >>> lets build the dtbs with symbols when overlay support was explicitly >>> enabled. >>> >>> With CONFIG_OF_ALL_DTBS on ARCH=arm the 989 dtb files grow about ~38% on >>> average. >>> >>> Totals in bytes with the 3 biggest ones: >>> >>> Before: >>> 90471 arch/arm/boot/dts/am57xx-beagle-x15-revc.dtb >>> 90521 arch/arm/boot/dts/am57xx-beagle-x15-revb1.dtb >>> 92639 arch/arm/boot/dts/dra7-evm.dtb >>> 25731296 total >>> >>> After: >>> 133203 arch/arm/boot/dts/am57xx-beagle-x15-revc.dtb >>> 133237 arch/arm/boot/dts/am57xx-beagle-x15-revb1.dtb >>> 134545 arch/arm/boot/dts/dra7-evm.dtb >>> 35464440 total >>> >>> Signed-off-by: Andre Heider <a.heider@xxxxxxxxx> >>> --- >>> >>> Hi, >>> >>> while playing around with overlays I noticed that I needed to rebuilt >>> my distro's device trees because they didn't come with symbols. >>> >>> Is that for a reason, maybe the not so minor increase in size? >> >> Yes, size is the issue. >> >> >>> >>> Thanks, >>> Andre >>> >>> drivers/of/unittest-data/Makefile | 7 ------- >>> scripts/Makefile.lib | 5 +++++ >>> 2 files changed, 5 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/of/unittest-data/Makefile b/drivers/of/unittest-data/Makefile >>> index 32389acfa616..b65061013512 100644 >>> --- a/drivers/of/unittest-data/Makefile >>> +++ b/drivers/of/unittest-data/Makefile >>> @@ -15,13 +15,6 @@ targets += overlay.dtb overlay.dtb.S >>> targets += overlay_bad_phandle.dtb overlay_bad_phandle.dtb.S >>> targets += overlay_bad_symbol.dtb overlay_bad_symbol.dtb.S >>> targets += overlay_base.dtb overlay_base.dtb.S >>> - >>> -# enable creation of __symbols__ node >>> -DTC_FLAGS_overlay := -@ >>> -DTC_FLAGS_overlay_bad_phandle := -@ >>> -DTC_FLAGS_overlay_bad_symbol := -@ >>> -DTC_FLAGS_overlay_base := -@ >>> - >>> endif >>> .PRECIOUS: \ >> >> No. The unittests require these to be set unconditionally. >> >> >>> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib >>> index 1ca4dcd2d500..c7ba4aa8a07a 100644 >>> --- a/scripts/Makefile.lib >>> +++ b/scripts/Makefile.lib >>> @@ -278,6 +278,11 @@ DTC_FLAGS += -Wnode_name_chars_strict \ >>> -Wproperty_name_chars_strict >>> endif >>> +ifeq ($(CONFIG_OF_OVERLAY),y) >>> +# enable creation of __symbols__ node >>> +DTC_FLAGS += -@ >>> +endif >>> + >>> DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) >>> # Generate an assembly file to wrap the output of the device tree compiler >>> >> >> Not needed. Instead set DTC_FLAGS in the make command. For example: >> >> DTC_FLAGS=-@ make qcom-apq8074-dragonboard.dtb >> >> There are a few architecture Makefiles that need to be fixed to not unconditionally >> set DTC_FLAGS. > > Rebuilding the dts files manually with symbols isn't the problem. The > idea was to enable it with a switch which distros simply can flip. > > Passing DTC_FLAGS to `make` would work too I guess, but on multi > platform builds that's still the same issue if there're boards which > can't handle that because of the size increase. > > Would a solution which enables symbols per family work? E.g. > CONFIG_MACH_SUN7I chooses to use -@ because it can handle it. > > Thanks, > Andre Making it easy for distros to increase the size of .dtb files is not the correct answer. We are trying to decrease the footprint of devicetree, not increase it. -Frank -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
