| Message ID | 20171214151240.14555-1-a.heider@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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@gmail.com> > --- > > 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. -Frank
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@gmail.com> >> --- >> >> 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
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@gmail.com> >>> --- >>> >>> 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
On 18/12/17 23:10, Frank Rowand wrote: > 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@gmail.com> >>>> --- >>>> >>>> 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. I'm not sure I follow. If it's not acceptable to increase the size, why's there overlay support in the first place? There're distros/downstreams that support overlays today, like armbian, beaglebone and rpi. All carrying their own patches to enable symbols [1] [2] [3] and I'm sure others will follow. Why can't there be some sort of switch for those to build their dtbs with symbols? Regards, Andre [1] https://github.com/armbian/build/blob/master/patch/kernel/sunxi-next/add-overlay-compilation-support.patch#L98 [2] https://github.com/beagleboard/linux/commit/ed6b9450c2a2ec21149f14ff24770b69888abda6 [3] https://github.com/raspberrypi/linux/blob/rpi-4.15.y/arch/arm/boot/dts/Makefile#L1124
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: \ 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
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@gmail.com> --- 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? Thanks, Andre drivers/of/unittest-data/Makefile | 7 ------- scripts/Makefile.lib | 5 +++++ 2 files changed, 5 insertions(+), 7 deletions(-)