Hi Kory, > Am 17.02.2026 um 10:36 schrieb Kory Maincent <[email protected]>: > > On Tue, 17 Feb 2026 09:58:04 +0100 > H. Nikolaus Schaller <[email protected]> wrote: > >> Hi Kory, >> >>> Am 16.02.2026 um 16:11 schrieb Kory Maincent <[email protected]>: >>> >>>>>>> >>>>>>>>> Am 12.02.2026 um 16:26 schrieb Kory Maincent (TI) >>>>>>>>> <[email protected]>: >>>>>>>>> >>>>>>>>> Allow overlays to be applied to any DTB. This adds around ~40% to the >>>>>>>>> total size of the DTB files on average. >>> >>> Yes, I will move on to this solution for now to avoid too many complaints >>> about the devicetree size increases. >> >> I have done some experimentation with this patch (on top of v6.19 and our >> private defconfig) but could not find any DTB size increase. >> >> Does it require another patch or CONFIG change? > > No, but maybe you had already the "DTC_FLAGS=-@" option enabled while building > you image. > This options add the "__symbols__" node listing the symbols to the built > devicetree: > $ fdtdump arch/arm/boot/dts/ti/omap/am335x-bonegreen-eco.dtb 2>/dev/null | > grep symbols
Yes, indeed there is a __symbols__ node in all .dtb I have checked. With make V=1 (on v6.19.0 + some local extensions) I see ./scripts/dtc/dtc -o arch/arm/boot/dts/ti/omap/am335x-bonegreen.dtb -b 0 -iarch/arm/boot/dts/ti/omap/ -i./scripts/dtc/include-prefixes -Wno-interrupt_provider --symbol -Wno-unique_unit_address -Wno-unit_address_vs_reg -Wno-avoid_unnecessary_addr_size -Wno-alias_paths -Wno-graph_child_address -Wno-simple_bus_reg -Wno-unique_unit_address -Wno-unit_address_vs_reg -Wno-avoid_unnecessary_addr_size -Wno-alias_paths -Wno-graph_child_address -Wno-interrupt_map -Wno-simple_bus_reg -d arch/arm/boot/dts/ti/omap/.am335x-bonegreen.dtb.d.dtc.tmp arch/arm/boot/dts/ti/omap/.am335x-bonegreen.dtb.dts.tmp So --symbol is already included, even without your patch. With your patch I see: ./scripts/dtc/dtc -o arch/arm/boot/dts/ti/omap/am335x-bonegreen.dtb -b 0 -iarch/arm/boot/dts/ti/omap/ -i./scripts/dtc/include-prefixes -@ -Wno-interrupt_provider --symbol -Wno-unique_unit_address -Wno-unit_address_vs_reg -Wno-avoid_unnecessary_addr_size -Wno-alias_paths -Wno-graph_child_address -Wno-simple_bus_reg -Wno-unique_unit_address -Wno-unit_address_vs_reg -Wno-avoid_unnecessary_addr_size -Wno-alias_paths -Wno-graph_child_address -Wno-interrupt_map -Wno-simple_bus_reg -d arch/arm/boot/dts/ti/omap/.am335x-bonegreen.dtb.d.dtc.tmp arch/arm/boot/dts/ti/omap/.am335x-bonegreen.dtb.dts.tmp Here we have -@ and --symbol (synonyms for dtc). Well, I finally could trace it down to a malicious infection of our LetuxOS tree by some ODROID kernel patch to scripts/Makefile.lib (0ac84640f12c). That patch globally modifies the DTC_FLAGS mechanism and permanently adds --symbol instead of adding -@ in the arch/board specific Makefile like you propose here. So now I know why I didn't see any increase in size (because it was never reduced). With removing this I now get 67179 bytes as default for am335x-bonegreen.dtb. And with your patch I get (back) to 94260 bytes so I can confirm a 40.3% increase. Please proceed as planned (I don't think it necessarily has to be limited to motherboards with an expansion card system, although that would be a good indication of its usefulness), and thank you for bringing our local issue to my attention. BR and thanks, Nikolaus
