Hi Giulio, On Thu, 14 Oct 2021 at 21:06, Giulio Benetti <giulio.bene...@benettiengineering.com> wrote: > > Hi Simon, > > > Il giorno 15 ott 2021, alle ore 02:53, Simon Glass <s...@chromium.org> ha > > scritto: > > > > Hi Giulio, > > > >> On Thu, 14 Oct 2021 at 15:12, Giulio Benetti > >> <giulio.bene...@benettiengineering.com> wrote: > >> > >> Hi Simon, > >> > >> Il giorno 14 ott 2021, alle ore 22:43, Simon Glass <s...@chromium.org> ha > >> scritto: > >> > >> Hi Giulio, > >> > >> On Thu, 14 Oct 2021 at 13:23, Giulio Benetti > >> <giulio.bene...@benettiengineering.com> wrote: > >> > >> > >> Hi Simon, > >> > >> > >> Il giorno 14 ott 2021, alle ore 20:24, Simon Glass <s...@chromium.org> ha > >> scritto: > >> > >> > >> Hi, > >> > >> > >> On Thu, 14 Oct 2021 at 07:46, Tom Rini <tr...@konsulko.com> wrote: > >> > >> > >> On Thu, Oct 14, 2021 at 02:53:30AM +0200, Giulio Benetti wrote: > >> > >> > >> Hello All, > >> > >> > >> is there a way to pass a dts file without touching the > >> arch/arm/boot/dts/Makefile? > >> > >> > >> On Buildroot we support the possibility to pass an external dts by copying > >> it to the uboot sources to > >> > >> be built but since uboot version 2020.01 it doesn’t work anymore. > >> > >> > >> So I’ve proposed a patch to prepend the dts file in the Makefile above, > >> but this has drawbacks, like we reconfigure(it keeps adding files every > >> time). > >> > >> > >> So I ask you, is there a more canonical way already to achieve this? > >> > >> > >> Not exactly, and it's something we're very much actively discussing > >> > >> right now. > >> > >> > >> Are you using 'make DEVICE_TREE=xxx' ? > >> > >> > >> Yes but it doesn’t work if you don’t add an entry into > >> arch/arm/dts/Makefile > >> > >> Before version 2020.01 worked, but not after it. > >> > >> > >> What board are you building? > >> > >> > >> A20-OLinuXino-Lime_defconfig for but without CONFIG_DEFAULT_DEVICE_TREE > >> undefined, > >> so if you try to pass DEVICE_TREE= pointing to an external .dts file > >> copied to arch/arm/dts/ make doesn’t find the entry in Makefile and it > >> can’t build it. > >> > >> This is useful in build systems like Buildroot where you can provide an > >> external defconfig as well as an external .dts file. > >> > >> So here the solution I see is to create an entry in arch/arm/dts/Makefile > >> on the top of the file afte copying the .dts file we want to build. > >> But on Buildroot they’ve pointed me to ask upstream(here) if there’s a > >> more canonical way or to work together to achieve the goal: > >> > >> https://patchwork.ozlabs.org/project/buildroot/patch/20210209201303.195093-1-giulio.bene...@benettiengineering.com/ > > > > How about not disabling CONFIG_DEFAULT_DEVICE_TREE ? That should work OK. > > But if I’m not wrong the problem of the dts/Makefile remains. If .dts file is > not assigned to dtb-y it won’t be built. > > And in the case of Buildroot we have 2 ways to use external dts files: > 1) patch uboot adding the dts and the entry in dts/Makefile > 2) copy .dts file(let’s say located in ~/my-folder/my.dts) to > arch/arm/dts/my.dts and prepend > the dtb-y += my.dts in arch/arm/dts/Makefile and here problem arises. > Because it can work once but we need to make it possible to have ‘make > uboot-rebuild/reconfigure’ > (Buildroot has such targets). This way is not easy at all to prepend the > dtb-y at the top of the file without re-prepending it again and again. > > It worked up to uboot < 2020.01, but I still haven’t bisected to see the > “offending” commit. > Maybe I can try and find out why it behaves like that. > > What about that?
Have you tried EXT_DTB? It looks like DEVICE_TREE is designed for changing the name of the file. EXT_DTB=/tmp/b/sandbox/u-boot.dtb CROSS_COMPILE=/home/sglass/.buildman-toolchains/gcc-9.2.0-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi- make O=/tmp/b/snow -j30 snow_defconfig all You need to compile it first though. For your case, I did a bisect with: git bisect run make -s DEVICE_TREE=try CROSS_COMPILE=/home/sglass/.buildman-toolchains/gcc-9.2.0-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi- O=/tmp/b/snow -j30 mrproper snow_defconfig all and got: a3444bd09af (refs/bisect/bad) Revert "Ensure device tree DTS is compiled" +Masahiro Yamada who might know BTW if you rely on this feature, once it is working again, we should add a test for it. Regards, Simon
