On Thu, 7 Dec 2023 at 02:12, Rob Herring <robh...@kernel.org> wrote: > > On Tue, Dec 5, 2023 at 11:05 PM Sumit Garg <sumit.g...@linaro.org> wrote: > > > > On Tue, 5 Dec 2023 at 15:39, Krzysztof Kozlowski > > <krzysztof.kozlow...@linaro.org> wrote: > > > > > > On 05/12/2023 10:45, Sumit Garg wrote: > > > > + U-boot custodians list > > > > > > > > On Tue, 5 Dec 2023 at 12:58, Krzysztof Kozlowski > > > > <krzysztof.kozlow...@linaro.org> wrote: > > > >> > > > >> On 05/12/2023 08:13, Sumit Garg wrote: > > > >>>>> @DT bindings maintainers, > > > >>>>> > > > >>>>> Given the ease of maintenance of DT bindings within Linux kernel > > > >>>>> source tree, I don't have a specific objection there. But can we > > > >>>>> ease > > > >>>>> DTS testing for firmware/bootloader projects by providing a > > > >>>>> versioned > > > >>>>> release package for DT bindings? Or if someone else has a better > > > >>>>> idea > > > >>>>> here please feel free to chime in. > > > >>>> > > > >>>> This doesn't work for you?: > > > >>>> > > > >>>> https://git.kernel.org/pub/scm/linux/kernel/git/devicetree/devicetree-rebasing.git/ > > > >>> > > > >>> Thanks, this is certainly a good step which I wasn't aware of. Further > > > >>> simplification can be done to decouple devicetree source files from DT > > > >>> bindings. > > > >> > > > >> Why? > > > > > > > > I suppose you are already aware that Linux DTS files are a subset of > > > > what could be supported by devicetree schemas. There can be > > > > firmware/bootloader specific properties (one example being [1]) which > > > > Linux kernel can simply ignore. Will you be willing to add all of > > > > those DT properties to Linux DTS files and maintain them? > > > > > > We already added them and we already maintain them. DTS describes the > > > hardware, not the OS-subset of the hardware. > > > > Let look at some numbers if your statement is justified or not for the > > example I gave: > > > > u-boot$ git grep -nr bootph-* arch/arm* | wc -l > > 4079 > > > > linux$ git grep -nr bootph-* arch/arm* | wc -l > > 267 > > I have no control over whether anyone has submitted the other 3812 instances. > > > It looks like there is always going to be a catch up game regarding DT > > properties which either Linux kernel or u-boot or any other > > firmware/bootloader project don't care about. > > As long as dts files in u-boot are manually sync'ed, yes. That is the > problem and it doesn't matter if we have a standalone repository or > not. > > If you want to move in that direction, start automating what u-boot > imports. You need to do that for bindings if you want to run > validation, so why not dts files too? > > > > > However, DT bindings are something which should be common, the > > > > hardware description of a device should be universal. IMO, splitting > > > > > > Both DT bindings and DTS should be common. I don't see the difference. > > > > If we really care about DTS to be common then the contribution model > > has to change where there is a single repo hosting DT bindings and > > DTS. All other projects whether it is Linux kernel or u-boot or any > > other OS/firmware/bootloader are just consuming DTS files from that > > single repo. > > Really, only the kernel and u-boot matter. No, I don't mean I don't > care about other projects, but those are the 2 with the widest h/w > support by far and which have a major effort to sync copies of dts > files in both projects. The rest are just noise in terms of this > problem. > > > I suppose this is something that Linux DT maintainers > > have objected to in the past for ease of maintenance. I am not sure if > > you folks are willing to change that stance. > > The issue is no one steps up to help maintain such a repository while > there is lots of review and maintainer work on what goes into the > kernel tree. I'm happy to direct my binding review attention to > wherever the majority of the bindings go. But the work on the DTS side > is mostly SoC tree maintainers and sub-maintainers. > > Assume for a minute we have this standalone repo. What happens next? > We start with an empty repo and then merge and move platforms 1 by 1? > How many years will that take? What do we do with platforms no one is > interested in moving? Or do we start with devicetree-rebasing instead > (That was the plan at one time) and sync u-boot back to that?
Thanks Rob for sharing further insights. So I have given this approach a try here [1]. Lets see how it can serve u-boot community needs and thereby bring DT bindings compliance in u-boot. U-boot community, maintainers, custodians, Feel free to play out with this DT bindings compliance idea here [1] and let us know if this approach helps to reduce DT maintainence burden alongside increasing compliance. [1] https://github.com/u-boot/u-boot/pull/451 -Sumit > > All the work needed to get u-boot and kernel dts files in sync has > virtually no dependency on a standalone repo. If the dts files aren't > already kept in sync, someone has to figure the differences and > eliminate them. Maybe some platforms are in good shape, but it is > still a manual process. Fix that part, because a standalone repo does > nothing for you until you do. > > > > > DT bindings alone would ease the compliance process for u-boot drivers > > > > in quite similar manner to Linux drivers. > > There's no compliance of drivers really beyond checking if compatible > strings used by drivers have a schema. > > Why is extracting the bindings out a problem? SystemReady has no issue > doing just that for its compliance test. > > Rob
