Hi Sumit, On Wed, Dec 20, 2023 at 12:01 PM Sumit Garg <sumit.g...@linaro.org> wrote: > > Hi Simon, > > On Wed, 20 Dec 2023 at 10:17, Simon Glass <s...@chromium.org> wrote: > > > > Hi Sumit, > > > > On Thu, 14 Dec 2023 at 06:52, Sumit Garg <sumit.g...@linaro.org> wrote: > > > > > > Allow platform owners to mirror devicetree files from devitree-rebasing > > > directory into dts/arch/$(ARCH) (special case for dts/arch/arm64). Then > > > build then along with any *-u-boot.dtsi file present in arch/$(ARCH)/dts > > > directory. > > > > Also add a new Makefile for arm64. > > I suppose you are referring to dts/arch/arm64/Makefile which has been > added by this patch.
Yes, I just mean that you should mention this in the commit message > > > > > > > > > This will help easy migration for platforms which currently are compliant > > > with upstream Linux kernel devicetree files. > > > > > > Signed-off-by: Sumit Garg <sumit.g...@linaro.org> > > > --- > > > dts/Kconfig | 11 +++++++++++ > > > dts/Makefile | 17 ++++++++++++++--- > > > dts/arch/arm64/Makefile | 14 ++++++++++++++ > > > 3 files changed, 39 insertions(+), 3 deletions(-) > > > create mode 100644 dts/arch/arm64/Makefile > > > > > > diff --git a/dts/Kconfig b/dts/Kconfig > > > index 00c0aeff893..96396f12b67 100644 > > > --- a/dts/Kconfig > > > +++ b/dts/Kconfig > > > @@ -85,6 +85,17 @@ config OF_LIVE > > > enables a live tree which is available after relocation, > > > and can be adjusted as needed. > > > > > > +config OF_UPSTREAM > > > + bool "Enable use of devicetree imported from Linux kernel release" > > > + help > > > + Traditionally, U-boot platforms used to have their custom > > > devicetree > > > > U-Boot > > > > (I think I mentioned this, but you thought I said U-boot...but it > > really is U-Boot). Perhaps grep your patches next time. > > Ah, I see. It looks like I missed that bit, and will take care of it > in the next revision. > > > > > > + files or copy devicetree files from Linux kernel which are hard > > > to > > > + maintain and can usually get out-of-sync from Linux kernel. This > > > + option enables platforms to migrate to devicetree-rebasing repo > > > where > > > + a regular sync will be maintained every major Linux kernel > > > release > > > + cycle. However, platforms can still have some custom u-boot > > > specific > > > + bits maintained as part of *-u-boot.dtsi files. > > > > I'm a bit nervous about this. It means that boards chose between this > > dir of the local files. It means there is some effort to switch. > > > > I wonder if we could default to using the rebasing thing, with boards > > having to 'opt out'? So this should be 'default y' ? > > Ideally that should be our migration path going forward once we get > enough boards migrated to use rebasing repo. But at this initial stage > we have to put some effort on migrating boards to use rebasing > subtree, although effort should be just adding (given DT bindings > compliance) following to defconfig (see patch #7): > > CONFIG_OF_UPSTREAM=y > CONFIG_DEFAULT_DEVICE_TREE="amlogic/meson-gxbb-nanopi-k2" > > and create a mirrored copy of: > ../../../devicetree-rebasing/src/arm64/amlogic/ into > dts/arch/arm64/amlogic/ with modifications to add targets to > dts/arch/arm64/Makefile. > > I am happy to put in that effort but certainly for new board support > that would like to import DT from Linux it should be the default. That > stands true for the Qcom platform series for which Caleb is currently > working on. The problem I see is that this is board-by-board, so will never happen. Changing one board (e.g. rockpro64-rk3399) typically involves changing the .dtsi files it includes (e.g. rk3399.dtsi) so it is hard/impossible to do one board without doing all. So this is why I believe the setting should be on an SoC basis, not on a board basis. > > > > > > > > + > > > choice > > > prompt "Provider of DTB for DT control" > > > depends on OF_CONTROL > > > diff --git a/dts/Makefile b/dts/Makefile > > > index 3437e54033d..8098bf8191a 100644 > > > --- a/dts/Makefile > > > +++ b/dts/Makefile > > > @@ -10,10 +10,20 @@ ifeq ($(DEVICE_TREE),) > > > DEVICE_TREE := unset > > > endif > > > > > > +ifeq ($(CONFIG_OF_UPSTREAM),y) > > > +ifeq ($(CONFIG_ARM64),y) > > > +DEVICE_TREE_LOC := dts/arch/arm64 > > > > dt_dir ? > > Okay I will rename it. > > > > > Should we move the arm64 DTs to arch/arm64 ? > > IMO, the migration path should be to use rebasing subtree via > dts/arch/arm64/ and dropping DTs except *-u-boot.dtsi from > arch/$(ARCH)/dts. So moving DTs from arch/arm/ to arch/arm64/ seems > like a redundant change to me. I can see that argument, but having two different directory structures would be confusing. > > > > > What about the subdirs used in Linux? > > I hope I have described above regarding how subdirs are mirrored. > However, have a look at patch #7 for the amlogic/ subdir example. OK Regards, Simon
