[RFC PATCH 0/1] Categorize ARM dts directory

[Rob Herring]

On Tue, Mar 29, 2022 at 8:27 AM Ansuel Smith <ansuelsmth at gmail.com> wrote:
>
> On Tue, Mar 29, 2022 at 03:20:18PM +0200, Krzysztof Kozlowski wrote:
> > On 28/03/2022 02:09, Ansuel Smith wrote:
> > > Hi,
> > > as the title say, the intention of this ""series"" is to finally categorize
> > > the ARM dts directory in subdirectory for each oem.
> > >
> > > The main reason for this is that it became unpractical to handle 2600
> > > dts files and try to even understand/edit/check the situation for a
> > > specific target.
> > >
> > > In arm64 we already have this kind of separation and I honestly think
> > > that this was never proposed for ARM due to the fact that there are
> > > 2600+ files to sort and the fact that it will be a mess to merge this
> > > entirely but IMHO with a little bit of effort we can finally solve this
> > > problem and have a well organized directory just like arm64.
> > >
> > > Some prerequisite on how this work was done:
> > > - This comes entirely from a python script created by me for the task.
> > >   linked here [1]
> > > - I had to manually categorize all the different arch in the makefile
> > >   based on the oem. I searched every arch on the internet trying to
> > >   understand the correct oem. I hope they are correct but I would love
> > >   some comments about them.
> > > - This current ""series"" is all squashed in one big commit to better
> > >   receive comments for this. The final version ideally would have all
> > >   changes in separate commits. The script can already do this, it's just
> > >   commented.
> > >
> > > Here is a list of some discoveries while doing all the sorting.
> > > These are totally additional reason why we need this.
> > >
> > > While creating the script I discovered some funny things:
> > > - We have orphan dts! There are dts that are never compiled and are
> > >   there just for reference. We would never have noticed this without this
> > >   change and probably nobody noticed it. They are currently all listed
> > >   in the python script.
> > > - We have dtsi shared across different oem. My current solution for them
> > >   is: NOT SORT THEM and leave them in the generic directory and create a
> > >   link in each oem dts that points to these dtsi. This is to try in
> > >   every way possible to skip any additional changes to the dts.
> > >   Current dtsi that suffers from this are only 3. (listed in the script)
> > > - arm64 dts and dtsi reference ARM dts. Obviously this change would cause
> > >   broken include for these special dtsi. The script creates a dependency
> > >   table of the entire arm64 directory and fix every broken dependency
> > >   (hoping they all use a sane include logic... regex is used to parse
> > >   all the different dependency)
> > >
> > > So in short the script does the following steps:
> > > 1. Enumerate all the action to do... (dts to move, scan dependency for
> > >    the dts...)
> > > 2. Generate the arm64 dependency
> > > 3. Creates the Makefile
> > > 4. Generate the Makefiles for the current oem
> > > 5. Move all the related dts and dtsi for the current oem
> > > 6. Check broken dependency and fix them by editing the dts and writing
> > >    the correct include (or fix any symbolic link)
> > >
> > > This is an output that describes all the things done by the script [2]
> > >
> > > I really hope I didn't commit any logic mistake in the script but most
> > > of the work should be done.
> > >
> >
> > +Cc Arnd and Olof,
> >
> > Ansuel,
> > Thanks for you patch. Please cc the SoC maintainers in such submissions.
> > It seems that you got some quite nice discussion, but still the core
> > folks are not Cced, so no one would be able to take your patch...
> >
>
> I had some problem with gmail and sending mail too much users. I put Rob
> and You and all the various list to try to workaround the "gmail spam
> protection"
>
> > I am pretty sure we were discussing such split idea in the past and it
> > did not get traction, but I cannot recall the exact discussion.
> >
>
> I think the main issue here is how to handle bot and how problematic is
> to merge this. As written in the cover letter the final version of this
> should be a big series of 50+ patch with every commit specific to each
> oem. In theory we should be able to merge the different oem separately
> and try to at least start the categorization.
> Another idea I got to at least have a "migration path" is to convert
> every dts in the dts/ directory to a symbolic link that target the dts
> in the correct oem. But I assume that would fix only part of the problem
> and git am will still be problematic.

I have a script[1] that does the conversion written the last time this
came up. Just have to agree on directory names. I think the easiest
would be for Arnd/Olof to run it at the end of a merge window before
rc1.

I'm very much in favor of this happening especially before *any*
overlays are added to add to the mess (it's probably already
happened).

Rob

[1] https://lore.kernel.org/all/20181204183649.GA5716@bogus/