Re: [RFC PATCH v2 0/4] Add device tree build information

Alexandre Torgue
2020-03-31T15:01:46Z

Hi Steeve

On 3/31/20 3:03 AM, Steve McIntyre wrote:
> Hi Alexandre,
>
> On Mon, Mar 02, 2020 at 01:55:55PM +0100, Alexandre Torgue wrote:
>> On 2/28/20 6:47 PM, Frank Rowand wrote:
>>>> This would require modifying every single main .dts file to get the build info
>>>> I would prefer the method that Ian and David came up with (sorry, no lore link,
>>>> it did not go to lkml). Extract from David's email:
>>>>
>>>> Date: Tue, 21 Jan 2020 13:05:25 +1100
>>>> From: David Gibson <david@gibson.dropbear.id.au>
>>>> Subject: Re: [RFC PATCH 1/3] dtc: Add dtb build information option
>>>>
>>>> > Given that dts files are run through the C preprocessor before being
>>>> > fed to dtc, the build script could use the '-include' flag to force-
>>>> > include a fragment containing generated build info without any need to
>>>> > modify existing dts files.
>>>>
>>>> Uh... maybe. -include will essentially prepend the forced file, which
>>>> is a bit awkward for our purposes. It means that the prepended file
>>>> would need the /dts-v1/ tag, and we couldn't have it in the main files
>>>> which would be a bit confusing. I think it would also cause problems
>>>> with any /memreserve/ tags and means that the main tree could in
>>>> theory overwrite the build information which we don't necessarily
>>>> want.
>>>>
>>>> I guess we could build things the other way around: have the main .dts
>>>> file specified with -include and have the dts on the dtc commandline
>>>> be a fixed one with the build information. It'd be a little weird,
>>>> though.
>>>>
>>>> -Frank
>>
>> Yes. I try briefly this idea but I got issues with dts-v1 tag. I agree, it is
>> cleaner to not modify input dts file. I can rework int this way.
>
> Have you made any progress on this please?

Unfortunately no. I cook something locally but not yet upstream-able.
Due to project issue I didn't find time to work on it. I think (I hope)
to be less busy next week and so I'll restart it.

regards
alex

>
> Cheers,
>