[PATCH v2 2/3] arm: dts: rockchip: Separate rockchip-binman.dtsi

[Quentin Schulz]

Hi Jagan,

On 11/3/22 13:37, Jagan Teki wrote:
> On Thu, 3 Nov 2022 at 15:32, Quentin Schulz
> <quentin.schulz at theobroma-systems.com> wrote:
>>
>> Hi Jagan,
>>
>> On 11/3/22 07:19, Jagan Teki wrote:
>>> rockchip-u-boot.dtsi has the FIT image for the final stage of
>>> binman image creation.
>>>
>>> If the actual binman node is part of this dtsi then there are
>>> build issues to use optee as input to this final stage binman
>>> image since optee is built via another binman image creation
>>> unlike ATF built via tools like make_fit_atf.py.
>>>
>>>      binman: Filename 'u-boot.itb' not found in input path
>>>
>>> Fix this by separating binman FIT image in rockchip-binman.dtsi
>>>
>>
>> My understanding is that this is a work-around for something that should
>> be implemented in binman instead (e.g. dependency between images). If
>> i'm not mistaken, what you're suggesting is to not build
>> u-boot-rockchip.bin for some platforms? IIRC the plan for this binary
>> was that it would apply to all Rockchip platforms, and this patch makes
>> this "promise" go away.
> 
> Not really, no functionality is changed. It is just that we cannot
> create the final binman image for optee. It is not possible to
> implement in binman alone however if you want to add optee binman
> prior to the final binman can be solvable but it makes unnecessary
> ifdefs and maintaining many binman node definitions in one file seems
> confusing and difficult to maintain.
> 

The project does not want us to use a separate script for building the 
SPL fit image, c.f. the message printed when you build 
(https://source.denx.de/u-boot/u-boot/-/blob/master/Makefile#L1134-L1140) 
so we'll need to migrate to binman eventually.

Patches or suggestions on how to make the binman nodes easier to 
maintain welcome obviously. That's a different topic though.

>>
>>> rockchip-u-boot.dtsi: binman node
>>> rockchip-binman.dtsi: binman FIT image node
>>>
>>> The inclusion of rockchip-binman.dtsi is always to be last in
>>> included files as it has a FIT image node for final image creation.
>>>
>>
>> You are not respecting this in your patch. Please update or remove this
>> section if not required. (I assume you have this limitation because you
>> use a binman phandle, meaning the node needs to be defined before).
>>
>> Also, rockchip-u-boot.dtsi content is now literally:
>> / {
>>          binman: binman {
>>                  multiple-images;
>>          };
>> };
>>
>> which is pretty much useless.
>>
>> Since you want to work around your build issue, why just not include
>> rockchip-u-boot.dtsi instead of moving part of it to another file
>> without any added benefit (at least at first glance, I may be missing
>> some context).
>>
>> BTW, we were discussing some months ago on moving away from
>> make_fit_atf.py to binman for all Rockchip platforms, c.f. the long
>> discussion here:
>> https://urldefense.com/v3/__https://lore.kernel.org/u-boot/20220725172953.GD2029@begut/__;!!OOPJP91ZZw!loeWJQdnvs4xp1KOPE_UekBxO1MVtI8zdMU2brPPR5vPO312JHwp5kdeK2xAzXnMrepRjers3vG5dmMKdVNqzWA2G5WTCZE$  So maybe we
>> should just do this and that might fix the problem you're trying to
>> work-around?
>>
>> In any case, can you provide a bit more context on the failing platform(s)?
> 
> As I explained above, the functionality remains unchanged. Even if you
> build atf via binam dts files the final binman node has to be in the
> order of last since input files like bl31 and tee.bin have depended.

Yes, that's something we discussed on the linked topic. Binman would 
need to gain the ability to express dependencies between nodes. 
Otherwise, one could also force binman to build images sequentially in 
which case (AFAIK) the images are created top to bottom in the binman 
node. It makes the image creation slower but you should get what you want.

AFAIK, binman is what we're supposed to use to create U-Boot binaries 
and binman uses FDT for how to generate them. If there's a better way to 
configure the FDT without ifdef, feel free to suggest something.

> Adding all the binman image creations and the final binman image
> creation in one file make it difficult to read and maintain and
> unnecessary ifdef.
> 

We'll eventually have to make this migration anyways.

Back to the patch.

Applying your patch, rockchip-u-boot.dtsi only contains:
/ {
           binman: binman {
                   multiple-images;
           };
};
This makes very little sense since it is useless and meaningless on its own.

You would need to move this node to the newly added rockchip-binman.dtsi 
which would make this patch just about a file rename. All of this 
because of a build issue for one platform/SoC (as per my understanding). 
If you don't want to work on improving binman to support your use case 
right now, just don't include rockchip-u-boot.dtsi for your platform 
until what you want is supported?

Cheers,
Quentin