Re: integrating dtc into the sim/ tree

[Joel Sherrill <joel.sherrill@oarcorp.com>]

On 8/20/2014 11:06 AM, Joel Brobecker wrote:
>> moxie is the only one that hard requires dtc (it might be limited to
>> maintainer mode).  but the larger point is to delete a large body of
>> custom code that the sim has today for parsing its device tree like
>> data format and convert over to the standard format that the rest of
>> the world is using now.  and longer term, make it so we can share dtc
>> files between linux/u-boot/qemu such that you can feed a fdt to the
>> sim and it'll automatically bring up hardware in the same way as the
>> kernel would have found it.
>>
>> atm, you have to basically write two different device trees with
>> different syntax and names, then feed one to the sim and the other to
>> the kernel.  and hope they don't get out of sync :).
>>
>> there's basically no chance of people rewriting the existing sim code
>> so that it gains all the same functionality as the public dtc, and
>> then keeping it in sync.  i'd rather just gut it and be done, and get
>> the dtc updates for free.
> My 2 cents: This sounds interesting, but on the other hand, I have
> this feeling that requiring dtc might be a big ask. I'm not sure
> how portable the dtc project is, and how easy it is to get it
> installed. I went to the "Device Tree Compiler" page you referenced,
> and it doesn't give at all the impression of being a mature and
> widespread project... For instance, I was looking for the documentation
> in order to check for things like installation, OS support,
> requirements, etc. I ended up looking inside the source tree itself,
> and found Documentation/manual.txt and README, but none of them answered
> any of these questions. I am also wondering about releases and such,
> but couldn't really find much about it.
>
> I hope this explains why I would personally feel a little more
> comfortable if that dependency remained optional.
>
> Now, if the project was really super easy to install and completely
> portable (think Linux & Windows, of course, but also Darwin,
> Solaris...), I would consider making it mandatory.
>
I would have been happy if the generated files were in the tree and
only maintainer mode would result in the dependencies being checked.

This has precedence for other tools.

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel.sherrill@OARcorp.com        On-Line Applications Research
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