Device Tree Blob for Beaglebone Black?

[Amar Takhar]

On 2020-02-27 08:45 +0100, Christian Mauderer wrote:
> 
> It's just another problem that I noted sometimes on the mailing list
> with RTEMS and libbsd: Sometimes libbsd doesn't compile with some odd
> error messages like unresolved symbols. Most of the time the problem is
> that libbsd has been updated by the user but RTEMS hasn't. Having
> defined versions in a master repository could help the average user to
> see which version should be used together. On the other hand someone
> would have to keep it up to date and I'm not sure whether all
> maintainers would be happy about another necessary maintainance task.
> Therefore it's not yet a well thought through idea.

The only good way to handle this is to have it all in 1 giant repository we work 
with.  Every other solution is a pain no matter how well thought out it is.  I 
personally lean more on the service side of things that it should be *our* 
problem to maintain this and for users it should just work.

The easiest way to handle this is to have the minimum version required in the 
commit message.  Eg, when pushing to libbsd have:

  Minimum RTEMS: <hash>

After that it's up to the user to ensure to keep up-to-date.  The first thing 
most developers do is check the log.

Regardless of what we choose none of it will work if the user is not updating 
their repository or checking online for changes.  Having it in the commit 
message also helps for build automation.  I've used git tags for this in the 
past but hardly anyone uses or checks those which is too bad.


> If you are a new user and see "for this BSP use the FDT from X" but you
> want to use some other BSP and someone tells you "for that BSP the FDT
> isn't in X but at Y" it maybe isn't really that clear. Therefore - if we
> introduce some handling - I would be in favor of only one location and
> not a mix of two or three. Otherwise the situation is only slightly
> better than now.

Having a section in the documentation to manage this is fine I think.  It's 
either going to say:

  1. The FDT source is in rtems-fdt.git
  2. The FDT source is already in RTEMS you don't need to do anything.
  3. You need to purchase a board and place the files <here>
  4. Covers all: If you want to roll your own place the files <here> -- same 
     place as #3 maybe.

An easier way to make a decision would be to see what we're looking at right 
now.  How many would be in-tree and how many external?


Amar.