Re: building Yocto for Pandaboard

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Thu, 2012-02-09 at 14:54 +0100, Koen Kooi wrote:
> Op 9 feb. 2012, om 14:11 heeft jfabernathy het volgende geschreven:
> > On 02/09/2012 08:01 AM, Maupin, Chase wrote:
> >>> Wow!  Sorry I jumped into a mailing list I obviously don't
> >>> understand or belong in.  I apologize if I offended.  I did read
> >>> the README, but it didn't make a bit of sense to me because it
> >>> talked about angstrom, which I don't know anything about and
> >>> wondered what that had to do with yocto.  My current Yocto
> >>> knowledge is based on the meta-intel layer, which doesn't mention
> >>> angstrom.  It sounds like the hint/trick that Gary mentioned will
> >>> make bitbake build with just yocto, which is what I want.  My goal
> >>> is more of a proof of concept.  I'd like to prove if you could take
> >>> the same image recipe and move it from Pandaboard to Atom and vice
> >>> versa.  That way a developer could pick the hardware platform based
> >>> on the performance, features, and cost.  The software effort should
> >>> be minimal to move if the Yocto concept works as advertised.
> >> Jim, you are welcome here.  As was mentioned before there have been
> a lot of discussions about this layer.  One of the goals for the
> meta-ti layer will be to work with just oe-core and yocto and not
> require meta-angstrom.  We are moving that direction and the use case
> you are trying and your experiences with it are important.  Thanks for
> taking the time to give this a shot.
> >> 
> > Thanks, glad the proof of concept falls into the groups thinking as
> well.  I will monitor for progress on the use of just the Yocto Linux
> for this POC.
>
> Yocto or Poky? Because if you want yocto, angstrom very much *is*
> yocto. If you want Poky, that's something different.

I think there are a few things need to get cleared up here as this is
likely confusing for people.

The Yocto Project is the overall project which is working on improving
embedded Linux for people in whatever areas those improvements are
needed in. This involves things like eglibc, creating standard formats
for hardware definitions (BSPs) and has also involved some work on build
system which are derived from OpenEmbedded.

The Yocto Project uses Poky as its reference build system which is a
combination of Bitbake, OE-Core, a load of documentation and a very
small shim called meta-yocto. Its purpose is to provide a known good
base system people can build on top of by adding layers.

Angstrom is similar to Poky in that its a mix of components allowing
people to build things. It includes Bitbake and OE-Core and some other
pieces. It has an equivalent to meta-yocto with different functionality.
I'll let Koen as one of its maintainers describe what its purpose is.
One difference is that is has a specific set of hardware targets and
provides prebuilt package feeds which Poky does not (nor does the Yocto
Project).

meta-ti is intended as a hardware support layer for various TI products.

The trouble is that some of these components have been around for a
while and it hasn't always been possible to neatly layer things. In
particular, meta-ti historically has a dependency on Angstrom.

Work is underway to remove that dependency so meta-ti can operate freely
with both Poky and Angstrom, or just with OE-Core and Bitbake as
separate pieces. There is no architectural problem with this and it is
the intention of everyone involved. There is the question of sorting
some of the mechanics and making the change whilst not causing problems
for existing users. I'm really happy to see progress on this!

So in answer to Jim's question, you will be able to use meta-ti with
Poky directly but right now, there are some details being worked through
and it doesn't quite work. Perhaps we could mention that in the meta-ti
README so people can see what the plan is as well as the current
situation?

Cheers,

Richard