Device trees

[Rafal Jaworowski]

M. Warner Losh wrote:
> In message: <106CEF8A-EA8A-48BC-BAF7-B9C112F58A92 at mac.com>
>             Marcel Moolenaar <xcllnt at mac.com> writes:
> : No, it doesn't.
> 
> Is there any reason it doesn't?  Having looked at the dtc stuff, it
> seems to have all the requirements of device enumeration that we
> talked about at BSDcan...

At the time FreeBSD/MPC85xx was developed the flattened device tree concept
was only getting momentum on Linux, so it was very much fluctuating. But the
main reason was it's quite a bit of work to put everything together and it
wasn't a critical item for the port.

FDT is more or less what we discussed in May, and I think it was mentioned as
one of the possible ways to go. Please note however the FDT infrastructure is
quite heavy and getting it right needs to account for the non-code
dependencies and elements too:

- adopting external (GPL) tools, or providing our own
- working out DTS layouts, OF bindings definitions and conventions (and their
further maintenance) so that they can be used on architectures other that
PowerPC (as having a modern device resources representation accross different
architectures in FreeBSD was very important aspect of our discussions)

Rafal