Re: RFC qdev path semantics

Paul Brook
2010-06-16T11:45:34Z

> Markus Armbruster wrote:
> > A number of changes to qdev paths have been proposed in various threads.
> > It's becoming harder to keep track of them, so let me sum them up in one
> > place. Please correct me if I misrepresent your ideas.
> >
> > I'm going to describe the current state of things, and the proposed
> > changes (marked with ###).
> >
> >
> > The device tree has the main system bus as root. A child of a bus is a
> > device. A child of a device is a bus.
> >
> > A qdev path consists of qdev path components separated by '/'. It
> > resolves to a node in the device tree, either bus or device.
> >
> > The qdev path "/" resolves to the root, i.e. the main system bus.
>
> Another aspect: A path may start with an arbitrary bus name, not only
> the system bus. Although this is ambiguous, we need to keep it for
> addressing the bus itself due to existing client use. But, IMO, we
> should at least start deprecating this for addressing elements below
> that bus (e.g. "pci.0/e1000").

I think this would be better served by adding explicit aliases/IDs for those
use-cases. i.e. define the global ID "pci.0" to be an alias for
/i440FX-pcihost/pci

Paul