Master-aware devices and sideband ID data

On Thu, Jun 04, 2015 at 11:19:30PM +0100, Chalamarla, Tirumalesh wrote:

quoted

On Jun 1, 2015, at 3:22 AM, Mark Rutland [off-list ref] wrote:
It's possible to specify that the paths exist. I expect that software
would select which to use at runtime.

My worry is how to define any priorities/preferences between masters. 
in general the proposal looks reasonable.

I agree that the proposal looks reasonable (in terms of the ability to
describe the sort of topologies that we will face) but I still don't
understand what I need to do in e.g. my IOMMU driver to support this
binding whilst continuing to support the existing iommus binding, which
is relied upon to configure dma-mapping.

Mark: how do you see this co-existing/merging with the current bindings?
I don't think it's practical to throw away what we have and move over to
something totally different all in one go, but there clearly *is* benefit
in your proposal over the existing scheme.

Will