On Mon, Jan 28, 2013 at 11:30:48PM +0100, Thomas Petazzoni wrote: > Dear Jason Gunthorpe, > > On Mon, 28 Jan 2013 15:23:48 -0700, Jason Gunthorpe wrote: > > > I'm refering to your earlier question about what PCI IDs to use for > > the SW emulated devices. If there is no need for the host bridge then > > you only need 1 PCI ID (for the root port bridge) and you can probably > > fairly safely re-use the one in the Marvell config space of the HW. > > Ah, ok, I see. But isn't a host bridge needed to bind all the > PCI-to-PCI bridges under a single bus, in order to get the global > resource assignment I was referring to? The PCI-E spec requires it, but AFAIK it doesn't actually *do* anything on Linux, and Linux doesn't require it. I thought Thierry did this experiment and decided it wasn't necessary: > The reason is that with the latest bindings the matching of root > ports to device tree nodes works as-is and nothing else indicates > that the emulated host bridge is actually required to make any of > this work. So in order not to introduce unneeded code I've left it > out for now. If somebody decides that we actually need this host > bridge (for standards compliance or whatnot) it could easily be > added back. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
