On Thu, Mar 07, 2013 at 09:08:32AM +0100, Thierry Reding wrote: > Actually I do use device_type = "pciex" for the pci@1,0 and pci@2,0 > nodes which was suggested back when I first posted this series. Yet the > address translation still works properly. And it should since they are > translated to the parent bus which is used to access the configuration > space window for each root port. Right - pciex != pci - as you note: > Looking at the code it looks indeed like the OF core only matches on > "pci" (and "vci"), but not "pciex". Perhaps I should change both nodes > to device_type = "pci" and see what the results are. The string 'pci' engages the special behavior, pciex isn't a valid keyword. This is why I keep saying these bindings need to use 'device_type = "pci"' :) > > Both have various problems, but I think I prefer the first one as it > > doesn't conflate the contoller registers and host apertures in a > > single ranges.. > > I think a better alternative would be (and this matches what Thomas has > said elsewhere) to use something like the first alternative but move the > regs property into the pcie@0,X nodes. That would save us from having to > index a property in the parent. At least from a DT point of view I find > that to be a more consistent representation. You are thinking a new property 'host-controller-regs' or the like? > However that would probably not work out-of-the-box with the current OF > core because of_address_to_resource() won't know how to find the new > property. The assigned-addresses alternative seems to be the only one > that would work on the current OF core and achieve proper address > translation. But it doesn't seem like a good solution either since it > repurposes the meaning of the property and therefore isn't any better > than encoding the same information in the reg property. Except that reg is specifically not supposed to be handling CPU bus addresses and assigned-addresses is. Adding a hidden non-standard BAR to model the hidden non-standard memory region associated with the bridge is a stretch, but it is not a very big stretch... In any event, regs should not be used, and something needs to be decided! Regards, 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
