Messages in this thread |  | | Date | Thu, 23 Oct 2014 00:20:21 +0100 | From | Russell King - ARM Linux <> | Subject | Re: [PATCH] RFC: add function for localbus address |
| |
On Wed, Oct 22, 2014 at 04:01:26PM -0700, Stephen Boyd wrote: > Where did this end up? When we talked at Connect I think we settled on > exploring a driver core specific API like dev_get_localbus_address() > that calls of_get_localbus_address() for devices with an of_node and in > the future it could call something like acpi_get_localbus_address() when > there's an acpi_node. I believe the biggest concern is that we're making > an API that is OF or platform bus specific when it doesn't need to be. > Making a driver core specific API avoids this problem by making it bus > agnostic.
Given how little information there is in the original patch as to exactly what problem this is addressing, I could be getting the wrong end of the stick here.
Is this about trying to have a way to obtain the bus local addresses associated with CPU-view resources?
If so, how about looking towards PCI, which has had this problem for the last 15+ years, where PCI bus addresses are not necessarily the same as CPU physical addresses?
There, we don't end up with multiple addresses specified in resources. We instead have a way to translate between resources and bus-local addresses, which IMHO is far nicer and less error-prone than having to specify the same information twice, once with an offset and once without.
-- FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up according to speedtest.net.
|  |