On Fri, Oct 2, 2015 at 3:37 PM, David Daney <ddaney.cavm@xxxxxxxxx> wrote: > From: David Daney <david.daney@xxxxxxxxxx> > > PCI Enhanced Allocation is a new method of allocating MMIO & IO > resources for PCI devices & bridges. It can be used instead > of the traditional PCI method of using BARs. > > EA entries are hardware-initialized to a fixed address. > Unlike BARs, regions described by EA are cannot be moved. > Because of this, only devices which are permanently connected to > the PCI bus can use EA. A removable PCI card must not use EA. > > The Enhanced Allocation ECN is publicly available here: > https://www.pcisig.com/specifications/conventional/ECN_Enhanced_Allocation_23_Oct_2014_Final.pdf Looks like the EA will support more than just fixed address later. "Enhanced Allocation is an optional Conventional PCI Capability that may be implemented by Functions to indicate fixed (non reprogrammable) I/O and memory ranges assigned to the Function, as well as supporting new resource “type” definitions and future extensibility to also support reprogrammable allocations." so I would prefer to think more to make frame configurable to leave space for that. Bjorn, I wonder if we need to revive the add-on resource support patchset that i suggested couple years ago, so we can extend it to support EA features. URL: https://lkml.org/lkml/2012/3/19/86 Thanks Yinghai -- 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
