On Tue, 2014-08-05 at 13:04 +0100, Michael S. Tsirkin wrote: > > > > +The driver MAY use other accesses for the device-specific configuration space, > > > > +depending on the device type. > > > > >
> Why are you adding this option? > >
> If there's a 4 byte register it is a pain for devices to support > >
> 1 byte accesses, and we gain nothing from it. > > >
> But 2.3 does not limit the configuration space field size nor alignment, >
> does it? >
> No but there is no need: you look at each specific field, you see what
> the size and alignment is. That's what I'm saying. The driver MAY do 8-bit load of the 8-bit field, if the field is defined as such in the device spec. Otherwise all operations on the configuration space would have to be 32-bit wide and aligned. We don't want this, do we? (or do we? :-)
> Are you supporting transitional devices for MMIO?
> If no you don't care what happens with existing drivers. I don't indeed. Pawel