On systems with I225 interfaces it works in interrupt mode(rx), so not only
LSE interrupts are supported.
I could try add  rte_intr_cap_single functionality and recheck it twice(if
several interfaces works in rx_mode=interrupt)
But actually it worked with changes above(CPU utilization close to the
zero, data passes through the interface etc)

On Tue, Jul 4, 2023 at 5:55 PM Stephen Hemminger <stephen@networkplumber.org>
wrote:

> On Tue, 4 Jul 2023 12:45:54 +0200
> Vladimir Ratnikov <vratnikov@netgate.com> wrote:
>
> > Sorry for a long reply, sure.
> >
> > Stephen,
> > am I right that the most concern is about a place where interrupt
> > capabilities check appears for non MSI-X support?
> > What if having dedicated rte_intr_cap_single analog when there's no
> support
> > for MSI-X and just do the same(check capability, allocate interrupt
> vector
> > etc) ?
> >
> >
> > Regards,
> > -Vladimir
>
> With single interrupt, only link state interrupt is possible.
> Does that work with igb_uio?  It should, if not then yes
> rte_intr_cap_single
> or something like that is needed.
>