Re: [PATCH 04/15] soc: octeontx2: Add mailbox support infra

From: Arnd Bergmann
Date: Tue Aug 28 2018 - 08:52:56 EST


On Tue, Aug 28, 2018 at 2:48 PM Sunil Kovvuri <sunil.kovvuri@xxxxxxxxx> wrote:
>
> On Tue, Aug 28, 2018 at 5:33 PM Arnd Bergmann <arnd@xxxxxxxx> wrote:
> >
> > On Tue, Aug 28, 2018 at 12:57 PM <sunil.kovvuri@xxxxxxxxx> wrote:
> > >
> > > From: Aleksey Makarov <amakarov@xxxxxxxxxxx>
> > >
> > > This patch adds mailbox support infrastructure APIs.
> > > Each RVU device has a dedicated 64KB mailbox region
> > > shared with it's peer for communication. RVU AF has
> > > a separate mailbox region shared with each of RVU PFs
> > > and a RVU PF has a separate region shared with each of
> > > it's VF.
> > >
> > > These set of APIs are used by this driver (RVU AF) and
> > > other RVU PF/VF drivers eg netdev, crypto e.t.c.
> > >
> > > Signed-off-by: Aleksey Makarov <amakarov@xxxxxxxxxxx>
> > > Signed-off-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
> > > Signed-off-by: Lukasz Bartosik <lbartosik@xxxxxxxxxxx>
> >
> > Why does this driver not use the drivers/mailbox/ infrastructure?
> >
> This is a common administrative software driver which will be handling requests
> from kernel drivers and as well as drivers in userspace applications.
> We had to keep mailbox communication infrastructure same across all usages.

Can you explain more about the usage of userspace applications
and what interface you plan to use into the kernel?

Do you things like AF_XDP and virtual machines, or something else?

Arnd