Re: [PATCH V3] firmware: arm_scmi: Make scmi core independent of the transport type

From: Sudeep Holla
Date: Tue Jan 21 2020 - 13:38:27 EST


On Tue, Jan 21, 2020 at 04:11:11PM +0100, Arnd Bergmann wrote:
> On Tue, Jan 21, 2020 at 9:27 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
> >
> > The SCMI specification is fairly independent of the transport protocol,
> > which can be a simple mailbox (already implemented) or anything else.
> > The current Linux implementation however is very much dependent on the
> > mailbox transport layer.
> >
> > This patch makes the SCMI core code (driver.c) independent of the
> > mailbox transport layer and moves all mailbox related code to a new
> > file: mailbox.c.
> >
> > We can now implement more transport protocols to transport SCMI
> > messages.
> >
> > The transport protocols just need to provide struct scmi_transport_ops,
> > with its version of the callbacks to enable exchange of SCMI messages.
> >
> > Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > ---
> > @Sudeep: Can you please help me getting this tested?
> >

Sure(I may need to rebase on top of -next to test on top of what's queued
for v5.6)

> > V2->V3:
> > - Added more ops to the structure to read/write/memcpy data
> > - Payload is moved to mailbox.c and is handled in transport specific way
> > now. This resulted in lots of changes.
>
> This addresses the comments I had about the implementation.
>

Thanks for review and all the suggestions Arnd.

> It's still hard for me to judge whether this is a good abstraction as
> long as there is only one backend in the framework, but I see nothing
> immediately wrong with it either.
>

Peter and Peng(both in cc) is trying out virtio and smc/hvc based transport
respectively. Hopefully they will raise concerns(if any) with the abstraction.

--
Regards,
Sudeep