[PATCH v1 1/2] drivers: firmware: introduce Meson Secure Monitor driver

[Simon Glass]

Hi Alexey,

On Fri, 7 Jul 2023 at 09:43, Alexey Romanov <AVRomanov at sberdevices.ru> wrote:
>
> Hello, Simon!
>
> On Thu, Jul 06, 2023 at 09:58:02AM -0600, Simon Glass wrote:
> > Hi Alexey,
> >
> > On Thu, 6 Jul 2023 at 14:16, Alexey Romanov <avromanov at sberdevices.ru> wrote:
> > >
> > > At the moment, only smc API is a set of functions in
> > > arch/arm/mach-meson/sm.c. This approach is hard to configure
> > > and also doesni't contain any generic API for calling smc.
> > >
> > > This patch add Meson SM driver with generic API (struct meson_sm_ops):
> > >
> > > - sm_call()
> > > - sm_call_write()
> > > - sm_call_read()
> > >
> > > A typical driver usage example is shown here:
> > >
> > > 1. uclass_get_device_by_driver(UCLASS_FIRMWARE, "secure-monitor", &dev);
> > > 2. handle = meson_sm_get_handle(dev);
> > > 3. handle->ops.sm_call(dev, cmd, ...);
> > >
> > > Signed-off-by: Alexey Romanov <avromanov at sberdevices.ru>
> > > ---
> > >  arch/arm/mach-meson/Kconfig       |   1 +
> > >  drivers/firmware/Kconfig          |  10 ++
> > >  drivers/firmware/Makefile         |   1 +
> > >  drivers/firmware/meson/Kconfig    |   6 +
> > >  drivers/firmware/meson/Makefile   |   3 +
> > >  drivers/firmware/meson/meson_sm.c | 217 ++++++++++++++++++++++++++++++
> > >  include/meson/sm_handle.h         |  38 ++++++
> > >  7 files changed, 276 insertions(+)
> > >  create mode 100644 drivers/firmware/meson/Kconfig
> > >  create mode 100644 drivers/firmware/meson/Makefile
> > >  create mode 100644 drivers/firmware/meson/meson_sm.c
> > >  create mode 100644 include/meson/sm_handle.h
> >
> > Please can you use the remoteproc uclass for this and add a proper driver?
> >
>
> I don't see it architecturally well. Can you explain please?
>
> This driver is just ARM SMC fw interface. There seems to be nothing to
> do here for remoteproc uclass.

Well you seem to be implementing a remote CPU interface, which is what
remoteproc is for. How does Linux do this?

Also there is a pending series on FFA - is that related? It uses smc
from what I can tell.

Regards,
Simon