[PATCH 2/3] imx8m: Automatically add the optee firmware node to the FDT

[Jens Wiklander]

Hi,

On Mon, May 16, 2022 at 12:00 PM Michael Nazzareno Trimarchi
<michael at amarulasolutions.com> wrote:
>
> Hi Alban
>
> On Mon, May 16, 2022 at 10:23 AM Alban Bedel <alban.bedel at aerq.com> wrote:
> >
> > If optee is running add the firmware node to the FDT to allow the
> > kernel to use a more generic device tree.
> >
> > Signed-off-by: Alban Bedel <alban.bedel at aerq.com>
> > ---
> >  arch/arm/mach-imx/imx8m/soc.c | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> >
> > diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c
> > index 8e23e6da326f..2a78cb6a0952 100644
> > --- a/arch/arm/mach-imx/imx8m/soc.c
> > +++ b/arch/arm/mach-imx/imx8m/soc.c
> > @@ -30,6 +30,7 @@
> >  #include <fsl_wdog.h>
> >  #include <imx_sip.h>
> >  #include <linux/bitops.h>
> > +#include <tee/optee.h>
> >
> >  DECLARE_GLOBAL_DATA_PTR;
> >
> > @@ -1347,6 +1348,14 @@ usb_modify_speed:
> >  #endif
> >
> >         cleanup_nodes_for_efi(blob);
> > +
> > +       if (rom_pointer[1]) {
> > +               int err = optee_add_firmware_node(blob, "linaro,optee-tz",
> > +                                                 "smc");
> > +               if (err)
> > +                       return err;
> > +       }
> > +
> >         return 0;
> >  }
> >  #endif
> > --
>
> Adding the node is not sufficient. I think that we need reserved
> memory node on top of it. The nice scenario will be
> only to define the size of such area and use always the last part of
> the memory to reserve it. Do you know if we have some api
> to pass information to the atf and optee?

We have an ABI in OP-TEE for this, OPTEE_SMC_GET_SHM_CONFIG. This
function wasn't intended for this, but I can't see that that should be
a problem.

Cheers,
Jens

>
> Michael
> > 2.34.1
>
>
>
> --
> Michael Nazzareno Trimarchi
> Co-Founder & Chief Executive Officer
> M. +39 347 913 2170
> michael at amarulasolutions.com
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