Re: [PATCH 2/2] firmware: psci: support SMCCC v1.2 for SMCCC conduit

[Etienne Carriere <etienne.carriere@linaro.org>]

On Thu, 14 May 2020 at 16:24, Sudeep Holla <sudeep.holla@arm.com> wrote:
>
> On Thu, May 14, 2020 at 10:21:09AM +0200, Etienne Carriere wrote:
> > Update PSCI driver to support SMCCC v1.2 reported by secure firmware
> > and indirectly make SMCCC conduit properly set when so. TF-A release
> > v2.3 implements and reports SMCCC v1.2 since commit [1].
> >
> > Link: [1] https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=e34cc0cedca6e229847c232fe58d37fad2610ce9
> > Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
> > ---
> >  drivers/firmware/psci/psci.c | 14 ++++++++++----
> >  include/linux/psci.h         |  1 +
> >  2 files changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
> > index 2937d44b5df4..80cf73bea4b0 100644
> > --- a/drivers/firmware/psci/psci.c
> > +++ b/drivers/firmware/psci/psci.c
> > @@ -409,11 +409,17 @@ static void __init psci_init_smccc(void)
> >       feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
> >
> >       if (feature != PSCI_RET_NOT_SUPPORTED) {
> > -             u32 ret;
> > -             ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
> > -             if (ret == ARM_SMCCC_VERSION_1_1) {
> > +             ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
> > +
> > +             switch (ver) {
> > +             case ARM_SMCCC_VERSION_1_1:
> >                       psci_ops.smccc_version = SMCCC_VERSION_1_1;
> > -                     ver = ret;
> > +                     break;
> > +             case ARM_SMCCC_VERSION_1_2:
> > +                     psci_ops.smccc_version = SMCCC_VERSION_1_2;
> > +                     break;
> > +             default:
> > +                     break;
> >               }
> >       }
> >
> > diff --git a/include/linux/psci.h b/include/linux/psci.h
> > index a67712b73b6c..c7d99b7f34ed 100644
> > --- a/include/linux/psci.h
> > +++ b/include/linux/psci.h
> > @@ -24,6 +24,7 @@ bool psci_has_osi_support(void);
> >  enum smccc_version {
> >       SMCCC_VERSION_1_0,
> >       SMCCC_VERSION_1_1,
> > +     SMCCC_VERSION_1_2,
>
> I took approach to kill this completely [1] instead of having to keep
> expanding it for ever.

Yes, I've been pointed to [1]. Discard this change. Sorry for the
(little) noise.

Etienne

> --
> Regards,
> Sudeep
>
> [1] https://lore.kernel.org/linux-arm-kernel/20200506164411.3284-5-sudeep.holla@arm.com/