Re: [PATCH v3 09/10] firmware: arm_ffa: Set up 32bit execution mode flag using partiion property

From: Sudeep Holla
Date: Thu Sep 08 2022 - 06:25:57 EST


On Thu, Sep 08, 2022 at 12:08:00PM +0200, Jens Wiklander wrote:
> On Wed, Sep 7, 2022 at 4:53 PM Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
> >
> > FF-A v1.1 adds a flag in the partition properties to indicate if the
> > partition runs in the AArch32 or AArch64 execution state. Use the same
> > to set-up the 32-bit execution flag mode in the ffa_dev automatically
> > and ignore any requests to do the same from the ffa_driver.
> >
> > Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> > ---
> > drivers/firmware/arm_ffa/driver.c | 13 ++++++++++++-
> > include/linux/arm_ffa.h | 2 ++
> > 2 files changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
> > index 42bc22220c69..34e12a2a98fe 100644
> > --- a/drivers/firmware/arm_ffa/driver.c
> > +++ b/drivers/firmware/arm_ffa/driver.c
> > @@ -648,11 +648,19 @@ static int ffa_partition_info_get(const char *uuid_str,
> > return 0;
> > }
> >
> > -static void ffa_mode_32bit_set(struct ffa_device *dev)
> > +static void _ffa_mode_32bit_set(struct ffa_device *dev)
> > {
> > dev->mode_32bit = true;
> > }
> >
> > +static void ffa_mode_32bit_set(struct ffa_device *dev)
> > +{
> > + if (drv_info->version > FFA_VERSION_1_0)
> > + return;
> > +
> > + _ffa_mode_32bit_set(dev);
> > +}
> > +
> > static int ffa_sync_send_receive(struct ffa_device *dev,
> > struct ffa_send_direct_data *data)
> > {
> > @@ -744,6 +752,9 @@ static void ffa_setup_partitions(void)
> > __func__, tpbuf->id);
> > continue;
> > }
> > +
> > + if (!(tpbuf->properties & FFA_PARTITION_AARCH64_EXEC))
> > + _ffa_mode_32bit_set(ffa_dev);
>
> For FF-A 1.0 it looks like we change the dev->mode_32bit default value
> from false to true. Or am I missing something?
>

You are right, was trying to avoid additional check on version but we
need that to keep the behaviour unchanged. I will add the check. Thanks
again for spotting this.

--
Regards,
Sudeep