Re: [PATCH 0/2] OP-TEE FF-A notifications

[Jens Wiklander]

Hi Sumit,

On Mon, Oct 30, 2023 at 11:32:47AM +0530, Sumit Garg wrote:
> Hi Jens,
> 
> On Thu, 26 Oct 2023 at 13:34, Jens Wiklander <jens.wiklander@xxxxxxxxxx> wrote:
> >
> > Hi all,
> >
> > This patchset adds support for using FF-A notifications as a delivery
> > mechanism of asynchronous notifications from OP-TEE running in the secure
> > world. Support for asynchronous notifications via the SMC ABI was added in
> > [1], here we add the counterpart needed when using the the FF-A ABI.
> >
> > Support for FF-A notifications is added with [2] and this patch set is based
> > on Sudeeps tree at [3].
> 
> It's good to see FF-A notifications support coming through. The good
> aspect here is that FF-A uses a common secure world SGI for
> notifications and doesn't have to deal with platform specific reserved
> SPI for notifications.
> 
> From OP-TEE point of view I think most of the secure SGI donation base
> would be common, so can we switch the SMC ABI to use this donated
> secure world SGI for notifications too?

The SMC ABI driver picks up the interrupt used for notification from
device-tree, so there's a chance that it just works if a donated SGI is
supplied instead. We'll need some changes in the secure world side of
OP-TEE, but they wouldn't affect the ABI.

Cheers,
Jens

> 
> -Sumit
> 
> >
> > [1] https://lore.kernel.org/lkml/20211103090255.998070-1-jens.wiklander@xxxxxxxxxx/
> > [2] https://lore.kernel.org/linux-arm-kernel/20231005-ffa_v1-1_notif-v4-0-cddd3237809c@xxxxxxx/
> > [3] https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git/tag/?h=ffa-updates-6.7
> >     commit bcefd1bf63b1 ("firmware: arm_ffa: Upgrade the driver version to v1.1")
> >
> > Thanks,
> > Jens
> >
> > Jens Wiklander (2):
> >   optee: provide optee_do_bottom_half() as a common function
> >   optee: ffa_abi: add asynchronous notifications
> >
> >  drivers/tee/optee/call.c          | 31 ++++++++++-
> >  drivers/tee/optee/ffa_abi.c       | 91 ++++++++++++++++++++++++++++++-
> >  drivers/tee/optee/optee_ffa.h     | 28 ++++++++--
> >  drivers/tee/optee/optee_private.h |  9 ++-
> >  drivers/tee/optee/smc_abi.c       | 36 ++----------
> >  5 files changed, 153 insertions(+), 42 deletions(-)
> >
> >
> > base-commit: bcefd1bf63b1ec9bb08067021cf47f0fad96f395
> > --
> > 2.34.1
> >