Hi Peng,
+TF-A folk.
My 0.02$.
What is the problem you are trying to solve? Why do you need to run OP-TEE and EHF together? EHF was originally written to support a S-EL0 SP that is managed directly by TF-A in EL3 (TF-A folk can chime in).
The SP could perform RAS error handling for which it needs the EHF. The EHF triages asynchronous exceptions and hands RAS errors to the SP for further handling.
This is just one use case but there is no Trusted OS in these configurations.
So, it would help to understand the requirement.
cheers,
Achin
________________________________
From: OP-TEE <op-tee-bounces(a)lists.trustedfirmware.org> on behalf of Jens Wiklander via OP-TEE <op-tee(a)lists.trustedfirmware.org>
Sent: 17 March 2021 09:23
To: Peng Fan <peng.fan(a)nxp.com>
Cc: op-tee(a)lists.trustedfirmware.org <op-tee(a)lists.trustedfirmware.org>
Subject: Re: EHF + OPTEE on ARM64
On Wed, Mar 17, 2021 at 9:43 AM Peng Fan <peng.fan(a)nxp.com> wrote:
>
> > Subject: Re: EHF + OPTEE on ARM64
> >
> > On Wed, Mar 17, 2021 at 9:02 AM Peng Fan <peng.fan(a)nxp.com> wrote:
> > >
> > > > Subject: Re: EHF + OPTEE on ARM64
> > > >
> > > > On Wed, Mar 17, 2021 at 8:41 AM Peng Fan <peng.fan(a)nxp.com> wrote:
> > > > >
> > > > > > Subject: Re: EHF + OPTEE on ARM64
> > > > > >
> > > > > > On Tue, Mar 16, 2021 at 11:08 AM Peng Fan <peng.fan(a)nxp.com>
> > wrote:
> > > > > > >
> > > > > > > Hi,
> > > > > > >
> > > > > > > In bl31/ehf.c, there are following two lines, per my
> > > > > > > understanding, when cpu is in secure world, the non-secure
> > > > > > > interrupt as FIQ(GICv3) will be directly catched by EL3, not S-EL1
> > > > > > > /* Route EL3 interrupts when in Secure and Non-secure.
> > */
> > > > > > > set_interrupt_rm_flag(flags, NON_SECURE);
> > > > > > > set_interrupt_rm_flag(flags, SECURE);
> > > > > > >
> > > > > > > So this will conflict with OP-TEE, because OP-TEE needs catch
> > > > > > > NS-interrupt as FIQ in S-EL1 world.
> > > > > >
> > > > > > In the case of GICv3, OP-TEE is configured to receive the
> > > > > > non-secure interrupts as FIQ and secure interrupts as IRQ. See
> > CFG_ARM_GICV3.
> > > > >
> > > > > But EHF needs NS-interrupt FIQ be catched by EL3 if I understand
> > > > > correct, per " set_interrupt_rm_flag(flags, SECURE);"
> > > > >
> > > > > So currently EHF could not work together with OP-TEE, right?
> > > >
> > > > To be honest, I'm not completely sure what EHF does. From OP-TEE
> > > > point of view we expect to receive the non-secure interrupts as a
> > > > way of doing a controlled exit. This allows OP-TEE to resume
> > > > execution with a different core on re-entry. If EL3 takes the
> > > > non-secure interrupts directly it will have to make sure to only re-enter
> > OP-TEE on this core as a return from exception.
> > >
> > > Is this easy to be achieved?
> >
> > I don't know, it depends on what you intend to do with this non-secure
> > interrupt. If it's handled at EL3 and then there's a return from exception back
> > to S-EL1 there's likely no harm done. But if there's a world switch involved
> > there might be trouble, OP-TEE might not be in a suitable state for a world
> > switch.
> >
> > >
> > > Or by using opteed_sel1_interrupt_handler, could we have similar
> > > behavior to allow the other core resume execution?
> >
> > Only OP-TEE itself can make a controlled exit as there's an internal state to
> > maintain. Currently that's signalled with a non-secure interrupt.
>
>
> Per EHF, https://trustedfirmware-a.readthedocs.io/en/latest/components/exception-han…
> On GICv3 systems, when executing in S-EL1, pending Non-secure interrupts of
> sufficient priority are signalled as FIQs, and therefore will be routed to EL3.
> As a result, S-EL1 software cannot expect to handle Non-secure interrupts at S-EL1.
> Essentially, this deprecates the routing mode described as CSS=0, TEL3=0.
>
> In order for S-EL1 software to handle Non-secure interrupts while having EHF enabled,
> the dispatcher must adopt a model where Non-secure interrupts are received at EL3,
> but are then synchronously handled over to S-EL1.
>
> The issue to me here how to synchronously handled over to S-EL1 and not break optee.
I understand. OP-TEE is masking interrupts in some critical sections,
while in such a state OP-TEE cannot handle any asynchronous interrupt.
Temporarily masking interrupts is normally a quick operation so we do
it in quite a few places.
So the crux of the problem is to make sure that OP-TEE is in a state
where it can make a controlled exit. I don't have any good ideas for
this right now.
Cheers,
Jens
Hi,
In bl31/ehf.c, there are following two lines, per my understanding,
when cpu is in secure world, the non-secure interrupt as FIQ(GICv3)
will be directly catched by EL3, not S-EL1
/* Route EL3 interrupts when in Secure and Non-secure. */
set_interrupt_rm_flag(flags, NON_SECURE);
set_interrupt_rm_flag(flags, SECURE);
So this will conflict with OP-TEE, because OP-TEE needs catch
NS-interrupt as FIQ in S-EL1 world.
Am I understand correct?
Any ideas how we could address this to make EHF + OPTEE run
together?
Thanks
Peng.
Hi,
If I am not mistaking, the fiq handler should be opteed_sel1_interrupt_handler which will forward the interrupt to S-EL1.
R,
Jelle
________________________________________
From: OP-TEE <op-tee-bounces(a)lists.trustedfirmware.org> on behalf of Peng Fan via OP-TEE <op-tee(a)lists.trustedfirmware.org>
Sent: Tuesday, March 16, 2021 11:08
To: op-tee(a)lists.trustedfirmware.org; Jens Wiklander; Joakim Bech
Subject: EHF + OPTEE on ARM64
Hi,
In bl31/ehf.c, there are following two lines, per my understanding,
when cpu is in secure world, the non-secure interrupt as FIQ(GICv3)
will be directly catched by EL3, not S-EL1
/* Route EL3 interrupts when in Secure and Non-secure. */
set_interrupt_rm_flag(flags, NON_SECURE);
set_interrupt_rm_flag(flags, SECURE);
So this will conflict with OP-TEE, because OP-TEE needs catch
NS-interrupt as FIQ in S-EL1 world.
Am I understand correct?
Any ideas how we could address this to make EHF + OPTEE run
together?
Thanks
Peng.
the word "the" is repeated in the file core.c
so it has been removed. Likewise the word "of"
is repeated in optee_smc.h and have removed it.
Signed-off-by: Anupama K Patil <anupamakpatil123(a)gmail.com>
---
drivers/tee/optee/core.c | 2 +-
drivers/tee/optee/optee_smc.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index cf4718c6d35d..2ccb091cd643 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -422,7 +422,7 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
/*
* TODO This isn't enough to tell if it's UP system (from kernel
- * point of view) or not, is_smp() returns the the information
+ * point of view) or not, is_smp() returns the information
* needed, but can't be called directly from here.
*/
if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1)
diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
index 80eb763a8a80..49e8e027dc5b 100644
--- a/drivers/tee/optee/optee_smc.h
+++ b/drivers/tee/optee/optee_smc.h
@@ -162,7 +162,7 @@ struct optee_smc_call_get_os_revision_result {
* Have config return register usage:
* a0 OPTEE_SMC_RETURN_OK
* a1 Physical address of start of SHM
- * a2 Size of of SHM
+ * a2 Size of SHM
* a3 Cache settings of memory, as defined by the
* OPTEE_SMC_SHM_* values above
* a4-7 Preserved
--
2.25.1
Hi Raghu,
On Wed, Mar 3, 2021 at 8:38 AM Yejerla, VeeraraghavuluX via OP-TEE
<op-tee(a)lists.trustedfirmware.org> wrote:
>
> Dear Sir,
>
> I would like to know that, if I want submit any patch for optee opensource features, could please guide me what are the guide line I have to follow it. Below are some information require .
>
>
> 1. What is the maximum patch size shall I submit?
That depends, it might be good to start with something small as a
first contribution.
> 2. What are the code guide line I have to follow it?
https://optee.readthedocs.io/en/latest/general/coding_standards.html
> 3. What are mail chain I have to include for patch review purpose?
> 4. Is there any open source link for post quarry ?
See https://optee.readthedocs.io/en/latest/general/contribute.html
Cheers,
Jens
Hi,
On Fri, Feb 26, 2021 at 9:50 AM Jérôme Forissier via OP-TEE
<op-tee(a)lists.trustedfirmware.org> wrote:
>
> Hi,
>
> On Thu, Feb 25, 2021 at 9:41 AM Joakim Bech via OP-TEE <
> op-tee(a)lists.trustedfirmware.org> wrote:
>
> > Hi Jorge,
> >
> > On Wed, 24 Feb 2021 at 18:14, Jorge Ramirez <jorge(a)foundries.io> wrote:
> >
> > > Sorry Joakim.
> > > I guess it is too late now but It would have been good to talk about the
> > > TEE strategy/direction with RNG.
> > > 1) how often do we seed the PRNG.
> > > 2) should we always use PRNG and only use HWRNG to seed if with a certain
> > > cadence.
> > > 3) how do we measure the quality of an RNG in OPTEE (how do we guarantee
> > > no regressions)
> > > this would be really an open discussion more than anything else (unless
> > > there is a matematician amongst us)
> > >
> > Yes, good suggestions. I'll add it to the next meeting (March 25:th).
> >
>
> And now that I think of it... there is this big OCALL contribution that has
> been mostly stalled for months...
> https://github.com/OP-TEE/optee_os/pull/3673
> We should discuss what to do with it.
Yes, the kernel part is the hard part here.
Cheers,
Jens
Dear Sir,
I would like to know that, if I want submit any patch for optee opensource features, could please guide me what are the guide line I have to follow it. Below are some information require .
1. What is the maximum patch size shall I submit?
2. What are the code guide line I have to follow it?
3. What are mail chain I have to include for patch review purpose?
4. Is there any open source link for post quarry ?
Regards,
Raghu
Hi,
On Thu, Feb 25, 2021 at 9:41 AM Joakim Bech via OP-TEE <
op-tee(a)lists.trustedfirmware.org> wrote:
> Hi Jorge,
>
> On Wed, 24 Feb 2021 at 18:14, Jorge Ramirez <jorge(a)foundries.io> wrote:
>
> > Sorry Joakim.
> > I guess it is too late now but It would have been good to talk about the
> > TEE strategy/direction with RNG.
> > 1) how often do we seed the PRNG.
> > 2) should we always use PRNG and only use HWRNG to seed if with a certain
> > cadence.
> > 3) how do we measure the quality of an RNG in OPTEE (how do we guarantee
> > no regressions)
> > this would be really an open discussion more than anything else (unless
> > there is a matematician amongst us)
> >
> Yes, good suggestions. I'll add it to the next meeting (March 25:th).
>
And now that I think of it... there is this big OCALL contribution that has
been mostly stalled for months...
https://github.com/OP-TEE/optee_os/pull/3673
We should discuss what to do with it.
Regards,
--
Jerome
Sorry Joakim.
I guess it is too late now but It would have been good to talk about the
TEE strategy/direction with RNG.
1) how often do we seed the PRNG.
2) should we always use PRNG and only use HWRNG to seed if with a certain
cadence.
3) how do we measure the quality of an RNG in OPTEE (how do we guarantee no
regressions)
this would be really an open discussion more than anything else (unless
there is a matematician amongst us)
On Wed, Feb 24, 2021 at 9:18 AM Joakim Bech via OP-TEE <
op-tee(a)lists.trustedfirmware.org> wrote:
> Hi,
>
> Haven't received any suggestions for topics to discuss, so no agenda. No
> agenda means no meeting and therefore I'm cancelling the LOC meeting that
> was scheduled for tomorrow.
>
> Regards,
> Joakim
>
>
> On Wed, 17 Feb 2021 at 15:47, Joakim Bech <joakim.bech(a)linaro.org> wrote:
>
> > Hi,
> >
> > LOC monthly meeting is planned to take place on Thursday February 25th @
> > 16.00 (UTC+1).
> >
> > We're looking for topics to discuss in general. Eventually we'll have a
> > presentation from Achin Gupta from Arm talking about the FF-A spec.
> >
> > Meeting details:
> > ---------------
> > Date/time: Thursday Feb 25th(a)16.00 (UTC+1)
> > https://everytimezone.com/s/c4e5d6a3
> > Connection details: https://www.trustedfirmware.org/meetings/
> > Meeting notes: http://bit.ly/loc-notes
> > Project page: https://www.linaro.org/projects/#LOC
> >
> > Regards,
> > Joakim on behalf of the Linaro OP-TEE team
> >
>