diff options
| author | Jeenu Viswambharan <jeenu.viswambharan@arm.com> | 2018-01-22 12:29:12 +0000 |
|---|---|---|
| committer | Jeenu Viswambharan <jeenu.viswambharan@arm.com> | 2018-02-27 13:46:33 +0000 |
| commit | af34cd72ca3b716d8a9800c83b1577e3a39cf41b (patch) | |
| tree | 49d896aee91e6dae2edbcacae0afc3b3b983394d /include | |
| parent | 5ff6da948710361dec294f4b5106978501531caf (diff) | |
EHF: Introduce preempted return code parameter to ehf_allow_ns_preemption()
When a Yielding SMC is preempted, it's possible that Non-secure world is
resumed afterwards. In this case, Non-secure execution would find itself
in a state where the SMC has returned. However, the dispatcher might not
get an opportunity to populate the corrected return code for having
been preempted, and therefore the caller of the Yielding SMC cannot
reliably determine whether the SMC had successfully completed or had
been preempted.
To solve this, this patch introduces a new parameter to the
ehf_allow_ns_preemption() API. An SPD, through this parameter, would
provide the expected error code when a Yielding SMC is preempted. EHF
can then populate the specified value in x0 of the Non-secure context so
that the caller of the Yielding SMC correctly identifies the SMC return
as a preemption.
Documentation updates to follow.
Change-Id: Ia9c3f8f03f9d72d81aa235eaae2ee0374b972e1e
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/bl31/ehf.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/bl31/ehf.h b/include/bl31/ehf.h index be8c957c..f963f8d0 100644 --- a/include/bl31/ehf.h +++ b/include/bl31/ehf.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved. + * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ @@ -82,7 +82,7 @@ void ehf_init(void); void ehf_activate_priority(unsigned int priority); void ehf_deactivate_priority(unsigned int priority); void ehf_register_priority_handler(unsigned int pri, ehf_handler_t handler); -void ehf_allow_ns_preemption(void); +void ehf_allow_ns_preemption(uint64_t preempt_ret_code); unsigned int ehf_is_ns_preemption_allowed(void); #endif /* __ASSEMBLY__ */ |