diff options
| author | Jeenu Viswambharan <jeenu.viswambharan@arm.com> | 2018-01-10 15:00:20 +0000 |
|---|---|---|
| committer | Jeenu Viswambharan <jeenu.viswambharan@arm.com> | 2018-02-06 07:58:55 +0000 |
| commit | 26ea390891154aaa3c0236f3c206342cc5d3fdc0 (patch) | |
| tree | 1626ebb743c860435bf95e97781c4027888b77ee /docs | |
| parent | c8b55b8f8be3f6a388d95a7be9af4bf94e47cf86 (diff) | |
Deprecate one EL3 interrupt routing model with EL3 exception handling
When ARM Trusted Firmware is built with EL3_EXCEPTION_HANDLING=1,
EL3 interrupts (INTR_TYPE_EL3) will always preempt both Non-secure and
secure execution.
The interrupt management framework currently treats EL3 interrupt
routing as valid. For the above reason, this patch makes them invalid
when EL3_EXCEPTION_HANDLING is in effect.
Change-Id: I95bca8f5dc8df8eb0ff6f305cfba098611522a39
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/interrupt-framework-design.rst | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/docs/interrupt-framework-design.rst b/docs/interrupt-framework-design.rst index 940bc24f..d5654870 100644 --- a/docs/interrupt-framework-design.rst +++ b/docs/interrupt-framework-design.rst @@ -151,6 +151,10 @@ EL3 interrupts in Secure-EL1/Secure-EL0 is in control of how its execution is preempted by EL3 interrupt and can handover the interrupt to EL3 for handling. + However, when ``EL3_EXCEPTION_HANDLING`` is ``1``, this routing model is + invalid as EL3 interrupts are unconditionally routed to EL3, and EL3 + interrupts will always preempt Secure EL1/EL0 execution. + #. **CSS=0, TEL3=1**. Interrupt is routed to EL3 when execution is in Secure-EL1/Secure-EL0. This is a valid routing model as secure software in EL3 can handle the interrupt. |