Dear ARM experts
I run a bare metal on cortex-a53x4 SOC, I want to access system generic timer, but the generic timer is a external secure physical timer. My program is run in non-secure EL1 exception level, so how can I access the
secure generic timer.
Thanks!
You cannot access the secure timer from non-secure EL1 code.
You may implement a EL3 service routine to read the secure physical timer so that it can provide the secure timer value.
You non-secure EL1 code can utilize the SMCCC API call to trap to EL3 to request the secure timer service.
- https://developer.arm.com/architectures/system-architectures/software-standards/smccc