SWRZ110A May 2021 – January 2022 CC2652R7
An Incorrect Value Might Be Written to the General-Purpose (GP) Timers MMRs (Memory Mapped Registers) When Simultaneously Accessing the PKA (Public Key Accelerator) Engine and/or the AES (Advanced Encryption Standard) Engine from a Different Master
Revision B
When writing data to the GP Timer MMRs from one master while simultaneously accessing the PKA/AES modules from another master (read/write), an incorrect value might be captured in the GP Timer MMRs. In some cases, the incorrect value is replaced by the correct one after two clock cycles, but not always. No issue is seen when accessing the modules from the same master.
Avoid accesses to PKA/AES by other masters while writing to the GP Timer MMRs. This can be accomplished by acquiring the relevant semaphores (depending on drivers/stacks) before writing to the GP Timer.
Note that the BLE stack executes crypto operations from ISR context. Other software must release the semaphores from a higher-priority ISR to avoid deadlocks.
Verify the value written to the GP Timer MMR by reading it back in software. Correct the value if necessary.