Clear doorbells which have been posted to the opposite core. This register is intended for debugging and initialisation purposes.
Writing 1 to a bit in DOORBELL_OUT_CLR clears the corresponding bit in DOORBELL_IN on the opposite core. Clearing all bits will cause that core’s doorbell interrupt to deassert. Since the usual order of events is for software to send events using DOORBELL_OUT_SET, and acknowledge incoming events by writing to DOORBELL_IN_CLR, this register should be used with caution to avoid race conditions.
Reading returns the status of the doorbells currently asserted on the other core, i.e. is equivalent to that core reading its own DOORBELL_IN status.
| DOORBELL_OUT_CLR |