The power down is initiated by the Cortex-R5F MPCore. As the TCM is placed in retention, the Cortex-R5F MPCore is required to do the following (This Figure).
1.Set the TCM bit in the RAM_RET_CNTRL register.
2.Set the TCM bit in the REQ_PWRDWN_TRIG register while the interrupt is masked for the TCM in the REQ_PWRDWN_INT_MASK register.
3.Set the RPU and TCM bits in the REQ_PWRUP_TRIG register while the interrupt mask bits for those fields are disabled.
4.Set the RPU bit in the REQ_SWRST_TRIG while the interrupt mask bit for it is disabled.
5.Set the alarm.
6.Disable interrupts.
7.Set the SLCR bit to request for a direct RPU power down and execute a WFI instruction.
This procedure causes an interrupt to the PMU to power down the RPU.