This CL introduces power management driver that improves the efficiency
of ec operation by adjusting the chip’s power consumption to the level
of activity required by the application in npcx series.
The following list summarizes the main properties of the various chip
power states. Please refer the power.c file for more detail.
Main power states in npcx series include:
- Active: Core, RAM and modules operate at the clocks generated by PLL.
- Idle: Enter this state when the Core executes WFI or WFE instruction.
- Sleep: clock is stopped for most of modules but PLL is enabled.
- Deep Sleep: As Sleep mode but PLL is disabled.
- Standby: All power rails are turned off besides standby and battery
power rails.
And this CL implements one power state, PM_STATE_SUSPEND_TO_IDLE, with
two sub-states for Zephyr power management system.
Sub-state 0 - "Deep Sleep" mode with “Instant” wake-up if residency
time is greater or equal to 1 ms
Sub-state 1 - "Deep Sleep" mode with "Standard" wake-up if residency
time is greater or equal to 201 ms
Signed-off-by: Mulin Chao <mlchao@nuvoton.com>