Quick Kernel Resume

[zephyrbot]

Reported by Robert Beatty:

As a user of Zephyr I need to be able to re-start the RTOS quickly from a reset (power gated exit).

Example Flow:
CPU is resumed after being powered off, Zephyr goes through a quick-resume path without needing to go through a full init.

(Imported from Jira ZEP-1834)

[zephyrbot]

by Anas Nashif:

this is rather a power management story, should be tracked under some other epic

[zephyrbot]

by Robert Beatty:

Anas Nashif , functionality is already in Zephyr, needs to be enabled per board.

[ramakrishnapallala]

From OS side this supported, however, to enable this on a specific device, the platform/board should support saving and restoring of the RAM contents b/w deep sleep and resume states.

Closing this issue.