This patch changes Quark SE power drivers to support multicore scenarios
e.g. both LMT and ARC core are enabled and manage power.
Handling LPS states in multicore scenarios are dead simple because LPS
states are core-specific states. It means that putting the LMT core in
LPS doesn't affect the ARC core, and vice-versa. DEEP_SLEEP state, on
the other hand, affects both cores since it turns power off from the SoC
and both cores are shutdown. It means that if LMT puts the system in
DEEP_SLEEP, ARC core is shutdown even if it is busy handling some task.
In order to support the multicore scenario, this patch introduces the
SYS_POWER_STATE_DEEP_SLEEP_2 state to both ARC and x86 power drivers.
On ARC, this state works as following:
1) Save ARC execution context;
2) Raise a flag to inform the x86 core that ARC is ready to enter in
DEEP_SLEEP;
3) Enter in the lowest core-specific power state, which in this case is
LPSS.
On x86, DEEP_SLEEP_2 is very similar to DEEP_SLEEP. The difference relies
in the post_ops() which calls _arc_init() in order to start ARC core so
it can restore its context.
This patch also adds the test/power/multicore/ directory which provides
sample application to x86 and ARC cores in order to easily verify the
multicore support. In test/power/multicore/README.rst you can find more
details regarding the applications.
Jira: ZEP-1103
Change-Id: Ie28ba6d193ea0e58fca69d38f8d3c38ca259a9ef
Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Andre Guedes