Add save/restore support to ARC core

[zephyrbot]

Reported by Julien Delayen:

When restoring from sleep, the x86 core will start the ARC core which will need
to restore its context (registers, program counter).

The ARC shim layer will support sleep and deep sleep and the power
sample will be supporting the ARC.

This does not involve any type of communication between the core and
assumes the x86 is ready to en ter sleep at any time.
The communication will be treated as a separate story.

(Imported from Jira ZEP-1222)

[zephyrbot]

by Qiu Peiyang:

Board= quark_se_c1000_devboard
https://gerrit.zephyrproject.org/r/#/c/6913/(power: Add ARC core suspend and resume support
)
https://gerrit.zephyrproject.org/r/6911(arcv2_irq: Add power management suspend/resume
)
https://gerrit.zephyrproject.org/r/#/c/6912/(arcv2_timer0: Add suspend and resume support
)
https://gerrit.zephyrproject.org/r/#/c/7090/(arc: Define _arc_v2_irq_unit device
)

I cherry-pick the four patches related to PM on ARC core, and then run tests/power/power_states.
The first round of power state switch is ok, but the second round stops after printing "Entering SYS_POWER_STATE_CPU_LPS state", and then the console blocks.

Quark SE: Power Management sample application
Entering SYS_POWER_STATE_CPU_LPS state
Exiting SYS_POWER_STATE_CPU_LPS state
Back to the application
Entering SYS_POWER_STATE_CPU_LPS_1 state
Exiting SYS_POWER_STATE_CPU_LPS_1 state
Back to the application
Entering SYS_POWER_STATE_CPU_LPS_2 state
Exiting SYS_POWER_STATE_CPU_LPS_2 state
Not enough time for PM operations (ticks: 98).
Back to the application
Entering SYS_POWER_STATE_DEEP_SLEEP state
Woke up with RTC (pin:1)
Exiting SYS_POWER_STATE_DEEP_SLEEP state
Back to the application
Entering SYS_POWER_STATE_DEEP_SLEEP_1 state
Woke up with RTC (pin:1)
Exiting SYS_POWER_STATE_DEEP_SLEEP_1 state
Back to the application
Entering SYS_POWER_STATE_CPU_LPS state
(no more log)

[zephyrbot]

by Julien Delayen:

Hi Peiyang,

I did the check on my side and did not see that behavior. (make BOARD=quark_se_c1000_devboard)

I am running this test on a Quark SE board, not on a arduino 101.

Those patches are enabling the ARC feature. In order to test this, you need to:
make BOARD=quark_se_c1000_ss_devboard

Flash the x86 side with the hello world sample with CONFIG_ARC_INIT=y.
There, the application will be stuck on the second LPS as you described.

This will be fixed once GH-2604 is implemented as some support needs to be added to
the x86 when the ARC goes to sleep.

[zephyrbot]

by Sharron LIU:

With a "start_arc" binary shared by developer, I was able to verify the ARC context save/restore across deep sleep @quark_se platforms with QMSI v1.3+ ROM.
TESTPOINTs:

go to sleep via _sys_soc_set_power_state() and wake up from AONPT

suspend/resume system clock device across deep sleep

CPU and register context save/restore across deep sleep

The test case is still kept locally, as the integration test is still pending on GH-2604 to get ARC deep sleep and wake up in sync with X86 core.

Closing this. Thanks.

[zephyrbot]

by Mark Linkmeyer:

Fixing incorrect priority