how to enable suspend to ram for arm-64 bits

[yoma sophian]

hi Sudeep

> Correct. What's the cpu enable method on your platform ? Is it PSCI ?
No, the enable method is "spin-table"

> If yes, does you PSCI implementation support SYSTEM_SUSPEND ? If yes,
> it should work. Check your PSCI implementation otherwise.

if so, there are 2 things make me curious:
a. I trace arch/arm64/kernel/psci.c even arch/arm64/*, but I sill
cannot find where it create global suspend method table with
suspend_set_ops.
# grep -rnw 'suspend_set_ops' ../linux-4.1/arch/arm64/
#
except arch/xxx folder, there are
../linux-4.1/drivers/macintosh/via-pmu.c:2276:    suspend_set_ops(&pmu_pm_ops);
../linux-4.1/drivers/acpi/sleep.c:666:    suspend_set_ops(old_suspend_ordering ?
Does that mean aarch64 register suspend_set_ops by apci flow when
adopt PSCI implementation?

b. in arm64, if some platform has its own suspend flow,  couldn't it
adopts arm/match-xxx to register its own global suspend method?

appreciate your kind help,