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Hello,
I'm a student and I'm interested in how to compare ACPI Sleep States (Sx) and processor power states (Cx) with ARM Cortex-A states e.g. Standby, Retention, Power Down, Dormant Mode, Hotplug, Stop, Deep Sleep
Thank you
what metrics do you want?
Anyway, the power state of Cortex-A is SoC specific.
Cortex-A only outputs STANDBYWFI or STANDBYWFE signal according to execution of WFI or WFE instruction.
Although CPU will enter the sleep mode (i.e clock stopping) by WFI or WFE, the further power management is responsible to SoC vendors.
An SoC vendor can implement several power states by using STANDBYWFI or STANDBYWFE signals.
If you want to compare power modes, at first you have to select an SoC of which CPU is Cortex-A7.
Best regards,
Yasuhiko Koumoto.