I’ve followed a few guides for setting up swap and updating mkinitcpio. I get the hibernate option in power management settings but it doesnt hibernate. it shutsdown like it’s going to hibernate but the session never restores. It feels like I’m missing the resume= kernel parameter but I’m not sure.
Long answer: The firmware does not support the deep sleep / hibernate functions yet.
We use the Open Source U-boot firmware, with Trusted Firmware - ARM integration.
And the Trusted Firmware - ARM integration does not yet support suspend/hibernation.
But we do hear from the TF-A developers from time to time and they are looking into it. So it might get into the next release of TF-A, which would be version 2.4.