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System suspend (A83T)

I have been working on addin support for system suspend to A83T. The code for that is integrated into my linux/tbs tree, and into my crust firmare tree.

System suspend is done on multiple levels:

Management firmware (crust) then loops and watches for wakeup interrupts and restores the system into running state if necessary.

At the moment, the status is that Linux side is fairly complete. Crust receives the suspend message but ignores it, and Linux puts the last core into WFI.

If the interrupts happens, it is handled by the Linux kernel when the last ARM core exits WFI.

More work needs to be done, to save power during suspend. With the above method, the system consumes about 900mW in suspended sta­te.