> From: Russell King - ARM Linux [mailto:li...@arm.linux.org.uk]
> Sent: Monday, May 18, 2009 3:25 PM

> The call to the enter method essentially calls the core specific suspend
> function (eg, pxa25x_cpu_suspend()), which is an assembly function which
> ultimately ends up powering down the core resulting in full loss of state
> in the CPU.  We seem to be able to avoid having to save the exception mode
> registers there.
>
> The same thing is done with sa11x0 and Samsung SoCs.
>
> I don't see any reason for OMAP to be "special" in this regard.

The code flow is:
        - Wakeup event
        - ARM reboots and uses SOC mask ROM context restore helper
        - Mask ROM code jump to restore pointers with MMU OFF.
        - Restore code resets ARM CortexA8 state
        -*- Trustzone SMI calls are made to restore some secure state
        - Jump back from SRAM to C code

The dangling question to me is if any of the cpu state is needed by the 
trustzone monitor code as a precondition.  The doc's I have led me to believe 
its ok, but I've not verified this.

Regards,
Richard W.

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