[En-Nut-Discussion] arm port (RFC: Changing ARM mode)

Alain M. alainm at pobox.com
Tue Jan 13 19:39:25 CET 2009

Rocendo Bracamontes del toro escreveu:
>   void NutSleep (uint32_t ms)
>    {
>        ENTRY_KERNEL_MODE(); // change mode to supervisor when applicable
>       ..... code execute at kernel level here ....
>        EXIT_KERNEL_MODE(); exit supervisor mode, enter user mode when
> applicable
>   }

I am no expert in the matter, but in my undertanding this is not very 
good. The problem is that SWI is a CALL, not a command has one parameter 
for the function and parametters have to be fetch from the user stack. 
This calls for an entire different achitecture.


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