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

[Harald Kipp]

Ole Reinhardt wrote:
> In which cases would we need 'enter kernel routine'? In some interrupt
> driven functions? All other driver code shold just run fine in user
> mode, does it?

At least NutEnter/ExitCritical() won't work in user mode, if I correctly
understood the ARM documents.

> For me it sounds much cleaner to run as most code as possible in user
> mode and implement such context switch functions???

Do you have any idea, what else is disabled in user mode?

Protected OSes use an exception like SWI to switch the mode. No idea how
to implement this in Nut/OS, where the kernel is a bunch of libs only.

Harald