Increase IPC-Stream size

Adam Lackorzynski adam at os.inf.tu-dresden.de
Thu Jun 11 23:06:54 CEST 2015


On Wed Jun 10, 2015 at 14:01:01 +0200, ba_f wrote:
> Am 2015-06-02 12:04, schrieb Matthias Lange:
> >>As i want to go for TrustZone, i dont wanna use IPC.
> >>Hence, i have to create a virtual IRQ in Ned's script, so that both
> >>Tasks know the IRQ namespace?
> >
> >No, this is not possible. You run an independent kernel and user land on
> >both the secure and non-secure side. The communication between both
> >worlds is more like a system call interface where the non-secure side
> >prepares a request and then issues the 'smc' instruction. This results
> >in a context switch to the secure side where the kernel "sees" the smc
> >instruction in form of an IRQ.
> >
> >Matthias.
> 
> 
> Ok, thank u.
> 
> i guess i'm lost without any TrustZone reference design...
> 
> 
> Anyway, one last word about my Ned script, please.
> 
> Do i really have to transfer my IRQ over IPC (in no TrustZone design)?

Yes. There's one irq, one side triggers it, the other side receives it.
Both sides need to have access to the same irq, that's why one has to
create it and give access to the other side. And that's what's done with
the IPC. 

> At least in /pkg/ned/doc/tutorial.lua there is 'Irq' mentioned as a 'useful
> constant'.
> So i guess i can define IRQ in Lua, but i miss correct syntax.

IRQs are typically not created in the lua script but on the client side
and shared with the server. See the map_irq example how it can be done.



Adam
-- 
Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/



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