[PATCH] nvmem: ocotp: add support to revoke keys

[sha at pengutronix.de]

On Tue, Mar 16, 2021 at 08:03:01AM +0000, Denis Osterland-Heim wrote:
> Hi Sascha,
> 
> Am Montag, den 15.03.2021, 09:04 +0100 schrieb Sascha Hauer:
> > Hi Denis,
> >
> > On Fri, Mar 12, 2021 at 02:39:40PM +0000, Denis Osterland-Heim wrote:
> > > Hi,
> > >
> > > It would be no problem to do it in a script.
> > > I did it as a fist prove of concept.
> > > My opinion is, that this hard coded implementation give stronger
> > > guarantee that this code is really executed.
> >
> > You could also create a C function which you call from your board code.
> good Idea
> 
> >
> > >
> > > I would love to implement the HAB to check FIT signatures,
> > > but with MMU enabled it will not work AFAIK and code requiring MMU disabled is not welcome.
> >
> > Are you sure it doesn't work? What I know is that the jump table for the
> > HAB function is placed in the zero page which is set to faulting
> > normally when the MMU is enabled. If that's the only problem we could
> > solve that.
> I would like to give it a try.
> 
> enable CONFIG_ARCH_HAS_ZERO_PAGE
> 
> zero_page_access();
> pvt->some_function();
> zero_page_faulting();
> 
> right?

Yes, right.

Sascha

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