[PATCH 00/15] OMAP SHAM & AES Crypto Updates
Paul Walmsley
paul at pwsan.com
Fri Feb 1 12:35:05 EST 2013
Hi Mark
On Mon, 28 Jan 2013, Mark A. Greer wrote:
> On Thu, Jan 17, 2013 at 03:27:28PM -0700, Mark A. Greer wrote:
> > On Thu, Jan 17, 2013 at 07:13:36PM +0000, Paul Walmsley wrote:
> > > On Tue, 8 Jan 2013, Mark A. Greer wrote:
> > >
> > > > On Sun, Dec 23, 2012 at 08:40:43AM +0000, Paul Walmsley wrote:
>
> > > What do you think about adding an am35xx_es11plus_hwmod_ocp_ifs[] array to
> > > omap_hwmod_3xxx_data.c for these secure hwmods? That carries the implicit
> > > and possibly wrong assumption that it's likely to be ES1.0 devices that
> > > are missing the SHAM/AES, but it seems unlikely that TI would have
> > > multiple silicon revs running around claiming to be ES1.1? Or maybe I'm
> > > just being naïve.
> >
> > Something like that makes sense to me. I'll re-read my email, etc. and
> > see if I can find something to help us figure it out.
>
> I couldn't find any information that helped with this so AFAIK there is no
> good way to tell if a particular am35xx has the crypto hardware available
> or not.
I was thinking that we might assume that they are present on AM35xx
ES1.1+. If the TI folks are saying that they aren't available on only a
few early devices, I'd guess that means ES1.0. I personally have never
seen an ES1.0 AM35xx device...
Discriminating between ES1.0 and ES1.1+ should be pretty easy in the hwmod
init...
> At this point, I vote for moving 'omap3xxx_l4_core__sham' and
> 'omap3xxx_l4_core__aes' from omap3xxx_gp_hwmod_ocp_ifs[] and putting them
> in omap34xx_hwmod_ocp_ifs[] and omap36xx_hwmod_ocp_ifs[].
I'm pretty sure that's going to break on HS OMAPs, like the HS OMAP3430 in
the N900. I don't think those IP blocks are directly accessible from
Linux on most HS setups, although this might vary by device. I'd feel
more comfortable if you created an omap34xx_gp_hwmod_ocp_ifs[] list and an
omap36xx_gp_hwmod_ocp_ifs[] list. We should probably get rid of
omap3xxx_gp_hwmod_ocp_ifs[] altogether.
> That should be safe in general and if someone with an am35xx wants to
> use those modules, they can edit am35xx_hwmod_ocp_ifs[] locally.
If you want to just leave them commented in am35xx_hwmod_ocp_ifs[], rather
than enabling them for ES1.1+ AM35xx, that's fine with me too, since we
don't know that they are ES-level-based. Maybe put a comment there that
says that these are likely to be present, but no one seems to know for
certain? Seems ludicrous, but I guess that's what we're reduced to!
- Paul
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