Re: [RFC PATCHv2 0/4] Support for OTP memory

Jamie Iles
2011-03-24T17:47:30Z

Hi Mike,

On Thu, Mar 24, 2011 at 01:39:56PM -0400, Mike Frysinger wrote:
> On Thu, Mar 24, 2011 at 11:21, Jamie Iles wrote:
> > Following some feedback from Greg, I've updated this series to be more
> > of a generic OTP layer.  Everything is now registered under the "otp"
> > bus and I've also converted the blackfin OTP driver to use this
> > framework (which is the only current OTP driver I could find).
>
> really, i'm the only one who wrote a driver ? that's boring.

Yes, and I'm quite surprised at that. Perhaps I've missed some.

> i guess this isnt trying to handle OTP stuff that exists in the MTD
> layer already ?

No, I believe that the OTP stuff in the MTD layer is where some flash
chips have a small section that can be write protected so it's more like
a permanent write disable to that sector whereas the thing I'm looking
at is on a per-bit basis.

I did have a look at if there was some kind of way to fit this stuff
into the MTD layer but it felt like it was really shoehorning it in.

> > Mike, I wasn't 100% sure how big the blackfin OTP is but I found a
> > datasheet talking about 64KB so I've assumed that for now.
>
> the datasheets say 64K *bits* :). i think all our datasheets tend to
> use bits rather than bytes because they're stupid and bigger numbers
> always means better parts !

That sounds very familiar!

Jamie