Re: [PATCH] mtd: rawnand: Do not check for bad block if bbt is unavailable

Boris Brezillon
2021-02-03T10:20:25Z

On Wed, 03 Feb 2021 15:42:02 +0530
Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote:

> >>
> >> I got more information from the vendor, Telit. The access to the 3rd
> >partition is protected by Trustzone and any access in non privileged
> >mode (where Linux kernel runs) causes kernel panic and the device
> >reboots.

Out of curiosity, is it a per-CS-line thing or is this section
protected on all CS?

> >
> >Ok, so this is not a chip feature but more a host constraint.
> >
> >In this case it would be a good idea to add a host DT property which
> >describes the zone to avoid accessing it. Something like:
> >
> > secure-area/secure-section = <start length>;
> >
> >From the core perspective, we should parse this property early enough
> >and return -EIO when trying to access this area.

FWIW, I'm not sure making it part of the core is a good idea, at least
not until we have a different platform with a same needs. The
controller driver can parse it and return -EACCESS (or -EIO) when this
section is accessed.