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

Miquel Raynal
2021-02-04T08:14:55Z

Hi Manivannan,

Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote on Wed,
03 Feb 2021 17:11:31 +0530:

> On 3 February 2021 4:54:22 PM IST, Boris Brezillon <boris.brezillon@collabora.com> wrote:
> >On Wed, 03 Feb 2021 16:22:42 +0530
> >Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote:
> >
> >> On 3 February 2021 3:49:14 PM IST, Boris Brezillon
> ><boris.brezillon@collabora.com> wrote:
> >> >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?
> >> >
> >>
> >> Sorry, I didn't get your question.
> >
> >The qcom controller can handle several chips, each connected through a
> >different CS (chip-select) line, right? I'm wondering if the firmware
> >running in secure mode has the ability to block access for a specific
> >CS line or if all CS lines have the same constraint. That will impact
> >the way you describe it in your DT (in one case the secure-region
> >property should be under the controller node, in the other case it
> >should be under the NAND chip node).
>
> Right. I believe the implementation is common to all NAND chips so the property should be in the controller node.

Looks weird: do you mean that each of the chips will have a secure area?