Re: [PATCH v5 2/3] dt-bindings: mtd: qcom_nandc: document qcom,boot-partitions binding

Ansuel Smith
2022-06-09T10:26:01Z

On Thu, Jun 09, 2022 at 12:50:29PM +0530, Manivannan Sadhasivam wrote:
> On Wed, Jun 08, 2022 at 02:10:29AM +0200, Ansuel Smith wrote:
> > Document new qcom,boot-partition binding used to apply special
> > read/write layout to boot partitions.
> >
> > QCOM apply a special layout where spare data is not protected
> > by ECC for some special pages (used for boot partition). Add
> > Documentation on how to declare these special pages.
> >
> > Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> > ---
> > .../devicetree/bindings/mtd/qcom,nandc.yaml | 26 +++++++++++++++++++
> > 1 file changed, 26 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml b/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml
> > index 84ad7ff30121..a0914ccb95b0 100644
> > --- a/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml
> > +++ b/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml
> > @@ -102,6 +102,30 @@ allOf:
> > - const: rx
> > - const: cmd
> >
> > + - if:
> > + properties:
> > + compatible:
> > + contains:
> > + enum:
> > + - qcom,ipq806x-nand
> > +
> > + then:
> > + properties:
> > + qcom,boot-partitions:
> > + $ref: /schemas/types.yaml#/definitions/uint32-matrix
>
> Wondering if u32 is enough for covering all ranges? Other than this,
>
> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
>
> Thanks,
> Mani
>

I mean they are offset and sizes... Considering it's an old SoC and max
nand mounted is 1g we should be safe with u32.

> > + items:
> > + items:
> > + - description: offset
> > + - description: size
> > + description:
> > + Boot partition use a different layout where the 4 bytes of spare
> > + data are not protected by ECC. Use this to declare these special
> > + partitions by defining first the offset and then the size.
> > +
> > + It's in the form of <offset1 size1 offset2 size2 offset3 ...>
> > +
> > + Refer to the ipq8064 example on how to use this special binding.
> > +
> > required:
> > - compatible
> > - reg
> > @@ -135,6 +159,8 @@ examples:
> > nand-ecc-strength = <4>;
> > nand-bus-width = <8>;
> >
> > + qcom,boot-partitions = <0x0 0x58a0000>;
> > +
> > partitions {
> > compatible = "fixed-partitions";
> > #address-cells = <1>;
> > --
> > 2.36.1
> >
>
> --
> மணிவண்ணன் சதாசிவம்

--
Ansuel