Hi Miquel, On Tue, Feb 23, 2021 at 05:49:22PM +0100, Miquel Raynal wrote: > Hi Manivannan, > > Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> wrote on Mon, > 22 Feb 2021 17:32:58 +0530: > > > On a typical end product, a vendor may choose to secure some regions in > > the NAND memory which are supposed to stay intact between FW upgrades. > > The access to those regions will be blocked by a secure element like > > Trustzone. So the normal world software like Linux kernel should not > > touch these regions (including reading). > > > > So let's add a property for declaring such secure regions so that the > > driver can skip touching them. > > > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> > > --- > > Documentation/devicetree/bindings/mtd/qcom,nandc.yaml | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml b/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml > > index 84ad7ff30121..7500e20da9c1 100644 > > --- a/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml > > +++ b/Documentation/devicetree/bindings/mtd/qcom,nandc.yaml > > @@ -48,6 +48,13 @@ patternProperties: > > enum: > > - 512 > > > > + qcom,secure-regions: > > + $ref: /schemas/types.yaml#/definitions/uint32-array > > + description: > > + Regions in the NAND memory which are protected using a secure element > > + like Trustzone. This property contains the start address and size of > > + the secure regions present (optional). > > What does this "(optional)" means? If you mean the property is optional > then it should be described accordingly in the yaml file, or am I > missing something? > IIUC, if a property is not listed under "required" section then it is optional. But I've added the quote here to just make it explicit. > I wonder if it wouldn't be better to make this a NAND chip node > property. I don't think a qcom prefix is needed as potentially many > other SoCs might have the same "feature". > > I'm fine adding support for it in the qcom driver only though. > Hmm, sounds good to me. Thanks, Mani > > + > > allOf: > > - $ref: "nand-controller.yaml#" > > > > Thanks, > Miquèl
