[PATCH v7 2/3] dt-bindings: mtd: Add a property to declare secure regions in NAND chips

Manivannan Sadhasivam
2021-03-19T15:01:15Z

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
drivers can skip touching them.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
Documentation/devicetree/bindings/mtd/nand-controller.yaml | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/mtd/nand-controller.yaml b/Documentation/devicetree/bindings/mtd/nand-controller.yaml
index d0e422f4b3e0..678b39952502 100644
--- a/Documentation/devicetree/bindings/mtd/nand-controller.yaml
+++ b/Documentation/devicetree/bindings/mtd/nand-controller.yaml
@@ -143,6 +143,13 @@ patternProperties:
Ready/Busy pins. Active state refers to the NAND ready state and
should be set to GPIOD_ACTIVE_HIGH unless the signal is inverted.

+ secure-regions:
+ $ref: /schemas/types.yaml#/definitions/uint64-matrix
+ description:
+ Regions in the NAND chip which are protected using a secure element
+ like Trustzone. This property contains the start address and size of
+ the secure regions present.
+
required:
- reg

--
2.25.1