[v2,1/5] dt-bindings: nvmem: Add bindings for rmem driver

Commit Message

Nicolas Saenz Julienne Dec. 18, 2020, 3:43 p.m. UTC

Firmware/co-processors might use reserved memory areas in order to pass
data stemming from an nvmem device otherwise non accessible to Linux.
For example an EEPROM memory only physically accessible to firmware, or
data only accessible early at boot time.

Introduce the dt-bindings to nvmem's rmem.

Signed-off-by: Nicolas Saenz Julienne <[e-mail]>

---

Changes since v1:
 - Update schema to new driver design

 .../devicetree/bindings/nvmem/rmem.yaml       | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/rmem.yaml

Comments

Rob Herring Dec. 21, 2020, 4:10 p.m. UTC | #1

On Fri, 18 Dec 2020 16:43:16 +0100, Nicolas Saenz Julienne wrote:
> Firmware/co-processors might use reserved memory areas in order to pass
> data stemming from an nvmem device otherwise non accessible to Linux.
> For example an EEPROM memory only physically accessible to firmware, or
> data only accessible early at boot time.
> 
> Introduce the dt-bindings to nvmem's rmem.
> 
> Signed-off-by: Nicolas Saenz Julienne <[e-mail]>
> 
> ---
> 
> Changes since v1:
>  - Update schema to new driver design
> 
>  .../devicetree/bindings/nvmem/rmem.yaml       | 49 +++++++++++++++++++
>  1 file changed, 49 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/nvmem/rmem.yaml
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:
./Documentation/devicetree/bindings/nvmem/rmem.yaml:19:9: [warning] wrong indentation: expected 10 but found 8 (indentation)

dtschema/dtc warnings/errors:

See https://patchwork.ozlabs.org/patch/1418470

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.

Patch

diff --git a/Documentation/devicetree/bindings/nvmem/rmem.yaml b/Documentation/devicetree/bindings/nvmem/rmem.yaml
new file mode 100644
index 000000000000..29b53871aa02
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/rmem.yaml
@@ -0,0 +1,49 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/nvmem/rmem.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Reserved Memory Based nvmem Device
+
+maintainers:
+  - Nicolas Saenz Julienne <[e-mail]>
+
+allOf:
+  - $ref: "nvmem.yaml#"
+
+properties:
+  compatible:
+    items:
+      - enum:
+        - raspberrypi,bootloader-config
+      - const: nvmem-rmem
+
+  no-map:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      Avoid creating a virtual mapping of the region as part of the OS'
+      standard mapping of system memory.
+
+required:
+  - compatible
+  - no-map
+
+unevaluatedProperties: false
+
+examples:
+  - |
+        reserved-memory {
+                #address-cells = <1>;
+                #size-cells = <1>;
+
+                blconfig: nvram@10000000 {
+                        compatible = "raspberrypi,bootloader-config", "nvmem-rmem";
+                        #address-cells = <1>;
+                        #size-cells = <1>;
+                        reg = <0x10000000 0x1000>;
+                        no-map;
+                };
+        };
+
+...