From f90714e56cb6c5d1e57fb4385b107932f76ef94f Mon Sep 17 00:00:00 2001
From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Date: Fri, 29 Jan 2021 17:14:28 +0000
Subject: [PATCH] dt-bindings: nvmem: Add bindings for rmem driver

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.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210129171430.11328-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 .../devicetree/bindings/nvmem/rmem.yaml       | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/rmem.yaml

diff --git a/Documentation/devicetree/bindings/nvmem/rmem.yaml b/Documentation/devicetree/bindings/nvmem/rmem.yaml
new file mode 100644
index 000000000000..1d85a0a30846
--- /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 <nsaenzjulienne@suse.de>
+
+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;
+                };
+        };
+
+...