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From 15cfca011ac1e08e073628b36f40d64f03fcf2b2 Mon Sep 17 00:00:00 2001
From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Date: Thu, 10 Dec 2020 19:22:45 +0100
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.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

---

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

--- /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;
+                };
+        };
+
+...