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From:   Vincent Whitchurch <vincent.whitchurch@axis.com>
To:     <vigneshr@ti.com>, <richard@nod.at>, <miquel.raynal@bootlin.com>,
        <joern@lazybastard.org>
CC:     <kernel@axis.com>,
        Vincent Whitchurch <vincent.whitchurch@axis.com>,
        <linux-mtd@lists.infradead.org>, <devicetree@vger.kernel.org>,
        <robh+dt@kernel.org>, <krzk+dt@kernel.org>,
        <frowand.list@gmail.com>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v2 2/4] dt-bindings: reserved-memory: Add phram
Date:   Tue, 5 Apr 2022 15:03:48 +0200
Message-ID: <20220405130350.1640985-3-vincent.whitchurch@axis.com>
In-Reply-To: <20220405130350.1640985-1-vincent.whitchurch@axis.com>
References: <20220405130350.1640985-1-vincent.whitchurch@axis.com>
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Add bindings to allow MTD/block devices to be created in reserved-memory
regions using the "phram" driver.

This allows things like partitioning to be specified via the existing
devicetree bindings.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
---

Notes:
    v2:
    - Add note on what "phram" means.
    - Use /schemas/mtd/mtd.yaml instead of relative pathUse /schemas/mtd/mtd.yaml instead of relative path.

 .../bindings/reserved-memory/phram.yaml       | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/reserved-memory/phram.yaml

diff --git a/Documentation/devicetree/bindings/reserved-memory/phram.yaml b/Documentation/devicetree/bindings/reserved-memory/phram.yaml
new file mode 100644
index 000000000000..318415b56afe
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/phram.yaml
@@ -0,0 +1,47 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/reserved-memory/phram.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MTD/block device in RAM
+
+description: |
+  Use the reserved memory region as an MTD or block device.  The "phram" node
+  is named after the "MTD in PHysical RAM" driver which provides an
+  implementation of this functionality in Linux.
+
+  If no-map is not set, cached mappings will be used for the memory region.
+
+maintainers:
+  - Vincent Whitchurch <vincent.whitchurch@axis.com>
+
+allOf:
+  - $ref: "reserved-memory.yaml"
+  - $ref: "/schemas/mtd/mtd.yaml"
+
+properties:
+  compatible:
+    const: phram
+
+  reg:
+    description: region of memory that contains the MTD/block device
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    reserved-memory {
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        phram: flash@12340000 {
+            compatible = "phram";
+            label = "rootfs";
+            reg = <0x12340000 0x00800000>;
+        };
+    };
-- 
2.34.1