dt-bindings: pmem: Convert binding to YAML

Convert the PMEM device tree binding from text to YAML. This will allow
device trees with pmem-region nodes to pass dtbs_check.

[iweiny: fix ups from Rob/Drew]

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Drew Fustini <drew@pdp7.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20250606184405.359812-4-drew@pdp7.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Documentation/devicetree/bindings/pmem/pmem-region.txt

@@ -1,65 +0,0 @@
-Device-tree bindings for persistent memory regions
------------------------------------------------------
-
-Persistent memory refers to a class of memory devices that are:
-
-	a) Usable as main system memory (i.e. cacheable), and
-	b) Retain their contents across power failure.
-
-Given b) it is best to think of persistent memory as a kind of memory mapped
-storage device. To ensure data integrity the operating system needs to manage
-persistent regions separately to the normal memory pool. To aid with that this
-binding provides a standardised interface for discovering where persistent
-memory regions exist inside the physical address space.
-
-Bindings for the region nodes:
------------------------------
-
-Required properties:
-	- compatible = "pmem-region"
-
-	- reg = <base, size>;
-		The reg property should specify an address range that is
-		translatable to a system physical address range. This address
-		range should be mappable as normal system memory would be
-		(i.e cacheable).
-
-		If the reg property contains multiple address ranges
-		each address range will be treated as though it was specified
-		in a separate device node. Having multiple address ranges in a
-		node implies no special relationship between the two ranges.
-
-Optional properties:
-	- Any relevant NUMA associativity properties for the target platform.
-
-	- volatile; This property indicates that this region is actually
-	  backed by non-persistent memory. This lets the OS know that it
-	  may skip the cache flushes required to ensure data is made
-	  persistent after a write.
-
-	  If this property is absent then the OS must assume that the region
-	  is backed by non-volatile memory.
-
-Examples:
---------------------
-
-	/*
-	 * This node specifies one 4KB region spanning from
-	 * 0x5000 to 0x5fff that is backed by non-volatile memory.
-	 */
-	pmem@5000 {
-		compatible = "pmem-region";
-		reg = <0x00005000 0x00001000>;
-	};
-
-	/*
-	 * This node specifies two 4KB regions that are backed by
-	 * volatile (normal) memory.
-	 */
-	pmem@6000 {
-		compatible = "pmem-region";
-		reg = < 0x00006000 0x00001000
-			0x00008000 0x00001000 >;
-		volatile;
-	};
-

Documentation/devicetree/bindings/pmem/pmem-region.yaml

@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pmem-region.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+maintainers:
+  - Oliver O'Halloran <oohall@gmail.com>
+
+title: Persistent Memory Regions
+
+description: |
+  Persistent memory refers to a class of memory devices that are:
+
+    a) Usable as main system memory (i.e. cacheable), and
+    b) Retain their contents across power failure.
+
+  Given b) it is best to think of persistent memory as a kind of memory mapped
+  storage device. To ensure data integrity the operating system needs to manage
+  persistent regions separately to the normal memory pool. To aid with that this
+  binding provides a standardised interface for discovering where persistent
+  memory regions exist inside the physical address space.
+
+properties:
+  compatible:
+    const: pmem-region
+
+  reg:
+    maxItems: 1
+
+  volatile:
+    description:
+      Indicates the region is volatile (non-persistent) and the OS can skip
+      cache flushes for writes
+    type: boolean
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    pmem@5000 {
+        compatible = "pmem-region";
+        reg = <0x00005000 0x00001000>;
+    };

MAINTAINERS

@@ -13798,7 +13798,7 @@ M:	Oliver O'Halloran <oohall@gmail.com>
 L:	nvdimm@lists.linux.dev
 S:	Supported
 Q:	https://patchwork.kernel.org/project/linux-nvdimm/list/
-F:	Documentation/devicetree/bindings/pmem/pmem-region.txt
+F:	Documentation/devicetree/bindings/pmem/pmem-region.yaml
 F:	drivers/nvdimm/of_pmem.c
 
 LIBNVDIMM: NON-VOLATILE MEMORY DEVICE SUBSYSTEM