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+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;
+ };
+