Add Documentation for linux,usable-memory
Signed-off-by: Abhishek Tiwari <[email protected]>
---
.../bindings/linux,usable-memory.txt | 32 +++++++++++++++++++
1 file changed, 32 insertions(+)
create mode 100644 Documentation/devicetree/bindings/linux,usable-memory.txt
diff --git a/Documentation/devicetree/bindings/linux,usable-memory.txt
b/Documentation/devicetree/bindings/linux,usable-memory.txt
new file mode 100644
index 000000000000..167054d2e9a2
--- /dev/null
+++ b/Documentation/devicetree/bindings/linux,usable-memory.txt
@@ -0,0 +1,32 @@
+linux,usable-memory
+===================
+
+Description
+-----------
+The ``linux,usable-memory`` property can be used to restrict usable memory
+region. This property holds a base address and size, Memory outside of this
+range is not accessible by the kernel. This property is particularly useful
+in specialized hardware platforms where certain memory regions must be
+reserved for specific use.
+
+Common use cases include:
+- Allocating ``ramoops`` region
+- Reserving memory for hardware-specific needs
+- Fake Protecting persistent memory (PMEM)
+
+Valid memory may be sparse within the specified range.
+An example device tree configuration is shown below:
+
+.. code-block:: dts
+/ {
+ &memory {
+ linux,usable-memory = <
+ 0x00000000 0x80000000 0x00000000 0x1BA00000
+ 0x00000000 0xA1000000 0x00000000 0x2AC00000
+ >;
+ };
+};
+
+While this property does not represent a real hardware, the address
+and the size are expressed in #address-cells and #size-cells,
+respectively, of the root node.
--
2.48.1
