[PATCH v2] dt-bindings: firmware: xilinx: Describe soc-nvmem subnode

[Michal Simek]

Describe soc-nvmem subnode as the part of firmware node. The name can't be
pure nvmem because dt-schema already defines it as array property that's
why different name should be used.

Signed-off-by: Michal Simek <michal.simek at amd.com>
---

Changes in v2:
- Fix typo in subject
- Make example bigger requested by Conor

Dt binding for nvmem node has been already merged and it is the part of
linux-next tree.
Here is the reference to it just in case:
https://lore.kernel.org/r/170635581622.41421.8980881999042944764.b4-ty@linaro.org

v1 available here:
https://lore.kernel.org/r/3869498c995cbb123127122f429e90de0a3f4014.1706531104.git.michal.simek@amd.com

---
 .../firmware/xilinx/xlnx,zynqmp-firmware.yaml  | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.yaml b/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.yaml
index 870b94813a43..741f17c830f4 100644
--- a/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.yaml
+++ b/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.yaml
@@ -62,6 +62,12 @@ properties:
       interface.
     type: object
 
+  soc-nvmem:
+    $ref: /schemas/nvmem/xlnx,zynqmp-nvmem.yaml#
+    description: The ZynqMP MPSoC provides access to the hardware related data
+      like SOC revision, IDCODE and specific purpose efuses.
+    type: object
+
   pcap:
     $ref: /schemas/fpga/xlnx,zynqmp-pcap-fpga.yaml#
     description: The ZynqMP SoC uses the PCAP (Processor Configuration Port) to
@@ -110,6 +116,18 @@ examples:
     firmware {
       zynqmp_firmware: zynqmp-firmware {
         #power-domain-cells = <1>;
+        soc-nvmem {
+          compatible = "xlnx,zynqmp-nvmem-fw";
+          nvmem-layout {
+            compatible = "fixed-layout";
+            #address-cells = <1>;
+            #size-cells = <1>;
+
+            soc_revision: soc-revision at 0 {
+                reg = <0x0 0x4>;
+            };
+          };
+        };
         gpio {
           compatible = "xlnx,zynqmp-gpio-modepin";
           gpio-controller;
-- 
2.36.1