[v4 01/11] dt-bindings: Add a document of PECI subsystem

[Jae Hyun Yoo]

This commit adds a document of generic PECI bus, adapter and client
driver.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx>
Reviewed-by: James Feist <james.feist@xxxxxxxxxxxxxxx>
Reviewed-by: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>
Cc: Andrew Jeffery <andrew@xxxxxxxx>
Cc: Joel Stanley <joel@xxxxxxxxx>
---
 .../devicetree/bindings/peci/peci.txt         | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/peci/peci.txt

diff --git a/Documentation/devicetree/bindings/peci/peci.txt b/Documentation/devicetree/bindings/peci/peci.txt
new file mode 100644
index 000000000000..72fc8ddd6a55
--- /dev/null
+++ b/Documentation/devicetree/bindings/peci/peci.txt
@@ -0,0 +1,59 @@
+Generic device tree configuration for PECI buses
+================================================
+
+Required properties:
+- compatible     : Should be "simple-bus".
+- #address-cells : Should be present if the device has sub-nodes.
+- #size-cells    : Should be present if the device has sub-nodes.
+- ranges         : Should contain PECI controller registers ranges.
+
+Example:
+	peci: peci@10000000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x0 0x10000000 0x1000>;
+	};
+
+Generic device tree configuration for PECI adapters
+===================================================
+
+Required properties:
+- #address-cells : Should be <1>. Read more about client addresses below.
+- #size-cells    : Should be <0>. Read more about client addresses below.
+
+The cells properties above define that an address of CPU clients of a PECI bus
+are described by a single value.
+
+Example:
+	peci0: peci-bus@0 {
+		compatible = "soc,soc-peci";
+		reg = <0x0 0x1000>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+	};
+
+Generic device tree configuration for PECI clients
+==================================================
+
+Required properties:
+- compatible : Should contain name of PECI client.
+- reg        : Should contain address of a client CPU. Address range of CPU
+	       clients is starting from 0x30 based on PECI specification.
+
+Example:
+	peci-bus@0 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		< more properties >
+
+		function@30 {
+			compatible = "device,function";
+			reg = <0x30>;
+		};
+
+		function@31 {
+			compatible = "device,function";
+			reg = <0x31>;
+		};
+	};
-- 
2.17.0