dt-bindings: Add a document of PECI subsystem

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

OpenBMC-Staging-Count: 2
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: Haiyue Wang <haiyue.wang@linux.intel.com>
Reviewed-by: James Feist <james.feist@linux.intel.com>
Reviewed-by: Vernon Mauery <vernon.mauery@linux.intel.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>

1 files changed, 43 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/peci/peci.txt b/Documentation/devicetree/bindings/peci/peci.txt
new file mode 100644
index 000000000000..71f26c7c6e58
--- /dev/null
+++ b/Documentation/devicetree/bindings/peci/peci.txt
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+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 = "vendor,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. According to the PECI
+	       specification, client addresses start from 0x30.
+
+Example:
+	peci-bus@0 {
+		compatible = "vendor,soc-peci";
+		reg = <0x0 0x1000>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		peci-client@30 {
+			compatible = "intel,peci-client";
+			reg = <0x30>;
+		};
+
+		peci-client@31 {
+			compatible = "intel,peci-client";
+			reg = <0x31>;
+		};
+	};