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From: Michal Simek <michal.simek@amd.com>
To: <linux-kernel@vger.kernel.org>, <monstr@monstr.eu>,
	<michal.simek@xilinx.com>, <git@xilinx.com>
CC: Conor Dooley <conor+dt@kernel.org>, Greg Kroah-Hartman
	<gregkh@linuxfoundation.org>, Jiri Slaby <jirislaby@kernel.org>, Krzysztof
 Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Rob Herring
	<robh+dt@kernel.org>, <devicetree@vger.kernel.org>,
	<linux-serial@vger.kernel.org>
Subject: [PATCH] dt-bindings: serial: Describe ARM dcc interface
Date: Thu, 21 Dec 2023 15:05:09 +0100
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Debug Communication Channel (DCC) provides the way how to pass data between
target CPU and host via JTAG interface. Every CPU has own interface for
communication via dbgdtrtx_el0 and dbgdtrrx_el0 registers.

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

This communication interface is used for flash programming on Xilinx
SOCs from U-Boot.
https://source.denx.de/u-boot/u-boot/-/blob/master/drivers/serial/arm_dcc.c

---
 .../devicetree/bindings/serial/arm,dcc.yaml   | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/serial/arm,dcc.yaml

diff --git a/Documentation/devicetree/bindings/serial/arm,dcc.yaml b/Documentation/devicetree/bindings/serial/arm,dcc.yaml
new file mode 100644
index 000000000000..fd0589356617
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/arm,dcc.yaml
@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/arm,dcc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ARM DCC (Data communication channel) serial emulation
+
+maintainers:
+  - Michal Simek <michal.simek@amd.com>
+
+description: |
+  ARM DCC (Data communication channel) serial emulation interface available
+  via JTAG can be also used as one of serial line tightly coupled with every
+  ARM CPU available in the system.
+
+properties:
+  compatible:
+    const: arm,dcc
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    serial {
+      compatible = "arm,dcc";
+    };
-- 
2.36.1