coresight.txt

* CoreSight Components:

CoreSight components are compliant with the ARM CoreSight architecture
specification and can be connected in various topologies to suit a particular
SoCs tracing needs. These trace components can generally be classified as
sinks, links and sources. Trace data produced by one or more sources flows
through the intermediate links connecting the source to the currently selected
sink. Each CoreSight component device should use these properties to describe
its hardware characteristcs.

* Required properties for all components *except* non-configurable replicators:

	* compatible: These have to be supplemented with "arm,primecell" as
	  drivers are using the AMBA bus interface.  Possible values include:
		- "arm,coresight-etb10", "arm,primecell";
		- "arm,coresight-tpiu", "arm,primecell";
		- "arm,coresight-tmc", "arm,primecell";
		- "arm,coresight-funnel", "arm,primecell";
		- "arm,coresight-etm3x", "arm,primecell";

	* reg: physical base address and length of the register
	  set(s) of the component.

	* clocks: the clock associated to this component.

	* clock-names: the name of the clock as referenced by the code.
	  Since we are using the AMBA framework, the name should be
	  "apb_pclk".

	* port or ports: The representation of the component's port
	  layout using the generic DT graph presentation found in
	  "bindings/graph.txt".

* Required properties for devices that don't show up on the AMBA bus, such as
  non-configurable replicators:

	* compatible: Currently supported value is (note the absence of the
	  AMBA markee):
		- "arm,coresight-replicator"

	* port or ports: same as above.

* Optional properties for ETM/PTMs:

	* arm,cp14: must be present if the system accesses ETM/PTM management
	  registers via co-processor 14.

	* cpu: the cpu phandle this ETM/PTM is affined to. When omitted the
	  source is considered to belong to CPU0.

* Optional property for TMC:

	* arm,buffer-size: size of contiguous buffer space for TMC ETR
	 (embedded trace router)


Example:

1. Sinks
	etb@20010000 {
		compatible = "arm,coresight-etb10", "arm,primecell";
		reg = <0 0x20010000 0 0x1000>;

		clocks = <&oscclk6a>;
		clock-names = "apb_pclk";
		port {
			etb_in_port: endpoint@0 {
				slave-mode;
				remote-endpoint = <&replicator_out_port0>;
			};
		};
	};

	tpiu@20030000 {
		compatible = "arm,coresight-tpiu", "arm,primecell";
		reg = <0 0x20030000 0 0x1000>;

		clocks = <&oscclk6a>;
		clock-names = "apb_pclk";
		port {
			tpiu_in_port: endpoint@0 {
				slave-mode;
				remote-endpoint = <&replicator_out_port1>;
			};
		};
	};

2. Links
	replicator {
		/* non-configurable replicators don't show up on the
		 * AMBA bus.  As such no need to add "arm,primecell".
		 */
		compatible = "arm,coresight-replicator";

		ports {
			#address-cells = <1>;
			#size-cells = <0>;

			/* replicator output ports */
			port@0 {
				reg = <0>;
				replicator_out_port0: endpoint {
					remote-endpoint = <&etb_in_port>;
				};
			};

			port@1 {
				reg = <1>;
				replicator_out_port1: endpoint {
					remote-endpoint = <&tpiu_in_port>;
				};
			};

			/* replicator input port */
			port@2 {
				reg = <0>;
				replicator_in_port0: endpoint {
					slave-mode;
					remote-endpoint = <&funnel_out_port0>;
				};
			};
		};
	};

	funnel@20040000 {
		compatible = "arm,coresight-funnel", "arm,primecell";
		reg = <0 0x20040000 0 0x1000>;

		clocks = <&oscclk6a>;
		clock-names = "apb_pclk";
		ports {
			#address-cells = <1>;
			#size-cells = <0>;

			/* funnel output port */
			port@0 {
				reg = <0>;
				funnel_out_port0: endpoint {
					remote-endpoint =
							<&replicator_in_port0>;
				};
			};

			/* funnel input ports */
			port@1 {
				reg = <0>;
				funnel_in_port0: endpoint {
					slave-mode;
					remote-endpoint = <&ptm0_out_port>;
				};
			};

			port@2 {
				reg = <1>;
				funnel_in_port1: endpoint {
					slave-mode;
					remote-endpoint = <&ptm1_out_port>;
				};
			};

			port@3 {
				reg = <2>;
				funnel_in_port2: endpoint {
					slave-mode;
					remote-endpoint = <&etm0_out_port>;
				};
			};

		};
	};

3. Sources
	ptm@2201c000 {
		compatible = "arm,coresight-etm3x", "arm,primecell";
		reg = <0 0x2201c000 0 0x1000>;

		cpu = <&cpu0>;
		clocks = <&oscclk6a>;
		clock-names = "apb_pclk";
		port {
			ptm0_out_port: endpoint {
				remote-endpoint = <&funnel_in_port0>;
			};
		};
	};

	ptm@2201d000 {
		compatible = "arm,coresight-etm3x", "arm,primecell";
		reg = <0 0x2201d000 0 0x1000>;

		cpu = <&cpu1>;
		clocks = <&oscclk6a>;
		clock-names = "apb_pclk";
		port {
			ptm1_out_port: endpoint {
				remote-endpoint = <&funnel_in_port1>;
			};
		};
	};