[PATCH v4] coresight: bindings for coresight drivers

mathieu.poirier at linaro.org mathieu.poirier at linaro.org
Wed Aug 20 10:11:38 PDT 2014


From: Pratik Patel <pratikp at codeaurora.org>

Coresight IP blocks allow for the support of HW assisted tracing
on ARM SoCs.  Bindings for the currently available blocks are
presented herein.

Signed-off-by: Pratik Patel <pratikp at codeaurora.org>
Signed-off-by: Panchaxari Prasannamurthy <panchaxari.prasannamurthy at linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier at linaro.org>
---
 .../devicetree/bindings/arm/coresight.txt          | 205 +++++++++++++++++++++
 1 file changed, 205 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/coresight.txt

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
new file mode 100644
index 0000000..2ee594d
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -0,0 +1,205 @@
+* 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 : name of the component used for driver matching.  Possible values
+include: "arm,coresight-etb10", "arm,coresight-tpiu", "arm,coresight-tmc",
+"arm,coresight-funnel", and "arm,coresight-etm3x".  All of these have to
+be supplemented with "arm,primecell" as drivers are using the AMBA bus
+interface.  Since non-configurable replicators don't show up on the AMBA
+bus they don't need to be post-fixed with "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".
+
+- ports or port: The representation of the component's port layout using the
+generic DT graph presentation found in "bindings/graph.txt".
+
+Non-configurable replicators:
+
+- compatible: currently supported value is "arm-replicator".  Since non-configurable
+replicators don't show up on the AMBA hey don't need to be post-fixed with
+"arm,primecell".
+
+- id: a unique number that will identify this replicator.
+
+- ports or port: same as above.
+
+Optional properties for Sinks:
+
+- coresight-default-sink: must be specified for one of the sink devices that is
+intended to be made the default sink. Other sink devices must not have this
+specified. Not specifying this property on any of the sinks is invalid.
+
+Optional properties for ETM/PTMs:
+
+- arm,cp14: must be present if the system accesses ETM/PTM management registers
+via co-processor 14.
+
+- arm,cp14: access to ETM/PTM management registers is made via cp14.
+
+- 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: etb at 20010000 {
+		compatible = "arm,coresight-etb10", "arm,primecell";
+		reg = <0 0x20010000 0 0x1000>;
+
+		coresight-default-sink;
+		clocks = <&oscclk6a>;
+		clock-names = "apb_pclk";
+		port {
+			etb_in_port: endpoint at 0 {
+				slave-mode;
+				remote-endpoint = <&replicator_out_port0>;
+			};
+		};
+	};
+
+	tpiu: tpiu at 20030000 {
+		compatible = "arm,coresight-tpiu", "arm,primecell";
+		reg = <0 0x20030000 0 0x1000>;
+
+		clocks = <&oscclk6a>;
+		clock-names = "apb_pclk";
+		port {
+			tpiu_in_port: endpoint at 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";
+		/* this will show up in debugfs as "0.replicator" */
+		id = <0>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			/* replicator output ports */
+			port at 0 {
+				reg = <0>;
+				replicator_out_port0: endpoint {
+					remote-endpoint = <&etb_in_port>;
+				};
+			};
+
+			port at 1 {
+				reg = <1>;
+				replicator_out_port1: endpoint {
+					remote-endpoint = <&tpiu_in_port>;
+				};
+			};
+
+			/* replicator input port */
+			port at 2 {
+				reg = <0>;
+				replicator_in_port0: endpoint {
+					slave-mode;
+					remote-endpoint = <&funnel_out_port0>;
+				};
+			};
+		};
+	};
+
+	funnel at 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 at 0 {
+				reg = <0>;
+				funnel_out_port0: endpoint {
+					remote-endpoint = <&replicator_in_port0>;
+				};
+			};
+
+			/* funnel input ports */
+			port at 1 {
+				reg = <0>;
+				funnel_in_port0: endpoint {
+					slave-mode;
+					remote-endpoint = <&ptm0_out_port>;
+				};
+			};
+
+			port at 2 {
+				reg = <1>;
+				funnel_in_port1: endpoint {
+					slave-mode;
+					remote-endpoint = <&ptm1_out_port>;
+				};
+			};
+
+			port at 3 {
+				reg = <2>;
+				funnel_in_port2: endpoint {
+					slave-mode;
+					remote-endpoint = <&etm0_out_port>;
+				};
+			};
+
+		};
+	};
+
+3. Sources
+	ptm0: ptm at 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>;
+			};
+		};
+	};
+
+	ptm1: ptm at 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>;
+			};
+		};
+	};
-- 
1.9.1




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