[PATCH 06/11] dts: bindings: Document device tree bindings for ETE
From: Anshuman Khandual
Date: Wed Dec 23 2020 - 05:05:52 EST
From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Document the device tree bindings for Embedded Trace Extensions.
ETE can be connected to legacy coresight components and thus
could optionally contain a connection graph as described by
the CoreSight bindings.
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
Documentation/devicetree/bindings/arm/ete.txt | 41 +++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/ete.txt
diff --git a/Documentation/devicetree/bindings/arm/ete.txt b/Documentation/devicetree/bindings/arm/ete.txt
new file mode 100644
index 0000000..b52b507
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/ete.txt
@@ -0,0 +1,41 @@
+Arm Embedded Trace Extensions
+
+Arm Embedded Trace Extensions (ETE) is a per CPU trace component that
+allows tracing the CPU execution. It overlaps with the CoreSight ETMv4
+architecture and has extended support for future architecture changes.
+The trace generated by the ETE could be stored via legacy CoreSight
+components (e.g, TMC-ETR) or other means (e.g, using a per CPU buffer
+Arm Trace Buffer Extension (TRBE)). Since the ETE can be connected to
+legacy CoreSight components, a node must be listed per instance, along
+with any optional connection graph as per the coresight bindings.
+See bindings/arm/coresight.txt.
+
+** ETE Required properties:
+
+- compatible : should be one of:
+ "arm,embedded-trace-extensions"
+
+- cpu : the CPU phandle this ETE belongs to.
+
+** Optional properties:
+- CoreSight connection graph, see bindings/arm/coresight.txt.
+
+** Example:
+
+ete_0 {
+ compatible = "arm,embedded-trace-extension";
+ cpu = <&cpu_0>;
+};
+
+ete_1 {
+ compatible = "arm,embedded-trace-extension";
+ cpu = <&cpu_1>;
+
+ out-ports { /* legacy CoreSight connection */
+ port {
+ ete1_out_port: endpoint@0 {
+ remote-endpoint = <&funnel_in_port0>;
+ };
+ };
+ };
+};
--
2.7.4