[PATCH v8 1/7] dt-bindings: arm: coresight-tmc: Add "memory-region" property

Linu Cherian lcherian at marvell.com
Thu May 30 21:27:39 PDT 2024


memory-region 0: Reserved trace buffer memory

  TMC ETR: When available, use this reserved memory region for
  trace data capture. Same region is used for trace data
  retention after a panic or watchdog reset.

  TMC ETF: When available, use this reserved memory region for
  trace data retention synced from internal SRAM after a panic or
  watchdog reset.

memory-region 1: Reserved meta data memory

  TMC ETR, ETF: When available, use this memory for register
  snapshot retention synced from hardware registers after a panic
  or watchdog reset.

Reviewed-by: Rob Herring <robh at kernel.org>
Signed-off-by: Linu Cherian <lcherian at marvell.com>
---
 .../bindings/arm/arm,coresight-tmc.yaml       | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
index cb8dceaca70e..4787d7c6bac2 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
@@ -101,6 +101,29 @@ properties:
           and ETF configurations.
         $ref: /schemas/graph.yaml#/properties/port
 
+  memory-region:
+    items:
+      - description: Reserved trace buffer memory for ETR and ETF sinks.
+          For ETR, this reserved memory region is used for trace data capture.
+          Same region is used for trace data retention as well after a panic
+          or watchdog reset.
+          This reserved memory region is used as trace buffer or used for trace
+          data retention only if specifically selected by the user in sysfs
+          interface.
+          The default memory usage models for ETR in sysfs/perf modes are
+          otherwise unaltered.
+
+          For ETF, this reserved memory region is used by default for
+          retention of trace data synced from internal SRAM after a panic
+          or watchdog reset.
+      - description: Reserved meta data memory. Used for ETR and ETF sinks
+          for storing metadata.
+
+  memory-region-names:
+    items:
+      - const: tracedata
+      - const: metadata
+
 required:
   - compatible
   - reg
@@ -115,6 +138,9 @@ examples:
     etr at 20070000 {
         compatible = "arm,coresight-tmc", "arm,primecell";
         reg = <0x20070000 0x1000>;
+        memory-region = <&etr_trace_mem_reserved>,
+                       <&etr_mdata_mem_reserved>;
+        memory-region-names = "tracedata", "metadata";
 
         clocks = <&oscclk6a>;
         clock-names = "apb_pclk";
-- 
2.34.1




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