[SL-ONLY] Tracing: Energy state stats

[malbert-silabs]

Summary

This PR add two new features.

1. An optional addition to the existing tracing infrastructure to see quick statistics about the energy states

2. An optional addition to record and output all energy state transition traces for analysis with other tools.

WIP Confluence page: https://confluence.silabs.com/spaces/MATTER/pages/745094873/Energy+Mode+Tracing+and+Statistics

Related issues

Closes: https://jira.silabs.com/browse/MATTER-5331
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Testing

Added unit tests for the energy tracing feature. Uses stubs for PowerManager and CMSIS.

Tested feature on LIT-ICD app and Lighting app on series 2 and 3.
Tested on UART and RTT for the transition traces.

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code readable:

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  descriptive
• Apply the
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  rule (coding style)
• PR size is short
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See: Pull Request Guidelines

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Note

Adds optional energy mode statistics and transition tracing (with CLI and build flags), integrates power tracing init, and removes totalTaskCount from FreeRTOS task stats.

• Tracing (Silabs):
  • Energy Statistics: Track time, longest duration, and transition counts per energy mode; output via SilabsTracer::OutputPowerManagerStatistics() and shell tracing energy.
  • Energy Transition Traces: New SilabsPowerTracing singleton to record EM transitions over time and print a trace table; uses sleeptimer; one-shot timer for deferred output.
  • Config/Args: New platform/silabs/tracing/args.gni flags: silabs_tracing_energy_stats, silabs_tracing_energy_traces, silabs_tracing_energy_traces_seconds, silabs_tracing_energy_traces_max; corresponding defines emitted in SilabsTracingConfig.h.
  • Build Integration: Added SilabsPowerTracing target and deps; wired into efr32/BUILD.gn and tests group; enabled when silabs_tracing_energy_traces is set.
  • Runtime Init: Initialize SilabsPowerTracing in MatterConfig.cpp when energy traces are enabled.
• Shell:
  • Added tracing energy command to display energy mode stats.
• FreeRTOS Task Stats:
  • Removed totalTaskCount from SystemTaskStats and related log output; retained active/terminated counts.
• Tests:
  • Added unit tests for power tracing with CMSIS/Power Manager stubs; included in silabs_platform_tests.

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[Copilot]

Pull Request Overview

This PR adds optional energy state monitoring features to the tracing infrastructure for Silicon Labs platforms. The implementation provides both statistical summaries of time spent in different energy modes (EM0, EM1, EM2) and detailed transition traces for external analysis.

Key Changes

• Added statistics tracking for energy state transitions with accumulated time, longest duration, and transition counts per state
• Added optional trace recording system that captures timestamps and energy modes for later analysis
• Implemented CLI command "tracing energy" to display energy mode statistics
• Added comprehensive unit tests with mock implementations for PowerManager and CMSIS-OS2 APIs

Reviewed Changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
src/platform/silabs/tracing/SilabsPowerTracing.h	New header defining power tracing class with trace storage and callbacks
src/platform/silabs/tracing/SilabsPowerTracing.cpp	Implementation of power tracing with buffer management and timer-based output
src/platform/silabs/tracing/SilabsTracing.h	Added energy statistics tracking fields and callbacks to existing tracer
src/platform/silabs/tracing/SilabsTracing.cpp	Integrated power manager callbacks for real-time energy state monitoring
src/platform/silabs/tracing/args.gni	Build configuration for enabling energy stats and traces with configurable limits
src/platform/silabs/tracing/BUILD.gn	Added new static libraries for power tracing and test stubs
src/platform/tests/TestSilabsPowerTracing.cpp	Unit tests covering basic functionality and buffer overflow scenarios
src/platform/tests/BUILD.gn	Added power tracing test to build configuration
src/platform/silabs/tracing/mocks/*	Mock implementations of sl_power_manager and cmsis_os2 for unit testing
examples/platform/silabs/shell/tracing/TracingShellCommands.cpp	Added "energy" command to display statistics
examples/platform/silabs/MatterConfig.cpp	Initialization of power tracing system when enabled
examples/platform/silabs/FreeRTOSRuntimeStats.{h,c}	Removed unused totalTaskCount field from SystemTaskStats
src/platform/silabs/efr32/BUILD.gn	Added dependency on power tracing library when enabled

[cursor]

Bug: New Task Stats Remain Uninitialized

In vTaskCreated(), the return value from createTaskStats(handle) is discarded. The line should assign the result back to stats variable: stats = createTaskStats(handle); instead of just createTaskStats(handle);. This causes stats to remain NULL, preventing the newly created task statistics from being initialized with the current time value. Compare with vTaskMovedToReadyState() and vTaskSwitchedOut() which correctly assign the return value.

examples/platform/silabs/FreeRTOSRuntimeStats.c#L109-L118

matter_sdk/examples/platform/silabs/FreeRTOSRuntimeStats.c

Lines 109 to 118 in c756118

	{
	if (xTask == NULL)
	return;
	TaskHandle_t handle = (TaskHandle_t) xTask;
	TaskStats * stats = findTaskStats(handle);
	if (stats == NULL)
	{
	createTaskStats(handle);
	}

 

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[lpbeliveau-silabs]

Approved on resolution of comments, if an app surviving the power tracing failure is a real scenario, I would like to have a least a test that verifies every call to an un-initialized object is handled safely (note that it seems to be the case currently with the cleanup and checks on the array allocation).