How to debug with Serial Wire Viewer tracing on STM32MP15

This article does not intend to cover all STM32CubeIDE Serial Wire Viewer (SWV) capabilities; complete information is available in (UM2609), chapter 4. It only provides some setup information for STM32MP15 serie, debugging Cortex-M in Production Mode.

In that mode, the available console on the board (UART4) is used by Cortex-A Linux. The clock tree is managed by Linux and 'Trace clock' needed to setup SWO is available from Linux console with command:
awk '/ck_trace/{print $5}' /sys/kernel/debug/clk/clk_summary

In order to test, let's modify main.c file from a generated project with a looping variable 'i', as depicted hereafter.

Trace clock from Linux console

Then, setup debug configuration, enabling SWV and setting the clock: 133.25MHz here.

Debug Configuration with SWV enabled

Stopping Debug session, open Serial Wire Views: Window > Show View > Other... > SWV > SWV Trace Log & SWV Data Trace.
In SWV Trace Log > Configure Trace menu, setup Comparator 0 in order to spy variable 'i'.


SWV Setting

Then start the trace


Resuming debug session gives inside SWV Data Trace view the corresponding graphic.

SWV Data Trace Output