How to debug with Serial Wire Viewer tracing on STM32MP15

This article does not intend to cover all STM32CubeIDE Serial Wire Viewer (SWV) capabilities. It only provides some setup information for debugging the Cortex®-M of STM32MP15xx microprocessors in Production Mode. Complete information is available in the chapter 4 of STM32CubeIDE user guide (UM2609).

In this mode, the available console on the board (UART4) is used by the 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

To make a test, modify file main.c from a generated project with a looping variable 'i', as depicted below.

Trace clock from the Linux® console



Then, setup the debug configuration, enabling SWV and setting the clock: 133.25 MHz in the example below.

Debug configuration with SWV enabled



Stop the debug session and open Serial Wire Views: Window > Show View > Other... > SWV > SWV Trace Log & SWV Data Trace.
In the SWV Trace Log > Configure Trace menu, set up Comparator 0 in order to spy variable 'i'.

SWVConfigureTraceButton.png


SWV setting

Then start the trace.

SWVStartTraceButton.png

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

SWV data trace output