SW4STM32 and SW4Linux fully supports the STM32MP1 asymmetric multicore Cortex/A7+M4 MPUs

   With System Workbench for Linux, Embedded Linux on the STM32MP1 family of MPUs from ST was never as simple to build and maintain, even for newcomers in the Linux world.
And, if you install System Workbench for Linux in System Workbench for STM32 you can seamlessly develop and debug asymmetric applications running partly on Linux, partly on the Cortex-M4.
You can get more information from the ac6-tools website and download two short videos (registration required) highlighting:

System Workbench for STM32

Single Step Debugging while a timer is active


Please find below an extract from openocd documentation >> 16.5.5 Cortex-M specific commandsQuestion

Command: cortex_m maskisr (auto|on|off)

Control masking (disabling) interrupts during target step/resume.

The auto option handles interrupts during stepping a way they get served but don’t disturb the program flow. The step command first allows pending interrupt handlers to execute, then disables interrupts and steps over the next instruction where the core was halted. After the step interrupts are enabled again. If the interrupt handlers don’t complete within 500ms, the step command leaves with the core running.

Note that a free breakpoint is required for the auto option. If no breakpoint is available at the time of the step, then the step is taken with interrupts enabled, i.e. the same way the off option does.

Default is auto.