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 (registration required) various documents highlighting:

System Workbench for STM32

You are viewing a reply to stm32L4-Discovery and cubemx ?  

stm32L4-Discovery and cubemx ?

Run the ST-Link Utility and verify that the target communication mode is set to “Connect Under Reset”. My understanding is that if this option is not set for a L family device then the ST-Link can’t communicate with the target device.