The code on Musca-S1 is running from on-chip eMRAM (2MB non-volatile bootable memory). Make sure that the DAPLink FW for QSPI/MRAM is downloaded to the board. You can find on the Arm Community page A short description of how to update the DAPLink FW can be found there as well.
This service is designed to perform secure pin services of the platform (e.g alternate function setting, pin mode setting, etc). The service uses the IOCTL API of TF-M's Platform Service, which allows the non-secure application to make pin service requests on Musca S1 based on a generic service request delivery mechanism.
Copyright (c) 2023, Arm Limited. All rights reserved.