Non-secure configuration of UART1 on Arm Musca-A1


I'm using Arm Musca-A1 and I am stuck with the configuration of UART1 to non-secure. From my understanding, to configure the peripheral to a non-secure access setting one should configure SAU and give access to it in the 

Secure Privilege Control component (AHBNSPPCEXP0); however, after transitioning to the NS world, on the first attempt to access UART1 registers (e.g. UART1IBRD) I got an hardfault with the following status in the CFSR, HFSR and SFSR. 
Is anything that I missing? 
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