I am using K81 / K82 MCUs and got the USB CCID interface working. If I move the USB descriptors to flash area, then USB enumeration fails. I have tried the following but it doesn't work.
/* Disable MPU. All accesses from all bus masters are allowed now. */
MPU_CESR = (0);
// Set read access for USB master #3
FMC_PFAPR |= FMC_PFAPR_M3AP(01); // USB is master #3
// USB master 3 is trusted for read access
AIPS0_MPRA |= AIPS_MPRA_MTR3(1);
Is there anything I am missing?