Peripherals containing a DMA master can be configured so the security attribute of the DMA transfers is different from the security attribute of the peripheral itself. This allows a secure peripheral to do non-secure data transfers to or from the system memories.
The following conditions must be met:
- The DMA field of PERIPHID[n].PERM.SECURITYMAPPING should read as "SeparateAttribute"
- The peripheral itself should be secure (PERIPHID[n].PERM.SECATTR == 1)
Then it is possible to select the security attribute of the DMA transfers using the field DMASEC (PERIPHID[n].PERM.DMASEC == Secure and PERIPHID[n].PERM.DMASEC == NonSecure) in PERIPHID[n].PERM.