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.
If the following conditions are met:
- The DMA field of PERIPH[n].PERM.DMA is "SeparateAttribute"
- The peripheral itself is secure (PERIPH[n].PERM.SECATTR == 1)
Then it is possible to select the security attribute of the DMA transfers using the field DMASEC (PERIPH[n].PERM.DMASEC == Secure and PERIPH[n].PERM.DMASEC == NonSecure) in PERIPH[n].PERM.