ENC=B_0x0, CTXID=B_0x0, BREN=B_0x0
MCE region 4 configuration register
| BREN | Base region enable 0 (B_0x0): Region x is disabled. Access control of primary region (privileged or unprivileged, no encryption) applies to any access between this region start and end addresses. 1 (B_0x1): Region x is enable. Access controls and encryption option defined in this region apply to any access between this region start and end addresses. |
| CTXID | Context ID 0 (B_0x0): If ENC=10 (resp. 11) the key stored in MCE_MKEYR (resp. MCE_FMKEYR) registers is used by the block cipher. If ENC=01 bypass mode is selected instead of stream cipher. 1 (B_0x1): If ENC=10 or 11 the key stored in MCE_CC1KEYR is used by the block cipher. 2 (B_0x2): If ENC=10 or 11 the key stored in MCE_CC2KEYR is used by the block cipher. |
| ENC | Encrypted region 0 (B_0x0): No effects 1 (B_0x1): Stream cipher - All allowed read (resp. write) requests are decrypted (resp. encrypted) using the stream cipher, when CCEN bit is set in MCE_CCzCFGR (where CTXID=z). 2 (B_0x2): Block cipher - All allowed read (resp. write) requests are decrypted (resp. encrypted) using the SCA resistant block cipher. If CTXID=0 and MKVALID=0 bypass mode is selected instead. If CTXID=z and CCEN bit is cleared in MCE_CCzCFGR bypass mode is also selected. 3 (B_0x3): Fast block cipher - All allowed read (resp. write) requests are decrypted (resp. encrypted) using the fast block cipher. If CTXID=0 and FMKVALID=0 bypass mode is selected instead. If CTXID=z and CCEN bit is cleared in MCE_CCzCFGR bypass mode is also selected. |