Freescale Semiconductor MCF5480 - Manual (Page 636)

MCF548x Reference Manual, Rev. 3
22-34 Freescale Semiconductor
22.9 Data Encryption Standard Execution Units (DEU)
This section contains details about the Data Encryption Standard Execution Units (DEU), including
detailed register map, modes of operation, status and control registers, and FIFOs.
22.9.1 DEU Register Map
The registers used in the DEU are documented primarily for debug and target mode operations. If the SEC
requires the use of the DEU when acting as an initiator, accessing these registers directly is unnecessary.
The device drivers and the on-chip controller will abstract register level access from the user. The DEU
contains the following registers:
• Reset control register
• Status register
• Interrupt status register
• Interrupt mask register
22.9.2 DEU Reset Control Register (DRCR)
This register, shown in Figure 22-25 , allows 3 levels reset of just DEU, as defined by three self-clearing
bits.
19 ERE Early Read Error. The AFEU register was read while the AFEU was performing encryption.
0 Early read error enabled
1 Early read error disabled
18 CE Context Error. An AFEU key register, the key size register, data size register, mode register,
or context memory was modified while AFEU was performing encryption.
0 Context error enabled
1 Context error disabled
17 KSE Key Size Error. A value outside the bounds 1–16 bytes was written to the AFEU key size
register
0 Key size error enabled
1 Key size error disabled
16 DSE Data Size Error. An inconsistent value was written to the AFEU data size register:
0 Data Size error enabled
1 Data size error disabled
15–0 — Reserved, should be cleared.
Table 22-21. AFIMR Field Descriptions (Continued)
Bits Names Description