Hardware/AES engine

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The Hollywood's AES Engine encrypts/decrypts 16-byte blocks using AES-128 in Cipher Block Chaining mode.

AES engine
Access
BroadwayNone
StarletFull
Registers
Base0x0d020000
Length0x14
Access size32 bits
Byte orderBig Endian
IRQs
Hollywood2
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Register List

NAND Interface
Address Bits Name Description
0x0d020000 32 AES_CTRL AES Control and Status
0x0d020004 32 AES_SRC Source memory address
0x0d020008 32 AES_DEST Destination memory address
0x0d02000c 32 AES_KEY Key FIFO
0x0d020010 32 AES_IV IV FIFO

Register Details

AES_CTRL (0x0d020000)
  31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Access R/W R/W R? R/W R/W U
Field EXEC IRQ ERR CMD MODE
  15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Access U W W
Field IV BLOCKS

This register controls the state of the AES engine.

Field Description
EXEC Write 1: initiate AES command
Read: AES engine busy
IRQ Set to enable IRQ generation when command is complete
ERR If set, AES error occured (?)[check]
ENA Enable en/decryption. If clear, the data is copied straight from source to destination without change (useful as a DMA copy engine?).
MODE 0 for encrypt, 1 for decrypt.
IV If set, use the supplied IV. If clear, chain from last command (continue CBC mode).
DATALEN Number of 16-byte blocks to process, minus one. 0 means one block.

AES_SRC (0x0d020004)
  310
Access R/W

This register contains the DMA address of the source data. The same buffer can be used for source and destination. The bottom 4 bits are ignored (must be 16-byte aligned).


AES_SRC (0x0d020008)
  310
Access R/W

This register contains the DMA address of the destination data. The same buffer can be used for source and destination. The bottom 4 bits are ignored (must be 16-byte aligned).


AES_KEY (0x0d02000c)
  310
Access W

This register implements a FIFO that accepts the AES key. A sequence of four 32-bit writes will set the AES key (starting with the leftmost 32-bit word).


AES_KEY (0x0d02000c)
  310
Access W

This register implements a FIFO that accepts the AES IV. A sequence of four 32-bit writes will set the AES IV (starting with the leftmost 32-bit word). Set the IV bit in the AES_CTRL register to restart the CBC encryption using this IV instead of using the last encrypted block.