CHACHA_CONTROL

Address offset: 0x380

Control the CHACHA engine behavior.


Bit number				31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
ID																									G	F				E	E	D	C	B	A
Reset 0x00000000				0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
ID	R/W	Field	Value ID	Value								Description
A	RW	CHACHA_OR_SALSA										Run engine in ChaCha or Salsa mode
			ChaCha	0								Run engine in ChaCha mode
			Salsa	1								Run engine in Salsa mode
B	RW	INIT										Perform initialization for a new message
			Disable	0								Message already initialized
			Enable	1								Initialize new message
C	RW	GEN_KEY_POLY1305										Generate the key to use in Poly1305 message authentication code calculation.
			Disable	0								Do not generate Poly1305 key
			Enable	1								Generate Poly1305 key
D	RW	KEY_LEN										Key length selection.
			256Bits	0								Use 256 bits key length
			128Bits	1								Use 128 bits key length
E	RW	NUM_OF_ROUNDS										Set number of permutation rounds, default value is 20.
			Default	0								Use 20 rounds of rotation (default)
			12Rounds	1								Use 12 rounds of rotation
			8Rounds	2								Use 8 rounds of rotation
F	RW	RESET_BLOCK_CNT										Reset block counter for new messages
			Disable	0								Use current block counter value
			Enable	1								Reset block counter value to zero
G	RW	USE_IV_96BIT										Use 96 bits Initialization Vector (IV)
			Disable	0								Use default size IV of 64 bit
			Enable	1								The IV is 96 bits