SHA/MD5 Registers
1605
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
SHA/MD5 Accelerator
25.2.3 SHA_MODE Register (Offset = 0x44) [reset = 0x0]
SHA Mode (SHA_MODE)
This register is written to configure the hash algorithm to be used in the hash operation.
SHA_MODE is shown in
and described in
.
Return to
Figure 25-6. SHA_MODE Register
31
30
29
28
27
26
25
24
RESERVED
R-0x0
23
22
21
20
19
18
17
16
RESERVED
R-0x0
15
14
13
12
11
10
9
8
RESERVED
R-0x0
7
6
5
4
3
2
1
0
HMAC_OUTER
_HASH
RESERVED
HMAC_KEY_P
ROC
CLOSE_HASH
ALGO_CONST
ANT
ALGO
R/W-0x0
R-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x0
Table 25-17. SHA_MODE Register Field Descriptions
Bit
Field
Type
Reset
Description
31-8
RESERVED
R
0x0
7
HMAC_OUTER_HASH
R/W
0x0
HMAC Outer Hash Processing Enable.
This bit is written to indicate that the outer hash should be performed
on the hash digest when the inner hash has finished.
The inner hash finishes when the length of hash has been
processed the final inner hash is performed (if CLOSE_HASH was
set to 1).
This bit should normally be set together with CLOSE_HASH to finish
the inner hash first, or immediately when block length is zero (HMAC
continue with the just outer hash to be done).
This bit is auto-cleared when outer hash is finished.
0x0 = No operation
0x1 = Enable HMAC processing of outer hash.This bit self-clears
when outer hash is finished.
6
RESERVED
R
0x0
5
HMAC_KEY_PROC
R/W
0x0
HMAC Key Processing Enable.
This bit enables HMAC key processing on the
512-bit HMAC key loaded into the SHA_IDIGEST_A through
SHA_IDIGEST_H registers and the SHA_ODIGEST_A through
SHA_ODIGEST_H register block.
Once HMAC key processing is finished, this bit is automatically
cleared and the resulting Inner and Outer digest is available in the
SHA_IDIGEST_x and SHA_ODIGEST_x respectively.
After key processing is complete, regular hash processing begins
until the block length is exhausted.
0x0 = No operation
0x1 = Enable HMAC key processing. This bit is automatically cleared
once HMAC key processing is finished.