Datasheet
2015 Microchip Technology Inc. Preliminary DS60001320B-page 421
PIC32MZ Embedded Connectivity with Floating Point Unit (EF) Family
Figure 26-10 shows the Security Association control
word structure.
The Crypto Engine fetches different structures for dif-
ferent flows and ensures that hardware fetches mini-
mum words from SA required for processing. The
structure is ready for hardware optimal data fetches.
FIGURE 26-10: FORMAT OF SA_CTRL
Bit
Range
Bit
31/23/15/7
Bit
30/22/14/6
Bit
29/21/13/5
Bit
28/20/12/4
Bit
27/19/11/3
Bit
26/18/10/2
Bit
25/17/9/1
Bit
24/16/8/0
31-24 — —VERIFY— NO_RX OR_EN ICVONLY IRFLAG
23-16 LNC LOADIV FB FLAGS — — — ALGO<6>
15-8 ALGO<5:0> ENC
KEY
SIZE<1>
7-0
KEY
SIZE<0>
MULTITASK<2:0> CRYPTOALGO<3:0>
bit 31-30 Reserved: Do not use
bit 29 VERIFY: NIST Procedure Verification Setting
1 = NIST procedures are to be used
0 = Do not use NIST procedures
bit 28 Reserved: Do not use
bit 27 NO_RX: Receive DMA Control Setting
1 = Only calculate ICV for authentication calculations
0 = Normal processing
bit 26 OR_EN: OR Register Bits Enable Setting
1 = OR the register bits with the internal value of the CSR register
0 = Normal processing
bit 25 ICVONLY: Incomplete Check Value Only Flag
This affects the SHA-1 algorithm only. It has no effect on the AES algorithm.
1 = Only three words of the HMAC result are available
0 = All results from the HMAC result are available
bit 24 IRFLAG: Immediate Result of Hash Setting
This bit is set when the immediate result for hashing is requested.
1 = Save the immediate result for hashing
0 = Do not save the immediate result
bit 23 LNC: Load New Keys Setting
1 = Load a new set of keys for encryption and authentication
0 = Do not load new keys
bit 22 LOADIV: Load IV Setting
1 = Load the IV from this Security Association
0 = Use the next IV
bit 21 FB: First Block Setting
This bit indicates that this is the first block of data to feed the IV value.
1 = Indicates this is the first block of data
0 = Indicates this is not the first block of data
bit 20 FLAGS: Incoming/Outgoing Flow Setting
1 = Security Association is associated with an outgoing flow
0 = Security Association is associated with an incoming flow
bit 19-17 Reserved: Do not use