Datasheet

 2015 Microchip Technology Inc. Preliminary DS60001320B-page 415
PIC32MZ Embedded Connectivity with Floating Point Unit (EF) Family
FIGURE 26-2: FORMAT OF BD_CTRL
FIGURE 26-3: FORMAT OF BD_SADDR
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 DESC_EN
— CRY_MODE<2:0> — — —
23-16
—
SA_
FETCH_EN
— — LAST_BD LIFM
PKT_
INT_EN
CBD_
INT_EN
15-8
BD_BUFLEN<15:8>
7-0
BD_BUFLEN<7:0>
bit 31 DESC_EN: Descriptor Enable
1 = The descriptor is owned by hardware. After processing the BD, hardware resets this bit to ‘0’.
0 = The descriptor is owned by software
bit 30 Unimplemented: Must be written as ‘0’
bit 29-27 CRY_MODE<2:0>: Crypto Mode
111 = Reserved
110 = Reserved
101 = Reserved
100 = Reserved
011 = CEK operation
010 = KEK operation
001 = Preboot authentication
000 = Normal operation
bit 22 SA_FETCH_EN: Fetch Security Association From External Memory
1 = Fetch SA from the SA pointer. This bit needs to be set to ‘1’ for every new packet.
0 = Use current fetched SA or the internal SA
bit 21-20 Unimplemented: Must be written as ‘0’
bit 19 LAST_BD: Last Buffer Descriptors
1 = Last Buffer Descriptor in the chain
0 = More Buffer Descriptors in the chain
After the last BD, the CEBDADDR goes to the base address in CEBDPADDR.
bit 18 LIFM: Last In Frame
In case of Receive Packets (from H/W-> Host), this field is filled by the Hardware to indicate whether the
packet goes across multiple buffer descriptors. In case of transmit packets (from Host -> H/W), this field
indicates whether this BD is the last in the frame.
bit 17 PKT_INT_EN: Packet Interrupt Enable
Generate an interrupt after processing the current buffer descriptor, if it is the end of the packet.
bit 16 CBD_INT_EN: CBD Interrupt Enable
Generate an interrupt after processing the current buffer descriptor.
bit 15-0 BD_BUFLEN<15:0>: Buffer Descriptor Length
This field contains the length of the buffer and is updated with the actual length filled by the receiver.
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 BD_SAADDR<31:24>
23-16 BD_SAADDR<23:16>
15-8 BD_SAADDR<15:8>
7-0 BD_SAADDR<7:0>
bit 31-0 BD_SAADDR<31:0>: Security Association IP Session Address
The sessions’ SA pointer has the keys and IV values.