82583V Datasheet, PDF (153/374 Pages) Intel Corporation – Intel® 82583V GbE Controller

Inline Functions—82583V GbE Controller
7.2.10.4
Status - STA
The status field is written back to host memory in cases where the RS bit is set in the
command field. The DD bit indicates that the descriptor is done after the descriptor has
been processed.
3
2
1
0
Rsv
DD
Rsv (bit 3:1) - Reserved
DD (bit 0) - Descriptor done
7.2.10.5
Packet Options - POPTS
The POPTS field provides a number of options, which control the handling of this
packet. This field is relevant only on the first data descriptor of a packet or
segmentation context.
Note:
Note:
7
2
1
0
Rsv
TXSM
IXSM
Rsv (bits 7:2) - Reserved
TXSM (bit 1) - Insert TCP/UDP checksum
IXSM (bit 0) - Insert IP checksum
IXSM and TXSM are used to control insertion of the IP and TCP/UDP checksums,
respectively. If the corresponding bit is not set, whatever value software has placed
into the checksum field of the packet data is placed on the wire.
For proper values of the IP and TCP checksum, software must set the IXSM and TXSM
when using the transmit segmentation.
Software should not set this field for IPv6 packets.
7.2.10.6
VLAN
The VLAN field is used to provide the 802.1Q tagging information. The special field is
ignored if the VLE bit in the DCMD command byte is 0b.
15
13
12
11
0
PRI
CFI
VLAN ID
153