Altera 10-Gbps Ethernet MAC MegaCore Function - Manual (Page 92)

Chapter 7: Functional Description 7–25
IEEE 1588v2
February 2014 Altera Corporation 10-Gbps Ethernet MAC MegaCore Function User Guide
7.9.3. Receive Datapath
In the receive datapath, the IEEE 1588v2 feature provides a timestamp for all receive
frames. The timestamp is aligned with the avalon_st_rx_startofpacket signal.
7.9.4. Frame Format
The MAC function, with the IEEE 1588v2 feature, supports PTP packet transfer for the
following transport protocols:
■ IEEE 802.3
■ UDP/IPv4
■ UDP/IPv6
7.9.4.1. PTP Packet in IEEE 802.3
Figure 7–14 shows the format of the PTP packet encapsulated in IEEE 802.3.
Figure 7–14. PTP Packet in IEEE 8002.3
Note to Figure 7–14 :
(1) For packets with VLAN or Stacked VLAN tag, add 4 or 8 octets offsets before the length/type field.
flagField
correctionField
transportSpecific | messageType
reserved | versionPTP
reserved
1 Octet
1 Octet
1 Octet
2 Octets
8 Octets
reserved 4 Octets
SourcePortIdentify 10 Octets
sequenceId 2 Octets
controlField 1 Octet
logMessageInterval 1 Octet
TimeStamp
Payload
10 Octets
domainNumber
messageLength 2 Octets
1 Octet
Length/Type = 0x88F7
Source Address
Destination Address
2 Octets
6 Octets
6 Octets
MAC Header
PTP Header
0..1500/9600 Octets
CRC 4 Octets
(1)