Visible to Intel only — GUID: jyo1613127021409
Ixiasoft
Visible to Intel only — GUID: jyo1613127021409
Ixiasoft
7.15.3. TX 1-Step Timestamp Interface
The figure below shows how the PTP 1-step interface writes a 1-step timestamp to a PTP header. The timestamp signals are valid when i_tx_valid and i_tx_startofpacket signals are high. To initiate a timestamp request, the i_ptp_ins_ets signal must be high.
- In above diagram, first byte of timestamp field is 48th byte, the byte offset (i_ptp_tx_offset) is 47.
- The timestamp must not overwrite other fields such as headers or packet CRCs.
Signal Name |
Width | Description |
---|---|---|
i_ptp_ins_ets i_ptp_ins_ets[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Insert an egress timestamp signal for the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_ins_cf i_ptp_ins_cf[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Update the correction field with residence time in the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_zero_csum i_ptp_zero_csum[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Overwrites the UDP checksum with zeros in the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_update_eb i_ptp_update_eb[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Update the extended bytes field to cancel out checksum changes in the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE. When asserted, overwrites the extended bytes field in an IPv6 packet carried inside the current TX packet with a value that cancels out changes to the checksum due to changes to the UDP packet.
|
i_ptp_p2p i_ptp_p2p[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Add peer-to-peer mean path delay to correction field for the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_asym i_ptp_asym[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Add asymmetric latency to the correction field for the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_asym_sign i_ptp_asym_sign[1:0] |
1 bit (10GE/25GE,50GE/100GE/200GE) 2 bits (400GE) |
Sign of an asymmetry delay added to the correction field for the current TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_asym_p2p_idx[6:0] i_ptp_asym_p2p_idx[13:0] |
7 bits (10GE/25GE,50GE/100GE/200GE) 14 bits (400GE) |
Index of asymmetry delay and peer-to-peer mean path delay in the configurable lookup table 18 when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_ts_offset[15:0] i_ptp_ts_offset[31:0] |
16 bits (10GE/25GE,50GE/100GE/200GE) 32 bits (400GE) |
Presents the position of the PTP timestamp field in the TX packet when Ethernet rate is 10GE/25GE/50GE/100GE/200GE/400GE.
|
i_ptp_cf_offset[15:0] i_ptp_cf_offset[31:0] |
16 bits (10GE/25GE,50GE/100GE/200GE) 32 bits (400GE) |
Presents the position of the PTP correction field in the TX packet when Ethernet rate is 10GE/25GE,50GE/100GE/200GE/400GE.
|
i_ptp_csum_offset[15:0] i_ptp_csum_offset[31:0] |
16 bits (10GE/25GE,50GE/100GE/200GE) 32 bits (400GE) |
Position of the UDP checksum field in the TX packet when Ethernet rate is 10GE/25GE,50GE/100GE/200GE/400GE.
|
i_ptp_tx_its[95:0] i_ptp_tx_its[191:0] |
96 bits (10GE/25GE,50GE/100GE/200GE) 192 bits (400GE) |
Presents the ingress timestamp for the TX packet residence time calculation when Ethernet rate is 10GE/25GE,50GE/100GE/200GE/400GE. The timestamp represents time when packet arrives in the system. To generate the residence time, the TX packet compares this timestamp to the time when packet left the system.
|