Time Sync Registers
BCM5718 Programmer’s Guide
Broadcom
®
January 29, 2016 • 5718-PG108-R
Page 164
RX LOCK TIMER LSB REG [Offset 0x06C0]
RX LOCK TIMER MSB REG [Offset 0x06C4]
See
“RX PTP CONTROL REG [Offset 0X06C8]”
RX PTP CONTROL REG [Offset 0X06C8]
PTP Sequence ID
15:0 RO
0x0000
This field reflects the Sequence ID extracted from the
PTP packet which was last Time Stamped by RX
hardware
Note:
Hardware shall blindly capture 2 octets from
offset 30 of each time-stamped PTP packet – not all
message types carry SequenceId, so use this value
with discretion.
Name
Bits
Access Default Value Description
Lock Time LSB Value
31:0 RW
0x0000
See RX Lock Timer MSB Register.
Name
Bits
Access Default Value Description
Reserved
31:16 RO
0x0
Lock Time MSB Value
15:0 RW
0x00
This, concatenated with Lock Time LSB value,
constitutes a 48-bit Lock Timer value. Precision of
the value is 1ns – which equates to the precision of
the EAV Reference Count.
Name
Bits
Access Default Value Description
Reserved
31:28 RO
0x00
RX Time Stamp Interlock
Policy
27:26 RW
01
This field determines how the successive RX Time
Stamps are retained in the RX TIME STAMP
Register, given that there is a chance of over-write.
00 => HW freely over-writes RX Time Stamp values.
01 => Interlock Mode – HW does not over-write
unless SW reads a posted RX Time Stamp value.
10 => Lock Timer Mode – HW does not over-write
unless SW reads a posted RX Time Stamp value OR
the Lock Timer has expired.
11 => Reserved
Note:
Changing the state of this field while
receiving PTP traffic may result in abrupt HW
behavior. This field is best configured statically.
Name
Bits
Access Default Value Description