9.15. PTP hardware clock register block

The PTP hardware clock register block has a header with type 0x0000C080, version 0x00000100, and carries several control registers for the PTP clock.

Address

Field

31..24

23..16

15..8

7..0

Reset value

RBB+0x00

Type

Vendor ID

Type

RO 0x0000C080

RBB+0x04

Version

Major

Minor

Patch

Meta

RO 0x00000100

RBB+0x08

Next pointer

Pointer to next register block

RO -

RBB+0x0C

Control

Control

RO -

RBB+0x10

Current time

Current time (fractional ns)

RO -

RBB+0x14

Current time

Current time (ns)

RO -

RBB+0x18

Current time

Current time (sec, lower 32)

RO -

RBB+0x1C

Current time

Current time (sec, upper 32)

RO -

RBB+0x20

Get time

Get time (fractional ns)

RO -

RBB+0x24

Get time

Get time (ns)

RO -

RBB+0x28

Get time

Get time (sec, lower 32)

RO -

RBB+0x2C

Get time

Get time (sec, upper 32)

RO -

RBB+0x30

Set time

Set time (fractional ns)

RW -

RBB+0x34

Set time

Set time (ns)

RW -

RBB+0x38

Set time

Set time (sec, lower 32)

RW -

RBB+0x3C

Set time

Set time (sec, upper 32)

RW -

RBB+0x40

Period

Period (fractional ns)

RW -

RBB+0x44

Period

Period (ns)

RW -

RBB+0x48

Nominal period

Nominal period (fractional ns)

RO -

RBB+0x4C

Nominal period

Nominal period (ns)

RO -

RBB+0x50

Adj time

Adj time (fractional ns)

RW -

RBB+0x54

Adj time

Adj time (ns)

RW -

RBB+0x58

Adj time count

Adj time cycle count

RW -

RBB+0x5C

Adj time act

Adj time active

RO -

See Register blocks for definitions of the standard register block header fields.

Current time

The current time registers read the current time from the PTP clock, with no double-buffering.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x10

Current time (fractional ns)

RO -

RBB+0x14

Current time (ns)

RO -

RBB+0x18

Current time (sec, lower 32)

RO -

RBB+0x1C

Current time (sec, upper 32)

RO -

Get time

The get time registers read the current time from the PTP clock, with all values latched coincident with reading the fractional ns register.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x20

Get time (fractional ns)

RO -

RBB+0x24

Get time (ns)

RO -

RBB+0x28

Get time (sec, lower 32)

RO -

RBB+0x2C

Get time (sec, upper 32)

RO -

Set time

The set time registers set the current time on the PTP clock, with all values latched coincident with writing the upper 32 bits of the seconds field.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x30

Set time (fractional ns)

RW -

RBB+0x34

Set time (ns)

RW -

RBB+0x38

Set time (sec, lower 32)

RW -

RBB+0x3C

Set time (sec, upper 32)

RW -

Period

The period registers control the period of the PTP clock, with all values latched coincident with writing the ns field. The period value is accumulated into the PTP clock on every clock cycle.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x40

Period (fractional ns)

RW -

RBB+0x44

Period (ns)

RW -

Nominal period

The nominal period registers contain the nominal period of the PTP clock, which corresponds to zero frequency offset in the ideal case.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x48

Nominal period (fractional ns)

RO -

RBB+0x4C

Nominal period (ns)

RO -

Adjust time

The adjust time registers can be used to slew the clock over some time period. An adjustment can be specified with some amount of time added every clock cycle for N cycles.

Address

31..24

23..16

15..8

7..0

Reset value

RBB+0x50

Adj time (fractional ns)

RW -

RBB+0x54

Adj time (ns)

RW -

RBB+0x58

Adj time cycle count

RW -

RBB+0x5C

Adj time active

RO -