Merge branch 'net-thunderx-add-support-for-PTP-clock'

Aleksey Makarov says:

====================
net: thunderx: add support for PTP clock

This series adds support for IEEE 1588 Precision Time Protocol
to Cavium ethernet driver.

The first patch adds support for the Precision Time Protocol Clocks and
Timestamping coprocessor (PTP) found on Cavium processors.
It registers a new PTP clock in the PTP core and provides functions
to use the counter in BGX, TNS, GTI, and NIC blocks.

The second patch introduces support for the PTP protocol to the
Cavium ThunderX ethernet driver.

v6:
- check if ptp_clock_register() returns NULL (Richard Cochran)
- fix doc comment for cavium_ptp_enable() (Richard Cochran)
- fix a function call formatting; use defined constant (Richard Cochran)
- add comments for `tx_ptp_skbs` and `ptp_skb` (Richard Cochran)
- use adjfine() instead of adjfreq() (Richard Cochran)
- add Acked-by: Philippe Ombredanne <pombredanne@nexb.com>

v5: https://lkml.kernel.org/r/20171211141435.2915-1-aleksey.makarov@cavium.com
- fix the file headers (add SPDX tags, remove advertisment) (Philippe Ombredanne)
- use "imply" instead of "select" (Richard Cochran)
- add some code in cavium_ptp_get() for the case when the PTP driver has not been
  registered with the PTP core

v4: https://lkml.kernel.org/r/20171208103442.19354-1-aleksey.makarov@cavium.com
- use IS_ENABLED. This fixes compilation of the ptp as a module (David Miller)
- select PTP_1588_CLOCK, not depend on it.  This fixes a build warning.
- change u64 to __be64.  This fixes the sparse warning
  "warning: cast to restricted __be64"
- make nicvf_config_hwtstamp() static. This fixes the sparse warning
  "warning: symbol 'nicvf_config_hwtstamp' was not declared. Should it be static?"

v3: https://lkml.kernel.org/r/20171206133100.26436-1-aleksey.makarov@cavium.com
- rebase to net-next

v2: https://lkml.kernel.org/r/20171117134909.8954-1-aleksey.makarov@cavium.com
- use readq()/writeq() in place of cavium_ptp_reg_read()/cavium_ptp_reg_write(),
  don't use readq_relaxed()/writeq_relaxed() (David Daney)

v1: https://lkml.kernel.org/r/20171107190704.15458-1-aleksey.makarov@cavium.com
====================

Signed-off-by: David S. Miller <davem@davemloft.net>