[Intel-wired-lan] [net-next PATCH 0/7] intel: ptp: convert .adjfreq to .adjfine

[Jacob Keller <jacob.e.keller@intel.com>]

Convert all of the Intel drivers with PTP support to the newer .adjfine
implementation which uses scaled parts per million.

This improves the precision of the frequency adjustments by taking advantage
of the full scaled parts per million input coming from user space.

In addition, all implementations are converted to using the
mul_u64_u64_div_u64 function which better handles the intermediate value.
This function supports architecture specific instructions where possible to
avoid loss of precision if the normal 64-bit multiplication would overflow.

Of note, the i40e implementation is now able to avoid loss of precision on
slower link speeds by taking advantage of this to multiply by the link speed
factor first. This results in a significantly more precise adjustment by
allowing the calculation to impact the lower bits.

This also gets us a step closer to being able to remove the .adjfreq
entirely by removing its use from many drivers.

I plan to follow this up with a series to update the drivers from other
vendors and drop the .adjfreq implementation entirely.

Jacob Keller (7):
  ice: implement adjfine with mul_u64_u64_div_u64
  e1000e: remove unnecessary range check in e1000e_phc_adjfreq
  e1000e: convert .adjfreq to .adjfine
  i40e: use mul_u64_u64_div_u64 for PTP frequency calculation
  i40e: convert .adjfreq to .adjfine
  ixgbe: convert .adjfreq to .adjfine
  igb: convert .adjfreq to .adjfine

 drivers/net/ethernet/intel/e1000e/e1000.h    |  2 +-
 drivers/net/ethernet/intel/e1000e/netdev.c   |  4 +-
 drivers/net/ethernet/intel/e1000e/ptp.c      | 18 +++--
 drivers/net/ethernet/intel/i40e/i40e_ptp.c   | 35 ++++------
 drivers/net/ethernet/intel/ice/ice_ptp.c     | 16 +----
 drivers/net/ethernet/intel/igb/igb_ptp.c     | 15 ++--
 drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c | 73 +++++++++++---------
 7 files changed, 75 insertions(+), 88 deletions(-)


base-commit: 9f055d4106bdefd5a533316c1d3dc3b5e9821b9a
-- 
2.35.1.456.ga9c7032d4631

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