bng_en: add link management and statistics support

Hi,

This series enhances the bng_en driver by adding:
1. Link/PHY support
   a. Link query
   b. Async Link events
   c. Ethtool link set/get functionality
2. Hardware statistics reporting via ethtool -S

This version incorporates feedback received prior to splitting the
original series into two parts. 

 Addressed following comments from Andrew Lunn
   - Apply Rev-xmas fix in several places.
   - Correct ethtool-speed comment to reflect accurate behavior.
   https://lore.kernel.org/netdev/49930724-74b8-41fe-8f5c-48...
   https://lore.kernel.org/netdev/CANXQDtb5XuLKOOorCMYDUpVz6...

 Addressed following comments from Jakub Kicinski
   - Took care of missing mutex_init()
   https://lore.kernel.org/netdev/20251127190855.69779791@ke...
   https://lore.kernel.org/netdev/CANXQDtYy2JziaaVi=Cqt+gAJN...

 Addressed following comments from ALOK TIWARI
   - Add newline for clarity/formatting.
   https://lore.kernel.org/netdev/CANXQDtZbLhdwEtN+kKg1OVLV+...

v8:
 - Fix the smatch warnings reported by Dan Carpenter
    https://lore.kernel.org/r/202603180509.nOQGZrG0-lkp@intel...
v7:
 - Addressed the two valid issues reported by AI (Jakub Kicinski).
 - Fixed minor issues reported by Alok Tiwari.
 - Addressed the concern of statistics duplication raised by Jakub
   Kicinski. A few statistics (discards/errors) have been made part 
   of the standard netdev statistics and removed from ethtool -S.
   Additionally, a few statistics that require proper implementation
   have been removed and will be addressed in a later series, for example,
   get_pause_stats and get_fec_stats.
   https://lore.kernel.org/netdev/20260312192251.61243873@ke...

v6:
 - Resending the full series due to an SMTP failure during v5
   submission.
 - No functional changes from v5.

v5:
 Address Jakub Kicinski's comments by holding the instance lock across
 the entire service task (instead of flag-based locking) and checking
 the OPEN bit under the lock to resolve the close-path deadlock. 

v4:
 Addressed comments from Jakub Kicinski:
  - Explicitly size speed mask arrays to remove the need for manual
    sentinels in the hardware configuration.
  - Fix an off-by-one error in the queue index bound check.
  - Standardize ethtool -S per-ring stat naming to "rxq$id_$name"
    (e.g., rxq0_errors). Removed spaces and brackets to ensure
    compatibility with parsing scripts.
  - Exclude ethtool -S global counters (tx_err, tx_fifo_underruns,
    tx_total_collisions) already covered by rtnl_link_stats64.

v3:
 Addressed comments from Andrew Lunn:
  - Fix a comment and refactor bnge_hwrm_set_pause() 
    to improve code readability.

 Addressed comments from Jakub Kicinski:
  - Switch to RCU for stats synchronization and drop the 
    BNGE_STATE_READ_STATS state bit.

 Fix checkpatch warning by switching to kzalloc_node(). 

v2:
 Addressed comments from Andrew Lunn:
  - Add implementation for .get_pauseparam and .set_pauseparam to
    support
    a full flow control configuration, covering global autoneg,
independent
    pause autoneg, and forced RX/TX pause functionality.
  - Move MAC, PHY, Control, Pause, and RMON statistics from
    .get_ethtool_stats to their respective structured ethtool
    callbacks (e.g., .get_eth_mac_stats, .get_rmon_stats).
 
 Addressed comments from Jakub Kicinski:
  - Fix potential out-of-bounds read in speed mask array by adding 
    the missing sentinel.
  - Simplify timer synchronization by removing the redundant intr_sem.
  - Replace link_lock with the netdev instance lock, as it is sufficient
    to handle the required synchronization.

v1:
https://lore.kernel.org/all/20260223163641.755200-1-bharg...


Bhargava Marreddy (10):
  bng_en: add per-PF workqueue, timer, and slow-path task
  bng_en: query PHY capabilities and report link status
  bng_en: add ethtool link settings, get_link, and nway_reset
  bng_en: implement ethtool pauseparam operations
  bng_en: add support for link async events
  bng_en: add HW stats infra and structured ethtool ops
  bng_en: periodically fetch and accumulate hardware statistics
  bng_en: implement ndo_get_stats64
  bng_en: implement netdev_stat_ops
  bng_en: add support for ethtool -S stats display

 drivers/net/ethernet/broadcom/bnge/Makefile   |    3 +-
 drivers/net/ethernet/broadcom/bnge/bnge.h     |   12 +
 .../net/ethernet/broadcom/bnge/bnge_core.c    |    1 +
 .../net/ethernet/broadcom/bnge/bnge_ethtool.c |  723 +++++++++
 .../ethernet/broadcom/bnge/bnge_hwrm_lib.c    |  386 ++++-
 .../ethernet/broadcom/bnge/bnge_hwrm_lib.h    |    8 +
 .../net/ethernet/broadcom/bnge/bnge_link.c    | 1303 +++++++++++++++++
 .../net/ethernet/broadcom/bnge/bnge_link.h    |  204 +++
 .../net/ethernet/broadcom/bnge/bnge_netdev.c  |  597 +++++++-
 .../net/ethernet/broadcom/bnge/bnge_netdev.h  |   87 +-
 .../net/ethernet/broadcom/bnge/bnge_txrx.c    |   35 +-
 11 files changed, 3340 insertions(+), 19 deletions(-)
 create mode 100644 drivers/net/ethernet/broadcom/bnge/bnge_link.c
 create mode 100644 drivers/net/ethernet/broadcom/bnge/bnge_link.h

-- 
2.47.1