On 12/01/2026 9:03, Kenta Akagi wrote:

Hi,

I would like to measure the cable BER on ConnectX.

According to the documentation[1][2], there are counters that can be used
for this purpose: rx_corrected_bits_phy, rx_pcs_symbol_err_phy and
rx_bits_phy. However, rx_bits_phy does not show up in ethtool
statistics.

This patch exposes the PPCNT phy_received_bits as rx_bits_phy.


On a ConnectX-5 with 25Gbase connection, it works as expected.

On the other hand, although I have not verified it, in an 800Gbps
environment rx_bits_phy would likely overflow after about 124 days.
Since I cannot judge whether this is acceptable, I am posting this as an
RFC first.

Hi,

This is a 64-bits counter so no overflow is expected.

[1] commit 8ce3b586faa4 ("net/mlx5: Add counter information to mlx5
     driver documentation")
[2] https://docs.kernel.org/networking/device_drivers/ethernet/mellanox/mlx5/counters.html

Kenta Akagi (1):
   net/mlx5e: Expose physical received bits counters to ethtool

  drivers/net/ethernet/mellanox/mlx5/core/en_stats.c | 1 +
  1 file changed, 1 insertion(+)