bxe: Add 2.5G SGMII support (SFP GPON ONT)

[olivier]

Summary

This is an old well-known patch (from 2018) originating from here:
https://www.dslreports.com/forum/r32230041-Internet-Bypassing-the-HH3K-up-to-2-5Gbps-using-a-BCM57810S-NIC

So this patch was adapted to the current head from the patch posted here:
https://www.dslreports.com/forum/r32230853-

It allows to reach 2.5Gbps with GPON SFP on QLogic NetXtreme II BCM57810.

This patch is used by lot of pfSense/OPNSense and FreeBSD user on their home router.
This will ease life of all home fiber users.

[jlduran]

sys/dev/bxe/bxe.c

13812

bxe_mask_tx_fault > 1?

[luca.piccirillo_gmail.com]

sys/dev/bxe/bxe.c

13812

•0 (default) tx fault detection
•1 disable tx fault detection on port 1
•2 disable tx fault detection on port 2
•3 disable tx fault detection on ports 1 and 2

sys/dev/bxe/bxe_elink.c

10178

I cannot understand this bitmask conditions. It looks to me that you are enforcing 1G capability to be enabled in cap_mask even for 2_5G. Why?