Re: [PATCH net v3] net: phylink: treat PSGMII as an inband capable interface

[Sandeep Sondagar]

Hi Nicolai,

Thanks for your email.

This was noticed while working on the OpenWrt support for the Jio
AirFiber router (JIDU6J11) based on the IPQ9554 SoC, which exposes
5x gigabit ports (1 WAN + 4 LAN) through a Qualcomm PSGMII interface.

While testing I found that the QSGMII mode works correctly, but the
PSGMII mode has both a hotplug issue and an incorrect link detection
issue: a 100Mbps copper link is reported as 1Gbps, so the link can't
pass traffic at the negotiated speed. While tracing it, I found
PHY_INTERFACE_MODE_PSGMII was missing from the phylink in-band
handling, so the PCS was being programmed in force mode with its
default 1000base control-register speed bits instead of using the
in-band SGMII word.

Best regards,
Sandeep