Re: [PATCH net v2] net: phy: intel-xway: workaround 100BASE-TX Link-Up issue

[Andrew Lunn]

On Tue, Sep 22, 2026 at 09:52:46AM +0200, A. Sverdlin wrote:
> From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
> 
> MaxLinear GSW12x/GSW14x Ethernet Switch Errata Sheet states:
> "An issue has been sporadically observed after device power-on on the first
> link-up attempt in 100BASE-TX mode resulting in either the link-up taking a
> long time, or failing to link-up altogether...
> 
> Workaround:
> After power-on, enable Cable Diagnostic Mode for all ports and disable
> it..."
> 
> Implement the proposed workaround unconditionally in the Intel XWAY driver
> (MaxLinear GSW1xx switches incorporate Intel XWAY PHYs) because the
> diagnostic bits have the same meaning even in older integral PHYs such as
> GPY111/PEF7071/PHY11G. So it's not clear how to distinguish the affected
> newer integrated PHYs, but the workaround should not hurt the older PHYs.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 22335939ec90 ("net: dsa: add driver for MaxLinear GSW1xx switch family")
> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>

Reviewed-by: Andrew Lunn <andrew@xxxxxxx>

    Andrew