Re: [PATCH net-next v5 4/4] phy: aquantia: Determine rate adaptation support from registers

From: Vladimir Oltean
Date: Thu Jan 05 2023 - 12:55:54 EST


On Thu, Jan 05, 2023 at 07:52:06PM +0200, Vladimir Oltean wrote:
> On Thu, Jan 05, 2023 at 12:43:47PM -0500, Sean Anderson wrote:
> > Again, this is to comply with the existing API assumptions. The current
> > code is buggy. Of course, another way around this is to modify the API.
> > I have chosen this route because I don't have a situation like you
> > described. But if support for that is important to you, I encourage you
> > to refactor things.
>
> I don't think I'm aware of a practical situation like that either.
> I remember seeing some S32G boards with Aquantia PHYs which use 2500BASE-X
> for 2.5G and SGMII for <=1G, but that's about it in terms of protocol switching.
> As for Layerscape boards, SERDES protocol switching is a very new concept there,
> so they're all going to be provisioned for PAUSE all the way down
> (or USXGMII, where that is available).
>
> I just pointed this out because it jumped out to me. I don't have
> something against this patch getting accepted as it is.

A real-life (albeit niche) scenario where someone might have an Aquantia
firmware provisioned like this would be a 10G capable port that also
wants to support half duplex at 10/100 speeds. Although I'm not quite
sure who cares about half duplex all that much these days.