Re: Unsupported phy-connection-type sgmii-2500 in arch/powerpc/boot/dts/fsl/t1023rdb.dts

["Pali Rohár" <pali@kernel.org>]

On Thursday 03 June 2021 17:12:31 Andrew Lunn wrote:
> On Thu, Jun 03, 2021 at 04:34:53PM +0200, Pali Rohár wrote:
> > Hello!
> > 
> > In commit 84e0f1c13806 ("powerpc/mpc85xx: Add MDIO bus muxing support to
> > the board device tree(s)") was added following DT property into DT node:
> > arch/powerpc/boot/dts/fsl/t1023rdb.dts fm1mac3: ethernet@e4000
> > 
> >     phy-connection-type = "sgmii-2500";
> > 
> > But currently kernel does not recognize this "sgmii-2500" phy mode. See
> > file include/linux/phy.h. In my opinion it should be "2500base-x" as
> > this is mode which operates at 2.5 Gbps.
> > 
> > I do not think that sgmii-2500 mode exist at all (correct me if I'm
> > wrong).
> 
> Kind of exist, unofficially. Some vendors run SGMII over clocked at
> 2500. But there is no standard for it, and it is unclear how inband
> signalling should work. Whenever i see code saying 2.5G SGMII, i
> always ask, are you sure, is it really 2500BaseX? Mostly it gets
> changed to 2500BaseX after review.

So this is question for authors of that commit 84e0f1c13806. But it
looks like I cannot send them emails because of following error:

<Minghuan.Lian@freescale.com>: connect to freescale.com[192.88.156.33]:25: Connection timed out

Do you have other way how to contact maintainers of that DTS file?
arch/powerpc/boot/dts/fsl/t1023rdb.dts

> PHY mode sgmii-2500 does not exist in mainline.

Yes, this is reason why I sent this email. In DTS is specified this mode
which does not exist.

> 	Andrew
>