[PATCH net-next V2 2/2] net: axienet: Add support for 2500base-X only configuration.

[Andrew Lunn]

On Wed, Mar 12, 2025 at 03:06:32PM +0000, Gupta, Suraj wrote:
> [AMD Official Use Only - AMD Internal Distribution Only]
> 
> > -----Original Message-----
> > From: Andrew Lunn <andrew at lunn.ch>
> > Sent: Wednesday, March 12, 2025 8:29 PM
> > To: Gupta, Suraj <Suraj.Gupta2 at amd.com>
> > Cc: Russell King <linux at armlinux.org.uk>; Pandey, Radhey Shyam
> > <radhey.shyam.pandey at amd.com>; andrew+netdev at lunn.ch;
> > davem at davemloft.net; edumazet at google.com; kuba at kernel.org;
> > pabeni at redhat.com; robh at kernel.org; krzk+dt at kernel.org; conor+dt at kernel.org;
> > Simek, Michal <michal.simek at amd.com>; netdev at vger.kernel.org;
> > devicetree at vger.kernel.org; linux-kernel at vger.kernel.org; linux-arm-
> > kernel at lists.infradead.org; git (AMD-Xilinx) <git at amd.com>; Katakam, Harini
> > <harini.katakam at amd.com>
> > Subject: Re: [PATCH net-next V2 2/2] net: axienet: Add support for 2500base-X only
> > configuration.
> >
> > Caution: This message originated from an External Source. Use proper caution
> > when opening attachments, clicking links, or responding.
> >
> >
> > > > On Wed, Mar 12, 2025 at 02:25:27PM +0100, Andrew Lunn wrote:
> > > > > > +   /* AXI 1G/2.5G ethernet IP has following synthesis options:
> > > > > > +    * 1) SGMII/1000base-X only.
> > > > > > +    * 2) 2500base-X only.
> > > > > > +    * 3) Dynamically switching between (1) and (2), and is not
> > > > > > +    * implemented in driver.
> > > > > > +    */
> >
> > > - Keeping previous discussion short, identification of (3) depends on
> > > how user implements switching logic in FPGA (external GT or RTL
> > > logic). AXI 1G/2.5G IP provides only static speed selections and there
> > > is no standard register to communicate that to software.
> >
> > So if anybody has synthesised it as 3) this change will break their system?
> >
> >         Andrew
> 
> It will just restrict their system to (2)

Where as before, it was doing SGMII/1000base-X only. So such systems
break?

	Andrew