[PATCH net-next v2 2/3] net: ethernet: mediatek: Re-add support SGMII

Russell King - ARM Linux admin linux at armlinux.org.uk
Thu Aug 22 14:11:56 PDT 2019

Hi Rene,

On Thu, Aug 22, 2019 at 07:50:33PM +0000, René van Dorst wrote:
> Quoting Russell King - ARM Linux admin <linux at armlinux.org.uk>:
> > Isn't this set for Cisco SGMII as well as for 802.3 1000BASE-X and
> > the up-clocked 2500BASE-X modes?
> > 
> > If so, is there a reason why 10Mbps and 100Mbps speeds aren't
> > supported on Cisco SGMII links?
> I can only tell a bit about the mt7622 SOC, datasheet tells me that:
> The SGMII is the interface between 10/100/1000/2500 Mbps PHY and Ethernet MAC,
> the spec is raised by Cisco in 1999, which is aims for pin reduction compare
> with the GMII. It uses 2 differential data pair for TX and RX with clock
> embedded bit stream to convey frame data and port ability information.
> The core leverages the 1000Base-X PCS and Auto-Negotiation from IEEE 802.3
> specification (clause 36/37). This IP can support up to 3.125G baud for
> 2.5Gbps
> (proprietary 2500Base-X) data rate of MAC by overclocking.
> Also features tells me: Support 10/100/1000/2500 Mbps in full duplex mode and
> 10/100 Mbps in half duplex mode.

Yep, that is what I'd expect.  Thanks.

RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

More information about the Linux-mediatek mailing list