Re: [PATCH net-next 4/6] net: dsa: mt7530: Add the support of MT7531 switch

[Landen Chao]

Hi Andrew,

On Wed, 2019-12-11 at 00:35 +0800, Andrew Lunn wrote:
> On Tue, Dec 10, 2019 at 04:14:40PM +0800, Landen Chao wrote:
> > Add new support for MT7531:
> > 
> > MT7531 is the next generation of MT7530. It is also a 7-ports switch with
> > 5 giga embedded phys, 2 cpu ports, and the same MAC logic of MT7530. Cpu
> > port 6 only supports HSGMII interface. Cpu port 5 supports either RGMII
> > or HSGMII in different HW sku.
> 
> Hi Landen
> 
> Looking at the code, you seem to treat HSGMII as 2500Base-X. Is this
> correct? Or is it SGMII over clocked to 2.5Gbps?
After re-read MT7622 tread[0] again, and according to the configurable
part of this IP, it is closer to 2500Base-X definition:
``PHY_INTERFACE_MODE_2500BASEX``
    This defines a variant of 1000BASE-X which is clocked 2.5 times
faster, than the 802.3 standard giving a fixed bit rate of 3.125Gbaud.

If HSGMII means SGMII over clocked to 2.5Gbps, the introduction needs to
be changed to "support SGMII/1000Base-X/2500Base-x".

[0]:
https://patchwork.kernel.org/patch/11057527/
> 
> 	 Andrew

Regards Landen