Re: [PATCH v4 4/5] net: macb: add support for high speed interface

From: Russell King - ARM Linux admin
Date: Tue Jun 25 2019 - 06:51:15 EST


On Tue, Jun 25, 2019 at 08:26:29AM +0000, Parshuram Raju Thombare wrote:
> Hi Andrew,
>
> >What i'm saying is that the USXGMII rate is fixed. So why do you need a device
> >tree property for the SERDES rate?
> This is based on Cisco USXGMII specification, it specify USXGMII 5G and USXGMII 10G.
> Sorry I can't share that document here.

The closed nature of the USXGMII spec makes it very hard for us to know
whether your implementation is correct or not.

I have some documentation which suggests that USVGMII is a USXGMII link
running at "5GR" rate as opposed to USXGMII running at "10GR" rate.

So, I think 5G mode should be left out until it becomes clear that (a)
we should specify it as USXGMII with a 5G rate, or as USVGMII.

--
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