Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 25 Jun 2019 11:51:01 +0100
From:   Russell King - ARM Linux admin <linux@armlinux.org.uk>
To:     Parshuram Raju Thombare <pthombar@cadence.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        "nicolas.ferre@microchip.com" <nicolas.ferre@microchip.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "f.fainelli@gmail.com" <f.fainelli@gmail.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "hkallweit1@gmail.com" <hkallweit1@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Rafal Ciepiela <rafalc@cadence.com>,
        Anil Joy Varughese <aniljoy@cadence.com>,
        Piotr Sroka <piotrs@cadence.com>
Subject: Re: [PATCH v4 4/5] net: macb: add support for high speed interface
Message-ID: <20190625105101.xvcwgt3jh5pk7p2x@shell.armlinux.org.uk>
References: <1561281419-6030-1-git-send-email-pthombar@cadence.com>
 <1561281806-13991-1-git-send-email-pthombar@cadence.com>
 <20190623150902.GB28942@lunn.ch>
 <CO2PR07MB2469FDA06C3F8848290013B8C1E00@CO2PR07MB2469.namprd07.prod.outlook.com>
 <20190624131307.GA17872@lunn.ch>
 <SN2PR07MB2480DBE64F2550C0135335EEC1E30@SN2PR07MB2480.namprd07.prod.outlook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <SN2PR07MB2480DBE64F2550C0135335EEC1E30@SN2PR07MB2480.namprd07.prod.outlook.com>
User-Agent: NeoMutt/20170113 (1.7.2)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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