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Date: Sat, 14 May 2016 08:20:35 +0530
Message-ID: <CAFcVECJjHRYUmtN3Gha-zNz+4JvXRH-BY+eEumdboaREp1D4Ow@mail.gmail.com>
Subject: Re: [RFC PATCH 2/2] Documentation: devictree: Add macb mdio bindings
From: Harini Katakam <harinikatakamlinux@gmail.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: Harini Katakam <harini.katakam@xilinx.com>,
        Nicolas Ferre <nicolas.ferre@atmel.com>, davem@davemloft.net,
        Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        "ijc+devicetree@hellion.org.uk" <ijc+devicetree@hellion.org.uk>,
        Kumar Gala <galak@codeaurora.org>, netdev@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        Punnaiah Choudary Kalluri <punnaia@xilinx.com>,
        "michals@xilinx.com" <michals@xilinx.com>
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HI Andrew,

On Fri, May 13, 2016 at 11:13 PM, Andrew Lunn <andrew@lunn.ch> wrote:
> Hi Harini
>
> Is this backward compatible? Will devices using the old binding still
> work?

It isn't right now.
I will have to assign the bus read/write functions conditionally in order to
do that - I'll see if I can make it clean.

>
>   /* Disable RX and TX (XXX: Should we halt the transmission
>    * more gracefully?)
>     */
> -   macb_writel(bp, NCR, 0);
> +   ctrl = macb_readl(bp, NCR);
> +   ctrl &= ~(MACB_BIT(RE) | MACB_BIT(TE));
> +   macb_writel(bp, NCR, ctrl);
>
>         /* Clear the stats registers (XXX: Update stats first?) */
> -       macb_writel(bp, NCR, MACB_BIT(CLRSTAT));
> +       ctrl |= MACB_BIT(CLRSTAT);
> +       macb_writel(bp, NCR, ctrl);
>
>         /* Clear all status flags */
>         macb_writel(bp, TSR, -1);
>
> It is not clear to me what this part has to do with MDIO.
>

Sorry, I'll move this to a separate patch in my next version.
It is intended to write those registers without disturbing reserved bits.

Regards,
Harini