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Subject: Re: [PATCH RFC net 2/2] net: dsa: lantiq_gswip: Configure all
 remaining GSWIP_MII_CFG bits
To:     Andrew Lunn <andrew@lunn.ch>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc:     hauke@hauke-m.de, vivien.didelot@gmail.com, olteanv@gmail.com,
        netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org,
        linux@armlinux.org.uk, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
References: <20210406203508.476122-1-martin.blumenstingl@googlemail.com>
 <20210406203508.476122-3-martin.blumenstingl@googlemail.com>
 <YGz9hMcgZ1sUkgLO@lunn.ch>
From:   Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <98ef4831-27eb-48d4-1421-c6496b174659@gmail.com>
Date:   Wed, 7 Apr 2021 09:47:32 -0700
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On 4/6/2021 5:32 PM, Andrew Lunn wrote:
>>  	case PHY_INTERFACE_MODE_RGMII:
>>  	case PHY_INTERFACE_MODE_RGMII_ID:
>>  	case PHY_INTERFACE_MODE_RGMII_RXID:
>>  	case PHY_INTERFACE_MODE_RGMII_TXID:
>>  		miicfg |= GSWIP_MII_CFG_MODE_RGMII;
>> +
>> +		if (phylink_autoneg_inband(mode))
>> +			miicfg |= GSWIP_MII_CFG_RGMII_IBS;
> 
> Is there any other MAC driver doing this? Are there any boards
> actually enabling it? Since it is so odd, if there is nothing using
> it, i would be tempted to leave this out.

Some PHYs (Broadcom namely) support suppressing the RGMII in-band
signaling towards the MAC, so if the MAC relies on that signaling to
configure itself based on what the PHY reports this may not work.
-- 
Florian