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Subject: Re: [RFC-PATCH] net: stmmac: Add KR port support.
To:     Daniel Walker <danielwa@cisco.com>,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Russell King <linux@armlinux.org.uk>
Cc:     Balamurugan Selvarajan <balamsel@cisco.com>,
        xe-linux-external@cisco.com,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20210729234443.1713722-1-danielwa@cisco.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <81fca68f-e0c4-ce02-6b2b-e5c22a0c3152@gmail.com>
Date:   Thu, 29 Jul 2021 17:10:45 -0700
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On 7/29/21 4:44 PM, Daniel Walker wrote:
> From: Balamurugan Selvarajan <balamsel@cisco.com>
> 
> For KR port the mii interface is a chip-to-chip
> interface without a mechanical connector. So PHY
> inits are not applicable. In this case MAC is
> configured to operate at forced speed(1000Mbps)
> and full duplex. Modified driver to accommodate
> PHY and NON-PHY mode.
> 
> Cc: xe-linux-external@cisco.com
> Signed-off-by: Balamurugan Selvarajan <balamsel@cisco.com>
> Signed-off-by: Daniel Walker <danielwa@cisco.com>

You are not adding KR support per-se, you are just hacking the driver so
it is happy with an unspecified phy_interface_t value and assuming
1000Mbits/sec, this is not going to work.

Just add KR/backplane properly or use a fixed-link property hardcoded
for 1000Mbits/sec and be done with it with no hacking, which would be
just way better than what is proposed here.
-- 
Florian