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Date:   Wed, 25 May 2022 21:56:29 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Tan Tee Min <tee.min.tan@linux.intel.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Voon Wei Feng <weifeng.voon@intel.com>,
        Sit Michael Wei Hong <michael.wei.hong.sit@intel.com>,
        Ling Pei Lee <pei.lee.ling@intel.com>,
        Looi Hong Aun <hong.aun.looi@intel.com>,
        Tan Tee Min <tee.min.tan@intel.com>
Subject: Re: [PATCH net-next 1/1] net: phy: dp83867: retrigger SGMII AN when
 link change
Message-ID: <20220525215629.69af5bf5@kernel.org>
In-Reply-To: <20220526013714.4119839-1-tee.min.tan@linux.intel.com>
References: <20220526013714.4119839-1-tee.min.tan@linux.intel.com>
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On Thu, 26 May 2022 09:37:14 +0800 Tan Tee Min wrote:
> There is a limitation in TI DP83867 PHY device where SGMII AN is only
> triggered once after the device is booted up. Even after the PHY TPI is
> down and up again, SGMII AN is not triggered and hence no new in-band
> message from PHY to MAC side SGMII.
> 
> This could cause an issue during power up, when PHY is up prior to MAC.
> At this condition, once MAC side SGMII is up, MAC side SGMII wouldn`t
> receive new in-band message from TI PHY with correct link status, speed
> and duplex info.
> 
> As suggested by TI, implemented a SW solution here to retrigger SGMII
> Auto-Neg whenever there is a link change.

Thanks, sounds like this bug has always been in the driver so we should
add:

Fixes: 2a10154abcb7 ("net: phy: dp83867: Add TI dp83867 phy")

Is that right? Getting a workaround like this into stable eventually
seems like a good idea so Fixes tag will help.