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Date: Thu, 28 Dec 2023 15:09:57 +0100
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Subject: Re: [PATCH v2 1/1] net: phy: micrel: Add workaround for incomplete
 autonegotiation
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To: Asmaa Mnebhi <asmaa@nvidia.com>, Florian Fainelli <f.fainelli@gmail.com>,
 "davem@davemloft.net" <davem@davemloft.net>,
 "marek.mojik@nic.cz" <marek.mojik@nic.cz>,
 "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Cc: David Thompson <davthompson@nvidia.com>,
 "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <20231227231657.15152-1-asmaa@nvidia.com>
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On 28.12.2023 14:37, Asmaa Mnebhi wrote:
>  > On 12/28/2023 12:16 AM, Asmaa Mnebhi wrote:
>>> Very rarely, the KSZ9031 fails to complete autonegotiation although it
>>> was initiated via phy_start(). As a result, the link stays down.
>>> Restarting autonegotiation when in this state solves the issue.
>>>
>>> Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
>>
>> Is there a Micrel errata associated with this work around that could be
>> referenced here?
> 
> Hi Florian,
> 
> No there isn’t. This is based on observations and comparison with the behavior and testing of other PHYs. For example, we don’t see this issue with the Vitesse PHY.
> 
The Microchip KSZ9031 errata documentation lists few link-related errata.
May any of these be relevant in your case? If not, please check with Microchip.
KSZ9031 isn't new, and most likely we would have seen such reports before,
if there's an actual issue.
I'd like to avoid that we add code to work around an issue that is specific
to your setup.

> Thanks.
> Asmaa