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Date: Mon, 5 Jun 2023 12:05:05 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Shannon Nelson <shannon.nelson@amd.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net, brett.creeley@amd.com,
 drivers@pensando.io, Nitya Sunkad <nitya.sunkad@amd.com>
Subject: Re: [PATCH net-next] ionic: add support for ethtool extended stat
 link_down_count
Message-ID: <20230605120505.71f518ae@kernel.org>
In-Reply-To: <be5f26b8-fbe5-841d-5469-3adcfc178ab3@amd.com>
References: <20230602173252.35711-1-shannon.nelson@amd.com>
	<20230602234708.03fbb00e@kernel.org>
	<be5f26b8-fbe5-841d-5469-3adcfc178ab3@amd.com>
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On Mon, 5 Jun 2023 09:26:25 -0700 Shannon Nelson wrote:
> > Hm, could you say more about motivation? The ethtool stat is supposed to
> > come from HW and represent PHY-level flap count. It's used primarily to
> > find bad cables in a datacenter. Is this also the use case for ionic?
> > It's unclear to me whether ionic interfaces are seeing an actual PHY or
> > just some virtual link state of the IPU and in the latter case it's not
> > really a match.  
> 
> This is a fair question - yes, it is possible that the FW could fake it, 
> but normally this is a signal from the HW.  However, I suppose it would 
> be best to only have the PF reporting this counter, and not the VFs, 
> which is currently the case here.  I'll have Nitya modify this for PF only.

Perfect, thanks!