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Date:   Thu, 10 Sep 2020 13:30:58 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Oded Gabbay <oded.gabbay@gmail.com>
Cc:     "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>,
        netdev@vger.kernel.org, SW_Drivers <SW_Drivers@habana.ai>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "David S. Miller" <davem@davemloft.net>,
        Omer Shpigelman <oshpigelman@habana.ai>
Subject: Re: [PATCH 12/15] habanalabs/gaudi: add debugfs entries for the NIC
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On Thu, 10 Sep 2020 23:17:59 +0300 Oded Gabbay wrote:
> > Doesn't seem like this one shows any more information than can be
> > queried with ethtool, right?  
> correct, it just displays it in a format that is much more readable

You can cat /sys/class/net/$ifc/carrier if you want 0/1.

> > > nic_mac_loopback
> > > is to set a port to loopback mode and out of it. It's not really
> > > configuration but rather a mode change.  
> >
> > What is this loopback for? Testing?  
> 
> Correct.

Loopback test is commonly implemented via ethtool -t