From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Lunn <andrew@lunn.ch>
Subject: Re: genphy_read_status() vs. 1000bT Pause capability
Date: Tue, 28 Mar 2017 03:09:40 +0200
Message-ID: <20170328010940.GG25549@lunn.ch>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On Tue, Mar 28, 2017 at 11:49:50AM +1100, Benjamin Herrenschmidt wrote:
> Hi !
> 
> I noticed that flow control isn't being enabled on a system I'm
> working on by default. I've tracked it down to two things:
> 
>  - The realtec.c PHY driver doesn't have Pause or Asym_Pause in
> its exposed capabilities. This is in part because PHY_GBIT_FEATURES
> does not include SUPPORTED_Pause and SUPPORTED_Asym_Pause. Is there
> a specific reason for that ?

Hi Ben

It is worth reading Documentation/networking/phy.txt

The MAC should set SUPPORTED_Pause and SUPPORTED_Asym_Pause if the MAC
supports these features. The PHY will then negotiate them.

	 Andrew