From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= <mans@mansr.com>
Subject: Re: [RFC PATCH v1] net: ethernet: nb8800: Reset HW block in ndo_open
Date: Sat, 29 Jul 2017 13:51:42 +0100
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Cc: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
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To: Mason <slash.tmp@free.fr>
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Mason <slash.tmp@free.fr> writes:

> On 29/07/2017 14:05, Måns Rullgård wrote:
>
>> Mason writes:
>> 
>>> I'll take this opportunity to change flow control to
>>> off by default (it breaks several 100 Mbps switches).
>> 
>> I was told to have it on by default.  This is what most other drivers
>> do too.  If you have faulty switches, that's your problem.
>
> Or maybe the fault is in the HW implementation, and
> it is the board's fault that the connection is hosed.
>
> How many switches did you test the driver on?
>
> We tested 4 switches, and DHCP failed on 3 of them.
> Disabling pause frames "fixed" that.

Do those switches work with other NICs?

> I could spend weeks testing dozens of switches, but
> I have to prioritize. Ethernet flow control is simply
> not an important feature in the market the SoC is
> intended for.

Sure, flow control is rarely needed with well behaved systems.

-- 
Måns Rullgård