From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= <mans@mansr.com>
Subject: Re: [PATCH v5] net: ethernet: add driver for Aurora VLSI NB8800 Ethernet controller
Date: Wed, 11 Nov 2015 19:09:19 +0000
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	<20151111.112423.1751428739163066569.davem@davemloft.net>
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	<20151111.140252.2214540370641368590.davem@davemloft.net>
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Cc: romieu@fr.zoreil.com, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, slash.tmp@free.fr
To: David Miller <davem@davemloft.net>
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In-Reply-To: <20151111.140252.2214540370641368590.davem@davemloft.net> (David
	Miller's message of "Wed, 11 Nov 2015 14:02:52 -0500 (EST)")
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David Miller <davem@davemloft.net> writes:

> From: M=E5ns Rullg=E5rd <mans@mansr.com>
> Date: Wed, 11 Nov 2015 18:25:05 +0000
>
>> If the TX DMA channel is idle when start_xmit is called, it can be
>> started immediately.  Checking the DMA status and starting it if
>> idle has to be done atomically somehow.
>
> ->ndo_start_xmit() is guaranteed to be invoked atomically, protected
> by the TX queue spinlock.

Yes, but the DMA needs to be restarted from some other context if it wa=
s
busy when start_xmit checked.

--=20
M=E5ns Rullg=E5rd
mans@mansr.com