From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Uclinux-dist-devel] [PATCH 1/5] netdev: bfin_mac: Blackfin
 EMAC interrupt may not be shared
Date: Fri, 29 May 2009 15:09:28 -0700 (PDT)
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Cc: Michael.Hennerich@analog.com, netdev@vger.kernel.org,
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=46rom: Mike Frysinger <vapier.adi@gmail.com>
Date: Fri, 29 May 2009 07:45:05 -0400

> On Fri, May 29, 2009 at 07:28, David Miller wrote:
>> From: Mike Frysinger <vapier.adi@gmail.com>
>>> why implement extra over head in an interrupt handler to support an
>>> operating mode the hardware can never support.
>>
>> What overhead? =A0It should be pretty easy to see if the device
>> is really indicating an interrupt or not :-)
>=20
> which would involve reading system mmrs which are clocked at the
> system frequency and thus make the core stall

And the core doesn't stall reading in these cache lines that the chip
has just DMA'd to?

I think you're throwing the baby out with the bath water :-)