From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [RFT] e100 driver on ARM
Date: Thu, 26 Apr 2007 09:19:34 -0700
Message-ID: <4630D116.4080202@zytor.com>
References: <44FC0261.6010807@garzik.org> <20060904123123.GB1285@xi.wantstofly.org> <460AF480.7050609@intel.com> <460B4BF2.1070803@roinet.com> <20070329141041.GA3510@csclub.uwaterloo.ca> <46239138.4040408@roinet.com> <20070417173507.GB5575@csclub.uwaterloo.ca>
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Cc: David Acker <dacker@roinet.com>,
	"Kok, Auke" <auke-jan.h.kok@intel.com>,
	Lennert Buytenhek <buytenh@wantstofly.org>,
	Jeff Garzik <jeff@garzik.org>,
	Netdev List <netdev@vger.kernel.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@osdl.org>,
	Russell King <rmk+lkml@arm.linux.org.uk>
To: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
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Lennart Sorensen wrote:
> 
> My suspicision (although it is only that) is that the PXA255 trying to
> access memory may cause interruptions in PCI bus master transfers, which
> is of course not permitted by the PCI spec (at least the way I read it).

Why wouldn't that be permitted?  It, in fact, happens all the time (the
host bridge withdraws the GNT# line and raises STOP#, which does a
Termination With Data of the bus transfer.)  This is a normal event and
if you can't handle it you won't work with many host bridges at all.

	-hpa