From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [Uclinux-dist-devel] [PATCH 1/5] netdev: bfin_mac: Blackfin EMAC interrupt may not be shared Date: Fri, 29 May 2009 15:45:34 -0700 (PDT) Message-ID: <20090529.154534.37038134.davem@davemloft.net> References: <8bd0f97a0905291513m780898e9j6bd4c0b3b9ae8528@mail.gmail.com> <20090529.151816.232829085.davem@davemloft.net> <8bd0f97a0905291521m35731e0bra828cb09d0929974@mail.gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Michael.Hennerich@analog.com, netdev@vger.kernel.org, uclinux-dist-devel@blackfin.uclinux.org To: vapier.adi@gmail.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:33011 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752239AbZE2Wpf convert rfc822-to-8bit (ORCPT ); Fri, 29 May 2009 18:45:35 -0400 In-Reply-To: <8bd0f97a0905291521m35731e0bra828cb09d0929974@mail.gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: =46rom: Mike Frysinger Date: Fri, 29 May 2009 18:21:41 -0400 > On Fri, May 29, 2009 at 18:18, David Miller wrote: >> From: Mike Frysinger >>> the difference is that one of these is required in order for anythi= ng >>> to get done and the other is always useless noise. =A0also, the Bla= ckfin >>> core does do speculative data fetching on external memory, but not >>> MMRs, so the stalling due to the data cache line fills will be >>> mitigated unlike the useless MMR reads. >> >> You only need to read the register if the descriptor status is not >> ready yet, and you're just spinning in that case anyways. >> >> I doubt it makes any real difference if implemented properly. >> >> But I guess it's more fun to speculate than to actually try it out. >> :-/ >=20 > and i guess it's more fun to waste time attempting to support an > operating mode that the hardware has never and most likely will never > support I guess I'll apply your patch :-)