From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [Qemu-devel] [PATCHv2 4/8] Store IDE bus id in IDEBus structure for easy access. Date: Sat, 6 Nov 2010 13:37:24 +0200 Message-ID: <20101106113724.GE9617@redhat.com> References: <20101104080730.GA6018@redhat.com> <20101104092348.GB6018@redhat.com> <20101104152631.GA14910@redhat.com> <20101105155427.GB9617@redhat.com> <20101105184456.GD9617@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: blauwirbel@gmail.com, alex.williamson@redhat.com, qemu-devel@nongnu.org, kvm@vger.kernel.org To: Markus Armbruster Return-path: Received: from mx1.redhat.com ([209.132.183.28]:17759 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753159Ab0KFLh2 (ORCPT ); Sat, 6 Nov 2010 07:37:28 -0400 Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Sat, Nov 06, 2010 at 10:25:31AM +0100, Markus Armbruster wrote: > Gleb Natapov writes: > > > On Fri, Nov 05, 2010 at 05:31:38PM +0100, Markus Armbruster wrote: > >> Gleb Natapov writes: > >> > >> > On Fri, Nov 05, 2010 at 03:04:05PM +0100, Markus Armbruster wrote: > >> [...] > >> >> >> >> There has been quite some discussion on "canonical path" on the list, > >> >> >> >> but no consensus. Ironically, one of the places where we got stuck was > >> >> >> >> ISA. You cut right through that, so that's progress. Maybe people > >> >> >> >> aren't looking ;) > >> >> >> > That is funny since the problem was already solved looong time ago. Just > >> >> >> > look at Open Firmware device path. They are capable of addressing all > >> >> >> > devices just fine, ISA devices included. What specific problem you had > >> >> >> > with ISA bus? > >> >> >> > >> >> >> Lack of consensus. I was in favour of using I/O base, just like you do. > >> >> >> There were worries about ISA devices not using any I/O ports. > >> >> > There is a solution for that problem for almost 15 years and we are > >> >> > still looking for consensus on qemu list?! Here is ISA device binding > >> >> > spec for Open Firmware: http://playground.sun.com/1275/bindings/isa/isa0_4d.ps > >> >> > If ISA device have no IO ports MMIO is used. > >> >> > >> >> Precedence should promote consensus, but it can't replace it. If you > >> >> can push the list to consensus, more power to you. > >> > I do not see disagreement right now :) You are saying you agree. Blue > >> > Swirl asked me to use Open Firmware so I assume he agrees to. So who is > >> > against and what are his arguments? > >> > >> Start here: > >> > >> http://lists.nongnu.org/archive/html/qemu-devel/2010-06/msg01618.html > > > > I saw this in fact. The wouldn't agree with this device path proposal > > too. It mixes qemu internal names (which is a big no-no for my purpose) > > and bus addresses. Paul made sensible points there and if you look > > closely what he proposes is what I implemented here. Regarding ISA > > ("busses that don't have a consistent addressing scheme" he called it) > > he himself proposed to use address of the first IO port/memory region > > as an ID. This is what is already implemented by my patch. > > You don't have to convince me; I was with Paul in that thread. > So who should I convince :)? Alex? He is CCed. Jan? I do not see him complaining here. > Regarding DeviceInfo member name values being QEMU internal: hardly. > They're ABI. They're what we use to identify device types on external > interfaces including command line, human monitor and QMP. Correct. They are ABI since they are user visible. But they describe device type where I prefer to have a field that specifies device functionality for cases when one driver handles multiple devices in a guest. So to clarify: "name" will work (that is why I use it when driver_name is not set), but I want something more optimal. -- Gleb.