From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52042) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XADaE-0002zL-Oz for qemu-devel@nongnu.org; Thu, 24 Jul 2014 03:37:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XADa8-00067i-Qw for qemu-devel@nongnu.org; Thu, 24 Jul 2014 03:36:58 -0400 Received: from mail-wg0-f48.google.com ([74.125.82.48]:54904) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XADa8-000666-Kg for qemu-devel@nongnu.org; Thu, 24 Jul 2014 03:36:52 -0400 Received: by mail-wg0-f48.google.com with SMTP id x13so2240087wgg.31 for ; Thu, 24 Jul 2014 00:36:51 -0700 (PDT) Message-ID: <53D0B779.7090503@linaro.org> Date: Thu, 24 Jul 2014 09:36:25 +0200 From: Eric Auger MIME-Version: 1.0 References: <1404716892-15600-1-git-send-email-eric.auger@linaro.org> <1404716892-15600-6-git-send-email-eric.auger@linaro.org> <53BBF781.9070102@suse.de> <53CFD5D2.4090602@linaro.org> <53D03F05.7000603@suse.de> In-Reply-To: <53D03F05.7000603@suse.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 5/7] hw/core/sysbus: add fdt_add_node method List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf , eric.auger@st.com, christoffer.dall@linaro.org, qemu-devel@nongnu.org, kim.phillips@freescale.com, a.rigo@virtualopensystems.com Cc: peter.maydell@linaro.org, patches@linaro.org, stuart.yoder@freescale.com, alex.williamson@redhat.com, a.motakis@virtualopensystems.com, kvmarm@lists.cs.columbia.edu On 07/24/2014 01:02 AM, Alexander Graf wrote: > > On 23.07.14 17:33, Eric Auger wrote: >> On 07/08/2014 03:52 PM, Alexander Graf wrote: >>> On 07.07.14 09:08, Eric Auger wrote: >>>> This method is meant to be called on sysbus device dynamic >>>> instantiation (-device option). Devices that support this >>>> kind of instantiation must implement this method. >>>> >>>> Signed-off-by: Eric Auger >>> For the reason I stated earlier, I don't think it's a good idea to put >>> device tree code into our device models. >> Hi Alex, >> >> I would propose we discuss that topic during next KVM call if you are >> available. > > I lost track when that would be. Next week would work fine, the week > after not :). Hi Alex, Unfortunately I think the last one was this week. If you are available next week I would propose to setup a short call next week. Who are the required people in the call aside us and Peter? > >> Hope Peter will be available to join too. Because I feel >> stuck between not putting things in the machine file (1) - obviously we >> could put them in a helper module (2) - and not putting them in the >> device (3). >> >> Whatever the solution I fear we are going to pollute something: Any time >> a new device wants to support dynamic instantiation, we would need to >> modify the machine file or the helper module with 1 and 2 resp. In case >> we put it in the device we pollute this latter... >> >> My hope was that quite few QEMU platform devices would need to support >> that feature and hence would need to implement this dt node generation >> method. To me dynamic instantiation of platform device was not the >> mainstream solution. > > Quite frankly I don't think it'd be that many. I think we'll cover 99.9% > of all use cases if we just enable it for the virt machines of e500 and > arm. > >> Then there is the fundamental question of technical feasibility of >> devising a generic PlatformParams that match all the specialization >> needs? Here I miss experience. In case we know the machine type and a >> small set of additional fields couldn't we do the adaptations you talked >> about, related to IRQs? > > The problem is that I don't know all the boards and different things > people come up with either. There's also no reason machine files have to > stick to the "platform bus" model - they could just take those devices > and stick them into an existing other virtual bus. > > I don't feel comfortable generalizing something where I'm pretty sure > things will blow up sooner or later. ok Best Regards Eric > > > Alex >