From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [RFC + Queries] Flow of PCI passthrough in ARM Date: Fri, 3 Oct 2014 10:01:10 +0100 Message-ID: <1412326870.423.14.camel@citrix.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefano Stabellini Cc: Anup Patel , Vijay Kilari , Prasun Kapoor , manish.jaggi@caviumnetworks.com, Julien Grall , xen-devel , psawargaonkar@linaro.org, Matt.Evans@arm.com, Dave.Martin@arm.com, manish jaggi List-Id: xen-devel@lists.xenproject.org On Thu, 2014-10-02 at 17:59 +0100, Stefano Stabellini wrote: > On Thu, 2 Oct 2014, Stefano Stabellini wrote: > > > >> >> using this the ITS emulation code in xen is able to trap ITS command > > > >> >> writes by driver. > > > >> >> But we are facing a problem now, where your help is needed > > Actually given that you are talking about the virtual ITS, why do you > need the real Device ID or Stream ID of the passthrough device in the > guest at all? Shouldn't you just be generating a bunch of virtual IDs > instead? > > Let's take a step back: why do you need *real* IDs to program a > *virtual* ITS? Ack, I'm having a great deal of trouble figuring out why the guest would ever see a physical hardware identifier of any kind. Ian.