From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [kvmarm] [RFC PATCH 0/3] KVM: ARM: Get rid of hardcoded VGIC addresses Date: Fri, 26 Oct 2012 12:22:28 +0200 Message-ID: <508A6464.9080901@siemens.com> References: <1350173065-35350-1-git-send-email-c.dall@virtualopensystems.com> <507F172D.2030802@suse.de> <20121017221022.GA4333@bloggs.ozlabs.ibm.com> <1350518331.4678.114.camel@pasglop> <508675FC.7090901@siemens.com> <20121024005017.GA17834@bloggs.ozlabs.ibm.com> <5089656A.9010704@redhat.com> <5089699D.3050004@siemens.com> <50898479.8060402@redhat.com> <1351194021.2728.170.camel@pasglop> <508A5EE3.6070709@redhat.com> <508A62BB.4010209@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Peter Maydell , Benjamin Herrenschmidt , Paul Mackerras , Christoffer Dall , Alexander Graf , "kvmarm@lists.cs.columbia.edu" , "kvm@vger.kernel.org" , kvm-ppc To: Paolo Bonzini Return-path: In-Reply-To: <508A62BB.4010209@redhat.com> Sender: kvm-ppc-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 2012-10-26 12:15, Paolo Bonzini wrote: > Il 26/10/2012 12:09, Peter Maydell ha scritto: >>>> >>>> The other problem is configuring the redirection table. If you need >64 >>>> sources you need ioctls like KVM_GET/SET_IRQCHIP_ONE_REG. >> Why would you want an extra ONE_REG-like ioctl? The existing ONE_REG >> ioctls have plenty of space in the ID range to allow you to devote >> a subsection of it to your irqchip. (This is exactly how the ARM >> VGIC save/load is going to work.) > > Ok, I stand corrected. :) > >> Whether you want to do startup configuration and board wiring via >> the same ioctl that handles runtime state save/load/migration is >> a different question, of course. > > QEMU's MSI-X routing is not x86-specific, so it should use the same > KVM_SET_GSI_ROUTING ioctl that x86 uses. And it's not only MSI[-X]. Most IRQ sources need to be rounted, either from userspace or from irqfd or from some other in-kernel source to a specific IRQ controller. That allows to customize things according to a specific board / SoC emulation. Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux