From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH 05/10] xen/arm: vgic-v3: Document the current restrictions Date: Tue, 20 Jan 2015 16:00:43 +0000 Message-ID: <1421769643.10440.309.camel@citrix.com> References: <1421684957-29884-1-git-send-email-julien.grall@linaro.org> <1421684957-29884-6-git-send-email-julien.grall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YDbXJ-00073Z-Ga for xen-devel@lists.xenproject.org; Tue, 20 Jan 2015 16:20:13 +0000 In-Reply-To: <1421684957-29884-6-git-send-email-julien.grall@linaro.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Julien Grall Cc: xen-devel@lists.xenproject.org, tim@xen.org, stefano.stabellini@citrix.com List-Id: xen-devel@lists.xenproject.org On Mon, 2015-01-19 at 16:29 +0000, Julien Grall wrote: > The current vGIC v3 driver doesn't fully implement GICv3 spec: > - GICv3 backward compatibility is not supported (GICD_CTLR.ARE = 0) I think you meant GICv2 here as you did in the code. In which case I believe this is optional in the spec, i.e. we can be compliant and still not implement this. That's not to say it isn't desirable, but this is a TODO item, not a spec non-conformity issue. > - A processor can only access his own redistributor. For buggy > assumption, the current code bank the redistributors MMIO. What assumption? It's not clear if you mean that a foreign redistributor should not be accessible and is, or if it should be accessible and isn't. > > Signed-off-by: Julien Grall > --- > xen/arch/arm/vgic-v3.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/xen/arch/arm/vgic-v3.c b/xen/arch/arm/vgic-v3.c > index 1fa1413..9818a6b 100644 > --- a/xen/arch/arm/vgic-v3.c > +++ b/xen/arch/arm/vgic-v3.c > @@ -16,6 +16,11 @@ > * but WITHOUT ANY WARRANTY; without even the implied warranty of > * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > * GNU General Public License for more details. > + * > + * Current limitation of the vGIC v3: > + * - GICv2 backward compatibility is not supported (GICD_CTRL.ARE = 0) > + * - A processor can only access his own redistributor. For buggy > + * assumption, the current code bank the redistributors MMIO > */ > > #include