From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH v1 8/8] xen/arm: vgic-v3: Support 32-bit access for 64-bit registers Date: Tue, 29 Sep 2015 14:27:35 +0100 Message-ID: <1443533255.16718.73.camel@citrix.com> References: <1443192698-16163-1-git-send-email-julien.grall@citrix.com> <1443192698-16163-9-git-send-email-julien.grall@citrix.com> 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 1ZguwX-0000k1-1B for xen-devel@lists.xenproject.org; Tue, 29 Sep 2015 13:27:41 +0000 In-Reply-To: <1443192698-16163-9-git-send-email-julien.grall@citrix.com> 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 , xen-devel@lists.xenproject.org Cc: Vijaya.Kumar@caviumnetworks.com, stefano.stabellini@citrix.com, manish.jaggi@caviumnetworks.com, vijay.kilari@gmail.com List-Id: xen-devel@lists.xenproject.org On Fri, 2015-09-25 at 15:51 +0100, Julien Grall wrote: > Based on 8.1.3 (IHI 0069A), unless stated otherwise, the 64-bit registers > supports both 32-bit and 64-bits access. > > All the registers we properly emulate (i.e not RAZ/WI) supports 32-bit > access. > > For RAZ/WI, it's also seems to be the case but I'm not 100% sure. Anyway, > emulating 32-bit access for them doesn't hurt. Note that we would need > some extra care when they will be implemented (for instance > GICR_PROPBASER). > > Signed-off-by: Julien Grall Acked-by: Ian Campbell > --- > This is technically fixing boot of FreeBSD ARM64 guest with GICv3. > > AFAICT, Linux is not using 32-bit access in the GICv3 code expect > for the ITS (which we don't support yet). > > So this patch is a good candiate for Xen 4.6. Although this patch is > heavily depend on previous patches. It may be possible to shuffle > and move the "opmitization" patches towards the end. I haven't yet > done that because I feel this series makes more sense in the current > order. I think if we let it bake in unstable for a bit to gain confidence we could consider backporting the whole lot to either 4.6.1 or .2.