From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [RFC PATCH v1 02/10] xen/arm: register mmio handler at runtime Date: Thu, 27 Mar 2014 15:02:21 +0000 Message-ID: <53343D7D.5090407@linaro.org> References: <1395238631-2024-1-git-send-email-vijay.kilari@gmail.com> <1395238631-2024-3-git-send-email-vijay.kilari@gmail.com> <1395422249.25521.45.camel@kazak.uk.xensource.com> <532C7589.2040009@linaro.org> <5332E86D.5020508@linaro.org> 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: Vijay Kilari Cc: Ian Campbell , Stefano Stabellini , Prasun Kapoor , Vijaya Kumar K , xen-devel@lists.xen.org, Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 03/27/2014 05:40 AM, Vijay Kilari wrote: > On Wed, Mar 26, 2014 at 8:17 PM, Julien Grall wrote: >> On 03/26/2014 12:29 PM, Vijay Kilari wrote: >>> Hi Julien, >>> >>> >>> On Fri, Mar 21, 2014 at 10:53 PM, Julien Grall wrote: >>>> On 03/21/2014 05:17 PM, Ian Campbell wrote: >>>>> On Wed, 2014-03-19 at 19:47 +0530, vijay.kilari@gmail.com wrote: >>>>>> From: Vijaya Kumar K >>>>>> >>>>>> mmio handlers are registers at compile time >>>>>> for drivers like vuart and vgic. >>>>>> Make mmio handler registered at runtime by >>>>>> creating linked list of mmio handlers >>>>> >>>>> I'm not convinced of the need for this, certainly the vgic side can just >>>>> demux into v2 or v3 as necessary. >>>> >>>> Demux the code just add an indirection. We could have a list of mmio >>>> handler per domain and rely on it to call the right handler. A bit like x86. >>>> >>> Until Andrii adds IOMMU handling should keep this patch? and adopt >>> to it later? >> >> I'm not sure to understand. IHMO, it doesn't sound right to upstream a >> patch that we know it will be superseded in a couple of months. Why >> can't you rework your patch to have it in good shape now? >> > I assume that Andii's patch will be required to make mmio handlers > per domain. If not let me know references in x86 that I can make it > per domain specific mmio handlers. I have already pointed out to the x86 code few mails before. You can look at xen/arch/x86/intercept.c. > > I was more inclined to go with this patch for now because it helps to > go ahead with GICv3 and anything beyond this can be managed separately. > Please let me know you opinion. As I said on the email you answered, I'm not in favor to allow a this patch that we know it will superseded in less than a couple of months. It won't take you longer time than addressing the current requests on this patch. In last resort, you can use the demux solution from Ian. I don't agree with it but it's better than upstreaming an half-feature for no valid reason. Regards, -- Julien Grall