From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH] Fix intel_detect_pch() to work in xen environment. Date: Thu, 20 Dec 2012 08:13:30 -0800 Message-ID: <20121220081330.19f30c3e@jbarnes-desktop> References: <20121218085341.03d9cab3@jbarnes-desktop> <20121218102012.1866ea85@jbarnes-desktop> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from oproxy9.bluehost.com (oproxy9.bluehost.com [69.89.24.6]) by gabe.freedesktop.org (Postfix) with SMTP id A71D8E603F for ; Thu, 20 Dec 2012 08:13:01 -0800 (PST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: "G.R." Cc: Stefano Stabellini , intel-gfx@lists.freedesktop.org, "Dong, Eddie" , "Xu, Dongxiao" , "Zhang, Xiantao" List-Id: intel-gfx@lists.freedesktop.org On Thu, 20 Dec 2012 12:04:11 +0800 "G.R." wrote: > On Wed, Dec 19, 2012 at 2:20 AM, Jesse Barnes wrote: > >> > > >> > I'd like to see a comment about this being for Xen in here, and I > >> > wonder if there are other places where we might have to worry about the > >> > Xen implementation. In that case, setting a flag in dev_priv when we > >> > don't find the PCH where we expect would be a good idea too. > >> > > >> > >> I can add a comment here if the overall idea is acceptable to you. > >> But there is already a comment mentioning that the ISA bridge check is > >> for virtualization: > >> > >> 404 /* > >> 405 * The reason to probe ISA bridge instead of Dev31:Fun0 is to > >> 406 * make graphics device passthrough work easy for VMM, that only > >> 407 * need to expose ISA bridge to let driver know the real hardware > >> 408 * underneath. This is a requirement from virtualization team. > >> 409 */ > >> > >> > Ack on the general idea though; I'd like us to be able to run under Xen > >> > without modification. > >> > > >> > >> Stefano may be able to comment if it's feasible to achieve zero > >> modification in this case. > >> I believe this has something to do with getting rid of the PIIX3 > >> device provided by qemu. > >> > >> But generally I think it's very hard to achieve perfect emulation. > >> You can't always foresee what assumption a guest driver would make. > >> Maybe we need some compromise. > > > > I meant that I'd like to see any other patches required for Xen get > > merged, that way people won't have to patch their kernels for i915 > > under Xen. > > Hi Jesse, I think I need to resend the patch with proper comment to > have it formally accepted. > Any guide line for formal patch submission? Do I need to start a > separate thread? No, just cc Daniel Vetter. -- Jesse Barnes, Intel Open Source Technology Center