From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Xiang, Haihao" Subject: Re: [Intel gfx][i-g-t PATCH 3/4] rendercopy/bdw: A workaround for 3D pipeline Date: Mon, 09 Dec 2013 12:47:36 +0800 Message-ID: <1386564456.30122.37.camel@xhh-ivb32> References: <1386320087-3017-1-git-send-email-haihao.xiang@intel.com> <1386320087-3017-3-git-send-email-haihao.xiang@intel.com> <20131206133052.GF16277@strange.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id A81B5FAEDE for ; Sun, 8 Dec 2013 20:46:14 -0800 (PST) In-Reply-To: <20131206133052.GF16277@strange.amr.corp.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: Damien Lespiau Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Fri, 2013-12-06 at 13:30 +0000, Damien Lespiau wrote: > On Fri, Dec 06, 2013 at 04:54:46PM +0800, Xiang, Haihao wrote: > > From: "Xiang, Haihao" > > > > Emit PIPELINE_SELECT twice and make sure the commands in > > the first batch buffer have been done. > > > > However I don't know why this works !!! > > Hum :) on one hand, it's great that you found this w/a, on the other > hand, I'm not comfortable with not understanding why this works. Thanks for the comments, actually I am not comfortable with it too. gem_render_copy passed after I happened to run gem_media_fill first, so I am curious which setting in gem_media_fill impact the result. Finally I found it works if I emit PIPELINE_SELECT in a separated batch first. > So far > what we know (I don't have Silicon that can't test anything): > > - Ken was saying that mesa doesn't need this. > - There are a bunch of W/A around FF units clock gating, might worth > checking that we're not hiting WaDisableFfDopClockGating or one of > those 3D Vs GPGPU pipelines ones. > This could happen to you but not to Ken because you have been > switching between 3D and media pipeline with the 2 igt tests. > - In any case, doing a pass on the W/A sounds like a good idea > - I'd be interested to know if there a even more minimal batch that > works (say an empty batch), or if the active ingredient is the > pipeline switch. Oh, it works even with an batch which has only MI_BATCH_BUFFER_END. > > If people want to push the patch to make progress on other parts, I > guess that's fine, but we'll need to dig deeper here. Agree, we should look into the issue to find the real root cause. >