From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH] drm/i915: paper over missed irq issues with force wake vodoo Date: Sat, 14 Jan 2012 00:52:31 +0100 Message-ID: <20120113235231.GE3843@phenom.ffwll.local> References: <1325702445-2231-1-git-send-email-daniel.vetter@ffwll.ch> <86lipb367b.fsf@sumi.keithp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-we0-f177.google.com (mail-we0-f177.google.com [74.125.82.177]) by gabe.freedesktop.org (Postfix) with ESMTP id 849B69EF96 for ; Fri, 13 Jan 2012 15:50:25 -0800 (PST) Received: by werp12 with SMTP id p12so1042053wer.36 for ; Fri, 13 Jan 2012 15:50:24 -0800 (PST) Content-Disposition: inline In-Reply-To: <86lipb367b.fsf@sumi.keithp.com> 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: Keith Packard Cc: Daniel Vetter , intel-gfx , Eugeni Dodonov , stable@kernel.org List-Id: intel-gfx@lists.freedesktop.org On Fri, Jan 13, 2012 at 08:42:00AM -0800, Keith Packard wrote: > On Wed, 4 Jan 2012 19:40:45 +0100, Daniel Vetter wrote: > > > Two things seem to do the trick on my ivb machine here: > > - prevent the gt from powering down while waiting for seqno > > notification interrupts by grabbing the force_wake in get_irq (and > > dropping it in put_irq again). > > - ordering writes from the ring's CS by reading a CS register, ACTHD > > seems to work. > > I've rebased this code on top of drm-intel-fixes and pushed it to my > forcewake-spinlock branch. I'd like to get this pushed to > drm-intel-fixes in the next couple of days, get some QA coverage and > then get it merged to master so that we can get some community testing > early in the 3.3 cycle. A few quick comments: - I think we need to amend the commit msg of the voodoo patch with the piece of doc I've discovered. If you want I can send out a v3 with that. - I think the HWSTAM revert is material for -next - Can you post your 3 patches on intel-gfx, I think I can shoot at them a bit ;-) acc101d drm/i915: Hold gt_lock across forcewake register reads Imo this is a simple cleanup (reading forcewake-protected registers isn't really a fast-path for us), so material for -next. 0f0e134 drm/i915: Hold gt_lock during reset I still don't see what race you're trying to protect here, after all the gpu just died, things are confusing anyway (and anyone accessing the gpu in such a state should take that into account). Currently that's no one afaics. So imo at most -next material. 176b987 drm/i915: Move reset forcewake processing to gen6_do_reset Again this is imo just a cleanup. Furthermore the commit msg is lying a bit because it fails to mention the fix to use the forcewake function pointer. So the cleanup is imo for -next and the bugfix is really old, see: > > -- > keith.packard@intel.com -- Daniel Vetter Mail: daniel@ffwll.ch Mobile: +41 (0)79 365 57 48