From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: [PATCH 2/4] drm/i915: Restore the display config after a GPU reset on gen4 Date: Tue, 20 May 2014 11:46:42 +0300 Message-ID: <20140520084642.GE27580@intel.com> References: <1400527521-3454-1-git-send-email-ville.syrjala@linux.intel.com> <1400527521-3454-3-git-send-email-ville.syrjala@linux.intel.com> <20140520080344.GD8790@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 1EAAA6E12F for ; Tue, 20 May 2014 01:47:13 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20140520080344.GD8790@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Daniel Vetter Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, May 20, 2014 at 10:03:44AM +0200, Daniel Vetter wrote: > On Mon, May 19, 2014 at 10:25:19PM +0300, ville.syrjala@linux.intel.com w= rote: > > From: Ville Syrj=E4l=E4 > > = > > On pre-ctg GPU reset also resets the display hardware. Force a mode > > restore after the GPU reset, and also re-init clock gating. > > = > > Signed-off-by: Ville Syrj=E4l=E4 > > --- > > drivers/gpu/drm/i915/i915_drv.c | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > = > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i91= 5_drv.c > > index b948c71..2ec3796 100644 > > --- a/drivers/gpu/drm/i915/i915_drv.c > > +++ b/drivers/gpu/drm/i915/i915_drv.c > > @@ -794,6 +794,14 @@ int i915_reset(struct drm_device *dev) > > if (INTEL_INFO(dev)->gen > 5) > > intel_reset_gt_powersave(dev); > > = > > + if (IS_GEN4(dev) && !IS_G4X(dev)) { > > + intel_init_clock_gating(dev); > > + > > + drm_modeset_lock_all(dev); > > + intel_modeset_setup_hw_state(dev, true); > > + drm_modeset_unlock_all(dev); > = > Locking inversion here. I think we need to push this down to the very end. We already dropped struct_mutex a bit earlier. Or was there some other lock you were worried about? > Also this leaves the interesting question of what happens with vblank > waits and friends ... Hmm. I guess we might have some kind of refcount problem on our hands w/ vblanks and whatnot. Might be I'd need to for_each_crtc() .crtc_disable() before the reset. That would match the g33 spec's recommendation to disable all planes, but it also does quite a bit more, maybe too much? But I could try it at least. -- = Ville Syrj=E4l=E4 Intel OTC