From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH] drm/i915: unconditionally use mt forcewake on hsw/ivb Date: Fri, 19 Oct 2012 09:39:59 -0700 Message-ID: <20121019093959.0362cec2@jbarnes-desktop> References: <1350564275-27885-1-git-send-email-daniel.vetter@ffwll.ch> 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 6EC809E747 for ; Fri, 19 Oct 2012 09:39:10 -0700 (PDT) In-Reply-To: <1350564275-27885-1-git-send-email-daniel.vetter@ffwll.ch> 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: Daniel Vetter Cc: Intel Graphics Development List-Id: intel-gfx@lists.freedesktop.org On Thu, 18 Oct 2012 14:44:35 +0200 Daniel Vetter wrote: > Single-threaded forcewake was only used on some early pre-production > ivybridge machines, all the latest ones should use mt forcewake. And > we already assume this in other places of the code (e.g. DERRMR > support in the ddx, or the latest intel_gt_reset patch to reset any > lingering forcewake references left behind by the bios), so don't > bother here, too. > > Signed-off-by: Daniel Vetter > --- > drivers/gpu/drm/i915/intel_pm.c | 31 ++++--------------------------- > 1 file changed, 4 insertions(+), 27 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c > index 2b3cddf..568c98d 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -4146,35 +4146,12 @@ void intel_gt_init(struct drm_device *dev) > if (IS_VALLEYVIEW(dev)) { > dev_priv->gt.force_wake_get = vlv_force_wake_get; > dev_priv->gt.force_wake_put = vlv_force_wake_put; > - } else if (INTEL_INFO(dev)->gen >= 6) { > + } else if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) { > + dev_priv->gt.force_wake_get = __gen6_gt_force_wake_mt_get; > + dev_priv->gt.force_wake_put = __gen6_gt_force_wake_mt_put; > + } else if (IS_GEN6(dev)) { > dev_priv->gt.force_wake_get = __gen6_gt_force_wake_get; > dev_priv->gt.force_wake_put = __gen6_gt_force_wake_put; > - > - /* IVB configs may use multi-threaded forcewake */ > - if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) { > - u32 ecobus; > - > - /* A small trick here - if the bios hasn't configured > - * MT forcewake, and if the device is in RC6, then > - * force_wake_mt_get will not wake the device and the > - * ECOBUS read will return zero. Which will be > - * (correctly) interpreted by the test below as MT > - * forcewake being disabled. > - */ > - mutex_lock(&dev->struct_mutex); > - __gen6_gt_force_wake_mt_get(dev_priv); > - ecobus = I915_READ_NOTRACE(ECOBUS); > - __gen6_gt_force_wake_mt_put(dev_priv); > - mutex_unlock(&dev->struct_mutex); > - > - if (ecobus & FORCEWAKE_MT_ENABLE) { > - DRM_DEBUG_KMS("Using MT version of forcewake\n"); > - dev_priv->gt.force_wake_get = > - __gen6_gt_force_wake_mt_get; > - dev_priv->gt.force_wake_put = > - __gen6_gt_force_wake_mt_put; > - } > - } > } > } > Reviewed-by: Jesse Barnes Pretty sure it was just early, pre-production IVB that didn't use MT, so this should be safe. -- Jesse Barnes, Intel Open Source Technology Center