Instead of waiting for 50ms, just wait until the next vblank, since it's the minimum requirement. This moves PC7 residency on my specific BDW machine running Cinnamon from 60-70% to 84-89%. Without FBC, I get 20-25%. I'm using a 3200x1800 eDP panel. Signed-off-by: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_drv.h | 2 +- drivers/gpu/drm/i915/intel_fbc.c | 12 +++--------- 2 files changed, 4 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index fdbe068..784ce2e 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -918,9 +918,9 @@ struct i915_fbc { struct intel_fbc_work { bool scheduled; + u32 scheduled_vblank; struct work_struct work; struct drm_framebuffer *fb; - unsigned long enable_jiffies; } work; const char *no_fbc_reason; diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index a7192dd..cbdf2f3 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -448,7 +448,6 @@ static void intel_fbc_work_fn(struct work_struct *__work) container_of(__work, struct drm_i915_private, fbc.work.work); struct intel_fbc_work *work = &dev_priv->fbc.work; struct intel_crtc *crtc = dev_priv->fbc.crtc; - unsigned long delay_jiffies = msecs_to_jiffies(50); retry: /* Delay the actual enabling to let pageflipping cease and the @@ -457,14 +456,9 @@ retry: * vblank to pass after disabling the FBC before we attempt * to modify the control registers. * - * A more complicated solution would involve tracking vblanks - * following the termination of the page-flipping sequence - * and indeed performing the enable as a co-routine and not - * waiting synchronously upon the vblank. - * * WaFbcWaitForVBlankBeforeEnable:ilk,snb */ - wait_remaining_ms_from_jiffies(work->enable_jiffies, delay_jiffies); + intel_wait_for_vblank(dev_priv->dev, crtc->pipe); mutex_lock(&dev_priv->fbc.lock); @@ -473,7 +467,7 @@ retry: goto out; /* Were we delayed again while this function was sleeping? */ - if (time_after(work->enable_jiffies + delay_jiffies, jiffies)) { + if (drm_crtc_vblank_get(&crtc->base) == work->scheduled_vblank) { mutex_unlock(&dev_priv->fbc.lock); goto retry; } @@ -506,7 +500,7 @@ static void intel_fbc_schedule_activation(struct intel_crtc *crtc) * jiffy count. */ work->fb = crtc->base.primary->fb; work->scheduled = true; - work->enable_jiffies = jiffies; + work->scheduled_vblank = drm_crtc_vblank_count(&crtc->base); schedule_work(&work->work); } -- 2.6.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx