| Message ID | 1450110229-30450-7-git-send-email-ville.syrjala@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Dec 14, 2015 at 06:23:45PM +0200, ville.syrjala@linux.intel.com wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Since > commit 4dfd648 ("drm: Use vblank timestamps to guesstimate how many vblanks were missed") > the vblank code can cook up a frame counter value based on > the vblank timestamps (as long as they're accurate), so there's > no longer any need to keep vblank interrupts enabled on gen2 > when no one is interested in them. So let's opt into the > immediate disable scheme on gen2 as well. > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Yeah makes sense. Userspace that cares can simply ask for a vblank event in 1000 frames or so, to keep the vblank interrupt enabled. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > --- > drivers/gpu/drm/i915/i915_irq.c | 9 +-------- > 1 file changed, 1 insertion(+), 8 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > index 37ec8427359a..111edda1e73d 100644 > --- a/drivers/gpu/drm/i915/i915_irq.c > +++ b/drivers/gpu/drm/i915/i915_irq.c > @@ -4437,14 +4437,7 @@ void intel_irq_init(struct drm_i915_private *dev_priv) > dev->max_vblank_count = 0xffffff; /* only 24 bits of frame count */ > } > > - /* > - * Opt out of the vblank disable timer on everything except gen2. > - * Gen2 doesn't have a hardware frame counter and so depends on > - * vblank interrupts to produce sane vblank seuquence numbers. > - */ > - if (!IS_GEN2(dev_priv)) > - dev->vblank_disable_immediate = true; > - > + dev->vblank_disable_immediate = true; > dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp; > dev->driver->get_scanout_position = i915_get_crtc_scanoutpos; > > -- > 2.4.10 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
On Wed, Dec 16, 2015 at 11:31:31AM +0100, Daniel Vetter wrote: > On Mon, Dec 14, 2015 at 06:23:45PM +0200, ville.syrjala@linux.intel.com wrote: > > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > > Since > > commit 4dfd648 ("drm: Use vblank timestamps to guesstimate how many vblanks were missed") > > the vblank code can cook up a frame counter value based on > > the vblank timestamps (as long as they're accurate), so there's > > no longer any need to keep vblank interrupts enabled on gen2 > > when no one is interested in them. So let's opt into the > > immediate disable scheme on gen2 as well. > > > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Yeah makes sense. Userspace that cares can simply ask for a vblank event > in 1000 frames or so, to keep the vblank interrupt enabled. I prefer my don't do immediate_disable until after we finish the vblank event. I have vblank/flip keepalives in userspace - but at the end of the day they just add work when we can make a change in the kernel to reduce work. -Chris
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 37ec8427359a..111edda1e73d 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -4437,14 +4437,7 @@ void intel_irq_init(struct drm_i915_private *dev_priv) dev->max_vblank_count = 0xffffff; /* only 24 bits of frame count */ } - /* - * Opt out of the vblank disable timer on everything except gen2. - * Gen2 doesn't have a hardware frame counter and so depends on - * vblank interrupts to produce sane vblank seuquence numbers. - */ - if (!IS_GEN2(dev_priv)) - dev->vblank_disable_immediate = true; - + dev->vblank_disable_immediate = true; dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp; dev->driver->get_scanout_position = i915_get_crtc_scanoutpos;