On Mon, May 26, 2014 at 05:26:48PM +0300, ville.syrjala@linux.intel.com wrote:
From: Ville Syrjälä ville.syrjala@linux.intel.com
Now that the vblank races are plugged, we can opt out of using the vblank disable timer and just let vblank interrupts get disabled immediately when the last reference is dropped.
Gen2 is the exception since it has no hardware frame counter.
Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com
I've forgotten to mention (I think so at least) that I'd like to have a new kms_flip subtest which alternates vblank events with longer hrtimer sleeps and still enables all the precise vblank counter/ts checks we have. That should give us tons of flip-flopping of the vblank counter.
After all videos run at 25fps, so are about the worst case for this (since the enable vblank for the 1 frame vblank wait and the for the pageflip, disabling it each time in between) and we very much don't want to fail this.
Bonus points if you add a 2nd thread which races against the first one for added fun (in a 2nd subtest). -Daniel
drivers/gpu/drm/i915/i915_irq.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 28bae6e..4b2e7af 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -4364,6 +4364,14 @@ void intel_irq_init(struct drm_device *dev) 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))
dev->vblank_disable_immediate = true;- if (drm_core_check_feature(dev, DRIVER_MODESET)) { dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp; dev->driver->get_scanout_position = i915_get_crtc_scanoutpos;
-- 1.8.5.5