| Message ID | 1383753389-12763-4-git-send-email-rodrigo.vivi@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 2013-11-06 at 13:56 -0200, Rodrigo Vivi wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > When the hardware frame counter reads 0xffffff and we're already past > vblank start, we'd return 0x1000000 as the vblank counter value. Once > we'd cross into the next frame's active portion, the vblank counter > would wrap to 0. So we're reporting two different vblank counter values > for the same frame. > > Fix the problem by masking the cooked value by 0xffffff to make sure > the counter wraps already after vblank start. > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> Reviewed-by: Imre Deak <imre.deak@intel.com> > --- > drivers/gpu/drm/i915/i915_irq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > index 2a44816..c474dac 100644 > --- a/drivers/gpu/drm/i915/i915_irq.c > +++ b/drivers/gpu/drm/i915/i915_irq.c > @@ -583,7 +583,7 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, int pipe) > * Cook up a vblank counter by also checking the pixel > * counter against vblank start. > */ > - return ((high1 << 8) | low) + (pixel >= vbl_start); > + return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff; > } > > static u32 gm45_get_vblank_counter(struct drm_device *dev, int pipe)
On Thu, Nov 07, 2013 at 06:16:47PM +0200, Imre Deak wrote: > On Wed, 2013-11-06 at 13:56 -0200, Rodrigo Vivi wrote: > > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > > When the hardware frame counter reads 0xffffff and we're already past > > vblank start, we'd return 0x1000000 as the vblank counter value. Once > > we'd cross into the next frame's active portion, the vblank counter > > would wrap to 0. So we're reporting two different vblank counter values > > for the same frame. > > > > Fix the problem by masking the cooked value by 0xffffff to make sure > > the counter wraps already after vblank start. > > > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> > > Reviewed-by: Imre Deak <imre.deak@intel.com> Queued for -next, thanks for the patch. -Daniel
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 2a44816..c474dac 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -583,7 +583,7 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, int pipe) * Cook up a vblank counter by also checking the pixel * counter against vblank start. */ - return ((high1 << 8) | low) + (pixel >= vbl_start); + return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff; } static u32 gm45_get_vblank_counter(struct drm_device *dev, int pipe)