On Wed, Sep 30, 2015 at 02:29:49PM +0200, Vincent Abriou wrote:

Drivers with software vblank counter relies on the on drm core to update vblank counter and they should not be concern about the warning that check hardware counter coherency.

Further, the generic message that tracks the current and last counter values must be counter type (hardware or software) agnostic.

Cc: Ville Syrj?l? ville.syrjala@linux.intel.com Signed-off-by: Vincent Abriou vincent.abriou@st.com

I sent a patch to get rid of the drm_vblank_count() abuse in all drivers. That will get rid of the WARN too.

---

drivers/gpu/drm/drm_irq.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 88fbee4..88041b4 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -219,11 +219,12 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, } else { /* some kind of default for drivers w/o accurate vbl timestamping */ diff = (flags & DRM_CALLED_FROM_VBLIRQ) != 0;

• if (diff == 0)
  

• 	return;
  

  }

• DRM_DEBUG("updating vblank count on crtc %u:"

•   " current=%u, diff=%u, hw=%u hw_last=%u\n",
  

•   pipe, vblank->count, diff, cur_vblank, vblank->last);
  

• DRM_DEBUG("updating vblank count on crtc %u: diff=%u cur=%u last=%u\n",

•   pipe, diff, cur_vblank, vblank->last);
  
  

  if (diff == 0) { WARN_ON_ONCE(cur_vblank != vblank->last);

-- 1.9.1