Re: [PATCH v8 13/18] drm/i915/display: Wait for VRR PUSH status update

[Nautiyal, Ankit K]

On 11/17/2025 11:14 AM, Mitul Golani wrote:
After VRR Push is sent, need to wait till flipline decision boundary
to get Push bit to get cleared.

--v2:
- Adjust delays to vrr vmin vblank delays. (Ankit)

Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.gol...@intel.com>
---
  drivers/gpu/drm/i915/display/intel_vrr.c | 30 ++++++++++++++++++++++--
  1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c 
b/drivers/gpu/drm/i915/display/intel_vrr.c
index 7634d6a7ccaf..315d0e4ef43d 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -160,14 +160,40 @@ int intel_vrr_vmax_vtotal(const struct intel_crtc_state 
*crtc_state)
        return crtc_state->vrr.vmax;
  }
  
+static int
+intel_vrr_dcb_vmin_vblank_start(const struct intel_crtc_state *crtc_state)
+{
+       return (intel_vrr_dcb_vmin_vblank_start_next(crtc_state) < 0) ?
+               intel_vrr_dcb_vmin_vblank_start_final(crtc_state) :
+               intel_vrr_dcb_vmin_vblank_start_next(crtc_state);
+}
+
  int intel_vrr_vmin_vblank_start(const struct intel_crtc_state *crtc_state)
  {
-       return intel_vrr_vmin_vtotal(crtc_state) - crtc_state->vrr.guardband;
+       if (crtc_state->vrr.dc_balance.enable) {
+               return (intel_vrr_dcb_vmin_vblank_start(crtc_state) -
+                       crtc_state->vrr.guardband);

This seems to be wrong.

intel_vrr_dcb_vmin/vmax_vblank_start() is vblank_start. Guardband is 
already subtracted from Vmin/Vmax to get the vblank_start. We do not 
need to subtract guardband again.

Also, lets not change intel_vrr_vmin/vmax_vblank_start(). Use the dcb 
versions in place where dcb is enabled, similar to Patch#12.

I think you need to change intel_vrr_vmin_safe_window_end() so that 
intel_dsb_wait_for_delayed_vblank() uses correct delay when dcb is in 
picture.


Regards,

Ankit


+       } else {
+               return intel_vrr_vmin_vtotal(crtc_state) - 
crtc_state->vrr.guardband;
+       }
+}
+
+static int
+intel_vrr_dcb_vmax_vblank_start(const struct intel_crtc_state *crtc_state)
+{
+       return (intel_vrr_dcb_vmax_vblank_start_next(crtc_state) < 0) ?
+               intel_vrr_dcb_vmax_vblank_start_final(crtc_state) :
+               intel_vrr_dcb_vmax_vblank_start_next(crtc_state);
  }
  
  int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state)
  {
-       return intel_vrr_vmax_vtotal(crtc_state) - crtc_state->vrr.guardband;
+       if (crtc_state->vrr.dc_balance.enable) {
+               return (intel_vrr_dcb_vmax_vblank_start(crtc_state) -
+                       crtc_state->vrr.guardband);
+       } else {
+               return intel_vrr_vmax_vtotal(crtc_state) - 
crtc_state->vrr.guardband;
+       }
  }
  
  static bool