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

["Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com>]

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.golani@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