Re: [PATCH v8 18/18] drm/i915/vrr: Add function to check if DC Balance Possible

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

On 11/17/2025 11:14 AM, Mitul Golani wrote:
> Add function to check if DC Balance possibile on
> requested PIPE and also validate along with DISPLAY_VER
> check.
>
> Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
> Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_vrr.c | 20 +++++++++++++++++---
>   1 file changed, 17 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
> index 87945b031a7d..8aba20a50d92 100644
> --- a/drivers/gpu/drm/i915/display/intel_vrr.c
> +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
> @@ -263,11 +263,25 @@ void intel_vrr_compute_cmrr_timings(struct intel_crtc_state *crtc_state)
>   }
>   
>   static
> -void intel_vrr_compute_vrr_timings(struct intel_crtc_state *crtc_state,
> -				   int vmin, int vmax)
> +int intel_vrr_dc_balance_possible(const struct intel_crtc_state *crtc_state)
>   {
>   	struct intel_display *display = to_intel_display(crtc_state);
> +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> +	enum pipe pipe = crtc->pipe;
> +
> +	/*
> +	 * FIXME: Currently Firmware supports DC Balancing on PIPE A
> +	 * and PIPE B. Account those limitation while computing DC
> +	 * Balance parameters.
> +	 */
> +	return (HAS_VRR_DC_BALANCE(display) &&
> +		((pipe == PIPE_A) || (pipe == PIPE_B)));
> +}
>   

As also mentioned in last version, this can be merged with the previous 
patch now.


Regards,

Ankit


> +static
> +void intel_vrr_compute_vrr_timings(struct intel_crtc_state *crtc_state,
> +				   int vmin, int vmax)
> +{
>   	crtc_state->vrr.vmax = vmax;
>   	crtc_state->vrr.vmin = vmin;
>   	crtc_state->vrr.flipline = crtc_state->vrr.vmin;
> @@ -275,7 +289,7 @@ void intel_vrr_compute_vrr_timings(struct intel_crtc_state *crtc_state,
>   	crtc_state->vrr.enable = true;
>   	crtc_state->mode_flags |= I915_MODE_FLAG_VRR;
>   
> -	if (HAS_VRR_DC_BALANCE(display))
> +	if (intel_vrr_dc_balance_possible(crtc_state))
>   		crtc_state->vrr.dc_balance.enable = true;
>   }
>