Re: [PATCH 5/8] drm/i915: Precompute disable_pipes bitmask in intel_commit_modeset_disables()

["Lisovskiy, Stanislav" <stanislav.lisovskiy@intel.com>]

On Fri, Mar 01, 2024 at 04:35:57PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Copy the pipe bitmask based approach skl_commit_modeset_enables()
> into intel_commit_modeset_disables(). This avoids doing so many
> duplicated checks in all the loops, and also let's us WARN at the
> end if we screwed up somewhere and forgot to disable some pipe.

Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 27 ++++++++++++--------
>  1 file changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 8cc5de31c1dd..2351ee52d16e 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -6775,9 +6775,10 @@ static void intel_old_crtc_state_disables(struct intel_atomic_state *state,
>  
>  static void intel_commit_modeset_disables(struct intel_atomic_state *state)
>  {
> +	struct drm_i915_private *i915 = to_i915(state->base.dev);
>  	struct intel_crtc_state *new_crtc_state, *old_crtc_state;
>  	struct intel_crtc *crtc;
> -	u32 handled = 0;
> +	u8 disable_pipes = 0;
>  	int i;
>  
>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
> @@ -6785,21 +6786,24 @@ static void intel_commit_modeset_disables(struct intel_atomic_state *state)
>  		if (!intel_crtc_needs_modeset(new_crtc_state))
>  			continue;
>  
> +		/*
> +		 * Needs to be done even for pipes
> +		 * that weren't enabled previously.
> +		 */
>  		intel_pre_plane_update(state, crtc);
>  
>  		if (!old_crtc_state->hw.active)
>  			continue;
>  
>  		intel_crtc_disable_planes(state, crtc);
> +
> +		disable_pipes |= BIT(crtc->pipe);
>  	}
>  
>  	/* Only disable port sync and MST slaves */
>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>  					    new_crtc_state, i) {
> -		if (!intel_crtc_needs_modeset(new_crtc_state))
> -			continue;
> -
> -		if (!old_crtc_state->hw.active)
> +		if ((disable_pipes & BIT(crtc->pipe)) == 0)
>  			continue;
>  
>  		/* In case of Transcoder port Sync master slave CRTCs can be
> @@ -6814,22 +6818,23 @@ static void intel_commit_modeset_disables(struct intel_atomic_state *state)
>  
>  		intel_old_crtc_state_disables(state, old_crtc_state,
>  					      new_crtc_state, crtc);
> -		handled |= BIT(crtc->pipe);
> +
> +		disable_pipes &= ~BIT(crtc->pipe);
>  	}
>  
>  	/* Disable everything else left on */
>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>  					    new_crtc_state, i) {
> -		if (!intel_crtc_needs_modeset(new_crtc_state) ||
> -		    (handled & BIT(crtc->pipe)))
> -			continue;
> -
> -		if (!old_crtc_state->hw.active)
> +		if ((disable_pipes & BIT(crtc->pipe)) == 0)
>  			continue;
>  
>  		intel_old_crtc_state_disables(state, old_crtc_state,
>  					      new_crtc_state, crtc);
> +
> +		disable_pipes &= ~BIT(crtc->pipe);
>  	}
> +
> +	drm_WARN_ON(&i915->drm, disable_pipes);
>  }
>  
>  static void intel_commit_modeset_enables(struct intel_atomic_state *state)
> -- 
> 2.43.0
>