Re: [PATCH 6/8] drm/i915: Disable planes more atomically during modesets

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

On Fri, Mar 01, 2024 at 04:35:58PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Follow in the footsteps of commit c610e841f19d ("drm/i915:
> Do plane/etc. updates more atomically across pipes") and
> do the plane disables back to back for all pipes also when
> we are disabling pipes.
> 
> This should provide for a potentially more atomic user
> experience, which might be especially nice when using
> joiner or tiled displays.

Okay, so the difference is that previously we did call 
intel_pre_plane_update/intel_crtc_disable_planes per crtc, but
now we first call first intel_pre_plane_update for each crtc
and then call intel_crtc_disable_planes per crtc.

So in cases when there are some cross pipe dependencies, that might be
more proper way. Just to clarify that I understood this right.

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 | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 2351ee52d16e..01d7e91cb1bc 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -6795,11 +6795,16 @@ static void intel_commit_modeset_disables(struct intel_atomic_state *state)
>  		if (!old_crtc_state->hw.active)
>  			continue;
>  
> -		intel_crtc_disable_planes(state, crtc);
> -
>  		disable_pipes |= BIT(crtc->pipe);
>  	}
>  
> +	for_each_old_intel_crtc_in_state(state, crtc, old_crtc_state, i) {
> +		if ((disable_pipes & BIT(crtc->pipe)) == 0)
> +			continue;
> +
> +		intel_crtc_disable_planes(state, crtc);
> +	}
> +
>  	/* Only disable port sync and MST slaves */
>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>  					    new_crtc_state, i) {
> -- 
> 2.43.0
>