[PATCH 01/14] drm/i915: Calculate vblank delay more accurately

[Manna, Animesh]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Ville
> Syrjala
> Sent: Tuesday, June 25, 2024 12:40 AM
> To: intel-gfx at lists.freedesktop.org
> Subject: [PATCH 01/14] drm/i915: Calculate vblank delay more accurately
> 
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Calculate the vblank delay in the vblank evasion code correctly for interlaced
> modes.
> 
> The current code assumes that we won't be using an interlaced mode.
> That assumption is actually valid since we've defeatured interlaced scanout
> in commit f71c9b7bc35f ("drm/i915/display: Prune Interlace modes for
> Display >=12") for DSB capable platforms. However the feature is still present
> in the hardware, and if we ever find the need to re-enable it seems better to
> calculate the vblank delay correctly.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

LGTM.
Reviewed-by: Animesh Manna <animesh.manna at intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_vblank.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_vblank.c
> b/drivers/gpu/drm/i915/display/intel_vblank.c
> index 5b065e1cd4e4..f183e0d4b2ba 100644
> --- a/drivers/gpu/drm/i915/display/intel_vblank.c
> +++ b/drivers/gpu/drm/i915/display/intel_vblank.c
> @@ -652,7 +652,8 @@ void intel_vblank_evade_init(const struct
> intel_crtc_state *old_crtc_state,
>  	 */
>  	if (intel_color_uses_dsb(new_crtc_state) ||
>  	    new_crtc_state->update_m_n || new_crtc_state->update_lrr)
> -		evade->min -= adjusted_mode->crtc_vblank_start -
> adjusted_mode->crtc_vdisplay;
> +		evade->min -= intel_mode_vblank_start(adjusted_mode) -
> +			intel_mode_vdisplay(adjusted_mode);
>  }
> 
>  /* must be called with vblank interrupt already enabled! */
> --
> 2.44.2