[Intel-gfx] [PATCH 11/12] drm/i915: Assert that VRR is off during vblank evasion if necessary

[Manasi Navare]

Reviewed-by: Manasi Navare <navaremanasi at chromium.org>

Manasi

On Fri, Sep 1, 2023 at 6:05 AM Ville Syrjala
<ville.syrjala at linux.intel.com> wrote:
>
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
> Whenever we change the actual transcoder timings (clock via
> seamless M/N, full modeset, (or soon) vtotal via LRR) we
> want the timing generator to be in non-VRR during the commit.
> Warn if we forgot to turn VRR off prior to vblank evasion.
>
> Cc: Manasi Navare <navaremanasi at chromium.org>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_crtc.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
> index a04076064f02..a39e31c1ca85 100644
> --- a/drivers/gpu/drm/i915/display/intel_crtc.c
> +++ b/drivers/gpu/drm/i915/display/intel_crtc.c
> @@ -493,6 +493,10 @@ static void intel_crtc_vblank_evade_scanlines(struct intel_atomic_state *state,
>         adjusted_mode = &crtc_state->hw.adjusted_mode;
>
>         if (crtc->mode_flags & I915_MODE_FLAG_VRR) {
> +               /* timing changes should happen with VRR disabled */
> +               drm_WARN_ON(state->base.dev, intel_crtc_needs_modeset(new_crtc_state) ||
> +                           new_crtc_state->update_m_n);
> +
>                 if (intel_vrr_is_push_sent(crtc_state))
>                         *vblank_start = intel_vrr_vmin_vblank_start(crtc_state);
>                 else
> --
> 2.41.0
>