> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Ville
> Syrjala
> Sent: Wednesday, December 13, 2023 3:55 PM
> To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Subject: [PATCH 6/9] drm/i915: Move the min/max scanline sanity check into
> intel_vblank_evade()
>
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> There isn't really any reason to make the caller suffer through checking the vblank
> evasion min/max scanlines. If we somehow ended up with bogus values (which
> really shouldn't happen) then just skip the actual vblank evasion loop but
> otherwise plow ahead as normal.
>
> The only "real" change is that we now get+put a vblank reference even if the
> min/max values are bogus, previously we skipped directly to the end.
Looks fine to me.
Reviewed-by: Uma Shankar <uma.shankar@xxxxxxxxx>
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_crtc.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c
> b/drivers/gpu/drm/i915/display/intel_crtc.c
> index 26a07b2219bf..11a6a4b0a258 100644
> --- a/drivers/gpu/drm/i915/display/intel_crtc.c
> +++ b/drivers/gpu/drm/i915/display/intel_crtc.c
> @@ -544,6 +544,9 @@ static int intel_vblank_evade(struct
> intel_vblank_evade_ctx *evade)
> DEFINE_WAIT(wait);
> int scanline;
>
> + if (evade->min <= 0 || evade->max <= 0)
> + return 0;
> +
> for (;;) {
> /*
> * prepare_to_wait() has a memory barrier, which guarantees
> @@ -633,8 +636,6 @@ void intel_pipe_update_start(struct intel_atomic_state
> *state,
> intel_crtc_vblank_work_init(new_crtc_state);
>
> intel_vblank_evade_init(old_crtc_state, new_crtc_state, &evade);
> - if (evade.min <= 0 || evade.max <= 0)
> - goto irq_disable;
>
> if (drm_WARN_ON(&dev_priv->drm, drm_crtc_vblank_get(&crtc-
> >base)))
> goto irq_disable;
> --
> 2.41.0
