On Wed, Apr 30, 2014 at 10:07:02AM -0700, Matt Roper wrote:
> In a future patch, we'll allow the primary plane to be disabled by
> userspace via the universal plane API.  If a modeset is requested while
> the primary plane is disabled, crtc->primary->fb will be NULL which
> generally triggers a full modeset (except in fastboot situations).  If
> we detect that the crtc is active, but there's no primary plane fb,
> we should still allow a simple plane update rather than a full modeset
> if the mode isn't actually changing (after re-enabling the primary plane
> of course).
> 
> Signed-off-by: Matt Roper <matthew.d.ro...@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 22 ++++++++++++++++++++--
>  1 file changed, 20 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c 
> b/drivers/gpu/drm/i915/intel_display.c
> index e1e1239..04bd821 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -10136,12 +10136,17 @@ intel_set_config_compute_mode_changes(struct 
> drm_mode_set *set,
>       if (is_crtc_connector_off(set)) {
>               config->mode_changed = true;
>       } else if (set->crtc->primary->fb != set->fb) {
> -             /* If we have no fb then treat it as a full mode set */
> +             /*
> +              * If we have no fb, we can only flip as long as the crtc is
> +              * active, otherwise we need a full mode set.  The crtc may
> +              * be active if we've only disabled the primary plane, or
> +              * in fastboot situations.
> +              */
>               if (set->crtc->primary->fb == NULL) {
>                       struct intel_crtc *intel_crtc =
>                               to_intel_crtc(set->crtc);
>  
> -                     if (intel_crtc->active && i915.fastboot) {
> +                     if (intel_crtc->active) {
>                               DRM_DEBUG_KMS("crtc has no fb, will flip\n");
>                               config->fb_changed = true;
>                       } else {
> @@ -10380,8 +10385,21 @@ static int intel_crtc_set_config(struct drm_mode_set 
> *set)
>               ret = intel_set_mode(set->crtc, set->mode,
>                                    set->x, set->y, set->fb);
>       } else if (config->fb_changed) {
> +             struct drm_i915_private *dev_priv = dev->dev_private;
> +             struct intel_crtc *intel_crtc = to_intel_crtc(set->crtc);
> +
>               intel_crtc_wait_for_pending_flips(set->crtc);
>  
> +             /*
> +              * We need to make sure the primary plane is re-enabled if it
> +              * has previously been turned off.
> +              */
> +             if (!intel_crtc->primary_enabled) {
> +                     BUG_ON(!intel_crtc->active);

BUG seems a bit harsh.

> +                     intel_enable_primary_hw_plane(dev_priv, 
> intel_crtc->plane,
> +                                                   intel_crtc->pipe);
> +             }
> +
>               ret = intel_pipe_set_base(set->crtc,
>                                         set->x, set->y, set->fb);

Enable the plane after set_base to avoid lighting up the plane if
set_base fails, and it'll also make the flip+enable atomic and so
we avoid flashing the old fb at the user.

>               /*
> -- 
> 1.8.5.1
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to