[Intel-gfx] [PATCH 1/3] drm/atomic-helper: Add option to update planes only on active crtc

[Maarten Lankhorst]

Op 29-07-15 om 14:01 schreef Daniel Vetter:
> With drivers supporting runtime pm it's generally not a good idea to
> touch the hardware when it's off. Add an option to the commit_planes
> helper to support this case.
>
> Note that the helpers already add all planes on a crtc when a modeset
> happens, hence plane updates will not be lost if drivers set this to
> true.
>
> v2: Check for NULL state->crtc before chasing the pointer. Also check
> both old and new crtc if there's a switch. Finally just outright
> disallow switching crtcs for a plane if the plane is in active use, on
> most hardware that doesn't make sense.
>
> v3: Since commit_planes(active_only = true) is for enabling things
> only after all the crtc are on we should only look at the new crtc to
> decide whether to call the plane hooks - if the current CRTC isn't on
> then skip. If the old crtc (when moving a plane) went down then the
> plane should have been disabled as part of the pipe shutdown work
> already. For which there's currently no helper really unfortunately.
> Also move the check for wether a plane gets a new CRTC assigned while
> still in active use out of this patch.
>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Cc: Thierry Reding <treding at nvidia.com>
> Cc: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> ---
>  drivers/gpu/drm/drm_atomic_helper.c    | 20 ++++++++++++++++++--
>  drivers/gpu/drm/exynos/exynos_drm_fb.c |  2 +-
>  drivers/gpu/drm/msm/msm_atomic.c       |  2 +-
>  drivers/gpu/drm/omapdrm/omap_drv.c     |  2 +-
>  drivers/gpu/drm/rcar-du/rcar_du_kms.c  |  2 +-
>  drivers/gpu/drm/sti/sti_drm_drv.c      |  2 +-
>  drivers/gpu/drm/tegra/drm.c            |  2 +-
>  include/drm/drm_atomic_helper.h        |  3 ++-
>  8 files changed, 26 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 0b475fae067d..6be0adb5a0e9 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -1029,7 +1029,7 @@ int drm_atomic_helper_commit(struct drm_device *dev,
>  
>  	drm_atomic_helper_commit_modeset_disables(dev, state);
>  
> -	drm_atomic_helper_commit_planes(dev, state);
> +	drm_atomic_helper_commit_planes(dev, state, false);
>  
>  	drm_atomic_helper_commit_modeset_enables(dev, state);
>  
> @@ -1144,10 +1144,16 @@ fail:
>  }
>  EXPORT_SYMBOL(drm_atomic_helper_prepare_planes);
>  
> +bool plane_crtc_active(struct drm_plane_state *state)
> +{
> +	return state->crtc && state->crtc->state->active;
> +}
> +
>  /**
>   * drm_atomic_helper_commit_planes - commit plane state
>   * @dev: DRM device
>   * @old_state: atomic state object with old state structures
> + * @active_only: Only commit on active CRTC if set
>   *
>   * This function commits the new plane state using the plane and atomic helper
>   * functions for planes and crtcs. It assumes that the atomic state has already
> @@ -1162,7 +1168,8 @@ EXPORT_SYMBOL(drm_atomic_helper_prepare_planes);
>   * drm_atomic_helper_commit_planes_on_crtc() instead.
>   */
>  void drm_atomic_helper_commit_planes(struct drm_device *dev,
> -				     struct drm_atomic_state *old_state)
> +				     struct drm_atomic_state *old_state,
> +				     bool active_only)
>  {
>  	struct drm_crtc *crtc;
>  	struct drm_crtc_state *old_crtc_state;
> @@ -1178,6 +1185,9 @@ void drm_atomic_helper_commit_planes(struct drm_device *dev,
>  		if (!funcs || !funcs->atomic_begin)
>  			continue;
>  
> +		if (active_only && !crtc->state->active)
> +			continue;
> +
>  		funcs->atomic_begin(crtc, old_crtc_state);
>  	}
>  
> @@ -1189,6 +1199,9 @@ void drm_atomic_helper_commit_planes(struct drm_device *dev,
>  		if (!funcs)
>  			continue;
>  
> +		if (active_only && !plane_crtc_active(plane->state))
> +			continue;
> +
>  		/*
>  		 * Special-case disabling the plane if drivers support it.
>  		 */
>
This would leave a plane active if it was moved from a active crtc to a inactive crtc, you would still need to call the atomic_disable(plane) callback for that one. ;-)

~Maarten