[PATCH 2/2] drm/omap: Normalize the zpos and use the normalized_zpos in runtime

[Daniel Vetter]

On Thu, Dec 21, 2017 at 02:11:01PM +0200, Peter Ujfalusi wrote:
> To avoid zpos collision, use the normalized_zpos when configuring the
> zorder of the plane.
> 
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
> ---
>  drivers/gpu/drm/omapdrm/omap_drv.c   | 26 +++++++++++++++++++++++++-
>  drivers/gpu/drm/omapdrm/omap_plane.c |  2 +-
>  2 files changed, 26 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c
> index 6bfc2d9ebb46..230df6d8edd1 100644
> --- a/drivers/gpu/drm/omapdrm/omap_drv.c
> +++ b/drivers/gpu/drm/omapdrm/omap_drv.c
> @@ -21,6 +21,7 @@
>  
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_blend.h>
>  #include <drm/drm_crtc_helper.h>
>  #include <drm/drm_fb_helper.h>
>  
> @@ -54,6 +55,29 @@ MODULE_PARM_DESC(displays,
>   *                 devices
>   */
>  
> +int omap_atomic_helper_check(struct drm_device *dev,
> +			     struct drm_atomic_state *state)
> +{
> +	int ret;
> +
> +	ret = drm_atomic_helper_check_modeset(dev, state);
> +	if (ret)
> +		return ret;
> +
> +	ret = drm_atomic_normalize_zpos(dev, state);
> +	if (ret)
> +		return ret;

Maybe we should call this by default from helpers instead of forcing
everyone to reinvent this particular wheel?

exynos and sti have the exact same code as you do here, ans rcar could
also reuse it. That feels like we should just fix up
drm_atomic_helper_check instead of patching all the drivers. And as long
as you never change zpos it shouldn't ever run.
-Daniel

> +
> +	ret = drm_atomic_helper_check_planes(dev, state);
> +	if (ret)
> +		return ret;
> +
> +	if (state->legacy_cursor_update)
> +		state->async_update = !drm_atomic_helper_async_check(dev, state);
> +
> +	return ret;
> +}
> +
>  static void omap_atomic_wait_for_completion(struct drm_device *dev,
>  					    struct drm_atomic_state *old_state)
>  {
> @@ -133,7 +157,7 @@ static const struct drm_mode_config_helper_funcs omap_mode_config_helper_funcs =
>  static const struct drm_mode_config_funcs omap_mode_config_funcs = {
>  	.fb_create = omap_framebuffer_create,
>  	.output_poll_changed = drm_fb_helper_output_poll_changed,
> -	.atomic_check = drm_atomic_helper_check,
> +	.atomic_check = omap_atomic_helper_check,
>  	.atomic_commit = drm_atomic_helper_commit,
>  };
>  
> diff --git a/drivers/gpu/drm/omapdrm/omap_plane.c b/drivers/gpu/drm/omapdrm/omap_plane.c
> index bbbdd560e503..abd78b511e6d 100644
> --- a/drivers/gpu/drm/omapdrm/omap_plane.c
> +++ b/drivers/gpu/drm/omapdrm/omap_plane.c
> @@ -65,7 +65,7 @@ static void omap_plane_atomic_update(struct drm_plane *plane,
>  	info.rotation_type = OMAP_DSS_ROT_NONE;
>  	info.rotation = DRM_MODE_ROTATE_0;
>  	info.global_alpha = 0xff;
> -	info.zorder = state->zpos;
> +	info.zorder = state->normalized_zpos;
>  
>  	/* update scanout: */
>  	omap_framebuffer_update_scanout(state->fb, state, &info);
> -- 
> Peter
> 
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch