[RFC,v5,02/10] drm: Introduce solid fill DRM plane property

  Document and add support for solid_fill property to drm_plane. In
addition, add support for setting and getting the values for solid_fill.

To enable solid fill planes, userspace must assign a property blob to
the "solid_fill" plane property containing the following information:

struct drm_mode_solid_fill {
	u32 version;
	u32 r, g, b;
};

Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
 drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
 include/drm/drm_blend.h                   |  1 +
 include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
 include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
 6 files changed, 154 insertions(+)
  

On 28/07/2023 20:02, Jessica Zhang wrote:
> Document and add support for solid_fill property to drm_plane. In
> addition, add support for setting and getting the values for solid_fill.
> 
> To enable solid fill planes, userspace must assign a property blob to
> the "solid_fill" plane property containing the following information:
> 
> struct drm_mode_solid_fill {
> 	u32 version;
> 	u32 r, g, b;
> };
> 
> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> ---
>   drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>   drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>   drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>   include/drm/drm_blend.h                   |  1 +
>   include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>   include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>   6 files changed, 154 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
> index 01638c51ce0a..86fb876efbe6 100644
> --- a/drivers/gpu/drm/drm_atomic_state_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
> @@ -254,6 +254,11 @@ void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
>   	plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI;
>   	plane_state->pixel_source = DRM_PLANE_PIXEL_SOURCE_FB;
>   
> +	if (plane_state->solid_fill_blob) {
> +		drm_property_blob_put(plane_state->solid_fill_blob);
> +		plane_state->solid_fill_blob = NULL;
> +	}
> +
>   	if (plane->color_encoding_property) {
>   		if (!drm_object_property_get_default_value(&plane->base,
>   							   plane->color_encoding_property,
> @@ -336,6 +341,9 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
>   	if (state->fb)
>   		drm_framebuffer_get(state->fb);
>   
> +	if (state->solid_fill_blob)
> +		drm_property_blob_get(state->solid_fill_blob);
> +
>   	state->fence = NULL;
>   	state->commit = NULL;
>   	state->fb_damage_clips = NULL;
> @@ -385,6 +393,7 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
>   		drm_crtc_commit_put(state->commit);
>   
>   	drm_property_blob_put(state->fb_damage_clips);
> +	drm_property_blob_put(state->solid_fill_blob);
>   }
>   EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
>   
> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> index 454f980e16c9..039686c78c2a 100644
> --- a/drivers/gpu/drm/drm_atomic_uapi.c
> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> @@ -316,6 +316,51 @@ drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
>   }
>   EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
>   
> +static int drm_atomic_set_solid_fill_prop(struct drm_plane_state *state,
> +		struct drm_property_blob *blob)
> +{
> +	int blob_version;
> +
> +	if (blob == state->solid_fill_blob)
> +		return 0;
> +
> +	if (blob) {
> +		struct drm_mode_solid_fill *user_info = (struct drm_mode_solid_fill *)blob->data;
> +
> +		if (blob->length != sizeof(struct drm_mode_solid_fill)) {
> +			drm_dbg_atomic(state->plane->dev,
> +				       "[PLANE:%d:%s] bad solid fill blob length: %zu\n",
> +				       state->plane->base.id, state->plane->name,
> +				       blob->length);
> +			return -EINVAL;
> +		}
> +
> +		blob_version = user_info->version;

I remember that we had versioning for quite some time. However it stroke 
me while reviewing that we do not a way to negotiate supported 
SOLID_FILL versions. However as we now have support for different 
pixel_source properties, maybe we can drop version completely. If at 
some point a driver needs to support different kind of SOLID_FILL 
property (consider v2), we can add new pixel source to the enum.

> +
> +		/* Add more versions if necessary */
> +		if (blob_version == 1) {
> +			state->solid_fill.r = user_info->r;
> +			state->solid_fill.g = user_info->g;
> +			state->solid_fill.b = user_info->b;
> +		} else {
> +			drm_dbg_atomic(state->plane->dev,
> +				       "[PLANE:%d:%s] unsupported solid fill version (version=%d)\n",
> +				       state->plane->base.id, state->plane->name,
> +				       blob_version);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	drm_property_blob_put(state->solid_fill_blob);
> +
> +	if (blob)
> +		state->solid_fill_blob = drm_property_blob_get(blob);
> +	else
> +		state->solid_fill_blob = NULL;
> +
> +	return 0;
> +}
> +
>   static void set_out_fence_for_crtc(struct drm_atomic_state *state,
>   				   struct drm_crtc *crtc, s32 __user *fence_ptr)
>   {
> @@ -546,6 +591,13 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
>   		state->src_h = val;
>   	} else if (property == plane->pixel_source_property) {
>   		state->pixel_source = val;
> +	} else if (property == plane->solid_fill_property) {
> +		struct drm_property_blob *solid_fill = drm_property_lookup_blob(dev, val);
> +
> +		ret = drm_atomic_set_solid_fill_prop(state, solid_fill);
> +		drm_property_blob_put(solid_fill);
> +
> +		return ret;

Bonus point: dropping version from SOLID_FILL would allow us to use 
drm_atomic_replace_property_blob_from_id() here.

>   	} else if (property == plane->alpha_property) {
>   		state->alpha = val;
>   	} else if (property == plane->blend_mode_property) {
> @@ -620,6 +672,9 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
>   		*val = state->src_h;
>   	} else if (property == plane->pixel_source_property) {
>   		*val = state->pixel_source;
> +	} else if (property == plane->solid_fill_property) {
> +		*val = state->solid_fill_blob ?
> +			state->solid_fill_blob->base.id : 0;
>   	} else if (property == plane->alpha_property) {
>   		*val = state->alpha;
>   	} else if (property == plane->blend_mode_property) {
> diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c
> index c500310a3d09..c632dfcd8a9b 100644
> --- a/drivers/gpu/drm/drm_blend.c
> +++ b/drivers/gpu/drm/drm_blend.c
> @@ -200,6 +200,10 @@
>    *	"FB":
>    *		Framebuffer source set by the "FB_ID" property.
>    *
> + * solid_fill:
> + *	solid_fill is set up with drm_plane_create_solid_fill_property(). It
> + *	contains pixel data that drivers can use to fill a plane.
> + *
>    * Note that all the property extensions described here apply either to the
>    * plane or the CRTC (e.g. for the background color, which currently is not
>    * exposed and assumed to be black).
> @@ -700,3 +704,29 @@ int drm_plane_create_pixel_source_property(struct drm_plane *plane,
>   	return 0;
>   }
>   EXPORT_SYMBOL(drm_plane_create_pixel_source_property);
> +
> +/**
> + * drm_plane_create_solid_fill_property - create a new solid_fill property
> + * @plane: drm plane
> + *
> + * This creates a new property blob that holds pixel data for solid fill planes.
> + * The property is exposed to userspace as a property blob called "solid_fill".
> + *
> + * For information on what the blob contains, see `drm_mode_solid_fill`.
> + */
> +int drm_plane_create_solid_fill_property(struct drm_plane *plane)
> +{
> +	struct drm_property *prop;
> +
> +	prop = drm_property_create(plane->dev,
> +			DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_BLOB,
> +			"solid_fill", 0);
> +	if (!prop)
> +		return -ENOMEM;
> +
> +	drm_object_attach_property(&plane->base, prop, 0);
> +	plane->solid_fill_property = prop;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(drm_plane_create_solid_fill_property);
> diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h
> index 122bbfbaae33..e7158fbee389 100644
> --- a/include/drm/drm_blend.h
> +++ b/include/drm/drm_blend.h
> @@ -60,4 +60,5 @@ int drm_plane_create_blend_mode_property(struct drm_plane *plane,
>   					 unsigned int supported_modes);
>   int drm_plane_create_pixel_source_property(struct drm_plane *plane,
>   					   unsigned long extra_sources);
> +int drm_plane_create_solid_fill_property(struct drm_plane *plane);
>   #endif
> diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
> index 89508b4dea4a..abf1458fa099 100644
> --- a/include/drm/drm_plane.h
> +++ b/include/drm/drm_plane.h
> @@ -46,6 +46,17 @@ enum drm_plane_pixel_source {
>   	DRM_PLANE_PIXEL_SOURCE_MAX
>   };
>   
> +/**
> + * struct solid_fill_property - RGB values for solid fill plane
> + *
> + * Note: This is the V1 for this feature
> + */
> +struct drm_solid_fill {
> +	uint32_t r;
> +	uint32_t g;
> +	uint32_t b;
> +};
> +
>   /**
>    * struct drm_plane_state - mutable plane state
>    *
> @@ -130,6 +141,23 @@ struct drm_plane_state {
>   	 */
>   	enum drm_plane_pixel_source pixel_source;
>   
> +	/**
> +	 * @solid_fill_blob:
> +	 *
> +	 * Blob containing relevant information for a solid fill plane
> +	 * including pixel format and data. See
> +	 * drm_plane_create_solid_fill_property() for more details.
> +	 */
> +	struct drm_property_blob *solid_fill_blob;
> +
> +	/**
> +	 * @solid_fill:
> +	 *
> +	 * Pixel data for solid fill planes. See
> +	 * drm_plane_create_solid_fill_property() for more details.
> +	 */
> +	struct drm_solid_fill solid_fill;
> +
>   	/**
>   	 * @alpha:
>   	 * Opacity of the plane with 0 as completely transparent and 0xffff as
> @@ -720,6 +748,13 @@ struct drm_plane {
>   	 */
>   	struct drm_property *pixel_source_property;
>   
> +	/**
> +	 * @solid_fill_property:
> +	 * Optional solid_fill property for this plane. See
> +	 * drm_plane_create_solid_fill_property().
> +	 */
> +	struct drm_property *solid_fill_property;
> +
>   	/**
>   	 * @alpha_property:
>   	 * Optional alpha property for this plane. See
> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> index 43691058d28f..53c8efa5ad7f 100644
> --- a/include/uapi/drm/drm_mode.h
> +++ b/include/uapi/drm/drm_mode.h
> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>   	char name[DRM_DISPLAY_MODE_LEN];
>   };
>   
> +/**
> + * struct drm_mode_solid_fill - User info for solid fill planes
> + *
> + * This is the userspace API solid fill information structure.
> + *
> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> + * color and setting the pixel source to "SOLID_FILL".
> + *
> + * For information on the plane property, see drm_plane_create_solid_fill_property()
> + *
> + * @version: Version of the blob. Currently, there is only support for version == 1
> + * @r: Red color value of single pixel
> + * @g: Green color value of single pixel
> + * @b: Blue color value of single pixel
> + */
> +struct drm_mode_solid_fill {
> +	__u32 version;
> +	__u32 r;
> +	__u32 g;
> +	__u32 b;
> +};
> +
> +
>   struct drm_mode_card_res {
>   	__u64 fb_id_ptr;
>   	__u64 crtc_id_ptr;
>
  

On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>
> Document and add support for solid_fill property to drm_plane. In
> addition, add support for setting and getting the values for solid_fill.
>
> To enable solid fill planes, userspace must assign a property blob to
> the "solid_fill" plane property containing the following information:
>
> struct drm_mode_solid_fill {
>         u32 version;
>         u32 r, g, b;
> };
>
> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> ---
>  drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>  drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>  drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>  include/drm/drm_blend.h                   |  1 +
>  include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>  include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>  6 files changed, 154 insertions(+)
>

[skipped most of the patch]

> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> index 43691058d28f..53c8efa5ad7f 100644
> --- a/include/uapi/drm/drm_mode.h
> +++ b/include/uapi/drm/drm_mode.h
> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>         char name[DRM_DISPLAY_MODE_LEN];
>  };
>
> +/**
> + * struct drm_mode_solid_fill - User info for solid fill planes
> + *
> + * This is the userspace API solid fill information structure.
> + *
> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> + * color and setting the pixel source to "SOLID_FILL".
> + *
> + * For information on the plane property, see drm_plane_create_solid_fill_property()
> + *
> + * @version: Version of the blob. Currently, there is only support for version == 1
> + * @r: Red color value of single pixel
> + * @g: Green color value of single pixel
> + * @b: Blue color value of single pixel
> + */
> +struct drm_mode_solid_fill {
> +       __u32 version;
> +       __u32 r;
> +       __u32 g;
> +       __u32 b;

Another thought about the drm_mode_solid_fill uABI. I still think we
should add alpha here. The reason is the following:

It is true that we have  drm_plane_state::alpha and the plane's
"alpha" property. However it is documented as "the plane-wide opacity
[...] It can be combined with pixel alpha. The pixel values in the
framebuffers are expected to not be pre-multiplied by the global alpha
associated to the plane.".

I can imagine a use case, when a user might want to enable plane-wide
opacity, set "pixel blend mode" to "Coverage" and then switch between
partially opaque framebuffer and partially opaque solid-fill without
touching the plane's alpha value.
  

On Mon, Jul 31, 2023 at 6:01 AM Dmitry Baryshkov
<dmitry.baryshkov@linaro.org> wrote:
>
> On 28/07/2023 20:02, Jessica Zhang wrote:
> > Document and add support for solid_fill property to drm_plane. In
> > addition, add support for setting and getting the values for solid_fill.
> >
> > To enable solid fill planes, userspace must assign a property blob to
> > the "solid_fill" plane property containing the following information:
> >
> > struct drm_mode_solid_fill {
> >       u32 version;
> >       u32 r, g, b;
> > };
> >
> > Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> > ---
> >   drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
> >   drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
> >   drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
> >   include/drm/drm_blend.h                   |  1 +
> >   include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
> >   include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
> >   6 files changed, 154 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
> > index 01638c51ce0a..86fb876efbe6 100644
> > --- a/drivers/gpu/drm/drm_atomic_state_helper.c
> > +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
> > @@ -254,6 +254,11 @@ void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
> >       plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI;
> >       plane_state->pixel_source = DRM_PLANE_PIXEL_SOURCE_FB;
> >
> > +     if (plane_state->solid_fill_blob) {
> > +             drm_property_blob_put(plane_state->solid_fill_blob);
> > +             plane_state->solid_fill_blob = NULL;
> > +     }
> > +
> >       if (plane->color_encoding_property) {
> >               if (!drm_object_property_get_default_value(&plane->base,
> >                                                          plane->color_encoding_property,
> > @@ -336,6 +341,9 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
> >       if (state->fb)
> >               drm_framebuffer_get(state->fb);
> >
> > +     if (state->solid_fill_blob)
> > +             drm_property_blob_get(state->solid_fill_blob);
> > +
> >       state->fence = NULL;
> >       state->commit = NULL;
> >       state->fb_damage_clips = NULL;
> > @@ -385,6 +393,7 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
> >               drm_crtc_commit_put(state->commit);
> >
> >       drm_property_blob_put(state->fb_damage_clips);
> > +     drm_property_blob_put(state->solid_fill_blob);
> >   }
> >   EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
> >
> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> > index 454f980e16c9..039686c78c2a 100644
> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> > @@ -316,6 +316,51 @@ drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
> >   }
> >   EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
> >
> > +static int drm_atomic_set_solid_fill_prop(struct drm_plane_state *state,
> > +             struct drm_property_blob *blob)
> > +{
> > +     int blob_version;
> > +
> > +     if (blob == state->solid_fill_blob)
> > +             return 0;
> > +
> > +     if (blob) {
> > +             struct drm_mode_solid_fill *user_info = (struct drm_mode_solid_fill *)blob->data;
> > +
> > +             if (blob->length != sizeof(struct drm_mode_solid_fill)) {
> > +                     drm_dbg_atomic(state->plane->dev,
> > +                                    "[PLANE:%d:%s] bad solid fill blob length: %zu\n",
> > +                                    state->plane->base.id, state->plane->name,
> > +                                    blob->length);
> > +                     return -EINVAL;
> > +             }
> > +
> > +             blob_version = user_info->version;
>
> I remember that we had versioning for quite some time. However it stroke
> me while reviewing that we do not a way to negotiate supported
> SOLID_FILL versions. However as we now have support for different
> pixel_source properties, maybe we can drop version completely. If at
> some point a driver needs to support different kind of SOLID_FILL
> property (consider v2), we can add new pixel source to the enum.

Agreed. Let's drop the versioning.

>
> > +
> > +             /* Add more versions if necessary */
> > +             if (blob_version == 1) {
> > +                     state->solid_fill.r = user_info->r;
> > +                     state->solid_fill.g = user_info->g;
> > +                     state->solid_fill.b = user_info->b;
> > +             } else {
> > +                     drm_dbg_atomic(state->plane->dev,
> > +                                    "[PLANE:%d:%s] unsupported solid fill version (version=%d)\n",
> > +                                    state->plane->base.id, state->plane->name,
> > +                                    blob_version);
> > +                     return -EINVAL;
> > +             }
> > +     }
> > +
> > +     drm_property_blob_put(state->solid_fill_blob);
> > +
> > +     if (blob)
> > +             state->solid_fill_blob = drm_property_blob_get(blob);
> > +     else
> > +             state->solid_fill_blob = NULL;
> > +
> > +     return 0;
> > +}
> > +
> >   static void set_out_fence_for_crtc(struct drm_atomic_state *state,
> >                                  struct drm_crtc *crtc, s32 __user *fence_ptr)
> >   {
> > @@ -546,6 +591,13 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
> >               state->src_h = val;
> >       } else if (property == plane->pixel_source_property) {
> >               state->pixel_source = val;
> > +     } else if (property == plane->solid_fill_property) {
> > +             struct drm_property_blob *solid_fill = drm_property_lookup_blob(dev, val);
> > +
> > +             ret = drm_atomic_set_solid_fill_prop(state, solid_fill);
> > +             drm_property_blob_put(solid_fill);
> > +
> > +             return ret;
>
> Bonus point: dropping version from SOLID_FILL would allow us to use
> drm_atomic_replace_property_blob_from_id() here.
>
> >       } else if (property == plane->alpha_property) {
> >               state->alpha = val;
> >       } else if (property == plane->blend_mode_property) {
> > @@ -620,6 +672,9 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
> >               *val = state->src_h;
> >       } else if (property == plane->pixel_source_property) {
> >               *val = state->pixel_source;
> > +     } else if (property == plane->solid_fill_property) {
> > +             *val = state->solid_fill_blob ?
> > +                     state->solid_fill_blob->base.id : 0;
> >       } else if (property == plane->alpha_property) {
> >               *val = state->alpha;
> >       } else if (property == plane->blend_mode_property) {
> > diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c
> > index c500310a3d09..c632dfcd8a9b 100644
> > --- a/drivers/gpu/drm/drm_blend.c
> > +++ b/drivers/gpu/drm/drm_blend.c
> > @@ -200,6 +200,10 @@
> >    *  "FB":
> >    *          Framebuffer source set by the "FB_ID" property.
> >    *
> > + * solid_fill:
> > + *   solid_fill is set up with drm_plane_create_solid_fill_property(). It
> > + *   contains pixel data that drivers can use to fill a plane.
> > + *
> >    * Note that all the property extensions described here apply either to the
> >    * plane or the CRTC (e.g. for the background color, which currently is not
> >    * exposed and assumed to be black).
> > @@ -700,3 +704,29 @@ int drm_plane_create_pixel_source_property(struct drm_plane *plane,
> >       return 0;
> >   }
> >   EXPORT_SYMBOL(drm_plane_create_pixel_source_property);
> > +
> > +/**
> > + * drm_plane_create_solid_fill_property - create a new solid_fill property
> > + * @plane: drm plane
> > + *
> > + * This creates a new property blob that holds pixel data for solid fill planes.
> > + * The property is exposed to userspace as a property blob called "solid_fill".
> > + *
> > + * For information on what the blob contains, see `drm_mode_solid_fill`.
> > + */
> > +int drm_plane_create_solid_fill_property(struct drm_plane *plane)
> > +{
> > +     struct drm_property *prop;
> > +
> > +     prop = drm_property_create(plane->dev,
> > +                     DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_BLOB,
> > +                     "solid_fill", 0);
> > +     if (!prop)
> > +             return -ENOMEM;
> > +
> > +     drm_object_attach_property(&plane->base, prop, 0);
> > +     plane->solid_fill_property = prop;
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL(drm_plane_create_solid_fill_property);
> > diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h
> > index 122bbfbaae33..e7158fbee389 100644
> > --- a/include/drm/drm_blend.h
> > +++ b/include/drm/drm_blend.h
> > @@ -60,4 +60,5 @@ int drm_plane_create_blend_mode_property(struct drm_plane *plane,
> >                                        unsigned int supported_modes);
> >   int drm_plane_create_pixel_source_property(struct drm_plane *plane,
> >                                          unsigned long extra_sources);
> > +int drm_plane_create_solid_fill_property(struct drm_plane *plane);
> >   #endif
> > diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
> > index 89508b4dea4a..abf1458fa099 100644
> > --- a/include/drm/drm_plane.h
> > +++ b/include/drm/drm_plane.h
> > @@ -46,6 +46,17 @@ enum drm_plane_pixel_source {
> >       DRM_PLANE_PIXEL_SOURCE_MAX
> >   };
> >
> > +/**
> > + * struct solid_fill_property - RGB values for solid fill plane
> > + *
> > + * Note: This is the V1 for this feature
> > + */
> > +struct drm_solid_fill {
> > +     uint32_t r;
> > +     uint32_t g;
> > +     uint32_t b;
> > +};
> > +
> >   /**
> >    * struct drm_plane_state - mutable plane state
> >    *
> > @@ -130,6 +141,23 @@ struct drm_plane_state {
> >        */
> >       enum drm_plane_pixel_source pixel_source;
> >
> > +     /**
> > +      * @solid_fill_blob:
> > +      *
> > +      * Blob containing relevant information for a solid fill plane
> > +      * including pixel format and data. See
> > +      * drm_plane_create_solid_fill_property() for more details.
> > +      */
> > +     struct drm_property_blob *solid_fill_blob;
> > +
> > +     /**
> > +      * @solid_fill:
> > +      *
> > +      * Pixel data for solid fill planes. See
> > +      * drm_plane_create_solid_fill_property() for more details.
> > +      */
> > +     struct drm_solid_fill solid_fill;
> > +
> >       /**
> >        * @alpha:
> >        * Opacity of the plane with 0 as completely transparent and 0xffff as
> > @@ -720,6 +748,13 @@ struct drm_plane {
> >        */
> >       struct drm_property *pixel_source_property;
> >
> > +     /**
> > +      * @solid_fill_property:
> > +      * Optional solid_fill property for this plane. See
> > +      * drm_plane_create_solid_fill_property().
> > +      */
> > +     struct drm_property *solid_fill_property;
> > +
> >       /**
> >        * @alpha_property:
> >        * Optional alpha property for this plane. See
> > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> > index 43691058d28f..53c8efa5ad7f 100644
> > --- a/include/uapi/drm/drm_mode.h
> > +++ b/include/uapi/drm/drm_mode.h
> > @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
> >       char name[DRM_DISPLAY_MODE_LEN];
> >   };
> >
> > +/**
> > + * struct drm_mode_solid_fill - User info for solid fill planes
> > + *
> > + * This is the userspace API solid fill information structure.
> > + *
> > + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> > + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> > + * color and setting the pixel source to "SOLID_FILL".
> > + *
> > + * For information on the plane property, see drm_plane_create_solid_fill_property()
> > + *
> > + * @version: Version of the blob. Currently, there is only support for version == 1
> > + * @r: Red color value of single pixel
> > + * @g: Green color value of single pixel
> > + * @b: Blue color value of single pixel
> > + */
> > +struct drm_mode_solid_fill {
> > +     __u32 version;
> > +     __u32 r;
> > +     __u32 g;
> > +     __u32 b;
> > +};
> > +
> > +
> >   struct drm_mode_card_res {
> >       __u64 fb_id_ptr;
> >       __u64 crtc_id_ptr;
> >
>
> --
> With best wishes
> Dmitry
>
  

On Fri, Aug 4, 2023 at 3:27 PM Dmitry Baryshkov
<dmitry.baryshkov@linaro.org> wrote:
>
> On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
> >
> > Document and add support for solid_fill property to drm_plane. In
> > addition, add support for setting and getting the values for solid_fill.
> >
> > To enable solid fill planes, userspace must assign a property blob to
> > the "solid_fill" plane property containing the following information:
> >
> > struct drm_mode_solid_fill {
> >         u32 version;
> >         u32 r, g, b;
> > };
> >
> > Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> > ---
> >  drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
> >  drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
> >  drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
> >  include/drm/drm_blend.h                   |  1 +
> >  include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
> >  include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
> >  6 files changed, 154 insertions(+)
> >
>
> [skipped most of the patch]
>
> > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> > index 43691058d28f..53c8efa5ad7f 100644
> > --- a/include/uapi/drm/drm_mode.h
> > +++ b/include/uapi/drm/drm_mode.h
> > @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
> >         char name[DRM_DISPLAY_MODE_LEN];
> >  };
> >
> > +/**
> > + * struct drm_mode_solid_fill - User info for solid fill planes
> > + *
> > + * This is the userspace API solid fill information structure.
> > + *
> > + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> > + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> > + * color and setting the pixel source to "SOLID_FILL".
> > + *
> > + * For information on the plane property, see drm_plane_create_solid_fill_property()
> > + *
> > + * @version: Version of the blob. Currently, there is only support for version == 1
> > + * @r: Red color value of single pixel
> > + * @g: Green color value of single pixel
> > + * @b: Blue color value of single pixel
> > + */
> > +struct drm_mode_solid_fill {
> > +       __u32 version;
> > +       __u32 r;
> > +       __u32 g;
> > +       __u32 b;
>
> Another thought about the drm_mode_solid_fill uABI. I still think we
> should add alpha here. The reason is the following:
>
> It is true that we have  drm_plane_state::alpha and the plane's
> "alpha" property. However it is documented as "the plane-wide opacity
> [...] It can be combined with pixel alpha. The pixel values in the
> framebuffers are expected to not be pre-multiplied by the global alpha
> associated to the plane.".
>
> I can imagine a use case, when a user might want to enable plane-wide
> opacity, set "pixel blend mode" to "Coverage" and then switch between
> partially opaque framebuffer and partially opaque solid-fill without
> touching the plane's alpha value.

The only reason I see against this is that there might be some
hardware which supports only RGB but not alpha on planes and they
could then not use this property. Maybe another COLOR_FILL enum value
with alpha might be better? Maybe just doing the alpha via the alpha
property is good enough.

>
> --
> With best wishes
> Dmitry
>
  

On Fri, 4 Aug 2023 at 16:44, Sebastian Wick <sebastian.wick@redhat.com> wrote:
>
> On Fri, Aug 4, 2023 at 3:27 PM Dmitry Baryshkov
> <dmitry.baryshkov@linaro.org> wrote:
> >
> > On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
> > >
> > > Document and add support for solid_fill property to drm_plane. In
> > > addition, add support for setting and getting the values for solid_fill.
> > >
> > > To enable solid fill planes, userspace must assign a property blob to
> > > the "solid_fill" plane property containing the following information:
> > >
> > > struct drm_mode_solid_fill {
> > >         u32 version;
> > >         u32 r, g, b;
> > > };
> > >
> > > Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> > > ---
> > >  drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
> > >  drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
> > >  drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
> > >  include/drm/drm_blend.h                   |  1 +
> > >  include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
> > >  include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
> > >  6 files changed, 154 insertions(+)
> > >
> >
> > [skipped most of the patch]
> >
> > > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> > > index 43691058d28f..53c8efa5ad7f 100644
> > > --- a/include/uapi/drm/drm_mode.h
> > > +++ b/include/uapi/drm/drm_mode.h
> > > @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
> > >         char name[DRM_DISPLAY_MODE_LEN];
> > >  };
> > >
> > > +/**
> > > + * struct drm_mode_solid_fill - User info for solid fill planes
> > > + *
> > > + * This is the userspace API solid fill information structure.
> > > + *
> > > + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> > > + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> > > + * color and setting the pixel source to "SOLID_FILL".
> > > + *
> > > + * For information on the plane property, see drm_plane_create_solid_fill_property()
> > > + *
> > > + * @version: Version of the blob. Currently, there is only support for version == 1
> > > + * @r: Red color value of single pixel
> > > + * @g: Green color value of single pixel
> > > + * @b: Blue color value of single pixel
> > > + */
> > > +struct drm_mode_solid_fill {
> > > +       __u32 version;
> > > +       __u32 r;
> > > +       __u32 g;
> > > +       __u32 b;
> >
> > Another thought about the drm_mode_solid_fill uABI. I still think we
> > should add alpha here. The reason is the following:
> >
> > It is true that we have  drm_plane_state::alpha and the plane's
> > "alpha" property. However it is documented as "the plane-wide opacity
> > [...] It can be combined with pixel alpha. The pixel values in the
> > framebuffers are expected to not be pre-multiplied by the global alpha
> > associated to the plane.".
> >
> > I can imagine a use case, when a user might want to enable plane-wide
> > opacity, set "pixel blend mode" to "Coverage" and then switch between
> > partially opaque framebuffer and partially opaque solid-fill without
> > touching the plane's alpha value.
>
> The only reason I see against this is that there might be some
> hardware which supports only RGB but not alpha on planes and they
> could then not use this property.

Fair enough.

> Maybe another COLOR_FILL enum value
> with alpha might be better? Maybe just doing the alpha via the alpha
> property is good enough.

One of our customers has a use case for setting the opaque solid fill,
while keeping the plane's alpha intact.
  

On 8/4/2023 6:40 AM, Sebastian Wick wrote:
> On Mon, Jul 31, 2023 at 6:01 AM Dmitry Baryshkov
> <dmitry.baryshkov@linaro.org> wrote:
>>
>> On 28/07/2023 20:02, Jessica Zhang wrote:
>>> Document and add support for solid_fill property to drm_plane. In
>>> addition, add support for setting and getting the values for solid_fill.
>>>
>>> To enable solid fill planes, userspace must assign a property blob to
>>> the "solid_fill" plane property containing the following information:
>>>
>>> struct drm_mode_solid_fill {
>>>        u32 version;
>>>        u32 r, g, b;
>>> };
>>>
>>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>>> ---
>>>    drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>>>    drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>>>    drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>>>    include/drm/drm_blend.h                   |  1 +
>>>    include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>>>    include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>>>    6 files changed, 154 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
>>> index 01638c51ce0a..86fb876efbe6 100644
>>> --- a/drivers/gpu/drm/drm_atomic_state_helper.c
>>> +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
>>> @@ -254,6 +254,11 @@ void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
>>>        plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI;
>>>        plane_state->pixel_source = DRM_PLANE_PIXEL_SOURCE_FB;
>>>
>>> +     if (plane_state->solid_fill_blob) {
>>> +             drm_property_blob_put(plane_state->solid_fill_blob);
>>> +             plane_state->solid_fill_blob = NULL;
>>> +     }
>>> +
>>>        if (plane->color_encoding_property) {
>>>                if (!drm_object_property_get_default_value(&plane->base,
>>>                                                           plane->color_encoding_property,
>>> @@ -336,6 +341,9 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
>>>        if (state->fb)
>>>                drm_framebuffer_get(state->fb);
>>>
>>> +     if (state->solid_fill_blob)
>>> +             drm_property_blob_get(state->solid_fill_blob);
>>> +
>>>        state->fence = NULL;
>>>        state->commit = NULL;
>>>        state->fb_damage_clips = NULL;
>>> @@ -385,6 +393,7 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
>>>                drm_crtc_commit_put(state->commit);
>>>
>>>        drm_property_blob_put(state->fb_damage_clips);
>>> +     drm_property_blob_put(state->solid_fill_blob);
>>>    }
>>>    EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
>>>
>>> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
>>> index 454f980e16c9..039686c78c2a 100644
>>> --- a/drivers/gpu/drm/drm_atomic_uapi.c
>>> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
>>> @@ -316,6 +316,51 @@ drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
>>>    }
>>>    EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
>>>
>>> +static int drm_atomic_set_solid_fill_prop(struct drm_plane_state *state,
>>> +             struct drm_property_blob *blob)
>>> +{
>>> +     int blob_version;
>>> +
>>> +     if (blob == state->solid_fill_blob)
>>> +             return 0;
>>> +
>>> +     if (blob) {
>>> +             struct drm_mode_solid_fill *user_info = (struct drm_mode_solid_fill *)blob->data;
>>> +
>>> +             if (blob->length != sizeof(struct drm_mode_solid_fill)) {
>>> +                     drm_dbg_atomic(state->plane->dev,
>>> +                                    "[PLANE:%d:%s] bad solid fill blob length: %zu\n",
>>> +                                    state->plane->base.id, state->plane->name,
>>> +                                    blob->length);
>>> +                     return -EINVAL;
>>> +             }
>>> +
>>> +             blob_version = user_info->version;
>>
>> I remember that we had versioning for quite some time. However it stroke
>> me while reviewing that we do not a way to negotiate supported
>> SOLID_FILL versions. However as we now have support for different
>> pixel_source properties, maybe we can drop version completely. If at
>> some point a driver needs to support different kind of SOLID_FILL
>> property (consider v2), we can add new pixel source to the enum.
> 
> Agreed. Let's drop the versioning.

Acked.

Thanks,

Jessica Zhang

> 
>>
>>> +
>>> +             /* Add more versions if necessary */
>>> +             if (blob_version == 1) {
>>> +                     state->solid_fill.r = user_info->r;
>>> +                     state->solid_fill.g = user_info->g;
>>> +                     state->solid_fill.b = user_info->b;
>>> +             } else {
>>> +                     drm_dbg_atomic(state->plane->dev,
>>> +                                    "[PLANE:%d:%s] unsupported solid fill version (version=%d)\n",
>>> +                                    state->plane->base.id, state->plane->name,
>>> +                                    blob_version);
>>> +                     return -EINVAL;
>>> +             }
>>> +     }
>>> +
>>> +     drm_property_blob_put(state->solid_fill_blob);
>>> +
>>> +     if (blob)
>>> +             state->solid_fill_blob = drm_property_blob_get(blob);
>>> +     else
>>> +             state->solid_fill_blob = NULL;
>>> +
>>> +     return 0;
>>> +}
>>> +
>>>    static void set_out_fence_for_crtc(struct drm_atomic_state *state,
>>>                                   struct drm_crtc *crtc, s32 __user *fence_ptr)
>>>    {
>>> @@ -546,6 +591,13 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
>>>                state->src_h = val;
>>>        } else if (property == plane->pixel_source_property) {
>>>                state->pixel_source = val;
>>> +     } else if (property == plane->solid_fill_property) {
>>> +             struct drm_property_blob *solid_fill = drm_property_lookup_blob(dev, val);
>>> +
>>> +             ret = drm_atomic_set_solid_fill_prop(state, solid_fill);
>>> +             drm_property_blob_put(solid_fill);
>>> +
>>> +             return ret;
>>
>> Bonus point: dropping version from SOLID_FILL would allow us to use
>> drm_atomic_replace_property_blob_from_id() here.
>>
>>>        } else if (property == plane->alpha_property) {
>>>                state->alpha = val;
>>>        } else if (property == plane->blend_mode_property) {
>>> @@ -620,6 +672,9 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
>>>                *val = state->src_h;
>>>        } else if (property == plane->pixel_source_property) {
>>>                *val = state->pixel_source;
>>> +     } else if (property == plane->solid_fill_property) {
>>> +             *val = state->solid_fill_blob ?
>>> +                     state->solid_fill_blob->base.id : 0;
>>>        } else if (property == plane->alpha_property) {
>>>                *val = state->alpha;
>>>        } else if (property == plane->blend_mode_property) {
>>> diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c
>>> index c500310a3d09..c632dfcd8a9b 100644
>>> --- a/drivers/gpu/drm/drm_blend.c
>>> +++ b/drivers/gpu/drm/drm_blend.c
>>> @@ -200,6 +200,10 @@
>>>     *  "FB":
>>>     *          Framebuffer source set by the "FB_ID" property.
>>>     *
>>> + * solid_fill:
>>> + *   solid_fill is set up with drm_plane_create_solid_fill_property(). It
>>> + *   contains pixel data that drivers can use to fill a plane.
>>> + *
>>>     * Note that all the property extensions described here apply either to the
>>>     * plane or the CRTC (e.g. for the background color, which currently is not
>>>     * exposed and assumed to be black).
>>> @@ -700,3 +704,29 @@ int drm_plane_create_pixel_source_property(struct drm_plane *plane,
>>>        return 0;
>>>    }
>>>    EXPORT_SYMBOL(drm_plane_create_pixel_source_property);
>>> +
>>> +/**
>>> + * drm_plane_create_solid_fill_property - create a new solid_fill property
>>> + * @plane: drm plane
>>> + *
>>> + * This creates a new property blob that holds pixel data for solid fill planes.
>>> + * The property is exposed to userspace as a property blob called "solid_fill".
>>> + *
>>> + * For information on what the blob contains, see `drm_mode_solid_fill`.
>>> + */
>>> +int drm_plane_create_solid_fill_property(struct drm_plane *plane)
>>> +{
>>> +     struct drm_property *prop;
>>> +
>>> +     prop = drm_property_create(plane->dev,
>>> +                     DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_BLOB,
>>> +                     "solid_fill", 0);
>>> +     if (!prop)
>>> +             return -ENOMEM;
>>> +
>>> +     drm_object_attach_property(&plane->base, prop, 0);
>>> +     plane->solid_fill_property = prop;
>>> +
>>> +     return 0;
>>> +}
>>> +EXPORT_SYMBOL(drm_plane_create_solid_fill_property);
>>> diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h
>>> index 122bbfbaae33..e7158fbee389 100644
>>> --- a/include/drm/drm_blend.h
>>> +++ b/include/drm/drm_blend.h
>>> @@ -60,4 +60,5 @@ int drm_plane_create_blend_mode_property(struct drm_plane *plane,
>>>                                         unsigned int supported_modes);
>>>    int drm_plane_create_pixel_source_property(struct drm_plane *plane,
>>>                                           unsigned long extra_sources);
>>> +int drm_plane_create_solid_fill_property(struct drm_plane *plane);
>>>    #endif
>>> diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
>>> index 89508b4dea4a..abf1458fa099 100644
>>> --- a/include/drm/drm_plane.h
>>> +++ b/include/drm/drm_plane.h
>>> @@ -46,6 +46,17 @@ enum drm_plane_pixel_source {
>>>        DRM_PLANE_PIXEL_SOURCE_MAX
>>>    };
>>>
>>> +/**
>>> + * struct solid_fill_property - RGB values for solid fill plane
>>> + *
>>> + * Note: This is the V1 for this feature
>>> + */
>>> +struct drm_solid_fill {
>>> +     uint32_t r;
>>> +     uint32_t g;
>>> +     uint32_t b;
>>> +};
>>> +
>>>    /**
>>>     * struct drm_plane_state - mutable plane state
>>>     *
>>> @@ -130,6 +141,23 @@ struct drm_plane_state {
>>>         */
>>>        enum drm_plane_pixel_source pixel_source;
>>>
>>> +     /**
>>> +      * @solid_fill_blob:
>>> +      *
>>> +      * Blob containing relevant information for a solid fill plane
>>> +      * including pixel format and data. See
>>> +      * drm_plane_create_solid_fill_property() for more details.
>>> +      */
>>> +     struct drm_property_blob *solid_fill_blob;
>>> +
>>> +     /**
>>> +      * @solid_fill:
>>> +      *
>>> +      * Pixel data for solid fill planes. See
>>> +      * drm_plane_create_solid_fill_property() for more details.
>>> +      */
>>> +     struct drm_solid_fill solid_fill;
>>> +
>>>        /**
>>>         * @alpha:
>>>         * Opacity of the plane with 0 as completely transparent and 0xffff as
>>> @@ -720,6 +748,13 @@ struct drm_plane {
>>>         */
>>>        struct drm_property *pixel_source_property;
>>>
>>> +     /**
>>> +      * @solid_fill_property:
>>> +      * Optional solid_fill property for this plane. See
>>> +      * drm_plane_create_solid_fill_property().
>>> +      */
>>> +     struct drm_property *solid_fill_property;
>>> +
>>>        /**
>>>         * @alpha_property:
>>>         * Optional alpha property for this plane. See
>>> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
>>> index 43691058d28f..53c8efa5ad7f 100644
>>> --- a/include/uapi/drm/drm_mode.h
>>> +++ b/include/uapi/drm/drm_mode.h
>>> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>>>        char name[DRM_DISPLAY_MODE_LEN];
>>>    };
>>>
>>> +/**
>>> + * struct drm_mode_solid_fill - User info for solid fill planes
>>> + *
>>> + * This is the userspace API solid fill information structure.
>>> + *
>>> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
>>> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
>>> + * color and setting the pixel source to "SOLID_FILL".
>>> + *
>>> + * For information on the plane property, see drm_plane_create_solid_fill_property()
>>> + *
>>> + * @version: Version of the blob. Currently, there is only support for version == 1
>>> + * @r: Red color value of single pixel
>>> + * @g: Green color value of single pixel
>>> + * @b: Blue color value of single pixel
>>> + */
>>> +struct drm_mode_solid_fill {
>>> +     __u32 version;
>>> +     __u32 r;
>>> +     __u32 g;
>>> +     __u32 b;
>>> +};
>>> +
>>> +
>>>    struct drm_mode_card_res {
>>>        __u64 fb_id_ptr;
>>>        __u64 crtc_id_ptr;
>>>
>>
>> --
>> With best wishes
>> Dmitry
>>
>
  

On 8/4/2023 6:27 AM, Dmitry Baryshkov wrote:
> On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>>
>> Document and add support for solid_fill property to drm_plane. In
>> addition, add support for setting and getting the values for solid_fill.
>>
>> To enable solid fill planes, userspace must assign a property blob to
>> the "solid_fill" plane property containing the following information:
>>
>> struct drm_mode_solid_fill {
>>          u32 version;
>>          u32 r, g, b;
>> };
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>> ---
>>   drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>>   drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>>   drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>>   include/drm/drm_blend.h                   |  1 +
>>   include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>>   include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>>   6 files changed, 154 insertions(+)
>>
> 
> [skipped most of the patch]
> 
>> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
>> index 43691058d28f..53c8efa5ad7f 100644
>> --- a/include/uapi/drm/drm_mode.h
>> +++ b/include/uapi/drm/drm_mode.h
>> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>>          char name[DRM_DISPLAY_MODE_LEN];
>>   };
>>
>> +/**
>> + * struct drm_mode_solid_fill - User info for solid fill planes
>> + *
>> + * This is the userspace API solid fill information structure.
>> + *
>> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
>> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
>> + * color and setting the pixel source to "SOLID_FILL".
>> + *
>> + * For information on the plane property, see drm_plane_create_solid_fill_property()
>> + *
>> + * @version: Version of the blob. Currently, there is only support for version == 1
>> + * @r: Red color value of single pixel
>> + * @g: Green color value of single pixel
>> + * @b: Blue color value of single pixel
>> + */
>> +struct drm_mode_solid_fill {
>> +       __u32 version;
>> +       __u32 r;
>> +       __u32 g;
>> +       __u32 b;
> 
> Another thought about the drm_mode_solid_fill uABI. I still think we
> should add alpha here. The reason is the following:
> 
> It is true that we have  drm_plane_state::alpha and the plane's
> "alpha" property. However it is documented as "the plane-wide opacity
> [...] It can be combined with pixel alpha. The pixel values in the
> framebuffers are expected to not be pre-multiplied by the global alpha
> associated to the plane.".
> 
> I can imagine a use case, when a user might want to enable plane-wide
> opacity, set "pixel blend mode" to "Coverage" and then switch between
> partially opaque framebuffer and partially opaque solid-fill without
> touching the plane's alpha value.

Hi Dmitry,

I don't really agree that adding a solid fill alpha would be a good 
idea. Since the intent behind solid fill is to have a single color for 
the entire plane, I think it makes more sense to have solid fill rely on 
the global plane alpha.

As stated in earlier discussions, I think having both a solid_fill.alpha 
and a plane_state.alpha would be redundant and serve to confuse the user 
as to which one to set.

Thanks,

Jessica Zhang

> 
> -- 
> With best wishes
> Dmitry
  

On 8 August 2023 00:41:07 GMT+03:00, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>
>
>On 8/4/2023 6:27 AM, Dmitry Baryshkov wrote:
>> On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>>> 
>>> Document and add support for solid_fill property to drm_plane. In
>>> addition, add support for setting and getting the values for solid_fill.
>>> 
>>> To enable solid fill planes, userspace must assign a property blob to
>>> the "solid_fill" plane property containing the following information:
>>> 
>>> struct drm_mode_solid_fill {
>>>          u32 version;
>>>          u32 r, g, b;
>>> };
>>> 
>>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>>> ---
>>>   drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>>>   drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>>>   drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>>>   include/drm/drm_blend.h                   |  1 +
>>>   include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>>>   include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>>>   6 files changed, 154 insertions(+)
>>> 
>> 
>> [skipped most of the patch]
>> 
>>> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
>>> index 43691058d28f..53c8efa5ad7f 100644
>>> --- a/include/uapi/drm/drm_mode.h
>>> +++ b/include/uapi/drm/drm_mode.h
>>> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>>>          char name[DRM_DISPLAY_MODE_LEN];
>>>   };
>>> 
>>> +/**
>>> + * struct drm_mode_solid_fill - User info for solid fill planes
>>> + *
>>> + * This is the userspace API solid fill information structure.
>>> + *
>>> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
>>> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
>>> + * color and setting the pixel source to "SOLID_FILL".
>>> + *
>>> + * For information on the plane property, see drm_plane_create_solid_fill_property()
>>> + *
>>> + * @version: Version of the blob. Currently, there is only support for version == 1
>>> + * @r: Red color value of single pixel
>>> + * @g: Green color value of single pixel
>>> + * @b: Blue color value of single pixel
>>> + */
>>> +struct drm_mode_solid_fill {
>>> +       __u32 version;
>>> +       __u32 r;
>>> +       __u32 g;
>>> +       __u32 b;
>> 
>> Another thought about the drm_mode_solid_fill uABI. I still think we
>> should add alpha here. The reason is the following:
>> 
>> It is true that we have  drm_plane_state::alpha and the plane's
>> "alpha" property. However it is documented as "the plane-wide opacity
>> [...] It can be combined with pixel alpha. The pixel values in the
>> framebuffers are expected to not be pre-multiplied by the global alpha
>> associated to the plane.".
>> 
>> I can imagine a use case, when a user might want to enable plane-wide
>> opacity, set "pixel blend mode" to "Coverage" and then switch between
>> partially opaque framebuffer and partially opaque solid-fill without
>> touching the plane's alpha value.
>
>Hi Dmitry,
>
>I don't really agree that adding a solid fill alpha would be a good idea. Since the intent behind solid fill is to have a single color for the entire plane, I think it makes more sense to have solid fill rely on the global plane alpha.
>
>As stated in earlier discussions, I think having both a solid_fill.alpha and a plane_state.alpha would be redundant and serve to confuse the user as to which one to set.

That depends on the blending mode: in Coverage mode one has independent plane and contents alpha values. And I consider alpha value to be a part of the colour in the rgba/bgra modes.


>
>Thanks,
>
>Jessica Zhang
>
>> 
>> -- 
>> With best wishes
>> Dmitry
  

On 8/7/2023 6:07 PM, Dmitry Baryshkov wrote:
> 
> 
> On 8 August 2023 00:41:07 GMT+03:00, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>>
>>
>> On 8/4/2023 6:27 AM, Dmitry Baryshkov wrote:
>>> On Fri, 28 Jul 2023 at 20:03, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>>>>
>>>> Document and add support for solid_fill property to drm_plane. In
>>>> addition, add support for setting and getting the values for solid_fill.
>>>>
>>>> To enable solid fill planes, userspace must assign a property blob to
>>>> the "solid_fill" plane property containing the following information:
>>>>
>>>> struct drm_mode_solid_fill {
>>>>           u32 version;
>>>>           u32 r, g, b;
>>>> };
>>>>
>>>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>>>> ---
>>>>    drivers/gpu/drm/drm_atomic_state_helper.c |  9 +++++
>>>>    drivers/gpu/drm/drm_atomic_uapi.c         | 55 +++++++++++++++++++++++++++++++
>>>>    drivers/gpu/drm/drm_blend.c               | 30 +++++++++++++++++
>>>>    include/drm/drm_blend.h                   |  1 +
>>>>    include/drm/drm_plane.h                   | 35 ++++++++++++++++++++
>>>>    include/uapi/drm/drm_mode.h               | 24 ++++++++++++++
>>>>    6 files changed, 154 insertions(+)
>>>>
>>>
>>> [skipped most of the patch]
>>>
>>>> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
>>>> index 43691058d28f..53c8efa5ad7f 100644
>>>> --- a/include/uapi/drm/drm_mode.h
>>>> +++ b/include/uapi/drm/drm_mode.h
>>>> @@ -259,6 +259,30 @@ struct drm_mode_modeinfo {
>>>>           char name[DRM_DISPLAY_MODE_LEN];
>>>>    };
>>>>
>>>> +/**
>>>> + * struct drm_mode_solid_fill - User info for solid fill planes
>>>> + *
>>>> + * This is the userspace API solid fill information structure.
>>>> + *
>>>> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
>>>> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
>>>> + * color and setting the pixel source to "SOLID_FILL".
>>>> + *
>>>> + * For information on the plane property, see drm_plane_create_solid_fill_property()
>>>> + *
>>>> + * @version: Version of the blob. Currently, there is only support for version == 1
>>>> + * @r: Red color value of single pixel
>>>> + * @g: Green color value of single pixel
>>>> + * @b: Blue color value of single pixel
>>>> + */
>>>> +struct drm_mode_solid_fill {
>>>> +       __u32 version;
>>>> +       __u32 r;
>>>> +       __u32 g;
>>>> +       __u32 b;
>>>
>>> Another thought about the drm_mode_solid_fill uABI. I still think we
>>> should add alpha here. The reason is the following:
>>>
>>> It is true that we have  drm_plane_state::alpha and the plane's
>>> "alpha" property. However it is documented as "the plane-wide opacity
>>> [...] It can be combined with pixel alpha. The pixel values in the
>>> framebuffers are expected to not be pre-multiplied by the global alpha
>>> associated to the plane.".
>>>
>>> I can imagine a use case, when a user might want to enable plane-wide
>>> opacity, set "pixel blend mode" to "Coverage" and then switch between
>>> partially opaque framebuffer and partially opaque solid-fill without
>>> touching the plane's alpha value.
>>
>> Hi Dmitry,
>>
>> I don't really agree that adding a solid fill alpha would be a good idea. Since the intent behind solid fill is to have a single color for the entire plane, I think it makes more sense to have solid fill rely on the global plane alpha.
>>
>> As stated in earlier discussions, I think having both a solid_fill.alpha and a plane_state.alpha would be redundant and serve to confuse the user as to which one to set.
> 
> That depends on the blending mode: in Coverage mode one has independent plane and contents alpha values. And I consider alpha value to be a part of the colour in the rgba/bgra modes.

Acked -- taking Sebastian's concern into consideration, I think I'll 
have "PIXEL_SOURCE_SOLID_FILL_RGB" and add a separate 
"PIXEL_SOURCE_SOLID_FILL_RGBA".

Thanks,

Jessica Zhang

> 
> 
>>
>> Thanks,
>>
>> Jessica Zhang
>>
>>>
>>> -- 
>>> With best wishes
>>> Dmitry
> 
> -- 
> With best wishes
> Dmitry