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

From: Sebastian Wick
Date: Fri Aug 04 2023 - 09:42:09 EST


On Mon, Jul 31, 2023 at 6:01 AM Dmitry Baryshkov
<dmitry.baryshkov@xxxxxxxxxx> 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@xxxxxxxxxxx>
> > ---
> > 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
>