On Wed, Aug 22, 2018 at 03:27:44PM +0200, Maarten Lankhorst wrote: > Op 15-08-18 om 08:35 schreef Lowry Li: > > Pixel blend modes represent the alpha blending equation > > selection, describing how the pixels from the current > > plane are composited with the background. > > > > Adds a pixel_blend_mode to drm_plane_state and a > > blend_mode_property to drm_plane, and related support > > functions. > > > > Defines three blend modes in drm_blend.h. > > > > Changes since v1: > > - Moves the blending equation into the DOC comment > > - Refines the comments of drm_plane_create_blend_mode_property to not > > enumerate the #defines, but instead the string values > > - Uses fg.* instead of pixel.* and plane_alpha instead of plane.alpha > > Changes since v2: > > - Refines the comments of drm_plane_create_blend_mode_property: > > 1) Puts the descriptions (after the ":") on a new line > > 2) Adds explaining why @supported_modes need PREMUL as default > > Changes since v3: > > - Refines drm_plane_create_blend_mode_property(). drm_property_add_enum() > > can calculate the index itself just fine, so no point in having the > > caller pass it in. > > - Since the current DRM assumption is that alpha is premultiplied > > as default, define DRM_MODE_BLEND_PREMULTI as 0 will be better. > > - Refines some comments. > > > > Signed-off-by: Lowry Li <lowry.li@xxxxxxx> > > --- > > drivers/gpu/drm/drm_atomic.c | 4 ++ > > drivers/gpu/drm/drm_atomic_helper.c | 1 + > > drivers/gpu/drm/drm_blend.c | 126 ++++++++++++++++++++++++++++++++++++ > > include/drm/drm_blend.h | 6 ++ > > include/drm/drm_plane.h | 2 + > > 5 files changed, 139 insertions(+) > > > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > > index 3eb061e..d0478ab 100644 > > --- a/drivers/gpu/drm/drm_atomic.c > > +++ b/drivers/gpu/drm/drm_atomic.c > > @@ -895,6 +895,8 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane, > > state->src_h = val; > > } else if (property == plane->alpha_property) { > > state->alpha = val; > > + } else if (property == plane->blend_mode_property) { > > + state->pixel_blend_mode = val; > > } else if (property == plane->rotation_property) { > > if (!is_power_of_2(val & DRM_MODE_ROTATE_MASK)) { > > DRM_DEBUG_ATOMIC("[PLANE:%d:%s] bad rotation bitmask: 0x%llx\n", > > @@ -968,6 +970,8 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane, > > *val = state->src_h; > > } else if (property == plane->alpha_property) { > > *val = state->alpha; > > + } else if (property == plane->blend_mode_property) { > > + *val = state->pixel_blend_mode; > > } else if (property == plane->rotation_property) { > > *val = state->rotation; > > } else if (property == plane->zpos_property) { > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > > index 6dd5036..563af09 100644 > > --- a/drivers/gpu/drm/drm_atomic_helper.c > > +++ b/drivers/gpu/drm/drm_atomic_helper.c > > @@ -3569,6 +3569,7 @@ void __drm_atomic_helper_plane_reset(struct drm_plane *plane, > > /* Reset the alpha value to fully opaque if it matters */ > > if (plane->alpha_property) > > state->alpha = plane->alpha_property->values[1]; > > + plane->state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI; > > > > plane->state = state; > > } > > diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c > > index a16a74d..24016c9 100644 > > --- a/drivers/gpu/drm/drm_blend.c > > +++ b/drivers/gpu/drm/drm_blend.c > > @@ -107,6 +107,52 @@ > > * planes. Without this property the primary plane is always below the cursor > > * plane, and ordering between all other planes is undefined. > > * > > + * pixel blend mode: > > + * Pixel blend mode is set up with drm_plane_create_blend_mode_property(). > > + * It adds a blend mode for alpha blending equation selection, describing > > + * how the pixels from the current plane are composited with the > > + * background. > > + * > > + * Three alpha blending equations are defined: > > + * > > + * "None": > > + * Blend formula that ignores the pixel alpha:: > > + * > > + * out.rgb = plane_alpha * fg.rgb + > > + * (1 - plane_alpha) * bg.rgb > > + * > > + * "Pre-multiplied": > > + * Blend formula that assumes the pixel color values > > + * have been already pre-multiplied with the alpha > > + * channel values:: > > + * > > + * out.rgb = plane_alpha * fg.rgb + > > + * (1 - (plane_alpha * fg.alpha)) * bg.rgb > > + * > > + * "Coverage": > > + * Blend formula that assumes the pixel color values have not > > + * been pre-multiplied and will do so when blending them to the > > + * background color values:: > > + * > > + * out.rgb = plane_alpha * fg.alpha * fg.rgb + > > + * (1 - (plane_alpha * fg.alpha)) * bg.rgb > > + * > > + * Using the following symbols: > > + * > > + * "fg.rgb": > > + * Each of the RGB component values from the plane's pixel > > + * "fg.alpha": > > + * Alpha component value from the plane's pixel. If the plane's > > + * pixel format has no alpha component, then this is assumed to be > > + * 1.0. In these cases, this property has no effect, as all three > > + * equations become equivalent. > > + * "bg.rgb": > > + * Each of the RGB component values from the background > > + * "plane_alpha": > > + * Plane alpha value set by the plane "alpha" property. If the > > + * plane does not expose the "alpha" property, then this is > > + * assumed to be 1.0 > > + * > > * 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). > > @@ -448,3 +494,83 @@ int drm_atomic_normalize_zpos(struct drm_device *dev, > > return 0; > > } > > EXPORT_SYMBOL(drm_atomic_normalize_zpos); > > + > > +/** > > + * drm_plane_create_blend_mode_property - create a new blend mode property > > + * @plane: drm plane > > + * @supported_modes: bitmask of supported modes, must include > > + * BIT(DRM_MODE_BLEND_PREMULTI). Current DRM assumption is > > + * that alpha is premultiplied, and old userspace can break if > > + * the property defaults to anything else. > > + * > > + * This creates a new property describing the blend mode. > > + * > > + * The property exposed to userspace is an enumeration property (see > > + * drm_property_create_enum()) called "pixel blend mode" and has the > > + * following enumeration values: > > + * > > + * "None": > > + * Blend formula that ignores the pixel alpha. > > + * > > + * "Pre-multiplied": > > + * Blend formula that assumes the pixel color values have been already > > + * pre-multiplied with the alpha channel values. > > + * > > + * "Coverage": > > + * Blend formula that assumes the pixel color values have not been > > + * pre-multiplied and will do so when blending them to the background color > > + * values. > > + * > > + * RETURNS: > > + * Zero for success or -errno > > + */ > > +int drm_plane_create_blend_mode_property(struct drm_plane *plane, > > + unsigned int supported_modes) > > +{ > > + struct drm_device *dev = plane->dev; > > + struct drm_property *prop; > > + static const struct drm_prop_enum_list props[] = { > > + { DRM_MODE_BLEND_PIXEL_NONE, "None" }, > > + { DRM_MODE_BLEND_PREMULTI, "Pre-multiplied" }, > > + { DRM_MODE_BLEND_COVERAGE, "Coverage" }, > > + }; > > + unsigned int valid_mode_mask = BIT(DRM_MODE_BLEND_PIXEL_NONE) | > > + BIT(DRM_MODE_BLEND_PREMULTI) | > > + BIT(DRM_MODE_BLEND_COVERAGE); > > + int i; > > + > > + if (WARN_ON((supported_modes & ~valid_mode_mask) || > > + ((supported_modes & BIT(DRM_MODE_BLEND_PREMULTI)) == 0))) > > + return -EINVAL; > > + > > + prop = drm_property_create(dev, DRM_MODE_PROP_ENUM, > > + "pixel blend mode", > > + hweight32(supported_modes)); > > + if (!prop) > > + return -ENOMEM; > > + > > + for (i = 0; i < ARRAY_SIZE(props); i++) { > > + int ret; > > + > > + if (!(BIT(props[i].type) & supported_modes)) > > + continue; > > + > > + ret = drm_property_add_enum(prop, props[i].type, > > + props[i].name); > > + > > + if (ret) { > > + drm_property_destroy(dev, prop); > > + > > + return ret; > > + } > > + } > > + > > + drm_object_attach_property(&plane->base, prop, DRM_MODE_BLEND_PREMULTI); > Do we still care about !atomic kernel drivers? Hi Maarten, Thanks for your comments. We don't need to care about this. And DRM_MODE_BLEND_PREMULTI is zero as default. > > + plane->blend_mode_property = prop; > > + > > + if (plane->state) > > + plane->state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI; > > Is this still needed with the hunk in __drm_atomic_helper_plane_reset() ? I would just remove it. Totally agree. Will remove this. Thanks a lot:) > > + > > + return 0; > > +} > > +EXPORT_SYMBOL(drm_plane_create_blend_mode_property); > > diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h > > index 330c561..88bdfec 100644 > > --- a/include/drm/drm_blend.h > > +++ b/include/drm/drm_blend.h > > @@ -27,6 +27,10 @@ > > #include <linux/ctype.h> > > #include <drm/drm_mode.h> > > > > +#define DRM_MODE_BLEND_PREMULTI 0 > > +#define DRM_MODE_BLEND_COVERAGE 1 > > +#define DRM_MODE_BLEND_PIXEL_NONE 2 > > + > > struct drm_device; > > struct drm_atomic_state; > > struct drm_plane; > > @@ -52,4 +56,6 @@ int drm_plane_create_zpos_immutable_property(struct drm_plane *plane, > > unsigned int zpos); > > int drm_atomic_normalize_zpos(struct drm_device *dev, > > struct drm_atomic_state *state); > > +int drm_plane_create_blend_mode_property(struct drm_plane *plane, > > + unsigned int supported_modes); > > #endif > > diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h > > index 8a152dc..c52614a 100644 > > --- a/include/drm/drm_plane.h > > +++ b/include/drm/drm_plane.h > > @@ -117,6 +117,7 @@ struct drm_plane_state { > > * details. > > */ > > u16 alpha; > > + uint16_t pixel_blend_mode; > > > > /** > > * @rotation: > > @@ -659,6 +660,7 @@ struct drm_plane { > > * drm_plane_create_rotation_property(). > > */ > > struct drm_property *rotation_property; > > + struct drm_property *blend_mode_property; > > > > /** > > * @color_encoding_property: > > These need to be documented. Yes, will add this. Thanks. > With those changes: > > Reviewed-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> > > ~Maarten -- Regards, Lowry _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel