Message ID | 1535013020-23737-2-git-send-email-lowry.li@arm.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | drm/blend: Add per-plane pixel blend mode property | expand |
On Thu, Aug 23, 2018 at 04:30:19PM +0800, Lowry Li wrote: > 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. > Changes since v4: > - Adds comments in drm_blend.h. > - Removes setting default value in drm_plane_create_blend_mode_property() > as it is already in __drm_atomic_helper_plane_reset(). > - Fixes to use state->pixel_blend_mode instead of using > plane->state->pixel_blend_mode in reset function. > - Rebases on drm-misc-next. > > Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> I've also Reviewed the userspace component in drm_hwc here: https://gitlab.freedesktop.org/drm-hwcomposer/drm-hwcomposer/merge_requests/16#note_24690 Thanks, Sean > Signed-off-by: Lowry Li <lowry.li@arm.com> > --- > drivers/gpu/drm/drm_atomic.c | 4 ++ > drivers/gpu/drm/drm_atomic_helper.c | 1 + > drivers/gpu/drm/drm_blend.c | 123 ++++++++++++++++++++++++++++++++++++ > include/drm/drm_blend.h | 6 ++ > include/drm/drm_plane.h | 9 +++ > 5 files changed, 143 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..284a5d2 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]; > + 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..402b62d 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 +494,80 @@ 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); > + plane->blend_mode_property = prop; > + > + 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..35ef64a 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 +660,14 @@ struct drm_plane { > * drm_plane_create_rotation_property(). > */ > struct drm_property *rotation_property; > + /** > + * @blend_mode_property: > + * Optional "pixel blend mode" enum property for this plane. > + * Blend mode property represents the alpha blending equation selection, > + * describing how the pixels from the current plane are composited with > + * the background. > + */ > + struct drm_property *blend_mode_property; > > /** > * @color_encoding_property: > -- > 1.9.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
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..284a5d2 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]; + 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..402b62d 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 +494,80 @@ 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); + plane->blend_mode_property = prop; + + 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..35ef64a 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 +660,14 @@ struct drm_plane { * drm_plane_create_rotation_property(). */ struct drm_property *rotation_property; + /** + * @blend_mode_property: + * Optional "pixel blend mode" enum property for this plane. + * Blend mode property represents the alpha blending equation selection, + * describing how the pixels from the current plane are composited with + * the background. + */ + struct drm_property *blend_mode_property; /** * @color_encoding_property: