This patch adds code and documentation for the following blending related properties: 'alpha', 'blending' and 'alpha_premult'.
'alpha' property defines plane's transparency used for some blending modes.
'alpha_premult' property defines if RGB pixel data in the framebuffer contains values pre-multiplied by its alpha value or full range RGB values (0-255), which needs to be multiplied by pixel alpha value for blending operation.
'blending' property selects blending mode - by selecting one of the predefined values, user can select a pair of factors, which will be used in the generic blending equation. For more information, see the kerneldoc for the added code.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- Documentation/DocBook/gpu.tmpl | 47 +++++++++++++++++- drivers/gpu/drm/drm_atomic.c | 12 +++++ drivers/gpu/drm/drm_blend.c | 110 +++++++++++++++++++++++++++++++++++++++++ include/drm/drm_crtc.h | 15 ++++++ include/uapi/drm/drm_mode.h | 101 +++++++++++++++++++++++++++++++++++++ 5 files changed, 283 insertions(+), 2 deletions(-)
diff --git a/Documentation/DocBook/gpu.tmpl b/Documentation/DocBook/gpu.tmpl index ae7d913adf60..e5197368e68f 100644 --- a/Documentation/DocBook/gpu.tmpl +++ b/Documentation/DocBook/gpu.tmpl @@ -1110,6 +1110,22 @@ int max_width, max_height;</synopsis> </sect2> </sect1>
+ <!-- Internals: plane blending --> + + <sect1 id="drm-plane-blending"> + <title>Plane blending</title> + + <sect2> + <title>Plane Blending Overview</title> +!Pinclude/uapi/drm/drm_mode.h Generic plane blending operation + </sect2> + <sect2> + <title>Blending Function Reference</title> +!Iinclude/uapi/drm/drm_mode.h +!Edrivers/gpu/drm/drm_blend.c + </sect2> + </sect1> + <!-- Internals: kms initialization and cleanup -->
<sect1 id="drm-kms-init"> @@ -1816,7 +1832,7 @@ void intel_crt_init(struct drm_device *dev) <td valign="top" >Description/Restrictions</td> </tr> <tr> - <td rowspan="38" valign="top" >DRM</td> + <td rowspan="41" valign="top" >DRM</td> <td valign="top" >Generic</td> <td valign="top" >“rotation”</td> <td valign="top" >BITMASK</td> @@ -2068,7 +2084,7 @@ void intel_crt_init(struct drm_device *dev) <td valign="top" >property to suggest an Y offset for a connector</td> </tr> <tr> - <td rowspan="4" valign="top" >Optional</td> + <td rowspan="7" valign="top" >Optional</td> <td valign="top" >“scaling mode”</td> <td valign="top" >ENUM</td> <td valign="top" >{ "None", "Full", "Center", "Full aspect" }</td> @@ -2102,6 +2118,33 @@ void intel_crt_init(struct drm_device *dev) planes' order. Exact value range is driver dependent.</td> </tr> <tr> + <td valign="top" > "alpha" </td> + <td valign="top" >RANGE</td> + <td valign="top" >Min=0, Max= driver dependent</td> + <td valign="top" >Plane</td> + <td valign="top" >Plane's alpha value (transparency) for blending operation. Used in some blending modes. </td> + </tr> + <tr> + <td valign="top" > "alpha_premult" </td> + <td valign="top" >BOOL</td> + <td valign="top" >Min=0, Max=1</td> + <td valign="top" >Plane</td> + <td valign="top" >Indicates the range of the RGB data of the framebuffer attached to the given plane. + When enabled, RGB values fits the range from 0 to pixel's alpha value. When disabled, RGB + values are from 0 to 255 range and during blending operations they will be multiplied by + the pixel's alpha value first before computing result of blending equations. Value of this + property is used in some blending modes and only when user attaches framebuffer with pixel + format, which contains non-binary alpha channel.</td> + </tr> + <tr> + <td valign="top" > "blending" </td> + <td valign="top" >ENUM</td> + <td valign="top" >{ "disabled", "pixel-alpha", "const-alpha" "pixel-const-alpha" }</td> + <td valign="top" >Plane</td> + <td valign="top" >Selects algorithm used in plane blending operation. For more information, see + DRM_BLEND_* symbolic constant documentation. </td> + </tr> + <tr> <td rowspan="20" valign="top" >i915</td> <td rowspan="2" valign="top" >Generic</td> <td valign="top" >"Broadcast RGB"</td> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index a19201efb7d1..a85da144fd95 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -632,6 +632,12 @@ int drm_atomic_plane_set_property(struct drm_plane *plane, state->rotation = val; } else if (property == config->zpos_property) { state->zpos = val; + } else if (property == config->alpha_property) { + state->alpha = val; + } else if (property == config->alpha_premult_property) { + state->alpha_premult = val; + } else if (property == config->blending_property) { + state->blending = val; } else if (plane->funcs->atomic_set_property) { return plane->funcs->atomic_set_property(plane, state, property, val); @@ -690,6 +696,12 @@ drm_atomic_plane_get_property(struct drm_plane *plane, *val = state->rotation; } else if (property == config->zpos_property) { *val = state->zpos; + } else if (property == config->alpha_property) { + *val = state->alpha; + } else if (property == config->alpha_premult_property) { + *val = state->alpha_premult; + } else if (property == config->blending_property) { + *val = state->blending; } else if (plane->funcs->atomic_get_property) { return plane->funcs->atomic_get_property(plane, state, property, val); } else { diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c index cdcb647c8ed9..eb7996a848df 100644 --- a/drivers/gpu/drm/drm_blend.c +++ b/drivers/gpu/drm/drm_blend.c @@ -99,6 +99,116 @@ int drm_mode_create_zpos_immutable_property(struct drm_device *dev, } EXPORT_SYMBOL(drm_mode_create_zpos_immutable_property);
+/** + * drm_mode_create_blending_property - create generic blending property + * @dev: DRM device + * @supported_blendings: array of supported blending modes + * @supported_blendings_count: size of @supported_blendings array + * + * This function initializes generic blending property to selected subset + * of supported blending modes. Drivers can then attach this property to + * planes to let userspace to configure different blending modes. For more + * information on blending modes, see DRM_BLEND_* defines. + * + * Returns: + * Zero on success, negative errno on failure. + */ +int drm_mode_create_blending_property(struct drm_device *dev, + unsigned int *supported_blendings, + unsigned int supported_blendings_count) +{ + struct drm_property *prop; + static const struct drm_prop_enum_list all_values[] = { + { DRM_BLEND_DISABLED, "disabled" }, + { DRM_BLEND_PIXEL_ALPHA, "pixel-alpha" }, + { DRM_BLEND_CONST_ALPHA, "const-alpha" }, + { DRM_BLEND_PIXEL_CONST_ALPHA, "pixel-const-alpha" }, + }; + struct drm_prop_enum_list *values; + int i, j; + + values = kmalloc(supported_blendings_count * sizeof(*values), + GFP_KERNEL); + if (!values) + return -ENOMEM; + + for (i = 0; i < supported_blendings_count; i++) { + for (j = 0; j < ARRAY_SIZE(all_values); j++) { + if (all_values[j].type == supported_blendings[i]) { + values[i].type = supported_blendings[i]; + values[i].name = all_values[j].name; + break; + } + } + } + + prop = drm_property_create_enum(dev, 0, "blending", values, + supported_blendings_count); + kfree(values); + + if (!prop) + return -ENOMEM; + + dev->mode_config.blending_property = prop; + return 0; +} +EXPORT_SYMBOL(drm_mode_create_blending_property); + +/** + * drm_mode_create_alpha_property - create plane alpha property + * @dev: DRM device + * @max: maximal possible value of alpha property + * + * This function initializes generic plane's alpha property. It's value is used + * for blending operations, depending on selected blending mode. For more + * information, see DRM_BLEND_* modes and its documentation. Maximum alpha value + * is determined by the driver. + * + * Returns: + * Zero on success, negative errno on failure. + */ +int drm_mode_create_alpha_property(struct drm_device *dev, unsigned int max) +{ + struct drm_property *prop; + + prop = drm_property_create_range(dev, 0, "alpha", 0, max); + if (!prop) + return -ENOMEM; + + dev->mode_config.alpha_property = prop; + return 0; +} +EXPORT_SYMBOL(drm_mode_create_alpha_property); + +/** + * drm_mode_create_alpha_premult_property - create muttable zpos property + * @dev: DRM device + * + * This function initializes generic plane's alpha pre-multiplication property. + * This property indicates the range of the RGB data of the framebuffer attached + * to the given plane. When enabled, RGB values fits the range from 0 to pixel's + * alpha value. When disabled, RGB values are from 0 to 255 range and during + * blending operations they will be multiplied by the pixel's alpha value first + * before computing result of blending equations. Value of this property is used + * only when user attaches framebuffer with pixel format, which contains + * non-binary alpha channel (for example: DRM_FORMAT_ARGB8888). + * + * Returns: + * Zero on success, negative errno on failure. + */ +int drm_mode_create_alpha_premult_property(struct drm_device *dev) +{ + struct drm_property *prop; + + prop = drm_property_create_bool(dev, 0, "alpha_premult"); + if (!prop) + return -ENOMEM; + + dev->mode_config.alpha_premult_property = prop; + return 0; +} +EXPORT_SYMBOL(drm_mode_create_alpha_premult_property); + static int drm_atomic_state_zpos_cmp(const void *a, const void *b) { const struct drm_plane_state *sa = *(struct drm_plane_state **)a; diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 702f4f28f580..47ae79483a19 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -1276,6 +1276,11 @@ struct drm_plane_state { unsigned int zpos; unsigned int normalized_zpos;
+ /* Plane blending */ + unsigned int blending; + unsigned int alpha; + bool alpha_premult; + struct drm_atomic_state *state; };
@@ -2098,6 +2103,9 @@ struct drm_mode_config { struct drm_property *rotation_property; struct drm_property *zpos_property; struct drm_property *zpos_immutable_property; + struct drm_property *blending_property; + struct drm_property *alpha_property; + struct drm_property *alpha_premult_property; struct drm_property *prop_src_x; struct drm_property *prop_src_y; struct drm_property *prop_src_w; @@ -2505,6 +2513,13 @@ extern int drm_mode_create_zpos_immutable_property(struct drm_device *dev, unsigned int min, unsigned int max);
+extern int drm_mode_create_blending_property(struct drm_device *dev, + unsigned int *supported_blendings, + unsigned int supported_blendings_count); +extern int drm_mode_create_alpha_property(struct drm_device *dev, + unsigned int max); +extern int drm_mode_create_alpha_premult_property(struct drm_device *dev); + /* Helpers */
static inline struct drm_plane *drm_plane_find(struct drm_device *dev, diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index 50adb46204c2..6da7076a3856 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -596,4 +596,105 @@ struct drm_mode_destroy_blob { __u32 blob_id; };
+/** + * DOC: Generic plane blending operation + * + * Planes attached to one CRTC are blended by the hardware to produce the final + * result on the display. The order of planes during blending operation is + * determined by 'zpos' property. When order of plane for blending operation is + * determined, then framebuffers of all planes are placed on the display area + * according to the configured position and target size. + * + * Then one of the selected blending procedure is applied to each pixel on the + * display area to compute the final result of the blending. The blending + * procedure is similar to the well known glBlendFunc() API. + * + * The generic equation for blending is: + * outputRGB = sF * sRGB + dF * dRGB + * + * @sRGB: are RGB values of blended plane + * + * @dRGB: are RGB values of plane's background (result of previous blending or + * RGB pixel values of deeper planes). + * + * @sF and @dF: are one of DRM_FACTOR_* symbolic constants. + * + * Blending mode then defined as DRM_BLEND(sF, dF), which selects respective + * factors for the above equation. For more information, see drm_blend_mode + * enum. + */ + +/** + * enum drm_blend_factor - factors for defining plane blending formula + * @DRM_FACTOR_ZERO: constant zero + * @DRM_FACTOR_ONE: constant one + * @DRM_FACTOR_SRC_ALPHA: pixel alpha value + * @DRM_FACTOR_ONE_MINUS_SRC_ALPHA: 1 - DRM_FACTOR_SRC_ALPHA + * @DRM_FACTOR_CONST_ALPHA: constant alpha (plane's property) + * @DRM_FACTOR_ONE_MINUS_CONST_ALPHA: 1 - DRM_FACTOR_CONST_ALPHA + * @DRM_FACTOR_SRC_CONST_ALPHA: pixel alpha value multiplied by plane's + * constant alpha + * @DRM_FACTOR_ONE_MINUS_SRC_CONST_ALPHA: 1 - DRM_FACTOR_SRC_CONST_ALPHA + * + * Values of this enum are used to define plane blending formula. Two factors + * have to be selected - one for source plane and one for destination + * (background). + */ +enum drm_blend_factor { + DRM_FACTOR_ZERO, + DRM_FACTOR_ONE, + DRM_FACTOR_SRC_ALPHA, + DRM_FACTOR_ONE_MINUS_SRC_ALPHA, + DRM_FACTOR_CONST_ALPHA, + DRM_FACTOR_ONE_MINUS_CONST_ALPHA, + DRM_FACTOR_SRC_CONST_ALPHA, + DRM_FACTOR_ONE_MINUS_SRC_CONST_ALPHA, +}; + +#define DRM_BLEND(s, d) ((d << 16) | (s)) + +/** + * enum drm_blend_mode - predefined blending modes + * @DRM_BLEND_S_ONE_D_ZERO: no transparency; per-pixel and plane's alpha is + * ignored regardless of the selected pixel format. + * @DRM_BLEND_S_SRC_ALPHA_D_ONE_MINUS_SRC_ALPHA: blending with per-pixel alpha; + * plane's alpha is ignored, aplies only when pixel format defines alpha + * channel, otherwise same as @DRM_BLEND_DISABLED and + * @DRM_BLEND_S_ONE_D_ZERO. + * @DRM_BLEND_S_CONST_ALPHA_D_ONE_MINUS_CONST_ALPHA: blending with constant + * alpha; per-pixel alpha is ignored regardless of the selected pixel + * format. + * @DRM_BLEND_S_SRC_CONST_ALPHA_D_ONE_MINUS_SRC_CONST_ALPHA: blending with both + * per-pixel and plane's alpha; aplies only when pixel format defines alpha + * channel, otherwise same as @DRM_BLEND_CONST_ALPHA and + * @DRM_BLEND_S_CONST_ALPHA_D_ONE_MINUS_CONST_ALPHA + * @DRM_BLEND_DISABLED: same as @DRM_BLEND_S_ONE_D_ZERO + * @DRM_BLEND_PIXEL_ALPHA: same as @DRM_BLEND_S_SRC_ALPHA_D_ONE_MINUS_SRC_ALPHA, + * @DRM_BLEND_CONST_ALPHA: same as + * @DRM_BLEND_S_CONST_ALPHA_D_ONE_MINUS_CONST_ALPHA, + * @DRM_BLEND_PIXEL_CONST_ALPHA: same as + * @DRM_BLEND_S_SRC_CONST_ALPHA_D_ONE_MINUS_SRC_CONST_ALPHA, + * + * Values of this enum can be set to 'blend' plane's property. The actual + * value of each blending mode consists of two drm_blend_factor values + * encoded on lower 16 bits for source plane and higher 16 bits for destiantion + * (background). + */ +enum drm_blend_mode { + DRM_BLEND_S_ONE_D_ZERO = DRM_BLEND(DRM_FACTOR_ONE, DRM_FACTOR_ZERO), + DRM_BLEND_S_SRC_ALPHA_D_ONE_MINUS_SRC_ALPHA = + DRM_BLEND(DRM_FACTOR_SRC_ALPHA, + DRM_FACTOR_ONE_MINUS_SRC_ALPHA), + DRM_BLEND_S_CONST_ALPHA_D_ONE_MINUS_CONST_ALPHA = + DRM_BLEND(DRM_FACTOR_CONST_ALPHA, + DRM_FACTOR_ONE_MINUS_CONST_ALPHA), + DRM_BLEND_S_SRC_CONST_ALPHA_D_ONE_MINUS_SRC_CONST_ALPHA = + DRM_BLEND(DRM_FACTOR_SRC_CONST_ALPHA, + DRM_FACTOR_ONE_MINUS_SRC_CONST_ALPHA), + DRM_BLEND_DISABLED = DRM_BLEND_S_ONE_D_ZERO, + DRM_BLEND_PIXEL_ALPHA = DRM_BLEND_S_SRC_ALPHA_D_ONE_MINUS_SRC_ALPHA, + DRM_BLEND_CONST_ALPHA = DRM_BLEND_S_CONST_ALPHA_D_ONE_MINUS_CONST_ALPHA, + DRM_BLEND_PIXEL_CONST_ALPHA = DRM_BLEND_S_SRC_CONST_ALPHA_D_ONE_MINUS_SRC_CONST_ALPHA, +}; + #endif