drm/vc4: Add support for plane alpha

The HVS supports mixing fixed alpha with per-pixel alpha or
setting a fixed plane alpha in case there is no per-pixel information.
This allows us to support the generic DRM plane alpha property.

Signed-off-by: Stefan Schake <stschake@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20180421000954.18936-1-stschake@gmail.com
This commit is contained in:
Stefan Schake 2018-04-20 17:09:54 -07:00 committed by Eric Anholt
parent 9f900de31d
commit 22445f0316
2 changed files with 18 additions and 4 deletions

View File

@ -201,6 +201,7 @@ static void vc4_plane_reset(struct drm_plane *plane)
return;
plane->state = &vc4_state->base;
plane->state->alpha = DRM_BLEND_ALPHA_OPAQUE;
vc4_state->base.plane = plane;
}
@ -467,6 +468,7 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
u32 ctl0_offset = vc4_state->dlist_count;
const struct hvs_format *format = vc4_get_hvs_format(fb->format->format);
int num_planes = drm_format_num_planes(format->drm);
bool mix_plane_alpha;
bool covers_screen;
u32 scl0, scl1, pitch0;
u32 lbm_size, tiling;
@ -552,7 +554,7 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
/* Position Word 0: Image Positions and Alpha Value */
vc4_state->pos0_offset = vc4_state->dlist_count;
vc4_dlist_write(vc4_state,
VC4_SET_FIELD(0xff, SCALER_POS0_FIXED_ALPHA) |
VC4_SET_FIELD(state->alpha >> 8, SCALER_POS0_FIXED_ALPHA) |
VC4_SET_FIELD(vc4_state->crtc_x, SCALER_POS0_START_X) |
VC4_SET_FIELD(vc4_state->crtc_y, SCALER_POS0_START_Y));
@ -565,6 +567,13 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
SCALER_POS1_SCL_HEIGHT));
}
/* Don't waste cycles mixing with plane alpha if the set alpha
* is opaque or there is no per-pixel alpha information.
* In any case we use the alpha property value as the fixed alpha.
*/
mix_plane_alpha = state->alpha != DRM_BLEND_ALPHA_OPAQUE &&
fb->format->has_alpha;
/* Position Word 2: Source Image Size, Alpha */
vc4_state->pos2_offset = vc4_state->dlist_count;
vc4_dlist_write(vc4_state,
@ -572,6 +581,7 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
SCALER_POS2_ALPHA_MODE_PIPELINE :
SCALER_POS2_ALPHA_MODE_FIXED,
SCALER_POS2_ALPHA_MODE) |
(mix_plane_alpha ? SCALER_POS2_ALPHA_MIX : 0) |
(fb->format->has_alpha ? SCALER_POS2_ALPHA_PREMULT : 0) |
VC4_SET_FIELD(vc4_state->src_w[0], SCALER_POS2_WIDTH) |
VC4_SET_FIELD(vc4_state->src_h[0], SCALER_POS2_HEIGHT));
@ -653,10 +663,11 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
vc4_state->crtc_w == state->crtc->mode.hdisplay &&
vc4_state->crtc_h == state->crtc->mode.vdisplay;
/* Background fill might be necessary when the plane has per-pixel
* alpha content and blends from the background or does not cover
* the entire screen.
* alpha content or a non-opaque plane alpha and could blend from the
* background or does not cover the entire screen.
*/
vc4_state->needs_bg_fill = fb->format->has_alpha || !covers_screen;
vc4_state->needs_bg_fill = fb->format->has_alpha || !covers_screen ||
state->alpha != DRM_BLEND_ALPHA_OPAQUE;
return 0;
}
@ -916,5 +927,7 @@ struct drm_plane *vc4_plane_init(struct drm_device *dev,
drm_plane_helper_add(plane, &vc4_plane_helper_funcs);
drm_plane_create_alpha_property(plane);
return plane;
}

View File

@ -945,6 +945,7 @@ enum hvs_pixel_format {
#define SCALER_POS2_ALPHA_MODE_FIXED_NONZERO 2
#define SCALER_POS2_ALPHA_MODE_FIXED_OVER_0x07 3
#define SCALER_POS2_ALPHA_PREMULT BIT(29)
#define SCALER_POS2_ALPHA_MIX BIT(28)
#define SCALER_POS2_HEIGHT_MASK VC4_MASK(27, 16)
#define SCALER_POS2_HEIGHT_SHIFT 16