| Message ID | 20240409-yuv-v6-8-de1c5728fd70@bootlin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/vkms: Reimplement line-per-line pixel conversion for plane reading | expand |
On Tue, 09 Apr 2024 15:25:26 +0200 Louis Chauvet <louis.chauvet@bootlin.com> wrote: > The pre_mul_alpha_blend is dedicated to blending, so to avoid mixing > different concepts (coordinate calculation and color management), extract > the x_limit and x_dst computation outside of this helper. > It also increases the maintainability by grouping the computation related > to coordinates in the same place: the loop in `blend`. > > Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> > --- > drivers/gpu/drm/vkms/vkms_composer.c | 40 +++++++++++++++++------------------- > 1 file changed, 19 insertions(+), 21 deletions(-) > > diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c > index da0651a94c9b..45b111c74884 100644 > --- a/drivers/gpu/drm/vkms/vkms_composer.c > +++ b/drivers/gpu/drm/vkms/vkms_composer.c > @@ -24,34 +24,30 @@ static u16 pre_mul_blend_channel(u16 src, u16 dst, u16 alpha) > > /** > * pre_mul_alpha_blend - alpha blending equation > - * @frame_info: Source framebuffer's metadata > * @stage_buffer: The line with the pixels from src_plane > * @output_buffer: A line buffer that receives all the blends output > + * @x_start: The start offset > + * @pixel_count: The number of pixels to blend > * > - * Using the information from the `frame_info`, this blends only the > - * necessary pixels from the `stage_buffer` to the `output_buffer` > - * using premultiplied blend formula. > + * The pixels 0..@pixel_count in stage_buffer are blended at @x_start..@x_start+@pixel_count in > + * output_buffer. > * > * The current DRM assumption is that pixel color values have been already > * pre-multiplied with the alpha channel values. See more > * drm_plane_create_blend_mode_property(). Also, this formula assumes a > * completely opaque background. > */ > -static void pre_mul_alpha_blend(struct vkms_frame_info *frame_info, > - struct line_buffer *stage_buffer, > - struct line_buffer *output_buffer) > +static void pre_mul_alpha_blend(const struct line_buffer *stage_buffer, > + struct line_buffer *output_buffer, int x_start, int pixel_count) > { > - int x_dst = frame_info->dst.x1; > - struct pixel_argb_u16 *out = output_buffer->pixels + x_dst; > - struct pixel_argb_u16 *in = stage_buffer->pixels; > - int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), > - stage_buffer->n_pixels); > - > - for (int x = 0; x < x_limit; x++) { > - out[x].a = (u16)0xffff; > - out[x].r = pre_mul_blend_channel(in[x].r, out[x].r, in[x].a); > - out[x].g = pre_mul_blend_channel(in[x].g, out[x].g, in[x].a); > - out[x].b = pre_mul_blend_channel(in[x].b, out[x].b, in[x].a); > + struct pixel_argb_u16 *out = &output_buffer->pixels[x_start]; > + const struct pixel_argb_u16 *in = stage_buffer->pixels; > + > + for (int i = 0; i < pixel_count; i++) { > + out[i].a = (u16)0xffff; > + out[i].r = pre_mul_blend_channel(in[i].r, out[i].r, in[i].a); > + out[i].g = pre_mul_blend_channel(in[i].g, out[i].g, in[i].a); > + out[i].b = pre_mul_blend_channel(in[i].b, out[i].b, in[i].a); > } > } > > @@ -183,7 +179,7 @@ static void blend(struct vkms_writeback_job *wb, > { > struct vkms_plane_state **plane = crtc_state->active_planes; > u32 n_active_planes = crtc_state->num_active_planes; > - int y_pos; > + int y_pos, x_dst, pixel_count; > > const struct pixel_argb_u16 background_color = { .a = 0xffff }; > > @@ -201,14 +197,16 @@ static void blend(struct vkms_writeback_job *wb, > > /* The active planes are composed associatively in z-order. */ > for (size_t i = 0; i < n_active_planes; i++) { > + x_dst = plane[i]->frame_info->dst.x1; > + pixel_count = min_t(int, drm_rect_width(&plane[i]->frame_info->dst), > + (int)stage_buffer->n_pixels); > y_pos = get_y_pos(plane[i]->frame_info, y); > > if (!check_limit(plane[i]->frame_info, y_pos)) > continue; > > vkms_compose_row(stage_buffer, plane[i], y_pos); > - pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer, > - output_buffer); > + pre_mul_alpha_blend(stage_buffer, output_buffer, x_dst, pixel_count); > } > > apply_lut(crtc_state, output_buffer); > Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.com> Thanks, pq
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c index da0651a94c9b..45b111c74884 100644 --- a/drivers/gpu/drm/vkms/vkms_composer.c +++ b/drivers/gpu/drm/vkms/vkms_composer.c @@ -24,34 +24,30 @@ static u16 pre_mul_blend_channel(u16 src, u16 dst, u16 alpha) /** * pre_mul_alpha_blend - alpha blending equation - * @frame_info: Source framebuffer's metadata * @stage_buffer: The line with the pixels from src_plane * @output_buffer: A line buffer that receives all the blends output + * @x_start: The start offset + * @pixel_count: The number of pixels to blend * - * Using the information from the `frame_info`, this blends only the - * necessary pixels from the `stage_buffer` to the `output_buffer` - * using premultiplied blend formula. + * The pixels 0..@pixel_count in stage_buffer are blended at @x_start..@x_start+@pixel_count in + * output_buffer. * * The current DRM assumption is that pixel color values have been already * pre-multiplied with the alpha channel values. See more * drm_plane_create_blend_mode_property(). Also, this formula assumes a * completely opaque background. */ -static void pre_mul_alpha_blend(struct vkms_frame_info *frame_info, - struct line_buffer *stage_buffer, - struct line_buffer *output_buffer) +static void pre_mul_alpha_blend(const struct line_buffer *stage_buffer, + struct line_buffer *output_buffer, int x_start, int pixel_count) { - int x_dst = frame_info->dst.x1; - struct pixel_argb_u16 *out = output_buffer->pixels + x_dst; - struct pixel_argb_u16 *in = stage_buffer->pixels; - int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), - stage_buffer->n_pixels); - - for (int x = 0; x < x_limit; x++) { - out[x].a = (u16)0xffff; - out[x].r = pre_mul_blend_channel(in[x].r, out[x].r, in[x].a); - out[x].g = pre_mul_blend_channel(in[x].g, out[x].g, in[x].a); - out[x].b = pre_mul_blend_channel(in[x].b, out[x].b, in[x].a); + struct pixel_argb_u16 *out = &output_buffer->pixels[x_start]; + const struct pixel_argb_u16 *in = stage_buffer->pixels; + + for (int i = 0; i < pixel_count; i++) { + out[i].a = (u16)0xffff; + out[i].r = pre_mul_blend_channel(in[i].r, out[i].r, in[i].a); + out[i].g = pre_mul_blend_channel(in[i].g, out[i].g, in[i].a); + out[i].b = pre_mul_blend_channel(in[i].b, out[i].b, in[i].a); } } @@ -183,7 +179,7 @@ static void blend(struct vkms_writeback_job *wb, { struct vkms_plane_state **plane = crtc_state->active_planes; u32 n_active_planes = crtc_state->num_active_planes; - int y_pos; + int y_pos, x_dst, pixel_count; const struct pixel_argb_u16 background_color = { .a = 0xffff }; @@ -201,14 +197,16 @@ static void blend(struct vkms_writeback_job *wb, /* The active planes are composed associatively in z-order. */ for (size_t i = 0; i < n_active_planes; i++) { + x_dst = plane[i]->frame_info->dst.x1; + pixel_count = min_t(int, drm_rect_width(&plane[i]->frame_info->dst), + (int)stage_buffer->n_pixels); y_pos = get_y_pos(plane[i]->frame_info, y); if (!check_limit(plane[i]->frame_info, y_pos)) continue; vkms_compose_row(stage_buffer, plane[i], y_pos); - pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer, - output_buffer); + pre_mul_alpha_blend(stage_buffer, output_buffer, x_dst, pixel_count); } apply_lut(crtc_state, output_buffer);
The pre_mul_alpha_blend is dedicated to blending, so to avoid mixing different concepts (coordinate calculation and color management), extract the x_limit and x_dst computation outside of this helper. It also increases the maintainability by grouping the computation related to coordinates in the same place: the loop in `blend`. Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> --- drivers/gpu/drm/vkms/vkms_composer.c | 40 +++++++++++++++++------------------- 1 file changed, 19 insertions(+), 21 deletions(-)