On Mon, 4 Apr 2022 17:45:11 -0300 Igor Torrente wrote: > This commit is the groundwork to introduce new formats to the planes and > writeback buffer. As part of it, a new buffer metadata field is added to > `vkms_writeback_job`, this metadata is represented by the `vkms_composer` > struct. Hi, should this be talking about vkms_frame_info struct instead? > > Also adds two new function pointers (`{wb,plane}_format_transform_func`) > are defined to handle format conversion to/from internal format. > > These things will allow us, in the future, to have different compositing > and wb format types. > > V2: Change the code to get the drm_framebuffer reference and not copy its > contents(Thomas Zimmermann). > V3: Drop the refcount in the wb code(Thomas Zimmermann). > V5: Add {wb,plane}_format_transform_func to vkms_writeback_job > and vkms_plane_state (Pekka Paalanen) > > Signed-off-by: Igor Torrente > --- > drivers/gpu/drm/vkms/vkms_composer.c | 4 ++-- > drivers/gpu/drm/vkms/vkms_drv.h | 31 +++++++++++++++++++++------ > drivers/gpu/drm/vkms/vkms_plane.c | 10 ++++----- > drivers/gpu/drm/vkms/vkms_writeback.c | 20 ++++++++++++++--- > 4 files changed, 49 insertions(+), 16 deletions(-) > > diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c > index 2d946368a561..95029d2ebcac 100644 > --- a/drivers/gpu/drm/vkms/vkms_composer.c > +++ b/drivers/gpu/drm/vkms/vkms_composer.c > @@ -153,7 +153,7 @@ static void compose_plane(struct vkms_frame_info *primary_plane_info, > struct vkms_frame_info *plane_frame_info, > void *vaddr_out) > { > - struct drm_framebuffer *fb = &plane_frame_info->fb; > + struct drm_framebuffer *fb = plane_frame_info->fb; > void *vaddr; > void (*pixel_blend)(const u8 *p_src, u8 *p_dst); > > @@ -175,7 +175,7 @@ static int compose_active_planes(void **vaddr_out, > struct vkms_frame_info *primary_plane_info, > struct vkms_crtc_state *crtc_state) > { > - struct drm_framebuffer *fb = &primary_plane_info->fb; > + struct drm_framebuffer *fb = primary_plane_info->fb; > struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0); > const void *vaddr; > int i; > diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h > index 2e6342164bef..2704cfb6904b 100644 > --- a/drivers/gpu/drm/vkms/vkms_drv.h > +++ b/drivers/gpu/drm/vkms/vkms_drv.h > @@ -22,13 +22,8 @@ > > #define NUM_OVERLAY_PLANES 8 > > -struct vkms_writeback_job { > - struct dma_buf_map map[DRM_FORMAT_MAX_PLANES]; > - struct dma_buf_map data[DRM_FORMAT_MAX_PLANES]; > -}; > - > struct vkms_frame_info { > - struct drm_framebuffer fb; > + struct drm_framebuffer *fb; > struct drm_rect src, dst; > struct dma_buf_map map[DRM_FORMAT_MAX_PLANES]; > unsigned int offset; > @@ -36,6 +31,29 @@ struct vkms_frame_info { > unsigned int cpp; > }; > > +struct pixel_argb_u16 { > + u16 a, r, g, b; > +}; > + > +struct line_buffer { > + size_t n_pixels; > + struct pixel_argb_u16 *pixels; > +}; > + > +typedef void > +(*wb_format_transform_func)(struct vkms_frame_info *frame_info, > + const struct line_buffer *buffer, int y); > + > +typedef void > +(*plane_format_transform_func)(struct line_buffer *buffer, > + const struct vkms_frame_info *frame_info, int y); It wasn't immediately obvious to me in which direction these function types work from their names. The arguments are not wb and plane but vkms_frame_info and line_buffer in both. The implementations of these functions would have nothing specific to a wb or a plane either, would they? What about naming them frame_to_line_func and line_to_frame_func? > + > +struct vkms_writeback_job { > + struct dma_buf_map data[DRM_FORMAT_MAX_PLANES]; > + struct vkms_frame_info frame_info; Which frame_info is this? Should the field be called wb_frame_info? > + wb_format_transform_func format_func; line_to_frame_func wb_write; perhaps? The type explains the general type of the function, and the field name refers to what it is used for. > +}; > + > /** > * vkms_plane_state - Driver specific plane state > * @base: base plane state > @@ -44,6 +62,7 @@ struct vkms_frame_info { > struct vkms_plane_state { > struct drm_shadow_plane_state base; > struct vkms_frame_info *frame_info; > + plane_format_transform_func format_func; Similarly here, maybe frame_to_line_func plane_read; perhaps? > }; > > struct vkms_plane { > diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c > index a56b0f76eddd..28752af0118c 100644 > --- a/drivers/gpu/drm/vkms/vkms_plane.c > +++ b/drivers/gpu/drm/vkms/vkms_plane.c > @@ -50,12 +50,12 @@ static void vkms_plane_destroy_state(struct drm_plane *plane, > struct vkms_plane_state *vkms_state = to_vkms_plane_state(old_state); > struct drm_crtc *crtc = vkms_state->base.base.crtc; > > - if (crtc) { > + if (crtc && vkms_state->frame_info->fb) { > /* dropping the reference we acquired in > * vkms_primary_plane_update() > */ > - if (drm_framebuffer_read_refcount(&vkms_state->frame_info->fb)) > - drm_framebuffer_put(&vkms_state->frame_info->fb); > + if (drm_framebuffer_read_refcount(vkms_state->frame_info->fb)) > + drm_framebuffer_put(vkms_state->frame_info->fb); > } > > kfree(vkms_state->frame_info); > @@ -110,9 +110,9 @@ static void vkms_plane_atomic_update(struct drm_plane *plane, > frame_info = vkms_plane_state->frame_info; > memcpy(&frame_info->src, &new_state->src, sizeof(struct drm_rect)); > memcpy(&frame_info->dst, &new_state->dst, sizeof(struct drm_rect)); > - memcpy(&frame_info->fb, fb, sizeof(struct drm_framebuffer)); > + frame_info->fb = fb; This change, replacing the memcpy with storing a pointer, seems to be another major point of this patch. Should it be a separate patch? It doesn't seem to fit with the current commit message. I have no idea what kind of locking or referencing a drm_framebuffer would need, and I suspect that would be easier to review if it was a patch of its own. > memcpy(&frame_info->map, &shadow_plane_state->data, sizeof(frame_info->map)); > - drm_framebuffer_get(&frame_info->fb); > + drm_framebuffer_get(frame_info->fb); Does drm_framebuffer_get() not return anything? To me it would be more idiomatic to write something like frame_info->fb = drm_framebuffer_get(fb); I don't know if that pattern is used in the kernel, but I use it in userspace to emphasise that frame_info owns a new reference rather than borrowing someone else's. Thanks, pq > frame_info->offset = fb->offsets[0]; > frame_info->pitch = fb->pitches[0]; > frame_info->cpp = fb->format->cpp[0]; > diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c > index 746cb0abc6ec..ad4bb1fb37ca 100644 > --- a/drivers/gpu/drm/vkms/vkms_writeback.c > +++ b/drivers/gpu/drm/vkms/vkms_writeback.c > @@ -74,12 +74,15 @@ static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector, > if (!vkmsjob) > return -ENOMEM; > > - ret = drm_gem_fb_vmap(job->fb, vkmsjob->map, vkmsjob->data); > + ret = drm_gem_fb_vmap(job->fb, vkmsjob->frame_info.map, vkmsjob->data); > if (ret) { > DRM_ERROR("vmap failed: %d\n", ret); > goto err_kfree; > } > > + vkmsjob->frame_info.fb = job->fb; > + drm_framebuffer_get(vkmsjob->frame_info.fb); > + > job->priv = vkmsjob; > > return 0; > @@ -98,7 +101,9 @@ static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector, > if (!job->fb) > return; > > - drm_gem_fb_vunmap(job->fb, vkmsjob->map); > + drm_gem_fb_vunmap(job->fb, vkmsjob->frame_info.map); > + > + drm_framebuffer_put(vkmsjob->frame_info.fb); > > vkmsdev = drm_device_to_vkms_device(job->fb->dev); > vkms_set_composer(&vkmsdev->output, false); > @@ -115,14 +120,23 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn, > struct drm_writeback_connector *wb_conn = &output->wb_connector; > struct drm_connector_state *conn_state = wb_conn->base.state; > struct vkms_crtc_state *crtc_state = output->composer_state; > + struct drm_framebuffer *fb = connector_state->writeback_job->fb; > + struct vkms_writeback_job *active_wb; > + struct vkms_frame_info *wb_frame_info; > > if (!conn_state) > return; > > vkms_set_composer(&vkmsdev->output, true); > > + active_wb = conn_state->writeback_job->priv; > + wb_frame_info = &active_wb->frame_info; > + > spin_lock_irq(&output->composer_lock); > - crtc_state->active_writeback = conn_state->writeback_job->priv; > + crtc_state->active_writeback = active_wb; > + wb_frame_info->offset = fb->offsets[0]; > + wb_frame_info->pitch = fb->pitches[0]; > + wb_frame_info->cpp = fb->format->cpp[0]; > crtc_state->wb_pending = true; > spin_unlock_irq(&output->composer_lock); > drm_writeback_queue_job(wb_conn, connector_state);